jerms-d-3205 manufacture of atmospheric tanks

7/25/2019 JERMS-D-3205 Manufacture of Atmospheric Tanks

1/39

JERMS-D-3205

Manufacture of

Atmospheric Tanks

Revision

2

Responsibility

JER Engineering Division

4 November

2008

Jubail Export Refinery

Material Specifications


2/39



JERMS-D-3205

Rev-2Manufacture of Atmospheric Tanks 4 November 2008

This document is the property of Jubail Export Refinery and no parts of this document shall be reproduced by

any means without prior approval by the Company.

Page 2 of 39

Revision Tracking

Revision Revision Date Scope of Revision

2 4 November 2008Revised to update paragraphs: 3.1, 13.1.1, 8.3.2, 14.1.Adding references: JERES-H-001, JERES-H-002 & JERES-H-005

1A 2 October 2008 Revised to update par. 3.1, 8.6.8.2; Par. 10.1.2 and 13.1.1 and 14.3

0 29 April 2008 Issued for bid package.

03 14 April 2008 For adjusting formatting

02 31 March 2008 Issued for bid package. Only for Review

01 03 August 2007 The first official JERMS-D-3205 is issued

0008 February2007

First draft issued is based on Saudi Aramco 32-SAMSS-005Manufacture of Atmospheric Tanks issue date 31 December, 2003.

Document was modified to incorporate amendments and modifications.


3/39



JERMS-D-3205




Page 3 of 39

Table of Contents

Section Contents Page

1 Scope 5

2 Conflicts, Deviations and Clarifications 5

3 References 5

4 Definitions 7

5 Introduction Note 8

6 (1) Scope 8

7 Materials 9

8 Design 10

9 Fabrication 17

10 Erection 17

11 Methods of Inspecting Joints 22

12 Welding Procedure and Welder Qualifications 23

13 Marking 23

14 Coatings and Painting 24

15 Documentation 24

16 Disinfection 24

Appendixes


4/39



JERMS-D-3205




Page 4 of 39

B Recommendations for Design and Construction of Foundationfor Aboveground oil Storage Tanks

26

C External Floating Roofs 27

G Structurally Supported Aluminum Dome Roofs 31

H Internal Floating Roofs 33


5/39



JERMS-D-3205




Page 5 of 39

1 Scope

This standard covers the minimum mandatory requirements that shall be used as the

basis for developing detailed design and construction of foundations for storagetanks.

2 Conflicts, Deviations and Clarifications

2.1 Any conflicts between this standard and other applicable Company EngineeringStandards (JERES), Material Specifications (JERMS), Standard Drawings (JERSD),

Engineering Procedures (JEREP), Company Forms or Industry standards,

specifications, Codes and forms shall be brought to the attention of CompanyRepresentative by the Contractor for resolution.

Until the resolution is officially made by the Company Representative, the most

stringent requirement shall govern.

2.2 Where a licensor specification is more stringent than those of this standard, the

Licensors specific requirement shall apply.

2.3 Where applicable Codes or Standards are not called by this standard or its

requirements are not clear, it shall be brought to attention of CompanyRepresentative by Contractor for resolution.

2.4 Direct all requests for deviations or clarifications in writing to the Company or itsRepresentative who shall follow internal Company procedure and provide final

resolution.

3 References

The selection of material and equipment, and the design, construction, maintenance,

and repair of equipment and facilities covered by this standard shall comply with thelatest editionof the references listed below as of the CUT-OFF DATE as specified

in the Contract unless otherwise noted.

3.1 Company References

Company Engineering Standards

JERES-A-007 Hydrostatic Testing Fluids and Lay-Up Procedures

JERES-A-112 Meteorological and Seismic Design Data


6/39



JERMS-D-3205




Page 6 of 39

JERES-A-206 Positive Material IdentificationJERES-B-017 Fire Water System Design

JERES-B-018 Air Foam Systems for Storage Tanks

JERES-H-001 Coating Selection & Application Requirements for Industrial

Plants & Equipment.

JERES-H-002 External Coatings for Buried Steel Piping and Pipelines

JERES-H-005 Internal Coating for Vessels, Tanks and Equipment

JERES-J-300 Level

JERES-J-600 Pressure Relief DevicesJERES-W-017 Welding Requirements for API Tanks

Company Materials Specifications

JERMS-G-3217 Side-Entry Mixers

JERMS-H-9107 Qualification Requirements and Application of Composite

Fluropolymer/Ceramic Coatings to Fasteners

JERMS-J-4319 Radar Tank Gauging Equipment

Company Standard Drawings

JERSD-D-0001 Manholes and Vents for Tanks

JERSD-D-0002 Roof Center Vent for Cone-Roof Tanks

JERSD-D-0003 Radar, Temperature and Manual Gauging Assembly for

Floating Roof Tanks

JERSD-X-0013 Half Shell Bracelet Type Anode for Pipe Sizes 4-60 Inch

JERSD-P-0003 Tank Grounding

JERSD-D-0004 General Assembly of Gauge well for External Floating Roof

Tanks

Company Inspection Requirements

JERITP-D-324900 Tanks: Atmospheric, Steel within the Scope ofJERMS-D-3205

Company Forms and Data Sheets

Form NMR-7918-1 Nonmaterial Requirements for Tanks


7/39



JERMS-D-3205




Page 7 of 39

Form NMR-7918-2 Nonmaterial Requirements for Floating and Internal FloatingRoofs

3.2 Industry Codes and Standards

American Petroleum Institute

API STD 650 Welded Steel Tanks for Oil Storage

API STD 2000 Venting Atmospheric and Low-Pressure Storage Tanks

API RP 2003 Protection Against Ignitions Arising Out of Static, lightning,

and Stray Currents

American Society of Mechanical Engineers (Boiler and Pressure Vessel Code)

ASME B16.11 Forged Fittings, Socket-Welding and Threaded

ASME SEC V Nondestructive Examination

National Fire Protection Association

NFPA 68 Guide for Venting of Deflagration

NFPA 255 Standard Method of Test of Surface Burning Characteristics of

Building Materials

American Water Works Association

AWWA C652 Disinfection of Water Storage Facilities

4 Definitions

4.1 Definitions presented in this Standard and other JER documents have precedence

over other definitions. Conflicts between various definitions shall be brought to theattention of Company Representative by the Contractor for resolution.

Company: Jubail Export Refinery.

Company Representative: A designated person from the Company or an assignedthird party representative.

Company Inspector:A designated person or an agency responsible for conducting

inspection activities on behalf of the Company.

4.2 List of Definitions


8/39



JERMS-D-3205




Page 8 of 39

Design Engineer: The Engineering Company responsible for specifying the designrequirements on the Storage Tank Data Sheet.

Design Metal Temperature: The lowest of the following temperature values:

1) The lowest one-day mean atmospheric temperature (LODMAT) per JERES-A-

112, or

2) The minimum operating temperature, or

3) The hydrostatic test temperature

Tank Manufacturer: The Company responsible for the design and fabrication of

tanks.

