MULTI LAYER PIPE AND PRESS-FITTINGS

ISO 9002SQP

C ER TIFIE D

ISO 9002

CO

MPA

NY QUALITYSYST

EMSQP

MULTI LAYER PIPE AND PRESS-FITTINGS

MULTI LAYER PIPE FOR WATER SUPPLYAND HEATING SYSTEMS

PRANDELLI s.r.l. via Rango, 58 - 25065 Lumezzane (Bs) Italia Tel. +39 0308 920 992 - Fax +39 0308 921 739

www.prandelli.com e-mail:prandelli@prandelli.com

3

CHAPTER 1

CHAPTER 2

CHAPTER 3

CHAPTER 4

CHAPTER 5

CHAPTER 6

CHAPTER 7

CHAPTER 8

CHAPTER 9

CHAPTER 10

- GENERAL FEATURES OF THE SYSTEM - page 5

IntroductionDescription of the systemFields of application

- MAIN CHARACTERISTICS OF THE SYSTEM - page 8

- GUARANTEE - page 10

- DIMENSIONAL CHARACTERISTICS page 11

- TECHNICAL GUIDELINES - page 12

Operating conditionsLoss of pressureExpansion

- THE INSTALLATION TECHNIQUE - page 17

- PROCESSING - page 20

- RESISTANCE TO CHEMICALS - page 23

- PRECAUTIONS - page 26

- TESTING OF THE INSTALLATION - page 29

EDITION 3 - 07/02

Contents

Introduction

DESCRIPTION OFTHE SYSTEM: THE PIPE

The MULTYRAMA System is a system of pipes and fittings suitablefor the construction of water supply and heating systems.

The system features a pipe produced with cutting edge technologies,which combines and fully exploits the properties of plastic andmetal.

In fact, this is a multi-layer pipe, comprising two layers of cros-slinked polyethylene, bonded to an intermediate layer of alumi-nium.

The joints are made using mechanical compression unions, of boththe “Press-fitting” and nut and ring tightening type.

The resistance properties of the MULTYRAMA System, as well as therange of sizes available, allow the installation engineer to createsystems of various types, primarily for water supply and heating.

As mentioned above, the MULTYRAMA pipe consists of two mate-rials of different nature, with very different characteristics, whichhowever combine to form a product with very interesting properties.

5

Inside pipe in PE-X

Outside pipe in PE-X

Adhesive

Adhesive

Intermediate layerof aluminium

Chap. 1

6

THE FITTINGS

The inner pipe, which is in direct contact with the conveyed fluid, ismade of crosslinked polyethylene (PE-X). This is covered with asheet of aluminium, head-welded using a laser beam (type Aaccording to UNI 10954-1). In turn, the aluminium is covered withcrosslinked polyethylene and the three layers are joined togetherusing suitable adhesive.

The unions of the MULTYRAMA System “Press-Fitting” type achieveseal by conforming the pipe on the hose connector of the union bymeans of press-fitting on the metal bush, while the nut and ringtightening type feature a nut on a metal ring. In both cases the hoseconnector, to which the pipe is fitted on assembly, is shaped so as toensure a perfect seal between the parts after the pressing operation,preventing any possibility of leaks.

The hose connection onto which the pipe is fitted during assembly isshaped to allow a perfect seal between the parts during compression,preventing all possible leakage points. The profile of the hose con-nection also has a seat containing an O-ring, which further enhancesthe hydraulic seal.

A cross-section CM pipe-union joint

A cross-section of the pipe-fitting joint

Chap. 1

7

To prevent triggering dangerous electrochemical processes betweenthe metals of the union and pipe, due to any contact once the unionhas been fitted, suitable O-ring spacers have been positioned at thebase of the hose connector, against which the pipe rests.These O-rings also ensure the pre-fitting of the metal bushes for thePress-Fitting type.

The MULTYRAMA System unions are made of brass and the bodyand pipe clamp ring feature a nickel-plated surface. In the event ofthe Press-fitting being removed, always be careful to fit the pipe inthe bush and make sure this is secured to the O-ring at the base ofthe hose connector, then push the pipe all the way.

Its resistance to thermal and mechanical stresses makesMULTYRAMA suitable for carrying pressurized hot and coldfluids in general, for long periods of time.

