propeller shaft requirements

Pt C, Ch 1, Sec 5

Rules for Inland Waterway Ships 2011 79

SECTION 5 MAIN PROPULSION SHAFTING

1 General

1.1 Application

1.1.1 This Section applies to shafts, couplings, clutchesand other shafting components transmitting power for mainpropulsion.

For shafting components in engines, gears and thrusters, seeSec 2, Sec 4 and Sec 10, respectively; for propellers, see Sec6.

For vibrations, see Sec 7.

1.2 Documentation to be submitted

1.2.1 The Manufacturer is to submit to the Society forapproval the documents listed in Tab 1.

Plans of power-transmitting parts and shaft liners listed inTab 1 are to include the relevant material specifications.

2 Design and construction

2.1 Materials

2.1.1 General

The use of other materials or steels having values of tensilestrength exceeding the limits given in [2.1.2], [2.1.3] and[2.1.4] will be considered by the Society in each case

2.1.2 Shaft materials

In general, shafts are to be of forged steel having tensile

strength, Rm, between 400 and 800 N/mm2.

Where shafts may experience vibratory stresses close (i.e.higher than 80%) to the permissible stresses for transientoperation, the materials are to have a specified minimum

ultimate tensile strength (Rm) of 500 N/mm2. Otherwise,

materials having a specified minimum ultimate tensile

strength (Rm) of 400 N/mm2 may be used.

Table 1 : Documentation to be submitted

No. Document (drawings, calculations, etc.)

1 Shafting arrangement (1)

2 Thrust shaft

3 Intermediate shafts

4 Propeller shaft

5 Shaft liners, relevant manufacture and welding procedures, if any

6 Couplings and coupling bolts

7 Flexible couplings (2)

8 Sterntube

9 Details of sterntube glands

(1) This drawing is to show the entire shafting, from the main engine coupling flange to the propeller. The location of the thrust block, and the location and number of shafting bearings (type of material and length) are also to be shown.

(2) The Manufacturer of the elastic coupling is also to submit the following data:

allowable mean transmitted torque (static) for continuous operation

maximum allowable shock torque

maximum allowable speed of rotation

maximum allowable values for radial, axial and angular misalignment

In addition, when the torsional vibration calculation of main propulsion system is required (see Sec 9), the following data are also to be submitted:

allowable alternating torque amplitude and power loss for continuous operation, as a function of frequency and/or mean transmitted torque

static and dynamic stiffness, as a function of frequency and/or mean transmitted torque

moments of inertia of the primary and secondary halves of the coupling

damping coefficient or damping capability

properties of rubber components

for steel springs of couplings: chemical composition and mechanical properties of steel employed.

Pt C, Ch 1, Sec 5

80 Rules for Inland Waterway Ships 2011

2.1.3 Couplings, flexible couplings, hydraulic couplings

Non-solid-forged couplings and stiff parts of elastic cou-plings subjected to torque are to be of forged or cast steel,or nodular cast iron.

Rotating parts of hydraulic couplings may be of grey castiron, provided that the peripheral speed does not exceed40m/s.

2.1.4 Coupling boltsCoupling bolts are to be of forged, rolled or drawn steel.

In general, the value of the tensile strength of the bolt mate-rial RmB is to comply with the following requirements:

R m RmB 1,7 R m R mB 1000 N/mm2.

2.1.5 Shaft linersLiners are to be of metallic corrosion resistant material com-plying with the applicable requirements of Part D and withthe approved specification, if any; in the case of liners fabri-cated in welded lengths, the material is to be recognised assuitable for welding.

In general, they are to be manufactured from castings.

For small shafts, the use of liners manufactured from pipesinstead of castings may be considered.

Where shafts are protected against contact with seawaternot by metal liners but by other protective coatings, thecoating procedure is to be approved by the Society.

2.1.6 SterntubesSterntubes are to comply with the "Rules for the Classifica-tion of Ships".

2.2 Shafts - Scantling

2.2.1 GeneralFor the check of the scantling, the methods given in [2.2.2]and [2.2.3] apply for intermediate shafts and propellershafts, respectively. As an alternative, the direct stress calcu-lation method as per [2.2.4] may be applied.

Transitions of diameters are to be designed with either asmooth taper or a blending radius. For guidance, a blendingradius equal to the change in diameter is recommended.

2.2.2 Intermediate and thrust shaftsThe minimum diameter of intermediate and thrust shafts isnot to be less than the value d, in mm, given by the follow-ing formula:

where:

Q : in the case of solid shafts: Q = 0

in the case of hollow shafts: Q = ratio of thehole diameter to the outer shaft diameter inthe section concerned.

where Q 0,4, Q = 0 is to be taken.Hollow shafts whose longitudinal axis doesnot coincide with the longitudinal hole axis

will be specially considered by the Societyin each case.

F : 95 for main propulsion systems poweredby diesel engines fitted with slip type cou-pling, by turbines or by electric motors;

100 for main propulsion systems poweredby diesel engines fitted with other type ofcouplings.

k : Factor whose value is given in Tab 2 dependingupon the different design features of the shafts.

For shaft design features other than those givenin the Table, the value of k will be speciallyconsidered by the Society in each case.

n : Speed of rotation of the shaft, in r.p.m., corre-sponding to power P

P : Maximum continuous power of the propulsionmachinery for which the classification isrequested, in kW.

Rm : Value of the minimum tensile strength of the

shaft material, in N/mm2. Whenever the use of a

steel having Rm in excess of 800 N/mm2 is

allowed in accordance with [2.1], the value ofRm to be introduced in the above formula is not

to exceed the following:

for carbon and carbon manganese steels, aminimum specified tensile strength not

exceeding 760 N/mm2

for alloy steels, a minimum specified tensile

strength not exceeding 800 N/mm2.

Where materials with greater specified or actualtensile strengths than the limitations givenabove are used, reduced shaft dimensions arenot acceptable when derived from the formulain this item [2.2.2].

In cases of stainless steels and in other particu-lar cases, at the discretion of the Society, thevalue of Rm to be introduced in the above for-

mula will be specially considered.

The scantlings of intermediate shafts inside tubes or stern-tubes will be subject to special consideration by the Society.Where intermediate shafts inside sterntubes are water lubri-cated, the requirements of [2.4.7] are to be applied.

2.2.3 Propeller shaftsFor propeller shafts in general a minimum specified tensilestrength Rm to be introduced in the following formula not

exceeding 600 N/mm2 is to be taken for carbon, carbonmanganese and alloy steel.

Where materials with greater specified or actual tensilestrengths than the limitations given above are used, reducedshaft dimensions are not acceptable when derived from theformula in this item [2.2.3].

The minimum diameter of the propeller shaft is not to beless than the value dP, in mm, given by the following for-

mula:

where:

d F kP

n 1 Q4 )(------------------------------560

Rm 160+-----------------------

1 3

=

dP 100 kPP

n 1 Q4 )(------------------------------560

Rm 160+-----------------------

1 3

=

Pt C, Ch 1, Sec 5


kp : Factor whose value, depending on the different

constructional features of shafts, is given below.

The other symbols have the same meaning as in [2.2.2].

In cases of stainless steels and in other particular cases, atthe discretion of the Society, the value of Rm to be intro-

duced in the above formula will be specially considered. Ingeneral, the diameter of the part of the propeller shaftlocated forward of the forward sterntube seal may be gradu-ally reduced to the diameter of the intermediate shaft.

The values of factor kP to be introduced in the above for-

mula are to be taken as follows:

kP : kP = 1,26, for propeller shafts where:

the propeller is keyed on to the shaft taper incompliance with the requirements of[2.5.5]

kP = 1,22, for propeller shafts where:

the propeller is keyless fitted on to the shafttaper by a shrinkage method in compliancewith Sec 8, [3.1.2], or the propeller boss isattached to an integral propeller shaft flangein compliance with [2.5.1]

the sterntube of the propeller shaft is oillubricated and provided with oil sealingglands approved by the Society or when thesterntube is water lubricated and the propel-ler shaft is fitted with a continuous liner.

The above values of kP apply to the portion of propeller

shaft between the forward edge of the aftermost shaft bear-ing and the forward face of the propeller boss or the forwardface of the integral propeller shaft flange for the connectionto the propeller boss. In no case is the length of this portion

of propeller shaft to be less than 2,5 times the rule diameterdP obtained with the above formula.

The determination of factor kP for shaft design features other

than those given above will be specially considered by theSociety in each case.

For the length of the propeller shaft between the forwardedge of the aftermost shaft bearing and the forward edge ofthe forward sterntube seal:

kP = 1,15 is to be taken in any event.

2.2.4 Direct stress calculation methodAlternative calculation methods may be considered by theSociety. Any alternative calculation method is to include allrelevant loads on the complete dynamic shafting systemunder all permissible operating conditions. Consideration isto be given to the dimensions and arrangements of all shaftconnections.

Moreover, an alternative calculation method is to take intoaccount design criteria for continuous and transient operat-ing loads (dimensioning for fatigue strength) and for peakoperating loads (dimensioning for yield strength). Thefatigue strength analysis may be carried out separatelyaccording to different criteria corresponding to differentload assumptions, for example the following:

low cycle fatigue criterion (typically lower than 104), i.e.the primary cycles represented by zero to full load andback to zero, including reversing torque if applicable

high cycle fatigue criterion (typically much higher than

107), i.e. torsional vibration stresses permitted for con-tinuous operation, reverse bending stresses and opera-tion passing through a barred speed range or any othertransient condition.

