USACE / NAVFAC / AFCESA / NASA UFGS-33 56 13.13 (October 2005)
------------------------------
Preparing Activity: NAVFAC Replacing without change
UFGS-13205 (October 2005)
UNIFIED FACILITIES GUIDE SPECIFICATIONS
References are in agreement with UMRL dated January 2009
SECTION 33 56 13.13
STEEL TANKS WITH FIXED ROOFS
04/06
NOTE: This guide specification covers the requirements for design and installation
of aboveground steel tanks with fixed cone roofs.
Edit this guide specification for project specific requirements by adding, deleting,
or revising text. For bracketed items, choose applicable items(s) or insert
appropriate information.
Remove information and requirements not required in respective project, whether
or not brackets are present.
Comments and suggestions on this guide specification are welcome and should
be directed to the technical proponent of the specification. A listing of technical
proponents, including their organization designation and telephone number, is
on the Internet.
Recommended changes to a UFGS should be submitted as a Criteria Change Request
(CCR).
NOTE: Tanks with fixed roofs are usually used for the storage of products having
a true vapor pressure less than 10.3 kPa 0.5 psi, JP-5, diesel fuel, kerosene,
and burner fuel oils. Earthwork, concrete work, piping, and other work in connection
with the tanks should be included in the appropriate sections of the project
specification or in a separate project specification.
NOTE: The following information shall be shown on the project drawings:
1. The extent of the work included in the project should be indicated on drawings
showing the site layout, location of outlets and inlets, water drawoff connection,
manholes, other tank appurtenances, and other data required for design by the
Contractor.
2. If concrete foundation work is provided under a separate contract, Government
work should include foundations, setting anchor bolts, concrete retaining ring,
and other pertinent work such as sand for sand cushion, water for testing, and
furnishing and installing any tank accessories not a part of this specification.
PART 1 GENERAL
1.1 REFERENCES
NOTE: This paragraph is used to list the publications cited in the text of
the guide specification. The publications are referred to in the text by basic
designation only and listed in this paragraph by organization, designation,
date, and title.
Use the Reference Wizard's Check Reference feature when you add a RID outside
of the Section's Reference Article to automatically place the reference in the
Reference Article. Also use the Reference Wizard's Check Reference feature
to update the issue dates.
References not used in the text will automatically be deleted from this section
of the project specification when you choose to reconcile references in the
publish print process.
The publications listed below form a part of this specification to the extent referenced. The publications are
referred to within the text by the basic designation only.
[AMERICAN PETROLEUM INSTITUTE (API)API MPMS 2.2A(1995; R 2007) Manual of Petroleum Measurement Standard Chapter 2 - Tank Calibration Section 2A - Measurement and Calibration of Upright Cylindrical Tanks by the Manual Tank Strapping MethodAPI MPMS 2.2B(1989; R 2007) Manual of Petroleum Measurement Standards Chapter 2 - Tank Calibration Section 2B - Calibration of Upright Cylindrical Tanks Using the Optical Reference Line MethodAPI RP 2009(2002) Safe Welding, Cutting, and Hot Work Practices in the Petroleum and Petrochemical IndustriesAPI Spec 6D(2008; Errata 2008; Errata 2008) Specification for Pipeline ValvesAPI Std 2000(1998; Errata 1999) Venting Atmospheric and Low-Pressure Storage Tanks: Nonrefrigerated and RefrigeratedAPI Std 650(2007; Errata 2008) Welded Steel Tanks for Oil Storage][ASME INTERNATIONAL (ASME)ASME B16.11(2005) Forged Fittings, Socket-Welding and ThreadedASME B16.21(2005) Nonmetallic Flat Gaskets for Pipe FlangesASME B16.5(2003) Standard for Pipe Flanges and Flanged Fittings: NPS 1/2 Through NPS 24ASME B16.9(2007) Standard for Factory-Made Wrought Steel Buttwelding Fittings][ASTM INTERNATIONAL (ASTM)ASTM A 182/A 182M(2008a) Standard Specification for Forged or Rolled Alloy-Steel Pipe Flanges, Forged Fittings, and Valves and Parts for High-Temperature ServiceASTM A 193/A 