As provided by UNI 10954-1 standard, the transport is allowed ofwater for domestic purposes and in this sense the MULTYRAMAcomplies with all fundamental hygiene regulations. Heating, conditioningand numerous other types of installation can also be made for:

- convey compressed air

- convey spa or saline water

- convey edible fluids

- convey industrial fluids

FIELDS OF APPLICATIONE

Chap. 1

8

Thanks to its dual nature, MULTYRAMA multi-layer pipe offers theinstaller the benefits of plastic combined with those of metal, asdescribed below.

Since the fluid is in direct contact with PE-X, both acid and alkalinesubstances can be carried, as well as edible fluids and drinking water(in all cases, when special substances are to be conveyed users areadvised to contact our company directly).

The PE-X outer coating prevents the materials normally used in buil-ding (lime or cement) from triggering processes which would corrodethe metal part of the pipe.

The extremely smooth inside surface of the pipe minimizes the conti-nuous loss of pressure (see graphs on pages 31-32), considerablyreducing the risk of blocked pipes due to scale.

PE-X is an excellent thermal insulator and also gives this property toMULTYRAMA pipe, allowing energy saving when hot water is carried,as the losses of heat from the conveyed fluid are minimal. The ther-mal conductivity of MULTYRAMA is just 0.43 W/mK.

The crosslinked polyethylene which forms the inside layer of theMULTYRAMA pipe meets the hygiene standards required for thetransport of edible fluids and drinking water.

The density of plastics in general, and of polyethylene in particular,makes the pipe extremely light, allowing easy handling both duringtransport and storage and during installation.

The two layers of PE-X considerably attenuate the noise generatedby the fluid flowing through the pipe, both at high flow-rates and whenwater hammers are present.

THE ADVANTAGESOFFERED BY PE-X

RESISTANCE TOAGGRESSIVE FLUIDS

RESISTANCE TO CORROSION

SMOOTH, COMPACTSURFACE

LOW THERMALCONDUCTIVITY

HYGIENE

LIGHT WEIGHT

LOW NOISE

Chap. 2

9

The aluminium layer offers the considerable advantage that theMULTYRAMA pipe can be shaped with great ease. What's more, thisshape is maintained, allowing the installation to follow the requiredlaying route without using intermediate unions. It is also possible tocreate tight bends (see table "Pipe curvature table"), without causingexcessive variations in the pipe's cross section area.

The strength of the aluminium gives the pipe greater stability from thedimensional point of view, making any crushing due to external stres-ses less likely.

The composite pipe has a low linear expansion coefficient (0.026mm/m°C), especially advantageous when the product is installed inview and not sunk into walls or floors, and when there are large varia-tions in temperature.

The aluminium prevents any diffusion of oxygen through the wall ofthe pipe, making it completely impermeable to this gas.

The individual characteristics of the materials which make upMULTYRAMA are enhanced in the finished product, benefiting fromsynergies which create a pipe that is extremely easy to use, conve-nient in tricky situations, safe and durable over time.

THE ADVANTAGESOF ALUMINIUM

WORKABILITY

DIMENSIONALSTABILITY

LOW LINEAR EXPANSION

OXYGEN BARRIER

In conclusion

Chap. 2

10

The production of MULTYRAMA and its compo-nents is subjected to the most severe quality con-trols. The production cycle includes daily chemicaland physical inspections and continuous controlson the dimensions and surface, as well as checksthat the pipe walls are undamaged. Consequently, the following GUARANTEE, cove-red by a policy with a major insurance company, isprovided for MULTYRAMA when used for heatingand water supply systems, and for any other typeof installation, in a manner compatible with thetechnical characteristics of the product and inaccordance with the installation instructions in thispublication.

1. Through insurance cover with a leadinginsurance company, Prandelli, manufacturer ofMULTYRAMA, will compensate injury ordamage caused by breakage of pipes andfittings due to obvious manufacturing defects upto a maximum of 500.000,00 ¤, for a periodof 10 YEARS after the production date markedon the pipe.

2. The conditions governing this GUARANTEEare:

a) the pipe must be installed in accordance withthe installation instructions provided by us,further to checking for possible faults ortampering which have occurred afterproduction due to accidental causes.

b) The operating conditions (pressure andtemperature) must be within the technicallimits stated by the latest MULTYRAMAGuide.

c) The product must carry the MULTYRAMAidentification mark.