Pt C, Ch 1, Sec 5


Table 2 : Values of factor k

For intermediate shafts with For thrust shafts external to engines

integral coupling flange and straight

sections

shrink fit coupling

keyways, tapered or cylindrical connection

radial holelongitudinal

sloton both sides of

thrust collar

in way of axial bearing, where a roller bearing is used as a thrust bearing

1,00 (1) 1,00 (2) 1,10 (3) (4) 1,10 (5) 1,20 (6) 1,10 (1) 1,10

(1) Value applicable in the case of fillet radii in accordance with the provisions of [2.5.1].(2) k refers to the plain shaft section only. Where shafts may experience vibratory stresses close to the permissible stresses for con-

tinuous operation, an increase in diameter to the shrink fit diameter is to be provided, e.g. a diameter increase of 1 to 2 % and a blending radius as described in [2.2.1].

(3) Keyways are, in general, not to be used in installations with a barred speed range.(4) At a distance of not less than 0,2 d from the end of the keyway, the shaft diameter may be reduced to the diameter calculated

using k = 1,0. Fillet radii in the transverse section of the bottom of the keyway are to be not less than 0,0125 d, d being the diameter as calculated above using k = 1,0.

(5) Value applicable in the case of diameter of radial bore dh not exceeding 0,3 d, d being as defined in (4).

Cases foreseeing intersection between a radial and an eccentric (rec) axial bore (see figure below) are specially considered by the Society.

(6) Subject to limitations: slot length (l)/outside diameter < 0,8, inner diameter (di)/outside diameter < 0,8 and slot width (e)/outside diam-

eter > 0,10. The end rounding of the slot is not to be less than e/2. An edge rounding is preferably to be avoided as this increases the stress concentration slightly.The k values are valid for 1, 2 and 3 slots, i.e. with slots at, respectively, 360, 180 and 120 degrees apart.

Note 1: Explanation of k and CK (for CK see Sec 9, Tab 1)

The factors k (for low cycle fatigue) and CK (for high cycle fatigue) take into account the influence of:

the stress concentration factors (scf) relative to the stress concentration for a flange with fillet radius of 0,08 d (geometric stress concentration of approximately 1,45)

where the exponent x considers low cycle notch sensitivity.

the notch sensitivity. The chosen values are mainly representative for soft steels (Rm < 600), while the influence of steep stress

gradients in combination with high strength steels may be underestimated.

the fact that that the size factor cD being a function of diameter only does not purely represent a statistical size influence, but

rather a combination of this statistical influence and the notch sensitivity.

The actual values for k and CK are rounded off.

Note 2: Stress concentration factor of slots

The stress concentration factor (scf) at the end of slots can be determined by means of the following empirical formulae using the symbols in (4)

This formula applies to:

slots at 120 or 180 or 360 degrees apart.

slots with semicircular ends. A multi-radii slot end can reduce the local stresses, but this is not included in this empirical formula.

slots with no edge rounding (except chamfering), as any edge rounding increases the scf slightly.

t(hole) represents the stress concentration of radial holes (in this context e = hole diameter) and can be determined as :

or simplified to t(hole) = 2,3.

Note 3: The determination of k factors for shafts other than those provided in this table will be given special consideration by the Society.

CK1 45,scf------------- and k

scf1 45,-------------

x

==

scf t ho le( ) 0 57,l e( ) d

1did----

ed---

-------------------------------+=

t ho le( ) 2 3, 3ed--- 15

ed---

2

10ed---

2 d id----

2

++=

Pt C, Ch 1, Sec 5


2.3 Liners

2.3.1 GeneralMetal liners or other protective coatings approved by theSociety are required where propeller shafts are not made ofcorrosion-resistant material.

Metal liners are generally to be continuous; however, dis-continuous liners, i.e. liners consisting of two or more sepa-rate lengths, may be accepted by the Society on a case bycase basis, provided that:

they are fitted in way of all supports

the shaft portion between liners, likely to come intocontact with sea water, is protected with a coating ofsuitable material with characteristics, fitting method andthickness approved by the Society.

2.3.2 ScantlingThe thickness of metal liners fitted on propeller shafts or onintermediate shafts inside sterntubes is to be not less thanthe value t, in mm, given by the following formula:

where:

d : Actual diameter of the shaft, in mm.

Between the sternbushes, the above thickness t may bereduced by 25%.

2.4 Stern tube bearings2.4.1 Oil lubricated aft bearings of antifriction

metala) The length of bearings lined with white metal or other

antifriction metal and with oil glands of a type approvedby the Society is to be not less than twice the rule diam-eter of the shaft in way of the bearing.

b) The length of the bearing may be less than that given in(a) above, provided the nominal bearing pressure is not

more than 0,8 N/mm2, as determined by static bearingreaction calculations taking into account shaft and pro-peller weight, as exerting solely on the aft bearing,divided by the projected area of the shaft.

However, the minimum bearing length is to be not lessthan 1,5 times its actual inner diameter.

2.4.2 Oil lubricated aft bearings of synthetic rubber, reinforced resin or plastics material

a) For bearings of synthetic rubber, reinforced resin or plas-tics material which are approved by the Society for useas oil lubricated sternbush bearings, the length of thebearing is to be not less than twice the rule diameter ofthe shaft in way of the bearing.

b) The length of the bearing may be less than that given in(a) above provided the nominal bearing pressure is not

more than 0,6 N/mm2, as determined according to[2.4.1] b).

However, the minimum length of the bearing is to benot less than 1,5 times its actual inner diameter.

Where the material has proven satisfactory testing andoperating experience, consideration may be given to anincreased bearing pressure.

2.4.3 Water lubricated aft bearings of lignum vitae or antifriction metal

Where the bearing comprises staves of wood (known as"lignum vitae") or is lined with antifriction metal, the lengthof the bearing is to be not less than 4 times the rule diame-ter of the shaft in way of the bearing.

2.4.4 Water lubricated aft bearings of synthetic materials

a) Where the bearing is constructed of synthetic materialswhich are approved by the Society for use as waterlubricated sternbush bearings, such as rubber or plas-tics, the length of the bearing is to be not less than 4times the rule diameter of the shaft in way of the bear-ing.

b) For a bearing design substantiated by experimental datato the satisfaction of the Society, consideration may begiven to a bearing length less than 4 times, but in nocase less than 2 times, the rule diameter of the shaft inway of the bearing.

2.4.5 Grease lubricated aft bearingsThe length of grease lubricated bearings is generally to benot less than 4 times the rule diameter of the shaft in way ofthe bearing.

2.4.6 Oil or grease lubrication systema) For oil lubricated bearings, provision for oil cooling is to

be made.

A gravity tank is to be fitted to supply lubricating oil tothe sterntube; the tank is to be located above the fullload waterline.

Oil sealing glands are to be suitable for the various seawater temperatures which may be encountered in serv-ice.

b) Grease lubricated bearings will be specially consideredby the Society.

2.4.7 Water circulation systemFor water lubricated bearings, means are to be provided toensure efficient water circulation. In the case of bearingslined with "lignum vitae" of more than 400 mm in diameterand bearings lined with synthetic materials, means forforced water circulation are to be provided. In the case ofbearings of synthetic materials, water flow indicators orpump outlet pressure indicators are to be provided.

The water grooves on the bearings are to be of ample sec-tion such as to ensure efficient water circulation and bescarcely affected by wear-down, particularly for bearings ofthe plastic type.

The shut-off valve or cock controlling the water supply is tobe fitted direct to the stuffing box bulkhead or in way of thewater inlet to the sterntube, when this is fitted forward ofsuch bulkhead.

2.5 Couplings

2.5.1 Flange couplings a) Flange couplings of intermediate and thrust shafts and

the flange of the forward coupling of the propeller shaftare to have a thickness not less than 0,2 times the rule

td 230+

32-------------------=

Pt C, Ch 1, Sec 5


diameter of the solid intermediate shaft and not lessthan the coupling bolt diameter calculated for a tensilestrength equal to that of the corresponding shaft.

The fillet radius at the base of solid forged flanges is tobe not less than 0,08 times the actual shaft diameter.

The fillet may be formed of multi-radii in such a waythat the stress concentration factor will not be greaterthan that for a circular fillet with radius 0,08 times theactual shaft diameter.

For non-solid forged flange couplings, the above filletradius is not to cause a stress in the fillet higher than thatcaused in the solid forged flange as above.

Fillets are to have a smooth finish and are not to berecessed in way of nuts and bolt heads.

b) Where the propeller is connected to an integral propel-ler shaft flange, the thickness of the flange is to be notless than 0,25 times the rule diameter of the aft part ofthe propeller shaft. The fillet radius at the base of theflange is to be not less than 0,125 times the actual diam-eter.

The strength of coupling bolts of the propeller boss tothe flange is to be equivalent to that of the aft part of thepropeller shaft.

c) Non-solid forged flange couplings and associated keysare to be of a strength equivalent to that of the shaft.