193M(2008b) Standard Specification for Alloy-Steel and Stainless Steel Bolting Materials for High-Temperature ServiceASTM A 194/A 194M(2008b) Standard Specification for Carbon and Alloy Steel Nuts for Bolts for High-Pressure or High-Temperature Service, or BothASTM A 216/A 216M(2008) Standard Specification for Steel Castings, Carbon, Suitable for Fusion Welding, for High-Temperature ServiceASTM A 269(2008) Standard Specification for Seamless and Welded Austenitic Stainless Steel Tubing for General ServiceASTM A 312/A 312M(2008a) Standard Specification for Seamless, Welded, and Heavily Worked Austenitic Stainless Steel PipesASTM A 351/A 351M(2006) Standard Specification for Castings, Austenitic, Austenitic-Ferritic (Duplex), for Pressure-Containing PartsASTM A 403/A 403M(2007a) Standard Specification for Wrought Austenitic Stainless Steel Piping FittingsASTM A 492(1995; R 2004) Standard Specification for Stainless Steel Rope WireASTM B 209(2007) Standard Specification for Aluminum and Aluminum-Alloy Sheet and PlateASTM B 209M(2007) Standard Specification for Aluminum and Aluminum-Alloy Sheet and Plate (Metric)ASTM C 33(2007) Standard Specification for Concrete AggregatesASTM C 88(2005) Standard Test Method for Soundness of Aggregates by Use of Sodium Sulfate or Magnesium SulfateASTM D 2565(1999; R 2008) Xenon Arc Exposure of Plastics Intended for Outdoor ApplicationsASTM D 3389(2005) Coated Fabrics Abrasion Resistance (Rotary Platform, Double-Head Abrader)ASTM D 3453(2007) Flexible Cellular Materials - Urethane for Furniture and Automotive Cushioning, Bedding, and Similar ApplicationsASTM D 396(2008b) Standard Specification for Fuel OilsASTM D 471(2006; R 2008) Standard Test Method for Rubber Property - Effect of LiquidsASTM D 4814(2008b) Automotive Spark-Ignition Engine FuelASTM D 543(2006) Standard Practices for Evaluating the Resistance of Plastics to Chemical ReagentsASTM D 747(2008) Apparent Bending Modulus of Plastics by Means of a Cantilever BeamASTM D 751(2006) Coated FabricsASTM E 96/E 96M(2005) Standard Test Methods for Water Vapor Transmission of Materials][NACE INTERNATIONAL (NACE)NACE SP0178(2007) Fabrication Details, Surface Finish Requirements, and Proper Design Considerations for Tanks and Vessels to be Lined for Immersion Service][NATIONAL FIRE PROTECTION ASSOCIATION (NFPA)NFPA 11(2005; Amendment 1 2006; Amendment 2 2007) Low-, Medium- and High- Expansion Foam SystemsNFPA 70(2007; AMD 1 2008) National Electrical Code - 2008 Edition][U.S. DEPARTMENT OF DEFENSE (DOD)MIL-DTL-38219(Rev D) Turbine Fuel, Low Volatility, JP-7MIL-DTL-5624(Rev U; Notice 1) Turbine Fuel, Aviation, Grades JP-4 and JP-5MIL-DTL-83133(Rev F) Turbine Fuels, Aviation, Kerosene Types, NATO F-34 (JP-8), NATO F-35 and JP-8 + 100MIL-P-24396(Rev A) Packing Material, Braided PTFE (Polytetrafluoroethylene)MIL-PRF-907(Rev F) Antiseize Thread Compound, High TemperatureMIL-R-6855(Rev E; Notice 2; Supp 1) Rubber, Synthetic, Sheets, Strips, Molded or Extruded ShapesMIL-R-83248(Rev C; Notice 1; Notice 2) Rubber, Fluorocarbon Elastomer, High Temperature, Fluid, and Compression Set ResistantMIL-V-12003(Rev F; Am 1; CANC Notice 1) Valves, Plug, Cast-Iron or Steel, Manually Operated][U.S. GENERAL SERVICES ADMINISTRATION (GSA)FS A-A-52557(Rev A)) Fuel Oil, Diesel; for Posts, Camps and StationsFS SS-S-1614(Rev A; Am 1) Sealants, Joint,Jet-Fuel-Resistant, Hot-Applied, for Portland Cement and Tar Concrete PavementsFS SS-S-200(Rev E; Am 2) Sealant, Joint, Two-Component, Jet-Blast-Resistant, Cold-Applied, for Portland Cement Concrete Pavement][U.S. NATIONAL ARCHIVES AND RECORDS ADMINISTRATION (NARA)29 CFR 1910.23Guarding Floor and Wall Openings and Holes29 CFR 1910.24Fixed Industrial Stairs29 CFR 1910.27Fixed Ladders][U.S. NAVAL FACILITIES ENGINEERING COMMAND (NAVFAC)NAVFAC P-355(1992) Seismic Design for Buildings][UNDERWRITERS LABORATORIES (UL)UL 698(2006) Industrial Control Equipment for Hazardous (Classified) LocationsUL 886(1994; Rev thru Nov 2005) Outlet Boxes and Fittings for Use in Hazardous (Classified) Locations]1.2 SUBMITTALS
NOTE: Review submittal description (SD) definitions in Section 01 33 00 SUBMITTAL
PROCEDURES and edit the following list to reflect only the submittals required
for the project. Submittals should be kept to the minimum required for adequate
quality control.