3. The GUARANTEE DOES NOT APPLY in thefollowing cases:

a) failure to comply with our recommendedinstallation instructions.

b) Connection of the pipe and fittings to heatsources with even accidental temperatureand pressure limits not compatible with thecharacteristics of the pipe.

c) Use of obviously unsuitable material (pipeswhich are old, scratched, etc.).

d) Use of one or more components notmanufactured by us in construction of thesystem.

4. INSTRUCTIONS FOR REQUESTING AFTER-SALES SERVICE UNDER GUARANTEE

In case of a breakage of MULTYRAMA duesolely to obvious manufacturing defects, usersmust send us a registered letter, sending a copyto their local agent. This letter must contain:

- date and place of installation;- specifications and identification mark of the

pipe; - information about the operating conditions

(pressure and temperature); - sample of the pipe on which the breakage

has occurred; - name and address of the installer who

constructed the system.

We will send a technician to check the causesof the breakage within a reasonable period oftime after receipt of this registered letter. If the breakage is covered by the terms of theGUARANTEE, we will put the matter in thehands of our insurance company, which will paycompensation after checking the cause andamount of the damage. If the breakage is not covered by the GUARAN-TEE, we will charge the expenses we haveincurred to the customer.

PRANDELLI s.r.l.

Chap. 3

11

MULTYRAMA pipe for water supply and heating plants.

See pages 33-34 for figures and dimensions of MULTYRAMA rangefittings.

DIMENSIONALTABLE OF MULTYRAMA

FITTINGS

Multyrama PE-X/AL/PE-X Pipe

Outside diameter mm

14

16

16

18

20

20

26

32

40

50

Thickness mm

2.0

2.0

2.25

2.0

2.0

2.5

3.0

3.0

3.5

4.0

Supplied in

rolls of 100 mt.

rolls of 100 mt.

rolls of 100 mt.

rolls of 100 mt.

rolls of 100 mt.

rolls of 100 mt.

rolls of 50 mt.or bars 4 mt.

bars 4 mt. or rollsof 50 mt.bars 4 mt.

bars 4 mt.

Chap. 4

12

Thanks to the resistance of the PE-X layer in direct contact with thefluid transported, the MULTYRAMA multi-layer pipe can be used inthe following operating conditions:

PRESSURE = 10 bar

TEMPERATURE = 70°C

TIME = 50 years

During its 50 year lifetime, the pipe is also able to withstand the maxi-mum temperature of 95°C for a total of 100 hours.

Since the fluid conveyed flows in contact with the PE-X, the loss ofpressure are especially low, due to the material's smooth surface.It should also be remembered that when water supply systems aredesigned it is possible to calculate a higher flow-rate than withsystems constructed from galvanized pipe, with no problems relatingto noise or surface abrasion.Pages 31 and 32 show the loss of pressure graphs for MULTYRAMASystem pipes.

The following is an example of calculation of loss of pressure relatingto the supply of water to a bathroom and a kitchen in a flat, with thefollowing layout.

OPERATING CONDITIONS

LOSS OFPRESSURE

Loss of pressurecalculation example

Chap. 5

13

The calculations have been made in accordance with UNI 9182-87with regard to the nominal flow-rates and the maximum simultaneousflow-rates of the individual users. The Load Unit method was thenapplied as described below.

Total N°7 0.9 11.50 4.50

The graph below shows the function which links Load Units and flow-rate. This function is used to establish the maximum simultaneousflow-rates.

We obtain:- maximum simultaneous cold water delivery rate = 0.57 l/s- maximum simultaneous hot water delivery rate = 0.29 l/s

N. of users

1 Washbasin1 Bidet1 W.C. with box1 Bath1 Dishwasher1 Sink1 Washing mach.

Nomin. flow-rate (l/s)(UNI 9182-87)

0.10.10.10.20.10.20.1

L.U. (UNI 9182-87)Cold water

0.750.753.001.502.001.502.00

L.U. (UNI 9182-87)Cold water

0.750.75

-1.50

-1.50

-

Chap. 5

14

We will now show how to calculate the system loss of pressure, con-sidering the horizontal section of pipeline, with the relative fittings.

With regard to localized loss of pressure, the following valuesare considered for the localized resistance coefficients "r":

The localized loss of pressure were calculated using the formula:z = 0.5 Σ v2 • r, while for continuous loss of pressure the graphs on

pages 31-32 were used, also considering them applicable to the sup-ply of hot water.