5 Introduction Note

The API STD 650, Third Edition, September 2003, is part of this specification. The

text in each paragraph below is an addition, deletion or exception to API STD 650 as

noted in parenthesis. Paragraph numbers not appearing in API STD 650 are newlyadded paragraphs inserted in numerical order. For these new paragraphs there is no

addition, deletion or exception wordings in parenthesis.

The API STD paragraph numbers are indicated in parenthesis.

Only the paragraphs of the API STD 650 that have been modified (by addition,

deletion or exception) by this standard are mentioned. The other API STD 650

paragraphs that are not mentioned in this standard remain applicable.

6 (1) Scope

6.1 (1.1) General

6.1.2 (1.1.6) Appendix B and all other pertinent requirements of this specification shall be

used as the basis for developing detailed design and construction of foundations forstorage tanks.

6.1.3 (1.1.7) Additional requirements for external floating roofs are contained in

Appendix C of this specification.

6.1.4 (1.1.11) Additional requirements for optional self-supporting aluminum dome

roofs are contained in Appendix G of this specification.


9/39



JERMS-D-3205




Page 9 of 39

6.1.5 (1.1.12) Additional requirements for internal floating roofs are contained inAppendix H of this specification.

6.1.6 (1.1.23) This specification shall be attached to and form an integral part of a

purchase order.

6.2 (1.3 )Compliance

6.2.1 (1.3.1) Any conflicts between this standard and other applicable Company

Engineering Standards (JERESs), Materials Specifications (JERMSs), StandardDrawings (JERSDs), or industry standards, codes, and forms shall be resolved in

writing by the Company Engineering Manager.

Until the resolution is officially made by the Company Engineering Manager, themost stringent requirement shall govern.

Direct all requests to deviate from this standard in writing to the Company

Representative, who shall follow internal Company procedure.

6.2.2 (1.3.2) Direct all requests to deviate from this specification in writing to the

Company Representative.

6.2.3 (1.4)Referenced Publications

Materials or equipment supplied to this specification shall comply with the latest

edition of the references listed below and those referenced in API 650, unless

otherwise noted.

7 (2) Materials

7.1 (2.1) General

7.1.1 (2.1.1) The Tank Manufacturer shall submit a complete material specification

with the proposal.

The Tank Manufacturer may propose the use of alternative materials to those that arelisted in API STD 650. The alternative materials shall comply with all the other

requirements of API STD 650 and this specification. The chemical compositions

and mechanical properties of non-ASTM materials shall be submitted to theCompany Representative for approval.


10/39



JERMS-D-3205




Page 10 of 39

Materials proposed by the Tank Manufacturer that are equivalent to those specifiedin API STD 650 shall be approved by the Company Representative.

7.1.2 (2.1.2) Exception

All materials shall be clearly identified and provided with mill test certificates.

Materials shall be alloy-verified by the Tank Manufacturer in accordance with

JERES-A-206.

7.1.3 (2.2) Plates

7.1.4 (2.2.1) General

7.1.5 (2.2.1.5) Annular plate material shall be of the same material group per API STD650 as the lowest shell course.

7.1.6 (2.2.1.6) Rimmed and capped steels shall not be used for shell, bottom and roof

plates.

7.1.7 (2.2.9.3) Exception

The design metal temperature as defined in paragraph 1.5 of this specification shall

be used as the basis for impact test exemption of Figure 3.1 of API STD 650.

7.2 (2.7) Bolting

Flange bolting material shall conform to A193 Grade B7 bolts with A194 Grade 2H

nuts. All bolting shall be coated with a fluoropolymer/ceramic coating in accordance

with JERMS-H-9107.

7.3 (2.9) Gaskets

Gasket materials shall be non-asbestos.

8 (3) Design

8.1 (3.1) Joints

8.1.1 (3.1.3) Restrictions on Joints

8.1.2 (3.1.3.5) Lap-welded joints shall be lapped at least five times the nominal

thickness of the thinner plate joined; however, with double-welded lap joints, the lap


11/39



JERMS-D-3205




Page 11 of 39

need not exceed 50 mm (2 in.), and with single-welded lap joints, the lap shall not beless than 25 mm (1 in.).

8.1.3 (3.1.5) Typical Joints

8.1.4 (3.1.5.3a) Exception

Top angles shall be attached to the shell by butt welds with complete penetration and

complete fusion.

8.2 (3.2) Design Considerations

8.2.1 (3.2.6) Information provided by the Design Engineer on the API STD 650Storage Tank Data Sheet and a completed Company Form 2696-ENG shall be usedfor the tank design in accordance with API STD 650 and this specification.

8.2.2 (3.2.7) Nozzle Loads

8.2.3 (3.2.7.1) Associated piping systems loads shall be specified on the tank data sheet.

8.2.4 (3.2.7.2) Tank Manufacturer shall ensure that stresses at nozzle-to-tank

connections, due to piping loads specified on the tank data sheet, are within the

allowable limits.

8.3 (3.3) Special Considerations

8.3.1 (3.3.4) Weld Hardness

Weld hardness testing requirements and acceptance criteria shall be in accordance

with JERES-W-017.

8.3.2 (3.3.5) A foundation drip ring shall be provided in order to prevent the ingress

of rainwater or condensation between the tank bottom and foundation. The ring shallmeet the following requirements.

1) Material shall be carbon steel, 3.2 mm (1/8 inch) thick.

2) Continuously seal welded to the edge of the tank bottom or annular plate. All

radial joints between the drip ring sections shall also be seal welded.

3) Extend at least 75 mm (3 inch) beyond the outer periphery of the concrete ring

wall.

4) Turn down at its outer diameter at a 45-degree angle.


12/39



JERMS-D-3205




Page 12 of 39

5) The top of the drip ring and a 75 mm (3 inch) height of the tank shell shall bepainted with a 250-300 microns (10-12 mils) thick epoxy coating in accordance

with JERES-H-001.

8.3.3 (3.3.6) Under-tank leak detection and sub-grade protection

8.3.4 (3.3.6.1) Tanks in services other than water shall be provided with under tank leakdetection and sub-grade protection according to API STD 650, Appendix I.

Acceptable construction details are Figures I-1, I-2, I-3, I-6, I-7, I-8, I-9 and I-10.

8.3.5 (3.3.6.2) Flexible membrane leak-barrier (liner) of minimum 1000 microns (40

mils) thickness compatible with the stored product shall be specified under the tankbottom. The liner shall be placed in accordance with JERSD-X-0013, extending to

the internal top edge of the ring foundation.

8.3.6 (3.3.6.3) Joints in the liner shall satisfy the leak tightness, permeability and

chemical resistance requirements for the liner material.

8.3.7 (3.3.6.4) Alternative under-tank leak detection and sub-grade protection systems

shall not be permitted without the prior approval of the Company Representative.

8.3.8 (3.3.7) Reinforcing pads and all other external attachment pads shall haverounded corners of minimum 50 mm (2 inch) radius. Pads that cover shell seams

shall be provided with a 6 mm telltale hole.