They are to be carefully fitted and shrunk on to theshafts, and the connection is to be such as to reliablyresist the vibratory torque and astern pull.

d) For couplings of intermediate and thrust shafts and forthe forward coupling of the propeller shaft having all fit-ted coupling bolts, the coupling bolt diameter in way ofthe joining faces of flanges is not to be less than thevalue dB, in mm, given by the following formula:

where:

d : Rule diameter of solid intermediate shaft, inmm, taking into account the ice strengthen-ing requirements of Pt F, Ch 9, Sec 3, whereapplicable

nB : Number of fitted coupling bolts

DC : Pitch circle diameter of coupling bolts, in

mm

Rm : Value of the minimum tensile strength of

intermediate shaft material taken for calcu-

lation of d, in N/mm2

RmB : Value of the minimum tensile strength of

coupling bolt material, in N/mm2. Where, incompliance with [2.1.1], the use of a steelhaving RmB in excess of the limits specified

in [2.1.4] is allowed for coupling bolts, thevalue of RmB to be introduced in the formula

is not exceed the above limits.

e) Flange couplings with non-fitted coupling bolts may beaccepted on the basis of the calculation of bolt tighten-

ing, bolt stress due to tightening, and assembly instruc-tions.

To this end, the torque based on friction between themating surfaces of flanges is not to be less than 2,8 timesthe transmitted torque, assuming a friction coefficientfor steel on steel of 0,18. In addition, the bolt stress dueto tightening in way of the minimum cross-section is notto exceed 0,8 times the minimum yield strength (ReH), or

0,2 proof stress (Rp 0,2), of the bolt material.

Transmitted torque has the following meanings:

For main propulsion systems powered by dieselengines fitted with slip type or high elasticity cou-plings, by turbines or by electric motors: the meantransmitted torque corresponding to the maximumcontinuous power P and the relevant speed of rota-tion n, as defined under [2.2.2].

For main propulsion systems powered by dieselengines fitted with couplings other than those men-tioned in (a): the mean torque above increased by20% or by the torque due to torsional vibrations,whichever is the greater.

The value 2,8 above may be reduced to 2,5 in the fol-lowing cases:

ships having two or more main propulsion shafts

when the transmitted torque is obtained, for thewhole functioning rotational speed range, as thesum of the nominal torque and the alternate torquedue to the torsional vibrations, calculated asrequired in Sec 9.

2.5.2 Shrunk couplingsNon-integral couplings which are shrunk on the shaft bymeans of the oil pressure injection method or by othermeans may be accepted on the basis of the calculation ofshrinking and induced stresses, and assembly instructions.

To this end, the force due to friction between the matingsurfaces is not to be less than 2,8 times the total force due tothe transmitted torque and thrust.

The value 2,8 above may be reduced to 2,5 in the casesspecified under item e) of [2.5.1].

The values of 0,14 and 0,18 will be taken for the frictioncoefficient in the case of shrinking under oil pressure anddry shrink fitting, respectively.

In addition, the equivalent stress due to shrinkage deter-mined by means of the von Mises-Hencky criterion in thepoints of maximum stress of the coupling is not to exceed0,8 times the minimum yield strength (ReH), or 0,2% proof

stress (Rp0,2), of the material of the part concerned.

The transmitted torque is that defined under item e) of[2.5.1].

For the determination of the thrust, see Sec 6, [3.1.2].

2.5.3 Other couplingsTypes of couplings other than those mentioned in [2.5.1]and [2.5.2] above will be specially considered by the Soci-ety.

dB 0 65,d3 Rm 160+( )

nB DC RmB --------------------------------------

0 5,

=

Pt C, Ch 1, Sec 5


2.5.4 Flexible couplingsa) The scantlings of stiff parts of flexible couplings sub-

jected to torque are to be in compliance with therequirements of Article [2].

b) For flexible components, the limits specified by theManufacturer relevant to static and dynamic torque,speed of rotation and dissipated power are not to beexceeded.

c) Where all the engine power is transmitted through oneflexible component only (ships with one propulsionengine and one shafting only), the flexible coupling is tobe fitted with a torsional limit device or other suitablemeans to lock the coupling should the flexible compo-nent break.

In stiff transmission conditions with the above lockingdevice, a sufficiently wide speed range is to be pro-vided, free from excessive torsional vibrations, such asto enable safe navigation and steering of the ship. As analternative, a spare flexible element is to be provided onboard.

2.5.5 Propeller shaft keys and keywaysa) Keyways on the propeller shaft cone are to have well

rounded corners, with the forward end faired and pref-erably spooned, so as to minimize notch effects andstress concentrations.

When these constructional features are intended toobtain an extension of the interval between surveys ofthe propeller shaft in accordance with the relevant pro-visions of Pt A, Ch 2, Sec 2, [5.5], they are to be in com-pliance with Fig 1.

Different scantlings may be accepted, provided that atleast the same reduction in stress concentration isensured.

The fillet radius at the bottom of the keyway is to be notless than 1,25% of the actual propeller shaft diameter atthe large end of the cone.

The edges of the key are to be rounded.

The distance from the large end of the propeller shaftcone to the forward end of the key is to be not less than20% of the actual propeller shaft diameter in way of thelarge end of the cone.

Key securing screws are not to be located within the firstone-third of the cone length from its large end; theedges of the holes are to be carefully faired.

b) The sectional area of the key subject to shear stress is to

be not less than the value A, in mm2, given by the fol-lowing formula:

where:

d : Rule diameter, in mm, of the intermediateshaft calculated in compliance with therequirements of [2.2.2], assuming:

Rm = 400 N/mm2

dPM : Actual diameter of propeller shaft at mid-

length of the key, in mm.

2.6 Control and monitoring

2.6.1 IndicatorsThe local indicators for main propulsion shafting to beinstalled on ships of 500 gross tonnage and upwards with-out automation notations are given in Tab 3. For monitoringof engines, gears, controllable pitch propellers and thrust-ers, see Sec 2, Sec 4, Sec 6 and Sec 10, respectively.

The indicators listed in Tab 3 are to be fitted at a normallyattended position.

Note 1: Some departures from Tab 3 may be accepted by the Soci-ety in the case of ships with a restricted navigation notation

Figure 1 : Details of forward end of propeller shaft keyway

A 0 4,d3

dPM--------=

r

321r < r < r

0,0125 d

ABC

ABC

o

o

d

2 t

o 0,2 d 4 t

t

C - C1r

r

B - B2r

r

A - A3r

r

tt t t

Pt C, Ch 1, Sec 5


3 Arrangement and installation

3.1 General3.1.1 The installation is to be carried out according to theinstructions of the component Manufacturer or approveddocuments, when required.

3.1.2 The installation of sterntubes and/or associated non-shrunk bearings is subject to approval of procedures andmaterials used.

3.1.3 The joints between liner parts are not to be locatedin way of supports and sealing glands.

Metal liners are to be shrunk on to the shafts by pre-heatingor forced on by hydraulic pressure with adequate interfer-ence; dowels, screws or other means of securing the linersto the shafts are not acceptable.

3.2 Protection of propeller shaft against cor-rosion

3.2.1 The propeller shaft surface between the propellerand the sterntube, and in way of propeller nut, is to be suit-ably protected in order to prevent any entry of sea water,unless the shaft is made of austenitic stainless steel.

4 Material tests, workshop inspection and testing, certification

4.1 Material and non-destructive tests, workshop inspections and testing

4.1.1 Material testsShafting components are to be tested in accordance withTab 4 and in compliance with the requirements of Part D.

Magnetic particle or liquid penetrant tests are required forthe parts listed in Tab 4 and are to be effected in positionsmutually agreed upon by the Manufacturer and the Sur-veyor, where experience shows defects are most likely tooccur.

4.1.2 Hydrostatic testsParts of hydraulic couplings, clutches of hydraulic reversegears and control units, hubs and hydraulic cylinders ofcontrollable pitch propellers, including piping systems andassociated fittings, are to be hydrostatically tested to1,5times the maximum working pressure.

Sterntubes, when machine-finished, and propeller shaft lin-ers, when machine-finished on the inside and with an over-thickness not exceeding 3 mm on the outside, are to behydrostatically tested to 0,2 MPa.

4.2 Certification

4.2.1 Testing certificationSocietys certificates (C) (see Pt D, Ch 1, Sec 1, [4.2.1]) arerequired for material tests of components in items 1 to 5 ofTab 4.

Works certificates (W) (see Pt D, Ch 1, Sec 1, [4.2.3]) arerequired for hydrostatic tests of components indicated in[4.1.2] and for material and non-destructive tests of compo-nents in items of Tab 4 other than those for which Societyscertificates (C) are required.