Fitting

90° Elbow

Union Tee

Tap

Coefficient r

1.5

2.0

2.0

Pipeline

1

23

45678

Multyramapipe

16X2.25

16X2.2516X2.25

16X2.2520X2.520X2.526X3.026X3.0

L.U.

2.00

3.501.50

3.507.0010.0010.7511.50

Max.simultaneousflow-rates l/s

0.20

0.260.18

0.260.350.500.540.57

Pipelinelength

m

2.0

2.02.5

2.51.52.51.51.5

Fittings present insection

1 tap2 elbows

1 tee1 tap

2 elbows1 tee1 tee1 tee1 tee1 tee

LocalizedLoss of P.

kPa

9.3

6.37.5

6.33.98.02.93.3

Unitary cont.loss of P.

kPa

4.6

7.54.2

7.53.66.72.22.4

Total Loss ofPressure ofpipeline kPa

18.5

21.318.0

25.09.324.76.26.9

Pipeline

1

2

345

Multyramapipe

16X2.25

16X2.25

16X2.2520X2.520X2.5

L.U.

1.50

1.50

3.003.754.50

Max.simultaneousflow-rates l/s

0.18

0.18

0.240.270.29

Pipelinelength

m

2.0

5.0

4.01.51.5

Fittings present insection

1 tap2 elbows1 rubin.2 elbows

1 tee1 tee1 tee

LocalizedLoss of P.

kPa

7.5

7.5

5.32.32.7

Unitary cont.loss of P.

kPa

4.2

4.2

6.72.42.6

Total Loss ofPressure ofpipeline kPa

15.9

28.5

32.15.96.6

129.9

89.0For the hot water section there is therefore a total loss of pressure (kPa)

For the cold water section there is therefore a total loss of pressure in kPa

Chap. 5

15

As already underlined, the layer of aluminium in the MULTYRAMApipe guarantees, amongst other properties, a low thermal expansionin the presence of large variations in temperature.This is important when the pipes have to be installed outside thewalls or floors and the installer has to adopt the necessary measuresto ensure that the system will not be damaged.

The expansion of the MULTYRAMA pipe is calculated by applying thefollowing formula:

∆L = α • L • ∆T where:

∆L = pipe expansion mm

α = linear expansion coefficient of the material mm/m°C:

MULTYRAMA = 0.026 mm/m°C

L = length of section of pipe free to expand m

∆T = difference between maximum operating temperature and the

ambient temperature on installation °C

To calculate the expansion ∆L of a section of MULTYRAMA pipeø 20x2.5, with length 8 m.

EXPANSION

Calculating theexpansion

EXAMPLE:

T amb = 20 °C (ambient temperature);T max = 70 °C (maximum operating temperature);L = 8 m;

from which we obtain

∆L = α • L • ∆T = 0.026 • 8 • (70-20) = 10.4 mm

Chap. 5

16

The expansion of MULTYRAMA can be calculated using the graphbelow.

Once the degree of expansion has been established, if the pipe is tobe installed outside the walls or floors it is necessary to create fixedand sliding supporting points, and in some cases expansionarms, to prevent damage to the pipe as a result of variations inlength.

Chap. 5

17

As already mentioned, the main applications for which the MULTY-RAMA System may be used are those relating to water supply andheating systems.

After checking that the system operating conditions cannot exceedthe maximum values the product is able to withstand, the pipes canbe laid following the instructions given below.

MULTYRAMA can be installed using different techniques:

a) with manifold

b) direct line

In water supplysystems

Chap. 6

18

The pipes may be installed:

in concrete:

- in this case, the pipe may come into direct contact with the concreteof the masonry which contains it, since there is no risk of corrosion(except for the metal fittings, which must be protected against corro-sion);

- if the pipe carries hot water, it must be suitably insulated to complywith the Law on the limitation of energy consumption;

- for installation under floors, the pipe should be laid on a bed of sandto prevent dangerous scratching of its surface;

visible:

- when installed on the outside of masonry structures, but inside thebuilding, pipes do not require any particular protection against expo-sure to U.V. radiation. However, sections installed outside buildingsshould always be protected;

- in case of large temperature variations, all appropriate precautionsshould be taken with regard to expansion of the pipe (see"Expansion");

- pipes must also be insulated if there is the risk that condensationmay form on their outside surface.