8.4 (3.4) Bottom Plates

8.4.1 (3.4.4) Tank bottom shall be sloped in accordance with the specification

provided on the Storage Tank Data Sheet.

8.4.2 (3.4.5) Bearing plates shall be provided under all fixed roof support columns.

The bearing plates shall be twice the diameter of the column section with a minimum

356 mm diameter (14 inch), 12.7 mm (1/2 inch) thick, and shall be attached to thebottom by 4.8 mm (3/16 inch) continuous fillet welds.

8.5 (3.6) Shell Design

8.5.1 (3.6.5) Design methods other than the one-foot method and the variable-design-point method provided in API STD 650 shall be approved by the Company

Representative.

8.5.2 (3.7) Shell Openings


13/39



JERMS-D-3205




Page 13 of 39

8.5.3 (3.7.1) General

8.5.3 (3.7.1.10) Number, size, type, and orientation of nozzles and manways shall be in

accordance with JERSD-D-0001and as specified on the Storage Tank Data Sheet.

8.5.4 (3.7.6) Shell Nozzles and Flanges

8.5.4 (3.7.6.4) All shell nozzles shall be the API Low Type, unless otherwise specified.

8.6 (3.8) Shell Attachments and Tank Appurtenances

8.6.1 (3.8.2) Bottom Connections

When specified, bottom connections shall be designed in accordance with API STD650, Appendix O.

Connections shall be fabricated from elbows; miter joints are prohibited.

Vortex breakers shall be provided for bottom connections.

8.6.2 (3.8.5) Roof Nozzles

8.6.3 (3.8.5.3) All open vents shall be protected by bird screens, except those in asphalt

service.

8.6.7 (3.8.9) Threaded Connections

Threaded and socket welded connections shall be in accordance with ASME B16.11.

8.6.8 (3.8.10) Platforms, Walkways, and Stairways

8.6.8.1 (3.8.10.1) Type and location of stairway shall be as specified on the Storage TankData Sheet and Company Form 2696-ENG.

8.6.8.2 (3.8.10.2) Gauger's platform in accordance with JERSD-D-0006 shall be provided

for external floating roof tanks.

8.6.8.3 (3.8.10.3) Stairs and platforms shall be fabricated of open grating. Checker-plate

grating is not permitted.

8.6.8.4 (3.8.10.4) Walkways shall be fabricated of diamond-pattern (checker-plate) grating

with anti-skid paint.


14/39



JERMS-D-3205




Page 14 of 39

8.6.8.5 (3.8.10.5) Stairways on insulated tanks shall be provided with stringers on bothsides.

8.6.9 (3.8.11) Floating Suction Lines

8.6.9.1 (3.8.11.1) Floating suction lines shall be provided, when specified on the Storage

Tank Data Sheet.

8.6.9.2 (3.8.11.2) Floating suction lines using rigid pipe shall be designed to prevent them

from being raised past the vertical axis.

8.6.9.3 (3.8.11.3) Floating suction lines using articulated pipe shall be designed so that the

tip of the suction line is always on the axial centerline of the tank throughout its totaltravel.

8.6.10 (3.8.12) Inlet Diffusers

8.6.10.1 (3.8.12.1) An inlet diffuser shall be provided for tanks with internal floating roofs.

The inlet diffuser shall be sized based on the maximum pumping in rate and themaximum permissible exit velocity through the slots in the diffuser.

8.6.10.2 (3.8.12.2) The diffuser shall be slotted. The slots shall be located at 60 degrees (2

o'clock and 10 o'clock positions) from the vertical centerline of the diffuser.

8.6.10.3 (3.8.12.3) Number and dimensions of slots shall be calculated so that the exit

velocity does not exceed 1 m/sec (3.28 ft/sec) at the maximum inlet flow until there

is a minimum of 1m of liquid cover over the inlet.

8.6.11 (3.8.13) Mixers

8.6.11.1 (3.8.13.1) Number and type of mixers shall be as specified on the Storage Tank

Data Sheet.

8.6.11.2 (3.8.13.2) Side-entry propeller mixers shall be designed, inspected, and tested inaccordance with JERMS-G-3217.

8.6.11.3 (3.8.13.3) Nozzles for side-entry mixers shall be designed in accordance with APISTD 650 for manways. Supports for the mixer may be needed to maintain stresses at

the nozzle-to-shell junction within the allowable limits.

8.6.11.4 (3.8.13.4) Jet-nozzle mixers shall not be used in tanks with internal floating roofs

on floats.


15/39



JERMS-D-3205




Page 15 of 39

8.6.12 (3.8.14) Foam and Water Systems

Fire or cooling water and foam systems shall be provided in accordance with JERES-

B-017and JERES-B-018, respectively, when specified on the Storage Tank Data

Sheet.

8.6.13 (3.8.15) Gauging

8.6.13.1 (3.8.15.1) External-floating roofs shall be provided with a radar gage assembly in

accordance with JERSD-D-0003and JERES-J-300.

8.6.13.2 (3.8.15.2) External floating roof tanks shall be provided with a radar liquid level

gauge in accordance with JERMS-J-4319, located adjacent to the gauger's platform.The top of the gauge piping shall be located from 150 mm (6 inch) to 300 mm (12inch) above the platform handrail and approximately 150 mm (6 inch) horizontally

from the gauger's platform for easy maintenance access.

8.6.13.3 (3.8.15.3) Fixed-roof tanks shall be provided with a radar gauge assembly.

8.6.14 (3.8.16) Grounding

8.6.14.1 (3.8.16.1) Tanks in hydrocarbon services shall be provided with grounding lugs in

accordance with JERSD-P-0003at a minimum of four points spaced equidistantly

around the base of the tank.

8.6.14.2 (3.8.16.2) The design of bonding shunts between the tank shell and the roof shall

be in accordance with JERSD-P-0003and API RP 2003 requirements.

8.7 (3.9) Top and Intermediate Wind Girders

8.7.1 (3.9.4) Stiffening Rings as Walkways

Top wind girders, when specified as walkways, shall be located 1067 mm (42 inch)

from the top of the tank.

8.7.2 (3.9.7) Intermediate Wind Girders

8.7.2.1 (3.9.7.1) The minimum required thickness for the design condition, excluding

corrosion allowance, shall be used to calculate the maximum height of unstiffenedshell.

8.8 (3.10) Roofs


16/39



JERMS-D-3205




Page 16 of 39

8.8.1 (3.10.2) General

8.8.1.1 (3.10.2.1) Type of roof shall be as specified on the Storage Tank Data Sheet.

8.8.1.2 (3.10.2.9) When an internal coating is specified for a fixed roof, a self-supported

roof shall be used, and the roof lap joints shall be continuously welded on both sides.

For internal tank walls, surface preparation, painting, and coating specifications shall

be selected in accordance with JERES-H-005.

8.8.2 (3.10.4) Supported Cone Roofs

8.8.2.1 (3.10.4.6) Exception

Only welded joints are permitted for all structural attachments in the roof supporting

system other than the following joints:

a) Rafter clips for the outer row to the tank shell.

b) Column-base clip guides to the tank bottom.