A “G” following a submittal item indicates that the submittal requires Government
approval. Some submittals are already marked with a “G”. Only delete an existing
“G” if the submittal item is not complex and can be reviewed through the Contractor’s
Quality Control system. Only add a “G” if the submittal is sufficiently important
or complex in context of the project.
For submittals requiring Government approval on Army projects, a code of up
to three characters within the submittal tags may be used following the "G"
designation to indicate the approving authority. Codes for Army projects using
the Resident Management System (RMS) are: "AE" for Architect-Engineer; "DO"
for District Office (Engineering Division or other organization in the District
Office); "AO" for Area Office; "RO" for Resident Office; and "PO" for Project
Office. Codes following the "G" typically are not used for Navy, Air Force,
and NASA projects.
Choose the first bracketed item for Navy, Air Force and NASA projects, or choose
the second bracketed item for Army projects.
Government approval is required for submittals with a "G" designation; submittals not having a "G" designation
are [for Contractor Quality Control approval.][for information only. When used, a designation following the
"G" designation identifies the office that will review the submittal for the Government.] The following shall
be submitted in accordance with Section 01 33 00 SUBMITTAL PROCEDURES:
SD-02 Shop Drawings
Steel tank
Floating pan
Aluminum dome roof
Tracer gas detection system drawings
SD-03 Product Data
Structural steel
Pipe and fittings
Flange bolting
Gaskets
Mastic seal
Floating pan
Gage hatch
Mechanical tape level gage
Servo level gage
Plug (double block and bleed) valves
Level alarm system
High liquid level control valve
Thermometers
Sand cushion
Venting
Grating or anti-slip floor plate for stairway
Roof manholes
Shell access holes
Drain pump
Tracer gas detection system
Aluminum dome roof
Flexible membrane liner (FML)
Oil-resistant coating system
SD-04 Samples
FML Samples
SD-05 Design Data
Steel tank design calculations
Floating pan design
Aluminum dome roof design calculations
SD-06 Test Reports
Structural steel tests (including toughness test data)
FML inspections
FML tests
FML factory test
Sand cushion tests
Fire test
SD-07 Certificates
Welding procedures and procedure qualifications
Qualifications of nondestructive test examiners
Tank calibration experience
Qualifications of FML field engineer
FML Manufacturer's Representative
SD-08 Manufacturer's Instructions
Mechanical tape level gage
Servo level gage
Level alarm system
High liquid level control valve
Aluminum dome roof
Flexible membrane liner (FML)
SD-10 Operation and Maintenance Data
Mechanical tape level gage, Data Package 2[; G][; G, [_____]]
Servo level gage, Data Package 2[; G][; G, [_____]]
Level alarm system, Data Package 2[; G][; G, [_____]]
High liquid level control valve, Data Package 2[; G][; G, [_____]]
Venting, Data Package 2[; G][; G, [_____]]
Submit in accordance with Section 01 78 23 OPERATION AND MAINTENANCE DATA.
SD-11 Closeout Submittals
Tank calibration record
Weld inspection reports
Submit reports for inspection of welds, and radiographs [, to the Contracting Officer].
1.3 COPIES OF API PUBLICATIONS
Provide four copies of API RP 2009, API Std 650, API Std 2000, and[ API MPMS 2.2A][ API MPMS 2.2B].