Here again, MULTYRAMA may be installed using the various techni-ques adopted in heating systems:

- with manifold

- single-pipe

- dual-pipe

In heating systems

Chap. 6

19

Pipes may be laid:

- in concrete

- visible, e.g. inside suitable guides such as perimeter strips ofthe skirting board type.

In both cases, the Law on the limitation of energy consumption mustbe complied with by insulating the pipelines as this law envisages.

When laying pipes outside the masonry, suitable supporting systemsmust also be used to allow for expansion.

The following radii of curvature must be complied with:

d = outside diameter of pipe.

CURVATURE OFPIPES

Pipe dimensionsmm

14 x 216 x 2

16 x 2.2518 x 220 x 2

20 x 2.526 x 332 x 3

40 x 3.550 x 4.0

Radius of curvat.without pipe

bending elbow

5.0 x d5.0 x d5.0 x d5.0 x d5.0 x d5.0 x d

----

Radius of curvat.with spring

2.5 x d2.5 x d2.0 x d2.5 x d3.0 x d3.0 x d

----

Radius of curvat.with pipe

bending elbow

------

5.0 x d5.0 x d≥ 8.0 x d≥ 8.0 x d

Chap. 6

20

The equipment needed to process MULTYRAMA pipes is as follows:

- pipe cutter tool, to make a precise cut free from burrs, without cau-sing deformations of the material. We advise against using shears.

- calibrator tool, to give the pipe its original cylindrical shape andsimplify insertion onto the fitting hose connection.

- Power or battery-driven pressing unit, with relevant pliers, forassembling the unions

- Manual pressing unit: only for ø 16 and 20

EQUIPMENT

Pipe cutter

Compression tool

Manual pressing unit

Calibrator

Chap. 7

21

MULTYRAMA pipes must be cut using the special tool with circularblade, which will provide a burr-free cut perpendicular to the pipeaxis. The use of cutting tools of other kinds may lead to undesirableovalization.

The tool is able to cut the various sizes of MULTYRAMA.

The next step is to calibrate the pipe which has just been cut, usingthe special tool. Insert the tool in the pipe, turning clockwise, until thetapered zone is reached.

After calibration, and before fitting the union, check that there are noprocessing residues such as shavings of material or dirt in generalinside the pipe.

PREPARING THEPIPE:cutting

calibration

Chap. 7

22

Once it has been determined that there are no traces of dirt on theunion O-rings, fit the pipe on the hose connector until this appearsfrom the inspection holes made in the metal bush, in the case of thePress-Fitting type. In the case of the tightening type, the pipe willhave to be pressed all the way on the hose connector.

Before pressing, make sure the different parts of the union, like theO-rings and metal bushes, are correctly positioned and that the pipeis properly fitted to the hose connector, that it is pushed all the wayand that the pressing unit pliers, besides being of the type and sizerequired, have one side resting against the body of the union.

ASSEMBLING THEFITTINGS

Warnings

Preparing the fitting Compression procedure

Compressed fitting Mechanical joint

Chap. 7

26

As already illustrated in this guide, MULTYRAMA offers many advan-tages from various points of view. However, in order to enjoy all thebenefits of these properties, the user must be well aware of everyaspect relating to the product to be used.

The following are a number of important recommendations essentialfor correct use of the MULTYRAMA system.

The use of MULTYRAMA in the stated operating conditions createsabsolutely no problems for the material.

However, exceeding the limit conditions for use may impair the pro-duct's resistance.

All precautions must therefore be taken to ensure that this does notoccur; this not only protects the system itself, but also its user.

MULTYRAMA can be installed in view, but inside buildings, withoutany need for special precautions to protect it.

However, installations involving prolonged, direct exposure to ultra-violet rays (sun, neon lamps) should always be avoided; in this case,the pipe must be adequately protected to avoid ageing of the externalPE-X, leading to loss of its initial chemical-physical characteristics.

Foreword

OPERATING CONDITIONS

ULTRAVIOLETRAYS

Chap. 9

27

Care must be taken to ensure that the pipe surface does not comeinto contact with sharp edges which may cut its surface and lead toshearing.

This factor must be borne in mind during both installation and stora-ge.

Pipes which have been accidentally scratched or scored must not beused.