8.8.3 (3.10.5) Self-Supporting Cone Roofs

Only welded joints are permitted for all structural attachments in the roof supportingsystem.

8.8.4 (3.10.6) Self-Supporting Dome and Umbrella Roofs

Only welded joints are permitted for all structural attachments roofs' supportingsystems in self-supporting roofs, except for self-supporting aluminum dome roofs.

8.8.5 (3.10.8) Tank Venting

8.8.5.1 (3.10.8.1) Exception

Fixed roof tanks with internal floating roofs shall be treated as fixed roof tanks when

determining their venting requirements.

Commentary Note:

When circulation vents are not installed in fixed roof tanks with an internal floating roof,

individual designated venting devices/arrangement shall be provided for the fixed roof and

the internal floating roof according to venting requirements of API STD 2000 and this

specification.


17/39



JERMS-D-3205




Page 17 of 39

8.8.5.2 (3.10.8.3) Exception

Emergency venting capacity per API STD 2000 and explosion hatch per NFPA 68

shall be provided for API STD 650 fixed roof tanks. A frangible shell-to-roof joint

may be considered as an alternative to additional venting devices that are normally

provided to relieve excess pressure during emergency conditions for tanks of

diameters equal to or larger than 50 feet. Frangible shell-to-roof joint shall conform

to the requirements of API STD 650.

8.8.5.3 (3.10.8.4) Venting requirements shall be specified in accordance with API STD

2000, JERES-J-600, JERSD-D-0001and JERSD-D-0002and the requirements ofthis specification.

9 (4) Fabrication

9.1 (4.1) General

9.1.1 (4.1.1) Workmanship

9.1.1.1 (4.1.1.3) All flange bolt holes shall straddle the axial centerline of the tank.

9.1.2 (4.1.4) Marking

9.1.2.1 (4.1.4.1) Marking shall be done with water soluble materials containing nosubstances that would attack or harmfully affect the tank at both ambient and

operating temperature.

9.1.2.2 (4.1.4.2) Marking materials shall be free of lead, sulfur, zinc, cadmium, mercury,

chlorine or any other halogens.

9.1.3 (4.1.5) Shipping

All flange faces and other machined surfaces shall be greased and properly protected

for shipping.

9.2 (4.2 )Shop Inspection

9.2.1 (4.2.3) Company Inspector shall have the right to inspect the fabrication at anystate and to reject material or workmanship, which does not conform to the specified

requirements.

10 (5) Erection


18/39



JERMS-D-3205




Page 18 of 39

10.1 (5.1) General

10.1.1 (5.1.1) The Tank Manufacturer shall check to ensure that the dimensional

tolerances of the tank foundation are satisfactory prior to start of erection.

10.1.2 (5.1.6) The bottom side of the bottom plates shall be cleaned of all foreign

matter and grit-blast cleaned prior to being coated and placed in position for welding.The topside surface of bottom plates, regardless whether coating is required or not,

shall also be grit-blast cleaned prior to welding. Surface preparation shall be

according Mfrs datasheet recommendation.

10.2 (5.2 )Details of Welding

10.2.1 (5.2.1) General

10.2.1.1 (5.2.1.11) Documentation that details the welding sequences for the tank shall beprovided to Company prior to the start of field erection.

10.2.1.2 (5.2.1.12) All structural attachment welds to the tank shell, bottom, roof, andappurtenances shall be continuously seal welded.

10.2.1.3 (5.2.1.13) All welds shall be free from coarse ripples, undercuts, grooves, overlaps,

abrupt ridges and valleys to avoid stress concentration points and interference with

interpretation of NDT results.

10.2.2 (5.2.2) Bottoms

10.2.2.1 (5.2.2.4) Weld crowns of the bottom annular plate joints shall be ground flush at

the contact areas with the first shell course.

10.2.3 (5.2.4) Shell-to-Bottom Welds

Exceptions

a) Perform oil-penetrate leak test on the entire length of the first weld pass by applying

high flash point penetrant oil such as light diesel oil for a minimum 4 hours(preferably overnight).

b) Perform oil-penetrate leak test on the entire length of the first completed weld, before

welding the second fillet weld, by applying high flash point penetrant oil such as light

diesel oil for a minimum 4 hours (preferably overnight). Alternatively, apply a vacuum

test at 35 kPa gauge (5 psig), using a vacuum box fit to the shell-to-bottom junction.


19/39



JERMS-D-3205




Page 19 of 39

c) The inside fillet welds of the shell-to-bottom joint in a cylindrical flat-bottom tankshall be examined by either the dye-penetrant or wet-fluorescent magnetic particle

method before hydrotest.

10.2.4 (5.2.5) Roofs

10.2.4.1 (5.2.5.1) Internal floating roofs shall be installed in accordance with the

instructions provided by the internal floating roof manufacturer.

10.2.4.2 (5.2.5.2) Prior to the installation of fixed roof plates, roof 's column supports shall

be inspected for plumbness. Roof support columns with out-of-plumbness exceeding1/200 of the total tank shell height shall be realigned.

10.2.4.3 (5.2.5.3) All internal clips, lugs, brackets etc. that are used temporarily for

construction purposes shall be removed from the roof supporting columns and shell

plates and ground flush and smooth prior to roof installation.

10.3 (5.3 )Inspection, Testing, and Repairs

10.3.1 (5.3.1) General

10.3.1.1 (5.3.1.1) Inspection shall be in accordance with Company Inspection Requirement

JERITP-324900, JERES-W-017and the following additional requirements.

10.3.1.2 (5.3.1.5) All required Nondestructive Examination shall be performed in

accordance with inspection procedures that are in complete compliance with ASMESEC V and this specification. This written procedure shall address each inspection

method and technique used including acceptance criteria. When required by the

purchase order the procedure(s) shall be submitted to Company Inspection

Department for approval.

10.3.1.3 (5.3.1.6) All Nondestructive Examination, including Magnetic Particle and LiquidPenetrant examinations, shall be performed by personnel certified or equivalent

National Certification Programs that has been approved by the Company Inspector.

Personnel responsible for interpretation of Nondestructive Examination results shall

be certified to a minimum of Level II.

10.3.1.4 (5.3.1.7) Prior to final inspection and pressure testing, the inside and outside ofthe tank shall be thoroughly cleaned of all slag, scale, dirt, grit, weld spatter, paint,

oil, etc.


20/39



JERMS-D-3205




Page 20 of 39

10.3.1.5 (5.3.1.8) Company Inspector may reject the use of any materials, equipment, ortools that do not conform to the specification requirements, jeopardize the safety of

personnel, or impose hazard or damage to Company property.

10.3.1.6 (5.3.1.9) Testing shall be in accordance with Company Inspection RequirementsForm 175-324900 and the following additional requirements.

10.3.2 (5.3.3) Inspection of Tank Bottom Welds

Exception

Only vacuum box test method is permitted.