Table 3 : Shafting of propulsion machinery

Symbol convention

H = High, HH = High high, G = group alarm

L = Low, LL = Low low, I = individual alarm

X = function is required, R = remote

Monitoring

Automatic control

Main Engine Auxiliary

Identification of system parameter AlarmIndica-

tionSlow-down

Shut-down

ControlStand

by StartStop

Temperature of each shaft thrust bearing

(non applicable for ball or roller bearings)

H X

Stern tube bush oil gravity tank level L

Pt C, Ch 1, Sec 5


Table 4 : Material and non-destructive tests

Shafting component

Material tests

(Mechanical properties and chemical composition)

Non-destructive tests

Magnetic particle or liquid penetrant

Ultrasonic

1) Coupling (separate from shafts) all if diameter 250 mm if diameter 250 mm

2) Propeller shafts all if diameter 250 mm if diameter 250 mm

3) Intermediate shafts all if diameter 250 mm if diameter 250 mm

4) Thrust shafts all if diameter 250 mm if diameter 250 mm

5) Cardan shafts (flanges, crosses, shafts, yokes) all if diameter 250 mm if diameter 250 mm

6) Sterntubes all - -

7) Sterntube bushes and other shaft bearings all - -

8) Propeller shaft liners all - -

9) Coupling bolts or studs all - -

10) Flexible couplings (metallic parts only) all - -

11) Thrust sliding-blocks (frame only) all - -

Pt D, Ch 2, Sec 3


refer to the as forged mass and length but exclude the testmaterial).

2.6.2 In the case of batch testing, the number of test sam-ples is indicated in [1.11.3].

2.6.3 The test specimens for 1 tensile and, when required,3 Charpy V-notch impact tests are to be taken from each testsample.

The test specimens are to be cut in a longitudinal direction.At the discrection of the Manufacturer, the alternative direc-tions shown in Fig 1, Fig 2 and Fig 3 may be used.

2.6.4 For forgings operating at 0C or lower temperature,which are not dealt with in this Article, the applicablerequirements are stipulated on a case-by-case basis,depending on the design temperature, application anddimensions; see also Article [8]. Forgings intended for thestructure of the poop are to be made of fine grained steeland impact tested on longitudinal Charpy V-notch speci-mens.

The impact energy is to be not lower than 27 J at 0C.

Forgings intended for the rudder stock and pintles of shipswith ice class notation are to be made of fine grained steeland impact tested on Charpy V-notch longitudinal speci-mens. The impact energy is to be not lower than 27 J at -20C.

2.7 Non-destructive examination

2.7.1 An ultrasonic examination and magnetic particleinspection are to be carried out on class 1 forgings, whenrequired by the construction Rules of the finished products,by the approved plans or, in specific cases, by the Surveyor.

3 Forgings for machinery, shafts and equipment

3.1 Application

3.1.1 The requirements of this Article apply to carbon, car-bon-manganese and alloy steel forgings, intended for use inthe construction of machinery, shafts and equipment and/ornot specifically dealt with in the other Articles of this Sec-tion and where design and acceptance tests are related tomechanical properties at ambient temperature.

Specific requirements for anchors are given in Ch 4, Sec 1,[1].

3.1.2 Forgings intended for propeller shafts, intermediateand thrust shafts, hubs, piston rods, connecting rods, crossheads belong to class 1; unless otherwise specified on acase-by-case basis, other forgings belong to class 2.

3.2 Steel grades

3.2.1 The grades are identified by one of the symbols FC(forgings in carbon and carbon-manganese steels) or FA(forgings in alloy steels), followed by a number indicating

the specified minimum tensile strength Rm in N/mm2.

3.2.2 Limits on the specified mechanical properties aregiven in Pt C, Ch 1, Sec 5 for forgings intended for mainpropulsion shafting.

3.3 Condition of supply

3.3.1 The forgings are to be supplied in one of the follow-ing conditions, as required (see [1.9.2]):

a) Carbon and C-Mn steel forgings

fully annealed

normalised

normalised and tempered

quenched and tempered

b) Alloy steels forgings

quenched and tempered.

For all types of steel the tempering temperature is to be notless than 550C.

Alternatively, alloy steel forgings may be supplied in thenormalised and tempered condition, in which case thespecified mechanical properties are to be agreed withRINA.

Where the specified minimum tensile strength exceed 700

N/mm2, forgings in carbon manganese steel are to be sup-plied in the quenched and tempered condition only.

3.4 Chemical composition

3.4.1 GeneralAll forgings are to be made from killed or killed and finegrained steel, as required, and their chemical compositionis to comply with the limits indicated in Tab 3 or, whereapplicable, the requirements of the approved specification.

The chemical composition is to be appropriate for the typeof steel, dimensions and required mechanical properties ofthe forgings.

Forgings intended for welded construction may be requiredby RINA to be made from fine grained steel.

The chemical composition of each heat is to be determinedby the Manufacturer on a sample taken preferably duringthe pouring of the heat. When multiple heats are tappedinto a common ladle, the ladle analysis is to apply.

3.5 Mechanical properties

3.5.1 The requirements for the yield stress, elongation andimpact energy are given, for the different strength levels, inTab 4.

3.6 Mechanical tests

3.6.1 In the case of individual testing [1.11.2], at least onetest sample is to be taken for the required tests from the endof each forging.

Where a forging exceeds both 4 t in mass and 3 m in length,one test sample is to be taken from each end (these limitsrefer to the as forged mass and length but exclude the testmaterial).

Pt D, Ch 2, Sec 3


3.6.2 In the case of batch testing, the number of test sam-ples is indicated in [1.11.3].

3.6.3 The test specimens for 1 tensile and, when required,3 Charpy V- notch impact tests are to be taken from eachtest sample in accordance with Fig 1, Fig 2 and Fig 3.

The specimens are to be taken in a longitudinal direction(position A). At the discretion of the Manufacturer, the alter-native directions or positions B, C and D may be used.

Figure 1 : Plain shaft

Figure 2 : Flanged shaft

Figure 3 : Flanged shaft with collar

3.6.4

For forgings operating at 0C or lower temperature, theapplicable requirements are to be stipulated on a case-by-case basis, depending on the design temperature, applica-tion and dimensions. See also Article [8].

Forgings intended for propeller shafts of ships with ice classnotation are to be made of killed or killed and fine grainedsteel, as required, and the average impact energy is to be

not lower than 27 J at the following temperatures for the dif-ferent notations:

a) 0C for ships with notations IC

b) -10C for ships with notations IAS, IA or IB.

3.7 Non-destructive examination

3.7.1 A magnetic particle or liquid penetrant examinationis to be carried out on forgings intended for:

a) rudder stocks and pintles with diameter not lower than100 mm

b) main propulsion shafting with diameter not lower than100 mm

c) connecting rods

d) components for engines having bore diameter largerthan 400 mm, such as:

cylinder covers, piston crowns, piston rods, tie rods,gear wheels for camshaft drives

bolts and studs for cylinder covers, cross heads,main bearing and connecting rod bearings, nuts fortie rods.

Magnetic particle or liquid penetrant tests are to be carriedout in positions mutually agreed upon by the Manufacturerand the Surveyor, where experience shows defects are mostlikely to occur.

The magnetic particle test of tie rods/stay bolts is to be car-ried out at each threaded portion which is at least twice thelength of the thread.

3.7.2 Ultrasonic testing is to be carried out on the follow-ing items:

a) rudder stocks and pintles with diameter not lower than200 mm

b) shafts having a finished diameter of 200 mm or larger,when intended for main propulsion or other essentialservices

c) piston crowns and cylinders covers

d) piston and connecting rods with connecting rod bearingcaps, for engines having a bore diameter greater than400 mm.

4 Forgings for crankshafts

4.1 Application

4.1.1 The requirements of this Article apply to carbon-manganese and alloy steel solid forged crankshafts andforgings to be used for the construction of semi-built or fullybuilt crankshafts.

The general requirements, specified in Article [1], are alsoto be complied with, as appropriate.

4.1.2 Forgings intended for crankshafts belong to class 1.

4.2 Steel grades

4.2.1 The steel specification relevant to chemical compo-sition, mechanical properties and heat treatment is to besubmitted for approval.

Test position B(tangential)

Test position A (longitudinal)

Test position B(longitudinal)

(through bolt hole) Test position A(longitudinal)

Test position C(tangential)

Test position B(tangential)

Test position C(tangential)

Test position A (longitudinal)

Test position D(tangential)

Pt D, Ch 2, Sec 3


Table 3 : Chemical composition limits (1) for machinery steel forgings

Table 4 : Mechanical properties for machinery steel forgings

Steel type C Si Mn P S Cr Mo Ni Cu (2)Total

residuals

C, C - Mn 0,65 (1) 0,45 0,30

1,50

0,035 0,035 0,30 (2) 0,15 (2) 0,40 (2) 0,30 0,85

Alloy (4) 0,45 0,45 0,30

1,00

0,035 0,035 Min 0,40 (5)

Min 0,15 (5)

Min 0,40 (5)

0,30 -

(1) Composition in percentage mass by mass maximum unless shown as a range or as a minimum.

(2) The carbon content of C and C-Mn steel forgings intended for welded construction is to be 0,23 maximum. The carbon content may be increased above this level provided that the carbon equivalent (Ceq) is not more than 0,41%.

(3) Elements are considered as residual elements unless shown as a minimum.

(4) Where alloy steel forgings are intended for welded constructions, the proposed chemical composition is subject to approval by the Classification Society.

(5) One or more of the elements is to comply with the minimum content.

Steel type

Tensile strength Rm

min. N/mm2

(1)

Yield stress

Re min.

N/mm2

Elongation A5 min. (%) Reduction of area Z min. (%)

Hardness (Brinell) (3)

Long. Tang. Long. Tang.