1.4 RELATED REQUIREMENTS
Materials, design, fabrication, welding, erection, testing, and appurtenances shall be in accordance with API Std 650
and API Std 2000, except as otherwise specified herein. Products to be stored in the tank are JP-5, diesel
fuel, [_____,] and fuel oil. Section 23 03 00.00 20 BASIC MECHANICAL MATERIALS AND METHODS, applies to this
section except as specified otherwise.
1.5 DESIGN REQUIREMENTS
NOTE: Insert design information for loads on tanks as given in MIL-HDBK-1002/2.
General information on tanks can be obtained from DM-22. Insert the size and
volume of the tank. Edit as required for project.
Tank shall be designed to resist the following loads and forces:
a. Wind: [_____] kilometers per hour [_____] mph
b. Seismic Zone: [_____]
c. Roof Live Load: [_____] kPa [_____] pounds per square foot
d. The following combinations of loads, with corresponding percentages of basic stresses to
be used in design, shall be allowed:
Load Combination Percentage of Allowable Stress
Dead load + live load 100
Dead load + live load + wind load 133
Dead load + live load + seismic load 133
e. Determine forces and hydrodynamic effects from seismic loading in accordance with API Std 650
and NAVFAC P-355. Design tank to provide freeboard to minimize or prevent overflow and damage
to the roof and upper shell that may be caused by sloshing of the liquid contents. Design columns
to resist the forces caused by sloshing of the liquid contents.
f. The usable capacity of the tank shall be not less than [_____] liters 42.0 U.S. standard
gallons barrels. The tank shall be not more than [_____] m feet in diameter, and shall be approximately
[_____] m feet in height plus additional height for sloshing due to seismic effects.
g. Allowable solid bearing capacity of [_____] with minimum foundation embedment of [610] [____]
mm [24] [_____] inches. Differential settlement of up to [100] [____] mm [4] [_____] inches
under dynamic seismic loading. Bearing values may be increased on third for temporary wind
and seismic loads. Allowable passive lateral soil pressure of [_____]. Coefficient of friction
of [0.4] [_____] N.
h. Specify gravity of liquid is [0.84] [_____].
i. Design tank and connected piping to accommodate external piping loads in accordance with
API Std 650, Appendix P.
j. Tank interior columns, when provided, shall be of pipe or round structural tubing.
1.5.1 Corrosion Allowance
NOTE: Corrosion allowance shall not be less than 1.6 mm 1/16 inch for coated
tanks. For uncoated tanks, calculate corrosion metal loss and select appropriate
corrosion allowance.
Make allowance of [1.6] [_____] mm [1/16] [_____] inch in thickness of steel for corrosion loss. Corrosion allowance
shall be applied to the [interior] [and] [exterior] of the shell, roof, and to surfaces of interior structural
members.
1.5.2 Design Metal Temperature
NOTE: Insert design metal temperature for locations not covered by API Std
650. Obtain low temperature from weather data.
API Std 650 [[_____] degrees C] [[_____] degrees F].
1.6 TANK CALIBRATION EXPERIENCE
Perform calibration of the tank using a qualified organization that can certify to at least 2 years of prior
successful and accurate experience in calibrating tanks of comparable type and size.
1.7 ELECTRICAL WORK
NOTE: Insert appropriate Section number and title in blank below using format
per UFC 1-300-02.
Electrical equipment and wiring shall be in accordance with [_____]. Switches and devices necessary for controlling
the electrical equipment shall be provided. Wiring, equipment, and fittings shall be explosion-proof in conformance
with the applicable requirements of UL 698 and UL 886 for Class I, Division 1, Group C and D hazardous locations.
Electrical installations shall conform to the requirements of the NFPA 70. Underground electrical wiring shall
be enclosed in PVC coated conduit which shall be isolated from steel tanks with dielectric fittings.
1.8 QUALIFICATIONS OF FML FIELD ENGINEER
NOTE: Include any local regulatory requirements that must be met by the Contractor.
The Contractor shall meet the licensing requirements of the State in which the work is to be performed. The
Contractor shall provide a field engineer full time to this project. The field engineer shall have successfully
completed manufacturer's training for handling and installing FML systems as well as have at least 92,950 square
meter one million square feet of installation experience.