10.3.3 (5.3.5) Testing of the Shell

10.3.3.1 (5.3.5.1) Tanks shall be hydrostatically tested by filling it with water of quality inaccordance with JERES-A-007as follows:

1) to the maximum design liquid level, H specified in API STD 650,

2) for a fixed roof tank , to 50 mm (2 in.) above the weld connecting the roof plate

or compression bar to the top angle or shell; or

3) to a level lower than that specified in items (a) or (b) when restricted by

overflow, an internal floating roof, or other freeboard.

10.3.3.2 (5.3.5.2) Hydrostatic testing duration shall be minimum 24 hours. The water-filling rate shall not exceed the rate shown in the following table:

Water Filling Rate Table

Bottom Course Thickness Tank Portion Filling Rate

Less than 22 mmTop course 300 mm/hour

Below top course 450 mm/hour

22 mm and more

Top third of tank 225 mm/hour

Middle third of tank 300 mm/hour

Bottom third of tank 450 mm/hour

10.3.3.3 (5.3.5.3) Testing of the shell by a method other than hydrotesting such as painting

with highly penetrating oil, applying vacuum or a combination of both methods isnot permitted.


21/39



JERMS-D-3205




Page 21 of 39

10.3.3.4 (5.3.5.4) Floating roof seals, either primary or secondary, shall be completelycontained within the shell when the test water level reaches the test liquid level.

10.3.3.5 (5.3.5.5) The Tank Manufacturer shall furnish all test materials and facilities,

including blinds, bolting, and gaskets.

10.3.3.6 (5.3.5.6) The tank shall be completely drained and thoroughly dried immediatelyafter completion of the hydrostatic test. If sea water or raw water is used for

hydrostatic testing of tanks in other than these services, the tank shall be thoroughly

washed with fresh water immediately after draining.

10.3.3.7 (5.3.5.7) The Tank Manufacturer's plan for disposal of hydrotest water shall beevaluated by the engineering contractor.

10.3.4 (5.3.6) Testing of the Roof

10.3.4.1 (5.3.6.1) Exception

All roof weld joints of a tank designed to be gas tight, such as a tank with peripheral

circulation vents or a tank with free or open vents, shall be vacuum box tested.

Applying internal pressure for the detection of leaks is not permitted. External

floating roof testing shall be in accordance with Appendix C of this specification.

Internal floating roof testing shall be in accordance with Appendix H of this

specification.

10.3.5 (5.3.8) Magnetic Particle or Liquid Penetrant Examination

The dye penetrant or magnetic particle method before the hydrostatic test.

10.4 (5.4 )Repairs to Welds

10.4.1 (5.4.5) Repairs to welds shall be in accordance with JERES-W-017.

10.5 (5.6 )Tank Settlement Measurements

10.5.1 (5.6.1) The base elevation shall be established and recorded at equidistantlocations around the tank circumference in multiples of four, but not to exceed 10 m(32.8 foot) between each reference point and no less than eight (8) locations. The

measurement points shall be at well marked locations on the bottom projection

outside the tank or on clips welded to the shell. Elevation readings shall be taken asfollows:

1) Before hydrostatic testing has started.


22/39



JERMS-D-3205




Page 22 of 39

2) At the filled point.3) At the filled point.

4) After 24 hours from filling the tank at the maximum water fill height.

5) After the tank has been emptied of test water.

10.5.2 (5.6.2) Any differential settlement greater than 1.5 mm (60 mils) per meter of

circumference, or a uniform settlement in excess of 50 mm (2 inch), shall bereviewed by the Company Representative. Filling shall be stopped until clearance to

continue has been received from the Company Representative.

10.5.3 (5.6.3) For tanks 15.24 m (50 foot) diameter and larger, internal bottomelevation measurements shall be made before and after the hydrostatic test. These

measurements shall be made at 3 m intervals along diametric lines across the bottom.

The diametric lines shall be spaced approximately 10 m (32.8 foot) apart at the tank

shell.

11 (6) Methods of Inspecting Joints

11.1 (6.1) Radiographic Method

11.1.1 (6.1.1) Application

Exception

Radiographic inspection is required for the weld joining the top angle to the shell.

11.1.2 (6.1.2) Number and Location of Radiographs

11.1.2.1 (6.1.2.4) Exception

This requirement is permitted only if a group of tanks are erected by the same tank

manufacturer.

11.1.3 (6.1.5) Radiographic Standards

Tungsten inclusions in gas tungsten arc welds shall be evaluated as individualrounded indications. Clustered or aligned tungsten inclusions shall be removed and

repaired.

11.1.4 (6.1.6) Determination of Limits of Defective Welding


23/39



JERMS-D-3205




Page 23 of 39

The additional spots to be radiographed shall be specified by the Company Inspectorin accordance with JERES-W-017.

11.2 (6.2 )Magnetic Particle Examination

11.2.1 (6.2.5) Magnetic Particle Examination shall be according to JERES-W-017.

11.3 (6.5) Visual Inspection

Welds shall be visually inspected for any defects prior to performing nondestructive

examination (radiography, magnetic particle, liquid penetrant, ultrasonic). Visual

inspection shall not replace any required nondestructive examination.

11.4 (6.6) Vacuum Testing

11.4.1 (6.6.3) Exception

A partial vacuum of 70 kPa gauge (10 psig) shall be used for the test.

11.4.2 (6.6.11) Delete this paragraph.

12 (7) Welding Procedure and Welder Qualifications

12.1 (7.2) Qualification of Welding Procedures

12.1.1 (7.2.1) General Requirements

12.1.1.1 (7.2.1.1) All welding procedures and procedure qualifications shall be in

accordance with JERES-W-017and be submitted for review by Company

13 (8) Marking

13.1 (8.1) Nameplates

13.1.1 (8.1.5) All tanks with internal coatings shall have the Approved Protective

Coating Systems specification number marked on the nameplate. For internal tankwalls, surface preparation, painting, and coating specifications shall be selected in

accordance with JERES-H-005.

For buried external section of tank walls, surface preparation, painting, and coating

specifications shall be selected in accordance with JERES-H-002.


24/39



JERMS-D-3205




Page 24 of 39

13.2 (8.4) Tank number and content shall be painted in both Arabic and English at90 degree intervals around the tank.

13.3 (8.5) Marking shall be done with water soluble materials containing no

substances that would attack or harmfully affect the tank at both ambient andoperating temperature.

13.4 (8.6) Marking materials shall be free of lead, sulfur, zinc, cadmium, mercury,

chlorine, or any other halogens

14 (9) Coatings and Painting

14.1 (9.1) Type of coating and painting systems to be applied shall be as specified

on the Storage Tank data Sheet.

For external tank walls, surface preparation, painting, and coating specifications shall


For internal tank walls, surface preparation, painting, and coating specifications shall


For buried external section of tank walls, surface preparation, painting, and coatingspecifications shall be selected in accordance with JERES-H-002.

14.2 (9.2) Surfaces to be coated shall be cleaned and prepared prior to its coating in

accordance with the applicable coating and painting systems.