C and C-Mn 400 200 26 19 50 35 110-150

440 220 24 18 50 35 125-160

480 240 22 16 45 30 135-175

520 260 21 15 45 30 150-185

560 280 20 14 40 27 160-200

600 300 18 13 40 27 175-215

640 320 17 12 40 27 185-230

680 340 16 12 35 24 200-240

720 360 15 11 35 24 210-250

760 380 14 10 35 24 225-265

Alloy 600 360 18 14 50 35 175-215

700 420 16 12 45 30 205-245

800 480 14 10 40 27 235-275

900 630 13 9 40 27 260-320

1000 700 12 8 35 24 290-365

1100 770 11 7 35 24 320-385

(1) The following ranges for tensile strength may be additionally specified:

specified minimum tensile strength: < 900 N/mm2 900 N/mm2

tensile strength range: 150 N/mm2 200 N/mm2

(2) For propeller shafts intended for ships with ice class notation Charpy V-notch impact testing according to [3.6.4] is to be per-formed.

(3) The hardness values are typical and are given for information purposes only.

Pt D, Ch 1, Sec 1


SECTION 1 MANUFACTURE, INSPECTION, CERTIFICATION

1 General

1.1 Application

1.1.1 Part D specifies in Chapter 2 to Chapter 4 therequirements for the manufacture, inspection and certifica-tion of steel and iron products, non-ferrous metals, variousfinished products and equipment such as propellers, pres-sure bottles, anchors, chain cables, ropes and sidescuttles,entering in the construction or repair of ships which are sur-veyed for classification purposes.

The general requirements relevant to the manufacture,inspection and certification of the above-mentioned materi-als and products, hereafter generally referred to as prod-ucts, are given in this Chapter and are to be complied withas applicable.

The requirements of Chapter 1 are also applicable, asappropriate, to products covered by other parts of the Rules.

Part D specifies in Chapter 5 the requirements for approvalof welding consumables and qualification of welding pro-cedures.

1.1.2 In addition to Part D, the requirements given for cer-tain materials, procedures and products in the other Parts ofthe Rules or specified on the approved plans, are also appli-cable, where appropriate.

1.1.3 Products subject to the requirements of Part D andthe relevant testing operations are those laid down in therelevant Rules of RINA dealing with the design, inspectionat works and testing of products, unless otherwise specified.

1.1.4 Products with properties departing appreciably fromthose covered by the Rules may be used with the approvalof RINA.

1.2 Other specifications

1.2.1 Products complying with international, national orproprietary specifications may be accepted by RINA, pro-vided such specifications give reasonable equivalence tothe requirements of these Rules or are approved for a spe-cific application.

Such products, when accepted, are designated by theirstandard identification mark or as agreed at the time of theapproval.

Unless otherwise agreed, inspection and certification ofproducts complying with other specifications are to be car-ried out in accordance with the requirements of the Rules.

1.3 Information to be supplied by the pur-chaser

1.3.1 The purchaser is to provide the Manufacturer withthe information necessary to ensure that products are testedin accordance with these Rules; optional or additional con-ditions are also to be clearly indicated.

2 Manufacture and quality

2.1 General 2.1.1 Manufacture Manufacturers and their individual works are to be recog-nised by RINA for the type of products fabricated.

To this end plants, production and treatment procedures,testing machines, laboratories for analyses, internal controlsystems and personnel qualification are to be suitable in theopinion of RINA.

Manufacturing procedures and techniques are to be such asto reasonably ensure constant compliance of the productwith the requirements.

Where tests and analyses are performed by external labora-tories or third parties, these are to be recognised by RINA.

2.1.2 Approval Depending on the type and importance of the productsbeing supplied, the relevant manufacturing process may berequired to be approved and approval tests performed forthe purpose.

When approval of the manufacturing process is required,such condition is specified in the rule requirements relevantto the various products.

The provisions for the approval of Manufacturers are givenin the Rules for the approval of Manufacturers of materi-als.

2.1.3 ResponsibilityIrrespective of the interventions of Surveyors, the Manufac-turer is entirely and solely responsible for compliance of thesupplied products with the stipulated requirements.

RINA assumes no liability by its testing interventions inrespect of the compliance of a tested product with the stipu-lated regulations and requirements.

Where, in the course of manufacture or after supply, a prod-uct is found not to be in compliance with the requirementsor to present unacceptable defects, it will be rejected, irre-spective of any previous satisfactory test results.

2.2 Chemical composition

2.2.1 The chemical composition is to be determined andcertified, as a rule, by the Manufacturer using ladle sam-

Pt D, Ch 1, Sec 1


pling analysis. The laboratory is to be adequately equippedand the analyses are to be performed by qualified person-nel.

2.2.2 The analyses of the Manufacturer are generallyaccepted subject to occasional checks, if required by theSurveyor. When checks on the product are required, theyare to be performed and the results evaluated in accordancewith recognised standards.

2.3 Condition of supply

2.3.1 Unless otherwise agreed, the products are to be sup-plied in the finished condition as per rules, including heattreatment if required.

Heat treatment is to be carried out in suitable and efficientfurnaces, fitted with appropriate means for temperaturecontrol and recording.

The furnaces employed are to have a size sufficient to allowa uniform increase in temperature up to the required valueof the whole furnace charge to be heat treated. In the caseof very large parts, alternative systems proposed are to beagreed by RINA.

Sufficient thermocouples are to be connected to the furnacecharge to measure and record its temperature and checkthat it is adequately uniform, unless the temperature uni-formity of the furnace is verified at regular intervals.

2.4 Identification of products

2.4.1 In the course of manufacturing, inspection and test-ing, the identification of the various products in respect oftheir origin is to be ensured as required.

To this end the Surveyor is to be given all facilities for trac-ing the products when required.

3 Inspection and testing

3.1 General conditions

3.1.1 As a rule, the inspections and tests are to be carriedout at the Manufacturers works before delivery.

If the necessary facilities are not available at the Manufac-turers works, the testing is to be carried out at a recognisedtesting laboratory.

3.1.2 Where the testing is allowed to be carried out orcompleted at works other than the Manufacturers it is inany case to be possible to trace back with certainty to thedocumentation of the origin.

3.1.3 Interested parties are to apply for inspection in ade-quate time.

Prior to the inspection and testing, the Manufacturer is toprovide the Surveyor with details of the orders, technical

specifications and any special condition additional to therule requirements.

3.1.4 The Surveyors are to have free access to all depart-ments involved in production, collection of test samples,internal control and, in general, all operations concerningthe inspection.

They are to be supplied with the information necessary toassess whether production and tests are performed accord-ing to the rule requirements.

3.1.5 All tests and checks required by the Rules are to becarried out in the presence of the Surveyors or, whenexpressly agreed with RINA, in the presence of the personresponsible for internal control, specially delegated for thispurpose.

The inspection and testing activities may be delegated to theManufacturer under the conditions given in [3.2].

3.1.6 The tests required are to be performed by qualifiedpersonnel in accordance with the procedures stated byRINA or, failing this, with recognised national or interna-tional standards.

The testing and measuring equipment is to be adequate,maintained in proper condition and regularly calibrated, asrequired; the record of such checks is to be kept up-to-dateand made available to the Surveyor.

3.2 Alternative inspection scheme

3.2.1 Alternative procedures to the systematic interventionof the Surveyor for testing may be adopted by Manufactur-ers specially recognised by RINA for the purpose.

Such alternative inspection schemes, which are determinedby taking into account the type of product, its mass produc-tion and the effectiveness of the certified Quality Systemimplemented in the workshop, allow the testing operationsindicated in these Rules to be totally or partially delegatedto the Manufacturer.

Indications on the field of application of such schemes,along with conditions and procedures for their recognition,are given by RINA in a separate document.

3.3 Sampling for mechanical tests

3.3.1 The test samples are to be selected by the Surveyoror by a responsible person from the Manufacturer's staff,specially delegated, and are to be suitably marked for iden-tification purposes.

3.3.2 The test samples are to be representative of the unitor lot of material which they are relevant to and are there-fore also to have been subjected to the same heat treatmentas the products except when a different procedure is agreedwith RINA.

Pt D, Ch 1, Sec 1


3.3.3 For the purpose of test sampling the following defini-tions apply:

a) unit: single forging, casting, plate, tube or other singleproduct

b) rolled unit: product rolled from the same slab or billetor, when rolling proceeds directly from ingots, from thesame ingot

c) batch: number of similar units or rolled units presentedas a group for acceptance testing, on the basis of thetests to be carried out on the test sample

d) sample: a sufficient quantity of material taken from theunit, rolled unit or batch, for the purpose of producingone or more test specimens

e) test specimens: part of sample with specified dimen-sions and conditions for submission to a given test.

3.4 Mechanical tests

3.4.1 The mechanical tests are to be carried out in thepresence of the Surveyor unless otherwise agreed; see [3.2].

3.4.2 For the check of the mechanical properties of thematerial, test methods and specimens in compliance withthe requirements of Sec 2 are to be used.

3.4.3 The type of tests, the number and direction of the testspecimens and the results of the tests are to comply with therequirements relevant to the type of product, as indicated inthe various Articles.

3.5 Re-test procedures

3.5.1 GeneralWhere the unsuccessful outcome of any test is attributableto defective machining of the test specimen and/or toimproper test procedure, the negative result is disregardedand the test repeated, in correct conditions, on a substitutetest specimen.