1.9 QUALITY ASSURANCE
1.9.1 Drawing Requirements
Drawings for the steel tank [,floating pan] [,and aluminum dome roof] shall be prepared by a registered structural
engineer. Include erection diagrams and detail drawings of tank bottoms and foundations, roof, shell plates,
wind girders, and openings and connections for fittings and appurtenances. The drawings shall include the following:
a. Tank erection details showing dimensions, sizes, thickness, gages, materials, finishes,
and erection procedures.
b. Tank component details to include as a minimum:
(1) Sand cushion
(2) Floating pan (including details of support legs, manways, foam dams, joint attachments,
anti-rotation cable, and grounding cables)
(3) Internal pipe and fittings
(4) Locations of floating pan pressure/vacuum vents, rim seals, and foam dam
(5) Details of AFFF fire protection system components
(6) Location of alarm and control switches
(7) Location of gages
c. Details of the base of any component that sets on grades; complete with attachments, anchor
bolt templates, and recommended clearances for maintenance and operation.
d. Details of the electric wiring indicating applicable single line and wiring diagrams with
written description of sequence of operation and the instrumentation.
e. Details showing the location, type, and description of vibration isolation devices for all
applications.
f. Complete piping and wiring schematic diagrams.
1.9.2 Tracer Gas Detection System Drawings
Provide shop drawings for installation of the tracer gas detection system.
1.9.3 Data Requirements
Calculations for the steel tank design [,floating pan design] [,and aluminum dome roof design] shall be prepared
by a registered structural engineer. Include calculations that indicate the maximum and minimum operating pressures
in accordance with API Std 650, Appendix F. [Include calculations for the buoyancy of the floating pan and the
structural stability of the floating pan when resting on the support legs.]
1.9.4 Test Examiners
Submit proof of compliance of nondestructive test examiners with API Std 650. Submit certified data on tank
calibration experience.
1.9.5 Qualifications of FML Field Engineer
Submit a letter providing evidence of the Contractor's and the field engineer's experience, training, and licensing.
Statements of previous FML job experience shall be provided with a point of contact, a phone number, address,
the type of installation, and the current status of the installation.
1.9.6 FML Manufacturer's Representative
Submit a letter, prior to placing the FML, from the FML manufacturer naming their authorized representative complete
with their address, phone number, and a point of contact.
PART 2 PRODUCTS
2.1 MATERIALS
Conform to the following requirements except that materials not definitely specified shall conform to API Std 650
.
2.2 STRUCTURAL STEEL
API Std 650.
2.3 PIPE, FITTINGS, AND FLANGES
API Std 650, except as specified. Fittings less than 50 mm 2 inches IPS shall be flanged or threaded; sizes
50 mm 2 inches IPS and larger shall be flanged or butt-welded. Flanges shall be welding neck type in accordance
with ASME B16.5. Threaded fittings shall conform to ASME B16.11, 20.7 MPa 3000 lb. Butt welding fittings shall
conform to ASME B16.9.
2.3.1 Inlet and Outlet Piping, Fuel Storage Tanks
NOTE: Specify stainless steel piping for aviation fuel operating storage tanks
at naval air stations.
Stainless Steel for Inlet and Outlet of Aviation Fuel Operating Storage Tanks:
2.3.1.1 Pipe
ASTM A 312/A 312M, Schedule 40, Type 304L or 316L.
2.3.1.2 Fittings
a. Butt welding: ASTM A 403/A 403M, Class WP, Schedule 40, Type 304L or 316L.
b. Threaded: ASME B16.11, Class 20.7 MPa 3000 lb, ASTM A 182/A 182M, Type 304L or 316L, forged.
2.3.1.3 Flanges
ASME B16.5, Class 150, ASTM A 182/A 182M, Type 304L or 316L.
2.3.1.4 Flange Bolting
Bolts: ASTM A 193/A 193M, Grade B7; nuts: ASTM A 194/A 194M, Grade 7.
2.4 PIPE FLANGE GASKETS
ASME B16.21, spiral-wound type.
2.5 GASKETS FOR MANHOLES, CLEANOUTS, AND COVERS
2.5.1 Flanged and Bolted Connections and Covers
Provide composition asbestos-free, fire-resistant gaskets.
2.5.2 Roof Manhole Frames and Covers
Provide rubber gaskets, MIL-R-6855, for covers which are not bolted.