14.3 (9.3) Tank placed directly on soil sub-grade shall be coated with Coal tar

Epoxy paint, 600thick or Epoxy coating for Atmospheric service, 450thick, asapplicable, on its soil side leaving minimum 2.5 cm (1 inch) wide strip of uncoated

steel along the underside of the floor plate, centered on, and directly below the weldseam. This will typically require masking a strip along the underside of each end

(edge) of each bottom plate approximately 5 cm (2 inch) wide. Coal tar Epoxy paint

shall be specified for tank with maximum operation temperature of 70C (158F),

while Epoxy coating for Atmospheric service shall be specified for higher operationtemperatures up to 150C.

14.4 (9.4) In tanks where internal coating is not required, top side of the bottom and

the bottom portion of the shell, starting from the tank bottom up to minimum onefoot above water line, shall be coated according to the applicable coating

specifications.


25/39



JERMS-D-3205




Page 25 of 39

14.5 (9.5) Gasket contact surfaces shall not be coated or painted.

14.6 (9.6) The tank number and content shall be painted in both Arabic and English

at 90 degree intervals around the tank.

15 (10 )Documentation

The Tank Manufacturer and internal floating roof manufacturer shall prepare

drawings, calculations, and data in accordance with Form NMR-7918-1 and FormNMR-7918-2, Non-Material Requirements, as applicable.

Drawings and calculations, which are approved by the Design Engineer, shall notrelieve the Manufacturer of the responsibility to comply with the Code and this

specification.

16 (11) Disinfection

16.1 (11.1) All potable water storage tanks shall be disinfected in accordance with

AWWA C652.

16.1.1 (11.2) The chlorine and bacteriological tests shall be approved by the CompanyRepresentative.


26/39



JERMS-D-3205




Page 26 of 39

Appendix B Recommendations for Design and Construction of Foundations forAboveground Oil Storage Tanks

B.2 Subsurface Investigation and Construction

B.2.6 Top fill layer 10-15 cm (4-6 inch) shall be a mixture of sweet sand and 3% cement(33:1 ratio, i.e., 3% cement). The material specifications and mixing requirements

shall be as follows:

1) The maximum permissible soil content is 0.1%. Sand shall be dried to a free-

moisture content of not more than 2.0% by weight of dry soil.

2) The dry sand must be screened through 6.4 mm (1/4 inch) mesh (maximum).Care must be taken in using clean mixing and handling equipment to ensure

mixture remains free from foreign matter.

3) The sand shall then be thoroughly mixed with cement in a 33:1 ratio by weight

in a concrete mixer. After laying the mixture shall be rolled a minimum sixtimes by a 3-ton roller. Vibratory plate tampers may be used in lieu of rollers

for areas where a roller cannot reach and/or cover.


27/39



JERMS-D-3205




Page 27 of 39

Appendix C - External Floating Roofs

C.2 MATERIAL

Exceptions

Galvanized parts shall not be used.

Electrical bonding shunt materials shall be Type 304 stainless steel.

C.3 DESIGN

C.3.3 Decks

C.3.3.1 Exception

Roofs shall be of the contact type designed to eliminate the presence of any air-vapor

mixture under the deck.

C.3.4 Pontoon Design

C.3.4.1 Floating roofs shall have sufficient buoyancy to remain afloat based on the lower of

the product specific gravity or 0.7, with the primary drain inoperative for theconditions stated in API STD 650.

C.3.3.5 The deck of single deck pontoon floating roofs shall be in contact with the liquid

during normal operation.

C.3.3.6 Roofs greater than 91 m (300 foot) in diameter shall be of the double-deck type.

C.3.7 Ladders

C.3.7.1 Rolling ladders shall meet the following requirements:

1) The minimum inside width of the ladder shall be 710 mm (28 inch).

2) Wheels shall be provided at the lower end of the ladder and sized to prevent

binding of the ladder at any position and provided with sealed non-lubricating

bearings.

3) Self-leveling treads shall be used for the ladder.


28/39



JERMS-D-3205




Page 28 of 39

C.3.8 Roof Drains

Exception

External floating roofs shall be provided with primary drains of either the flexible pipe

(Coflexip or equal), or the articulated pipe type. A swing type check valve shall be provided

at the inlet of the drain. Siphon type drains are not acceptable for primary roof drains.

Siphon type drains, however, may be provided as a secondary roof drain if specified on the

Storage Tank Data Sheet. Emergency drains for double deck floating roofs shall be of the

open-type design.

C.3.9 Vents

C.3.9.1 As a minimum, two overpressure/vacuum bleeder type vents shall be installed.

Vents shall be sized to handle a total of 125% of the maximum filling/withdrawal

rates that are specified on the Storage Tank Data Sheet.

Commentary Note:

Bleeder vents shall be designed to open and close automatically when the roof is 75mm

above its low support legs position upon emptying and filling the tank, respectively.

C.3.9.2 Vents for protection against overpressure/vacuum, while the roof is floating, shall beprovided as follows:

1) Their overall capacity shall be determined according to API standard 2000

requirements, considering 25% of the filling/emptying rates and 100% of

thermal breathing.

2) Vents shall be evenly distributed and close to the roof periphery enough ventsshall be provided close to the inlet diffuser in services where gas slugs are

expected.

3) Vents shall be designed so as not to allow any carry over of stored liquid onto

the floating roof.

Commentary Notes:

1) Normally, vents are of the open type that does not undergo testing but rather in-situ

inspection. In case relief valves are used, their number shall be such that the total

required venting capacity is always available when a number of valve(s) are removed

for testing.

2) Anticipated operation upset conditions such as an increase in temperature of the input

stream to a tank or chemical injection that will result in vaporization beyond that


29/39



JERMS-D-3205




Page 29 of 39

associated with the true vapor pressure design limit of 90 kPa (13 psia) and gaspurges shall be also considered in determining the required venting capacity.

C.3.10 Supporting Legs

C.3.10.3 Support legs shall be carbon steel pipe, Schedule 80 minimum thickness.

C.3.10.4 Support legs shall be adjustable to two positions. The lower position shall allow the

roof to descend to a position at least 75 mm (3 inch) above internal accessories orroof seal mechanism. The higher position shall provide a 2 m (79 inch) clearance

between the lowest portion of the roof and the tank floor.

C.3.10.5 Bearing plates shall be provided under all support legs so as to distribute the weightof the internal floating roof on the tank bottom plates and to avoid damage to internal

tank coatings. The bearing plates shall be twice the diameter of the support section,12.7 mm (1/2 inch) thick, and shall be attached to the bottom by 4.8 mm (3/16 inch)

continuous fillet welds.

C.3.11 Roof Manholes

Roof manholes shall be provided in accordance with JERSD-D-0001.

C.3.13 Seals

Exceptions

1) If the sealing device employs steel shoes in contact with the shell (pantograph-type),

such shoes shall be made of only Type 304 stainless steel with a minimum nominal

thickness of 1.5 mm (16 gauge).

A low-density polymer type plastic insulation cover shall be provided at the joint

between the middle arm of the pantograph hanger and the connecting rod of the steel

shoe. The insulation cover shall have a press-type locking system and completely

electrically insulate the pantograph hanger with the seal shoe.