MULTYRAMA must be bent in accordance with the minimum radiispecified (see "Laying technique" on page 19).

We recommend you always use the special tool and fit this inside thepipe, turning it and pushing it until you reach the tapered part thatcreates the chamfer inside the pipe. By doing so you will avoid anyrisk of dragging the O-ring on the hose connector with consequentunreliability of the joint. The gauge, devoid of the knob, can be fittedon the spindle of a drill to make the operation easier.

Users are advised to use the special tool with circular blade, whichallows cutting without burrs and perpendicular to the pipe's axis,without crushing. .

When using fittings with female thread, do not apply excessive tighte-ning torques when connecting to male fittings.

Also, take care not to place too much hemp between the parts to beassembled; teflon is to be preferred. In addition, check that the malepart is long enough for a proper connection; generally, at least oneturn of thread should be left free.

If installation requirements mean that a MULTYRAMA fitting must beconnected to an iron pipe or union, the connection should be madeusing MULTYRAMA fittings with male thread.

CONTACT WITHSHARP-EDGEDBODIES

CURVATURE

CALIBRATION

CUTTING

FITTINGS WITHFEMALE THREAD

Chap. 9

28

It must be remembered that if the fluid transported is water, at thetemperature indicated above the following change in state takesplace:

T ≤ 0°C

liquid (water) solid (ice)

and is accompanied by an increase in volume which leads to greaterstress on the pipe. This stress may reach levels incompatible with the properties of thematerial, so freezing should be prevented by adopting one of theseprecautions:

1) for heating systems:

- empty when not in use;

- add anti-freeze agents (as in air-conditioning systems);

- insulate as appropriate.

2) for water supply systems:

In this case, health requirements mean that the freezing point cannotbe lowered by adding additives, and so the main precautions are toincrease the level of pipeline insulation, and to create recycling loopsfor the most exposed sections.

N.B. It is a common mistake to think that insulating pipes will eliminate allrisk of freezing over time.

Remember that insulation is a barrier, designed essentially todelay the onset of freezing, and can never make it impossible.

SYSTEMS ATAMBIENT TEMPERATURE ≤ 0°C

Chap. 9

29

The purpose of system testing is always to identify any points whereleakages occur, regardless of their causes.

Therefore, for the installater the testing procedure will consist of thefollowing operations:

• visual check on pipes

• visual check on joints

• tightness test

This last phase is carried out as follows: before the system is totally covered with mortar or concrete, it mustbe filled with water at ambient temperature, taking care to vent anyair bubbles. After filling and after sealing the system, it is pressurizedfor 24 h with the following pressure value:

TESTING PRESSURE = 10 bar

After the indicated time and, with the system under pressure, a sightinspection will ensure the operator there are no leaks.If any leaks are found, after remedying the situation, the system willhave to be tested again.

Correct use of MULTYRAMA and its unions, together with carefultesting, will prevent any problems including in those sections forconveying hot water.

N.B. In case of any leaks, pressing the joint again will not solve theproblem. The only thing to do is replace the union. After performingthe test, test pressure is released from the system. Occasionally it isa good idea to fully empty the system, especially if this is located inareas where temperatures are near or below 0°C. This will preventany unexpected breakages due to the formation of ice on systemspresumed to be already tested and consequently without faults.

Introduction

PROCEDURE

Chap. 10

Esempio:

Example:

To use the monogram, at least two quantities will have to be established, one of which is the sizeof the pipe and the second generally the flow rate or speed.

Pipe: Ø 32 x 3

int. Ø = 26 mm (point A)speed 1 m/s (point B)

By joining points A and B with a straight line, points C and D are found which indicate a flow resi-stance J = 0.05 m/m and a flow rate Q = 0.54 l/s

FLOW RESISTANCE DIAGRAM

31

B

C

A

D

WATER AT 20 ° C

SPEED(m/s)

FLOW RESISTANCE(m/m)

INTERNAL DIAMETER(mm)

FLOW RATE(l/s)

32

WATER AT 60 ° C

SPEED(m/s)

FLOW RESISTANCE(m/m)

INTERNAL DIAMETER(mm)

FLOW RATE(l/s)

Prandelli s.r.l. via Rango,58 - 25065 Lumezzane (BS) Italia tel. +39 0308 920 992 Fax +39 0308 921 739www.prandelli.com e-mail: prandelli@prandelli.com