2.6 MASTIC SEAL
Mastic seal for sealing foundation ring wall shall be resistant to jet fuel and shall conform to FS SS-S-200
for cold applied sealant and FS SS-S-1614 for hot applied sealant.
2.7 INTERIOR PROTECTIVE COATING SYSTEM
NOTE: In order to protect product quality and to extend the life of the tank,
the prescribed interior surfaces of steel petroleum storage tanks shall be coated
in accordance with MIL-HDBK-1022 "Petroleum Fuel Facilities."
NOTE: Other guidance as to interior surface treatment is as follows:
1. Specify bare interior metal surfaces if coating is not required, or if the
coating is to be done at a later date. Uncoated surfaces shall be cleaned of
contaminants, including mill scale. Delete reference to Section 09 97 13.15
if not applicable.
2. Coating with SAE-30 weight oil should be specified when the surfaces in
contact with the stored product are to be left bare, and the tank will not be
placed in service immediately.
[Section 09 97 13.15 INTERIOR COATING OF WELDED STEEL PETROLEUM FUEL TANKS.] [Interior of the tank shall be bare
steel. Coat interior of tank with SAE 30 oil for temporary protection.]
2.8 EXTERIOR PROTECTIVE COATING SYSTEM
Section 09 97 13.27 EXTERIOR COATING OF STEEL STRUCTURES.
2.9 APPURTENANCES
2.9.1 Floating Pan
The floating pan shall be naturally buoyant by means of sealed honeycomb cells in aluminum sandwich panels, be
suitable for operation with liquids having a specific gravity of 0.70, be internal to the tank, have full surface
contact with the fuel, be equipped with a seal at each penetration, and meet the requirements of API Std 650
Appendix H. A rim shall be provided around the floating pan periphery and extend a minimum of 150 mm 6 inches
above the free liquid surface. The rim shall contain turbulence and prevent fuel from splashing up onto the
top surface of the floating pan.
2.9.1.1 Pan Integrity
The floating pan shall support the following loading conditions without causing damage to the pan, sinking the
pan, or allowing product to spill onto the top surface of the pan in the event the pan is punctured.
a. A uniform load of three times the weight of the pan.
b. For tanks larger than 9144 mm 30 feet in diameter, a point load of 227 kg on a 93,000 sq
mm 500 pounds on a one square foot area anywhere on the floating pan while it is floating or
resting on the legs.
c. For tanks 9144 mm 30 feet in diameter and less, a point load of 113 kg on a 93,000 sq mm
250 pounds on a one square foot area anywhere on the floating pan while it is floating or resting
on the legs.
2.9.1.2 Joint Connections
Aluminum sandwich panels shall be joined together by means of a gasketed joint that transmits loads without structural
failure or leakage.
2.9.1.3 Aluminum Extrusions
Extrusions shall be made from alloy 6063-T6 in accordance with ASTM B 209M ASTM B 209.
2.9.1.4 Aluminum Sandwich Panels
Panels shall be made from alloy 3003 H14, 3003 H16, 3105 H14, or 5010 H24 in accordance ASTM B 209M ASTM B 209
. The skin of the panels shall have a minimum thickness of 0.356 mm 0.014 inches. The core of the panels shall
be 25 mm one inch aluminum honeycomb.
2.9.1.5 Support Legs
Floating pan shall be provided with two position self-draining legs that are designed to support a uniform load
of 600 Pa 12.5 pounds per square foot. The legs shall be tubular structural members at least 50 mm 2 inches
in diameter and ride with the pan when the fuel level is above the high position. The low position shall be
900 mm 36 inches and high position 1900 mm 75 inches. The exact location and number of the support legs shall
be as recommended by the floating pan manufacturer. The legs shall be capable of allowing a person, standing
on top of the floating pan while the tank is in service, to perform the following functions:
a. Change from the high to the low position.
b. Change from the low to the high position.
c. Completely remove the legs.
d. Adjust the legs vertically a distance equal of plus or minus 75 mm 3 inches.
2.9.1.6 Periphery Seals
Periphery seals shall be made of flexible polyurethane foam in accordance with ASTM D 3453 and be covered with
a polyurethane coated polyester fabric wrap at least 0.635 mm 0.025 inch thick. The periphery seal shall fit
the space between the tank shell and the outer edge of the floating pan with two flexible seals, a primary and
a secondary. The seals, primary and secondary as a unit, shall accommodate a deviation between the path of the
floating pan relative to the tank shell of an additional 100 mm 4 inches of compression and an additional extension
of 50 mm 2 inches from its normal compressed position at any fluid level. The primary seal shall be above the
liquid level and be free draining without trapping any liquid. The secondary seal shall be above the primary
seal. Seals shall be capable of being replaced during tank operations, be durable in the tank's environment,
be abrasion resistant, and not discolor or contaminate the liquid stored in the tank.