2) Any fabric or non-metallic materials used as a seal or seal component shall be

selected based on the design temperature, flammability, permeability, abrasion

resistance, aging, resistance to aromatics, and chemical resistance, and selected fromthe following Table.


30/39



JERMS-D-3205




Page 30 of 39

Seal Materials Table

Fluid Stored Non-Metallic Seal Material

Crude Oil Viton GF (FKM-GF)

Aflas (TFE/P)

Viton (FKM)

Refined Products PFA(Perfluoroalkoxy)

PTFE(Teflon) laminate

PTFE (Teflon) laminate

Gasoline/MTBE Blend KALREZ (Perfluoroelastomer)

CHEMRAZ (Perfluoroelastomer)

KALREZ (Perfluoroelastomer)

MTBE (100%) CHEMRAZ (Perfluoroelastomer)

PTFE (Teflon) laminate

Materials properties verification shall be performed by an independent laboratory.

3) The Tank Manufacturer may offer an alternate design and material at the time

of proposal. However, the alternate design shall comply with the following

requirements:

a) Seals shall be located on the skirt.

b) Materials for non-metallic components of seals shall meet requirements

in paragraph C3.13 (2) of this specification.

4) All fabric or non-metallic materials used as a seal or seal component shall havea flammability spread index not exceeding 25 established per NFPA 255.

5) All fasteners used in sealing devices shall be Type 304 stainless steel.

6) Design of secondary seals shall permit the inspection of primary seals withoutremoval of the secondary seals.

7) Fabric seal in sealing devices that employ steel shoes in contact with the shell

may be installed after the hydrostatic test.

C.3.14 Gauging devices shall be provided per paragraph 3.8.15 of this specification.

C.3.15 Bonding Shunts

Bonding shunts shall be provided on floating roofs in accordance with JERSD-P-

0003and API RP 2003 requirements.


31/39



JERMS-D-3205




Page 31 of 39

Appendix G Structurally Supported Aluminum Dome Roofs

G.1 General

G.1.4 Special features

G.1.4.2 Exception

The aluminum dome roof materials shall have a mill finish.

G.2 Materials

G.2.1 General

Exception

Materials for all roof components shall be compatible with the intended service.

Alternate material for any roof component (structural frame, roof panels, node

covers, bolts, fasteners, sealant and gasket material, and skylight panels) shall not

be used without prior approval of the Company Representative, as defined in Section

3 of this specification.

G.2.3 Roof Panels

Exception

Roof panels and node covers shall be fabricated from Series 3000 (H32 or H34 temper) or

5000(H32 or H34 temper) aluminum with a minimum nominal thickness of 1.2 mm (0.05

in.).

G.2.4 Bolts and Fasteners

Exception

Bolts and fasteners shall be of 7075-T73 aluminum, 2024-T4 aluminum, or 300 Series

stainless steel (AISI 302 or AISI 304). Only 300 Series stainless steel (AISI 302 or AISI

304) bolts shall be used to attach aluminum to steel.

400 Series stainless steel or aluminized mild steel HV-Huck-Lock bolts shall be used for

joining structural members (struts) at the space truss nodes.

G.5 Roof Attachment

G.5.3 Separation of carbon Steel and Aluminum


32/39



JERMS-D-3205




Page 32 of 39

Exception

Aluminum shall be isolated from carbon steel by austenitic stainless steel spacers.

G.5.5 The dome surface paneling shall be designed as a watertight system under all design

load and temperature conditions. All edges of aluminum panels shall be covered,

sealed, and firmly clamped with batten in an interlocking manner to prevent slippingor disengagement under all load and temperature conditions.

G.8 Roof Vents

G.8.4.3 Surface appurtenances and closure panel joints shall be designed watertight without

the use of sealants.

G.10 Testing

G.10.2 100% liquid penetrant examinations shall be performed on structural welds and

components joined by welding.

G.11 Fabrication and Erection

G.11.5 Erection

Exception

Structural frame members (struts) shall be joined at nodes by preset-torque level HV-

HUCK-Lock bolts.

G.11.6 Workmanship

Exception

Sealant shall be applied and installed in a manner suitable to that of architectural class

work. Joint surfaces shall be clean to ensure adhesion of sealants. All exposed sealant

surfaces shall be tooled slightly concave after sealant is placed in joints. Misplaced excess

sealant shall be removed.


33/39



JERMS-D-3205




Page 33 of 39

Appendix H - Internal Floating Roofs

H.1 Scope

Exception

Types of internal floating roofs are limited to those specified in paragraph H.2.2 of this

specification. Other types stipulated or referenced in API 650, Appendix H shall not be

considered.

H.2 Types

H.2.1 Exception

The internal floating roof shall be selected by the design engineer.

H.2.2 Exception

Only type c(metallic pontoon roofs), type d(metallic double-deck roofs) or type

e(metallic roofs on floats) shall be used.

H.3 Material

H.3.1 Exception

The Design Engineer shall specify the materials required.

Internal floating roofs with non-metallic components as part of the floats are

prohibited.

H.3.2 Steel

Exception

Galvanized components shall not be used.

H.3.3 Aluminum

Exceptions

Aluminum shall not be used in services where caustic constituents are present in the stored

liquid.


34/39



JERMS-D-3205




Page 34 of 39

Delete reference to sandwich panel type.

H.4 Requirements for All Types

H.4.1 General

H.4.1.6 (Exception)

H.4.1.6.1 A minimum of four anti-static stranded stainless steel cables of minimum 3 mm indiameter, uniformly distributed, shall be provided from the fixed roof to the internal

floating roof. Design of the cables shall take into account strength, flexibility, joint

reliability and service life.

H.4.1.6.2 All moveable cover accessories (hatches, manways, pressure relief devices and otheropenings) on the internal floating roof shall be bonded to the internal floating roof to

prevent static electricity sparking when they are opened. The cable shall beminimum 3.2 mm (1/8) in diameter of stranded stainless steel, with a length at least

twice the normal travel of these device covers. Design of the cables shall take into

account strength, flexibility, joint reliability and service life.

H.4.1.8 Exceptions

All closed floating compartments shall be seal welded to prevent liquid or vapor

entry.

Delete reference to floating roof type H.2.2.g.

H.4.1.9 Delete this paragraph.

H.4.1.10 Exception

Drains for decks surfaces above the liquid level shall be designed to return any

spillage or condensate to the product. Such drains shall close automatically or

extended at least 100 mm (4 in.) into the product to minimize vapor loss.

H.4.2 INTERNAL FLOATING ROOF DESIGN

H.4.2.4 Delete reference to floating roof type H.2.2.g.

H.4.3 JOINT DESIGN


35/39



JERMS-D-3205




Page 35 of 39

H.4.3.3 Exception

Pivot joints that allow flexure between adjacent floats shall be provided on internal

floating roof designs that employ a metallic roof on tubular floats.

H.4.3.3.1 Exception

Only austenitic type stainless steel SS 304 hardware shall be used to join aluminum

and/or stainless components to each other or to carbon steel.