Where a test, other than an impact test, gives a result whichis not in compliance with the requirements, two additionaltests may be allowed to be performed on specimens of thesame type taken from the same samples. For the purpose ofacceptance, both tests are to comply with the requirements.

For the impact test, performed on a set of three test speci-mens, where the average value of the set does not complywith the required value, provided that not more than twotest results are less than such value, with not more than oneless than 70% of it, a second test may be allowed to be per-formed on three test specimens of the same type taken fromthe same samples.

For acceptance, the new average, calculated on the basis ofthe six results of the first and second sets of three test speci-mens taken together, is to comply with the required value,not more than two individual values are to be lower thanthe required average and, of these, not more than one is tobe less than 70% of it.

3.5.2 Rejection or reconsiderationWhere unsatisfactory results are obtained from re-tests rep-resentative of one lot of material, the unit from which thetest specimens are taken is rejected.

The remainder of the lot may, at the discretion of the Sur-veyor, be reconsidered by performing the required tests onat least two different units; for acceptance, both the resultsof the new tests are to satisfy the requirements.

Otherwise, upon agreement with the Surveyor, the individ-ual units composing the lot may be tested individually andthose found satisfactory may be accepted.

The Manufacturer may resubmit for testing previouslyrejected material, after a suitable heat treatment or reheattreatment, or resubmit it under a different grade.

The Surveyor is to be notified of such circumstances.

Unless otherwise agreed by the Surveyor, only one newheat treatment is permitted for material which has alreadybeen heat treated.

3.6 Visual and dimensional examinations and non-destructive tests

3.6.1 GeneralThe products are to be subjected to:

a) visual examination

b) dimensional check

c) non-destructive examination, when applicable.

The above operations, to be effected on products in appro-priate conditions, are carried out under the responsibility ofthe Manufacturer and are to be witnessed or repeated in thepresence of the Surveyor when required by the Rules or, inany case, when it is deemed necessary by the Surveyor.

When, following examinations and tests, there are groundsfor thinking a product may be defective, the Manufacturer isobliged, for the purpose of acceptance, to demonstrate itssuitability using procedures deemed necessary.

3.6.2 Visual examinationVisual examination, unless otherwise specified, is per-formed by the Surveyor on each unit, for products tested onindividual units and, randomly or on the units submitted tomechanical tests, for products tested by lot.

3.6.3 Dimensional checkThe dimensional checks and verification of compliancewith approved plans are carried out by the Surveyor, asdeemed necessary, solely for those parts subject toapproval, or where expressly required in Part D or otherparts of the Rules.

3.6.4 Non-destructive testNon-destructive test is to be performed by operators quali-fied according to a national recognised scheme with agrade equivalent to level II qualification of ISO 9712, SNT-TC-1A, EN 473 or ASNT Central Certification Program(ACCP). Operators qualified to level I may be engaged inthe tests under the supervision of personnel qualified tolevel II or III. Non-destructive test is to be performed usingcalibrated equipment of suitable type and according toapproved procedures, recognised standards and therequirements of RINA. Personnel responsible for the prepa-ration and approval of NDT procedures are to be qualifiedto a grade equivalent to level III of ISO 9712, SNT-TC-1A,EN 473, ACCP or ASNT.

Pt D, Ch 1, Sec 1


The Manufacturers laboratory or other organisation respon-sible for the non-destructive test is required to issue, on itsown responsibility, a certificate illustrating the results and,where requested, an opinion concerning the acceptabilityof the product; in the latter case, the certificate is to becountersigned by the Manufacturer.

Personnel qualifications are to be verified by certification.Personnel certificates are to be issued by RINA, by anotherIACS Society or by a recognised third party body.

For the radiographic test suitable means are to be providedin order to identify the zones examined and the relevantradiographic films.

The various steps of the examinations are to be witnessedby the Surveyor when required. In such case the certificatesare generally to be countersigned by the witnessing Sur-veyor.

The radiographic examination is intended to be carried outby using X-ray. The use of gamma-ray may be accepted pro-vided that it is demonstrated to RINA's satisfaction that thisprovides the same image quality as X-ray.

3.7 Repairs of defects

3.7.1 Small surface defects may be suitably removed bygrinding or other appropriate means, provided that thedimensional tolerances, prescribed for the various productsin the relevant Articles, are complied with.

The repaired zone is to be found free from defects and to beacceptable in the opinion of the Surveyor.

3.7.2 Repairs by welding may be accepted only where thisis not in contrast with the requirements applicable to theproduct, and provided that they are deemed suitable inconnection with the material, extent of defects and weldingprocedure.

The repair procedure is to be previously agreed upon withthe Surveyor.

4 Identification and certification

4.1 Identification and marking

4.1.1 General During the inspection, a detailed record of the products tobe tested is to be submitted to the Surveyor with indicationof the necessary data, as applicable:

a) name of purchaser and order number

b) hull number or destination

c) number, size and mass of parts or batches

d) cast number and chemical composition

e) part reference number, detail of manufacturing processand heat treatment

f) condition of supply.

4.1.2 Manufacturers marking Products, which have satisfactorily undergone the requiredinspection and tests are to be appropriately marked by theManufacturer in at least one easily accessible location.

The marking is to contain all necessary indications, as spec-ified in the Articles relevant to the various products, and isto correspond to the content of the inspection documenta-tion.

The marks are to be stamped, as a rule, by means of brands,except when products could be impaired by such a system.When paints or other reliable alternatives are adopted, ade-quate duration of marking is to be ensured.

For small pieces contained in effective containers, as wellas bars and sections of modest weight, adequately bound inbundles, the marks are transferred to the container, label ortop item of each bundle to the Surveyors satisfaction.

4.1.3 Marking with RINAs brand The products satisfactorily inspected in accordance with theRules are to be marked with RINAs brand in the presence ofthe Surveyor unless otherwise agreed between Manufac-turer and Surveyor.

All other additional marks required are specified in theapplicable Articles depending on the products (e.g. name orinitials of Manufacturer, material, grade and cast number,code for calendar year, running file number and code of thelocal office inspection, Surveyors personal brand, TP asstatement of hydrostatic test).

4.1.4 Society marking for incomplete inspectionWhenever a product is despatched for delivery or is to bemarked without undergoing all the inspections and testsrequired (whether by the provisions of Part D or those ofother parts of the Rules), RINAs brand will be replaced byRINAs mark for incomplete inspection.

The testing documents are to contain clear indications of alloutstanding inspections and tests and specify the reasonwhy they have not been performed.

Upon satisfactory completion of all required tests, the prod-uct is to be stamped with RINAs brand.

4.1.5 Invalidation of Societys brand When a product already marked with one of RINAs stampsis found during or subsequent to the testing not to be incompliance with the requirements and is therefore rejected,the previously stamped marks are to be invalidated bypunching them.

The Surveyors may request to check the invalidationeffected.

Any repairs after the product is tested are subject to theprior consent of RINA; failing this, the validity of the origi-nal testing will automatically expire and the original testingmarks are to be invalidated by the interested parties.

4.1.6 Societys brand for alternative inspection scheme

In the case of admission to an alternative inspectionscheme, the marking with RINAs brand may be delegatedto the Manufacturer, who will be supplied with the specialbrand to be used for this purpose.

Pt D, Ch 1, Sec 1


4.2 Documentation and certification

4.2.1 Societys inspection certificate For products tested with satisfactory results, RINA issues aninspection certificate signed by the Surveyor stating that theproducts have been tested in accordance with RINAs Rules.

This certificate is identified by the letter C for ease of refer-ence in the various parts of the Rules.

An inspection certificate issued by the Manufacturer is to beattached to RINAs certificate and is to include, as applica-ble, the following particulars:

a) Manufacturers name

b) purchasers name, order number and hull number

c) description of the product, dimensions and weight

d) results of all specified inspections and tests, includingnon - destructive tests where applicable

e) identification and testing marks stamped on the prod-ucts.

In the case of testing of materials, the following particularsare also to be included:

identification of specification or grade of material

identification of the heat and relevant chemical analysis

supply condition and the specification of heat treat-ment, if carried out, including temperature and holdingtime

working and manufacturing procedure (for rolled prod-ucts intended for hull, boilers and pressure vessels only)

declaration that the material has been made by anapproved process, as applicable, and that it has beensubjected with satisfactory results to the tests requiredby the Rules.

By agreement with RINA, the inspection certificate issuedby the Manufacturer may be directly confirmed by endorse-ment with RINAs brand and the signature of the Surveyor.

For products manufactured in large quantities and tested byheats or by lot, the Manufacturer is to further state, for the

individual supplies, that the products have been producedaccording to RINAs Rules.

4.2.2 Societys inspection certificate for alternative inspection scheme

For products covered by the alternative inspection scheme,unless otherwise stated in the admission to the alternativeinspection scheme, the Manufacturer is to issue a Certificateof Conformity on the appropriate Society form.

This certificate is identified by the letter CA (certificate foralternative survey) for ease of reference in the various partsof the Rules.

The inspection certificate issued by the Manufacturer andincluding all the information required in [4.2.1] is to beattached to the (CA) certificate.

The certificate is to be submitted to RINA for endorsementaccording to the procedures stated in the agreement for thealternative survey scheme.