H.4.4 PERIPHERAL SEALS

H.4.4.2 The peripheral seal type and material shall selected by the Design Engineer.

H4.4.5 Seal Types

Exceptions

Any fabric or non-metallic materials used as a seal or seal component shall be selected

based on the design temperature, permeability, abrasion resistance, aging, flammability,

resistance to aromatics, and chemical resistance, and selected from the table in

paragraph C3.13.2 of this specification.

Only resilient foam-filled liquid-mounted and vapor-mounted rim seals shall be used.

Circumferential joints in envelope fabric seals shall overlap by at least 150 mm (6 in.). Galvanized steel components are prohibited.

All fabric or non-metallic materials used as a seal or seal component shall have a

flammability spread index not exceeding 25 established per NFPA 255.

H4.4.6 Fabric or non-metallic materials used as a seal or seal component shall be tested fortheir compatibility with the intended service by an independent laboratory.

H.4.5 ROOF PENETRATIONS

Exception

All roof penetrations shall be surrounded by a well that extends at least 100 mm (4

in.) into the stored liquid.

H.4.6 Roof Supports


36/39



JERMS-D-3205




Page 36 of 39

H.4.6.1 Exception

The floating roof shall be provided with fixed or adjustable supports.

H4.6.2 Exception

The height of the floating roof shall be adjustable to two positions with the tank out

of service. The design of the supports shall prevent damage to the fixed roof and

floating roof at the tank maximum design liquid level.

H.4.6.3 Exception

The high (maintenance) of adjustable roof supports position shall provide a 2 m (79foot) clearance between the lowest portion of the roof and the tank floor.

H.4.6.4 Exception

Delete reference to floating roof types H.2.2.a, b and g.

H.4.6.5 Exception

Drainable pipe supports shall be used.

H.4.6.6 Exception

Steel bearing plates shall be provided under all support legs so as to distribute the

weight of the internal floating roof on the tank bottom plates and to avoid damage to

internal tank coatings. The bearing plates shall be twice the diameter of the support

section, 12.7 mm ( inch) thick, and shall be attached to the bottom by 4.8 mm (3/16

inch) continuous fillet welds.

H.4.6.9 Where propeller-type mixers are used, the support legs shall provide a minimum

clearance of 300 mm (12 inch) from the underside of the internal floating roof to thetop of the mixer paddle(s).

H.4.6.10 Jet-nozzle mixers are not permitted.

H.5 OPENINGS AND APPURTENANCES

H.5.2 Vents

H.5.2.1 Pressure-Vacuum (Bleeder) Vents


37/39



JERMS-D-3205




Page 37 of 39

Exception

As a minimum, two overpressure/vacuum bleeder type vents shall be installed in the

internal floating roof. Vents shall be sized to handle a total of 125% of the maximum

filling/withdrawal rates that are specified on the Storage Tank Data Sheet.

Commentary Note:

Bleeder vents shall be designed to open and close automatically when the roof is 75 mm (3

inch) above its low support legs position upon emptying and filling the tank, respectively.

H.5.2.2 Tank Circulation Vents

H5.2.2.1 Exception

Peripheral circulation vents shall be located at the top of the shell with an outward

projecting cover. Air intake shall be from the cover bottom side to minimize dust

ingress.

H.5.2.2.4 Circulation venting and venting devices shall provide protection against

overpressure/vacuum for normal conditions (resulting from operational requirementsand atmospheric changes) and emergency conditions (resulting from exposure to an

external fire) according to API STD 2000.

H5.2.3 Vents for protection against overpressure/vacuum, while the roof is floating, shall be

provided as follows:

1) Vents shall be sized according to API STD 2000 requirements, considering25% of the filling/emptying rates and 100% of thermal breathing.

2) Vents shall be evenly distributed and close to the roof edge with enough vents

shall be provided close to the inlet diffuser in services where gas slugs are

expected.

3) Vents shall be designed so as not to allow any carry over of stored liquid ontothe floating roof.

Commentary Note:

Anticipated operation upset conditions such as an increase in temperature of the input

stream to a tank or chemical injection that will result in vaporization beyond that associated

with the product true vapor pressure design limit of 90 kPa absolute (13 psia) or gas purges

shall be also considered in determining the required venting capacity.


38/39



JERMS-D-3205




Page 38 of 39

H.5.5.3 Inspection Hatches

Exception

Inspection hatches shall be located on the fixed roof to permit visual inspection of the

seal region.

H.5.6 Inlet Diffuser

Exception

Inlet diffuser shall be specified according to paragraph 3.8.12 of this specification.

H5.7 Gauging And Sampling Devices

Exception

Internal floating roofs shall be provided with gauging and sampling devices when specified

by the Design Engineer.

H.6 Fabrication, Erection, Welding, Inspection, and Testing

H.6.4 Exception

Floatation test and initial fill inspection shall be performed by the erector andwitnessed by the purchaser.

H.6.4.1 Exception

Delete reference to floating roof types H.2.2.a, b, g and f.

H.6.4.3 Exception

Potable water having less than 500 ppm chlorides shall be used for testing when the

internal floating roof is constructed of aluminum or stainless steel.

H.6.5 Internal floating roof components that are fabricated or attached by welding, such asclips, gusset plates, etc., shall be completely seal-welded.

H.6.6 Shop Fabrication

H.6.6.1 Straightening of material shall be done by pressing or other non-injurious methods

before the material is laid out or worked on in any way. Materials shall not behammered.


39/39



JERMS-D-3205


H.6.6.2 When the edges of plates are cut with a torch, the resulting surface shall be uniform,smooth, and free from scale and slag before performing any welding.

H.6.7 Shop Inspection and Testing

H.6.7.1 Internal floating roofs manufactured in accordance with this specification are subject

to verification by the Company Inspector in accordance with Company InspectionRequirements Form 175-324900.

H.6.7.2 Inspection at the mill, shop, or fabrication yard shall not release the manufacturer ofthe internal floating roof from responsibility for repairing or replacing any defective

material or workmanship that may be subsequently discovered in the field.

H.6.7.3 All support brackets that are welded to tubular pontoons shall be dye-penetrantinspected.

H.6.7.4 Welded tubular pontoons shall be pneumatically pressure tested with air at 35 kPa (5

psig) and the welds visually inspected by using a soapy water solution or by

immersing the pontoons under water. All defective welds shall be repaired and the

pontoons re-tested prior to shipment.

H.7 Installation

H.7.1 Internal floating roofs shall be installed by contractors who have been approved bythe manufacturer of the internal floating roofs.

H.7.2 Internal floating roofs shall be installed in accordance with the procedures specifiedby the internal floating roof manufacturer.

H.8 Drawings and Calculations

The internal floating roof manufacturer shall prepare drawings, calculations, and datain accordance with Form NMR-7918-2, Nonmaterial Requirements. Drawings and

calculations that are approved by the Design Engineer shall not relieve the internal

floating roof manufacturer of the responsibility to comply with API STD 650 and

this specification.

jerms-d-3205 manufacture of atmospheric tanks

Documents