4.2.3 Works certificates

For products which in accordance with the relevant rulesmay be accepted only on the basis of a certificate of con-formity issued by the Manufacturer, stating the results of thetests performed, such certificate is to contain the informa-tion required under [4.2.1], as applicable.

This certificate of conformity is identified by the letter W(works certificate) for ease of reference in the various partsof the Rules.

For particular products it may be accepted that the tests orinspections are carried out by the Manufacturer not on theproduct supplied, but on the current production.

This particular certificate of conformity is identified by theletter R (report) for ease of reference in the various parts ofthe Rules.

Pt D, Ch 1, Sec 2


SECTION 2 TESTING PROCEDURES FOR MATERIALS

1 General

1.1 Application

1.1.1 This Section specifies the requirements for testingprocedures, testing machines and test specimens formechanical and technological tests of materials.

The testing procedures and test specimens relevant to weld-ing are specified in Chapter 5.

The Articles of the Rules, dealing with the various products,indicate the examinations and tests required together withthe results to be obtained.

The general conditions specified in Sec 1 also apply.

1.2 Testing machines

1.2.1 Testing machines are to be maintained in a satisfac-tory and accurate condition and calibrated by RINA, or by arecognised body in accordance with a recognised standard,at approximately annual intervals.

In particular:

The accuracy of tensile test machines is to be within 1% and when the calibration is in accordance with ISO7500-1 the permitted indication errors are to be withinthe specific values for Class 1.

Impact testing machines are to be calibrated in accord-ance with ISO 148-2 or other recognised standard.

The striking energy of the testing machine is to be not lessthan 150 J.

The records of the calibration are to be made available tothe Surveyor and kept in the test laboratory.

1.3 Preparation of test specimens

1.3.1 The samples for test specimens are to be in the samecondition as the product from which they have been takenand therefore in the same heat treatment condition, if any.

1.3.2 If the test samples are cut from products by flamecut, when admissible depending on the kind of material, orshearing, a reasonable margin is required to enable suffi-cient material to be removed from cut or sheared edges dur-ing final machining.

Test specimens are to be obtained from samples by mechan-ical cuts; care should be taken in their preparation to avoidany significant straining or heating which might alter theproperties of the material.

2 Tensile test

2.1 Test specimens

2.1.1 Proportional flat specimenFor flat products, rectangular specimens of proportionaltype are generally used, having dimensions as shown inFig 1.

Figure 1 : Proportional flat specimen

b tROriginal

Cross-sectional area So

Lo original gauge length

Lc parallel length

t : thickness of the considered materialb : 25 mm (width)Lo : 5,65S01/2 where So is the specimen original cross sectional area. The gauge length

may be rounded off the nearest 5 mm provided that the difference between the computedLo and that rounded length is less than 10% of Lo

Lc : Lo + 2S01/2R : 25 mm (transition radius)

Pt D, Ch 1, Sec 2


For such products the tensile test specimens are to retain theoriginal raw surfaces of the product.

When the testing machine capacity does not allow testingof specimens of full thickness, this may be reduced bymachining one of the raw surfaces.

2.1.2 Non-proportional flat specimenAs an alternative to the specimen mentioned above, non-proportional specimens may also be used; in particular arectangular specimen, having fixed gauge length of 200 mmand other dimensions as shown in Fig 2, may be used.

2.1.3 Round specimenAs stated in [2.1.1], for rolled products, excluding bars, thetensile test specimens are to retain the original raw surfacesof the product.

However, for thickness equal to or greater than 40 mm, or,more generally, when the testing machine capacity does notallow testing of specimens of full thickness, a round propor-tional test specimen, machined to the dimensions shown inFig 3, may also be used.

For long rolled products (bars and profiles), forgings andcastings, grey cast iron excluded, cylindrical specimens ofproportional type, having in general diameter of 10 or 14mm, are to be used.

2.1.4 Round specimen diameter The proportional round tensile specimens generally havediameter of 10 or 14 mm.

However others diameters, in general 8 or 6 mm, may beused in specific cases when the selection of normal size testspecimens is not possible.

2.1.5 Round specimen positionIn the case of rolled products (plates), with thickness equalto or greater than 40 mm, the axis of the round test speci-men is to be located at approximately one quarter of thethickness from one of the rolled surfaces.

In the case of bars and similar products, the axis of theround test specimen is to be located at one third of theradius from the outside.

In the case of forged products, unless otherwise agreed, thelongitudinal axis of test specimens is to be positioned as fol-lows:

a) for thickness or diameter up to maximum 50mm, theaxis is to be at the mid-thickness or the centre of thecross section;

b) for thickness or diameter greater than 50mm, the axis isto be at one quarter thickness (mid-radius) or 80mm,whichever is less, below any heat treated surface.

Figure 2 : Non proportional flat specimen

Figure 3 : Round proportional specimen

tR 25 mm

L0 = 200 mm

Lc = 212,5 mm

b

t : thickness of the considered flat material

b : 25 mm

R = 10 mm (see Note 1)

d

Lo original gauge length

Lc parallel length (see Note 2)

Cross sectional area

Note 1: R 1,5 d for nodular cast iron and materials with a specified elongation less than 10%

Note 2: Lc = Lo + d/2

Pt D, Ch 1, Sec 2


2.1.6 Specimen for grey cast ironFor grey cast iron, the test specimen as shown in Fig 4 is tobe used.

Figure 4 : Specimen for grey cast iron

2.1.7 Specimens for pipes and tubes For testing of pipes and tubes, the testing specimen may bea full cross-section of suitable length to be secured in thetesting machine with plugged ends, as shown in Fig 5.

The gauge length L0 is to be equal to:

and the distance between the grips or between the plugs Lcis to be not less than the gauge length plus D/2, where D isthe external diameter of the tube or pipe.

The length of the plugs projecting over the grips, in thedirection of the gauge marks, is not to exceed the externaldiameter D, and the shape of the plugs is not to impede theelongation of the gauge length.

Figure 5 : Full cross section specimen

Alternatively test specimens are to be taken from the tube orpipe wall, as shown in Fig 6, where:

LC = L0 + 2 b

Figure 6 : Specimen taken from the tube or pipe wall

Where the wall thickness is sufficient to allow machining,the round specimen indicated in Fig 3 may be used, withthe axis located at the mid-wall thickness.

2.1.8 Specimen for wiresFor testing of wires, a full cross-section test specimen ofsuitable length is to be used.

The gauge length is to be 200 mm and the parallel testlength (distance between the grips) is to be 250 mm.

2.1.9 Dimensional tolerances The dimensional tolerances of test specimens are to be inaccordance with ISO 6892-84 or other recognised stand-ards as appropriate.

2.2 Testing procedure

2.2.1 GeneralThe following characteristics, as required by the differentproducts, are to be determined by the test:

a) ReH : Yield stress (yield point), in N/mm2

b) Rp0,2 - Rp1,0 : Proof stress (yield strength), in N/mm2

c) Rm : Tensile strength, in N/mm2

d) A: Percentage elongation at fracture

e) Z: Percentage reduction of area.

2.2.2 Yield and proof stress determinationFor materials with well defined yield phenomenon, theyield stress ReH is the value corresponding to the first stop or

drop of the index, showing the load applied by the testingmachine in the tensile tests at ambient temperature.

This applies, unless otherwise specified, to products of car-bon steels, carbon-manganese steels and alloy steels,except austenitic and duplex stainless steels.

For materials which do not present a manifest yield stress,as defined above, the 0,2% proof stress (Rp0,2) is to be deter-

mined according to the applicable specification, where 0,2is the percentage of permanent deformation.

For austenitic and duplex stainless steel products and rele-vant welding consumables, the 1,0 per cent proof stress,designated by the symbol Rp1,0 , may be required in addi-

tion.

2.2.3 Load application rate The test is to be carried out with an elastic stress within thelimits indicated in Tab 1.

After reaching the yield or proof load, for ductile materialthe machine speed during the tensile test is not to exceed

that corresponding to a strain rate of 0,008s-1. For brittlematerials, such as cast iron, the elastic stress rate is not to

exceed 10 N/mm2 per second.

Table 1

2.2.4 ElongationThe per cent elongation is in general determined on a pro-portional gauge length Lo.

Lo is determined by the following formula:

where:

R 25 mm

20 mm dia.

Lo 5 65 So,=

t

LL

0

C Drift

D

Lo 5 65 So,=

R 10 mm

b 12 mmLo

Lc

So

Modulus of Elasticity of the material (E),

in N/mm2

Rate of stressing, in N/mm2 s-1

Min. Max.

E < 150000 2 20

E 150000 6 60

Lo 5 65 So,=

Pt D, Ch 1, Sec 2


So : Original cross-sectional area of the test speci-

men.

In the case of round solid specimens, L0 is 5 diameters.

The per cent elongation is also defined as short proportionalelongation or A5.

When a gauge length other than Lo is used, the equivalentper cent elongation Ax required is obtained from the follow-

ing formula:

Ax :

where:

A5 : Minimum elongation, in per cent,

required by the Rules for the pro-portional specimens illustrated inFig 1, Fig 3 and Fig 6

S : Area, in mm2, of the original cross-section of the actual test specimen

L : Length, in mm, of the correspond-ing gauge length actually used.

The above conversion formula may be used only for non-cold formed ferritic products with tensile strength not

exceeding 700 N/mm2.

The extension of the formula to other applications, such ascold worked steels, austenitic steels or non-ferrous materi-als is to be agreed upon with RINAs Surveyors.

In the case of disagreement, the value of elongation com-puted on the proportional specimen is to be taken.

The gauge length to which the elongation is referred is to beindicated in the test reports.

For non-proportional test specimens with gauge length of50 mm and 200 mm, the equivalent elongation values indi-cated in ISO 2566 apply.

The elongation value is, in principle, valid only if the dis-tance between the fracture and the nearest gauge mark isnot less than one third of the original gauge length. How-ever, the result is valid irrespective of the location of thefracture if the percentage elongation after fracture is equalto or greater than the expected value.

The appearance of the fracture of test specimens after thetensile test is always to be examined. The appearance of thefracture section is to be sound and free from defects andirregularities.

2.2.5 Testing at elevated temperature For testing at elevated temperature, the determination of 0,2per cent proof stress is to have a gauge length for strainmeasurement not less than 50 mm and a cross- sectional

area not less than 65 mm2. However, if the dimensions ofthe product or the available test equipment do not allowsuch conditions, the largest possible dimension is to beused.

As yield stress the conventional value of 0,2 per cent proofstress is generally taken; the deformation rate immediatelyprior to reaching the yield stress is to be in the rangebetween 0,1 and 0,3 per cent of the gauge length perminute.

The intervals between deformation measurements to assessthe above-mentioned rate are not to exceed 6 seconds.

The equipment is to permit a test temperature control withina tolerance range 5C.

2.2.6 Re-test procedure When the tensile test fails to meet the requirements, twofurther tests may be made from the same piece.

If both of these additional tests are satisfactory, the itemand/or batch (as applicable) is acceptable. If either or bothof these tests fail, the item and/or batch is to be rejected.

The additional tests detailed above are preferably to betaken from material adjacent to that for the original tests,but alternatively from another test position or sample repre-sentative of the item/batch.

3 Bend test

3.1 Flat bend test specimen

3.1.1 A flat bend test specimen as shown in Fig 7 is to beused.

The edges on the tension side are to be rounded to a radiusof 1 to 2 mm.

The length of the specimen is to be at least 11 times thethickness or 9 times the thickness plus the mandrel diame-ter, if this value is higher.

Figure 7 : Flat bend specimen

3.1.2 For castings, forgings, and half rough products, theother dimensions are to be as follows:

thickness: t = 20 mm,

width: w = 25 mm.

3.1.3 For rolled products the other dimensions are to be asfollows:

thickness: t = thickness of product,

width: w = 30 mm.

If the thickness of the rolled product is greater than 25 mm,the thickness of the specimen may be reduced to 25 mm bymachining the surface of the specimen that is to be in com-pression during the test.


3.2.1 The bend test is to be performed, as a rule, by apply-ing a continuous mechanical compressive action on one ofthe surfaces of the test specimen.

2A5S

L-------

0 4,

w

t

1 to 2 mm 1 to 2 mm

Pt D, Ch 1, Sec 2


The required mandrel diameter and the minimum bend

angle are specified in the Articles dealing with the various

products.

The test is satisfactory if the required bend angle is reached

without incipient fracture.

4 Impact test

4.1 Sampling

4.1.1 The impact test is, in general, to be determined on aset of 3 notched specimens.

The longitudinal axis of the notched test specimens can be:

a) parallel to the rolling direction of the plate, of the sec-

tion, or of the piece (longitudinal direction L)

b) perpendicular to the rolling direction of the plate or of

the piece (transverse direction T)

c) parallel to other directions of selection.

The test specimens are to be of the V-notch type and are

designated KV.

Depending on whether the Charpy test specimens have

been taken in the lengthwise direction (L) or in the cross-

wise direction (T), the symbol L or T is added, respectively,

to the Charpy designation.

4.1.2 The axis of the notch is to be perpendicular to thefaces of the plate, section or piece.

The position of the notch is to be not nearer than 25 mm to

a flame cut or sheared edge.

4.1.3 For rolled products, the impact test specimens are tobe taken, in the case of thickness not higher than 40 mm,

retaining the original raw surface of the product or within

2mm from it.

In the case of thickness higher than 40 mm, the test speci-

mens are to be taken with their longitudinal axis located at

a position lying 1/4 of the product thickness, or as near as

possible to such position.

For forged products, the longitudinal axis of the specimens

is to be located in the way of the external third of the dis-

tance between the centre (or the inside surface) of the piece

and its external surface, considering a typical section of the

forging.

4.2 Charpy V-notch specimens

4.2.1 The specimens are to be fully machined at thedimensions and tolerances shown in Fig 8 and Tab 2.

Figure 8 : Charpy V-notch specimen

Table 2 : Charpy V-notch specimen

4.2.2 Specimens with reduced sectional area 10x7,5 or10x5 may be used when the product thickness does not per-mit machining of the standard size.

All other dimensions and tolerance are to be as specified in[4.2.1].

In all cases the largest size Charpy specimen possible forthe material thickness is to be machined.

The required energy values are given in Tab 3.


4.3.1 Tests on V-notch type specimens are to be carriedout at or below ambient temperature, in compliance withthe requirements of the parts of the Rules relevant to theindividual products and uses.

The term "ambient temperature" means any temperaturewithin the range 18 to 28C.

Where the test temperature is lower than ambient, the tem-perature of the specimen at the moment of the breaking isto be the specified test temperature, within plus minus 2C.

The test temperature is to be clearly specified in the testingdocuments.

Dimensions Nominal Tolerance

Length 55 mm 0,60 mm

Width

standard specimen 10 mm 0,11 mm

subsize specimen 7,5 mm 0,11 mm

subsize specimen 5,0 mm 0,06 mm

Thickness 10 mm 0,06 mm

Depth below notch 8 mm 0,06 mm

Angle of notch 45 2

Root radius 0,25 mm 0,025 mm

Distance of notch from end of test specimen

27,5 mm 0,42 mm

Angle between plane of sym-metry of notch and longitudinal axis of test specimen

90 2

8

27,5 27,5

10

10

55

45

V = notch sectionr =

0,25

Pt D, Ch 1, Sec 2


Table 3 : Average energy value for reduced specimens

4.3.2 For impact tests carried out on a set of three speci-mens, the Charpy impact toughness is the average adsorbedenergy, expressed in Joule (J), resulting from the set.

The average of the results on the three specimens is to com-ply with the value required for the product in question, andone individual test result may be less than the required aver-age value, provided that it is not less than 70% of it.

4.4 Re-test procedure

4.4.1 Where specified the following Charpy re-test proce-dure will apply.

When the average value of the three initial Charpy V-notchimpact specimens fails to meet the stated requirement, orthe value for more than one specimen is below the requiredaverage value, or when the value of any one specimen isbelow 70% of the specified average value, three additionalspecimens from the same material may be tested and theresults added to those previously obtained to form a newaverage. If this new average complies with the requirementsand if not more than two individual results are lower thanthe required average and of these, not more than one resultis below 70% of the specified average value, the piece orbatch (as specified for each product) may be accepted.

5 Drop weight test

5.1 Definition and specimens dimensions

5.1.1 The drop weight according to ASTM Standard E 208is used for determination of the NDT (nil ductility transition)temperature.

The NDT is the maximum temperature where the dropweight specimen breaks when tested according to the pro-visions of the standard.

Drop weight specimens have one of the following dimen-

sions (thickness by width by length, in mm3):

a) type P1: 25 x 90 x 360

b) type P2: 19 x 50 x 130

c) type P3: 16 x 50 x 130.

5.1.2 The following apply, if not otherwise agreed:a) the specimen sides are to be saw-cut or machined (min-

imum 25 mm distance to flame-cut surface)

b) the machining of the sample to obtain the requiredthickness of the specimen is to be carried out only onone surface; the opposite mill scales surface is to bemaintained

c) the direction of the specimen in relation to the rollingdirection is not importanct, but all the specimens of thesame test series are to have the same orientation.


5.2.1 Two test specimens are to be tested at the specifiedtest temperature.

The compression side is to be on the machined side.

Both test specimens are to exhibit no-break performance atthe specified temperature.

6 CTOD test (crack tip opening dis-placement test)

6.1

6.1.1 Unless otherwise agreed, the test is to be performedon specimens of full section thickness according to nationalor international standards.

Note 1: Internationally accepted standards include BS 7448 Part1:1991 and ASTM E 1290 1989.

6.1.2 Other fracture mechanics tests intended to check theresistance to brittle fracture of the material may be carriedout as required by RINA.

7 Ductility tests for pipes and tubes

7.1 Flattening test

7.1.1 The specimen consists of a ring cut with the endsperpendicular to the axis of the pipe or tube.

The length of the specimen is to be from 10 mm to 100 mm;alternatively, a fixed length of 40 mm may be accepted.

The edges of the test pieces are to be rounded by filingbefore the test.

7.1.2 The test consists of compressing the specimenbetween two rigid and parallel flat plates in a direction per-pendicular to its longitudinal axis; the plates are to coverthe whole specimen after flattening.

It is to be continued until the distance Z between the twoplates, measured under load, reaches the value specified.

In the case of welded pipes or tubes, the test is to be carriedout with the welded seam positioned

propeller shaft requirements

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