2.9.1.7 Penetration Seals
Penetration seals shall be made of Buna-N. Vertical appurtenances such as columns, ladders, cable, etc. that
penetrate the floating pan shall have seals that permit a local deviation of plus or minus 125 mm 5 inches and
have a rim that extends a minimum of 150 mm 6 inches above the free liquid to contain product turbulence and
prevent the tank product from splashing up onto the top surface of the floating pan.
2.9.1.8 Manway
A manway shall be provided for each floating pan to provide access to the tank interior when the floating pan
is on its supports and the tank is empty. Manway shall have an clear inside diameter of at least 760 mm 30 inches
. The cover shall be bolted fuel tight to the floating pan with a Buna-N gasket. Manway shall have a rim that
extends a minimum of 75 mm 3 inches above the free liquid to contain product turbulence and prevent the tank
product from splashing up onto the top surface of the floating pan.
2.9.1.9 Foam Dam
NOTE: Provide foam dam for all tanks. Do not delete for smaller tanks as done
in COE specifications.
A foam dam shall be constructed of steel plate and mounted directly to the top of the floating pan. The steel
dam shall be supported by steel channels as indicated. The dam shall be constructed in accordance with NFPA 11
.
2.9.1.10 Grounding Cables
Two or more 3 mm 1/8 inch diameter grounding cable made of 304 stainless steel aircraft cable conforming to ASTM A 492
, with a maximum resistance of 8.5 ohms per 30.48 meters 100 feet shall be provided for each tank. The exact
location and number of grounding cables shall be as recommended by the floating pan manufacturer.
2.9.1.11 Anti-Rotation Cable
One 6 mm 1/4 inch diameter anti-rotation cable made of 304 stainless steel conforming to ASTM A 492 shall be
provided for each tank. Fittings for anti-rotation cables including cable clamps, pins, sockets, turnbuckles,
U-bolts and nuts, etc. shall be 304 stainless steel. Cable shall be made taut by means of the turnbuckle. The
exact location of the anti-rotation cable shall be as recommended by the floating pan manufacturer.
2.9.1.12 Fire Test
The floating pan design shall be fire tested by both of the following tests being applied to a test floating
pan. Float the test floating pan in aviation turbine fuel or motor gasoline with a flash point of less than
120 degrees F. Successful conclusion of each fire test shows that the design is adequate if no significant damage
occurs to the pan, the pan continues to float, and the fire did not spread to the whole surface of the fuel.
a. Hole Fire: The test floating pan shall have a 300 mm 12 inch or larger diameter hole cut
through it. After being lit, the fuel in the hole shall burn for a minimum of 2 hours.
b. Rim Fire: After being lit, the fuel around the test rim section shall burn for a minimum
of 2 hours.
2.9.2 Gage Hatch
Provide gage hatch and stilling well to within 75 mm 3 inches of the bottom of the tank for manual gauging.
Provide a horizontal datum plate of 6 mm 1/4 inch thick stainless steel at the bottom of the stilling well with
the top of the plate at the elevation at which the shell intersects the bottom. Equip hatch with a self-closing,
foot-operated, lockdown cover of nonferrous metal. Provide gasket for dissimilar metal protection. Provide
a thermometer holder. Locate hatch near roof manhole, readily accessible from the top platform of the stairway.
2.9.3 Mechanical Tape Level Gage
NOTE: Delete this paragraph if Servo Level gages are specified.
The mechanical tape gage shall be complete with all necessary incidental pipe, pulleys, fittings, supports, support
brackets, tension spring, and guide wire assemblies. The gage shall automatically provide the location of the
floating pan within plus or minus 1.6 mm 1/16 inch of the actual liquid level. The head shall be made of aluminum
and be mounted on the exterior of the tank shell approximately 1370 mm 54 inches above the tank bottom. The
head shall contain a glass covered window complete with an inside wiper. The seals shall be made of teflon.
The shafts, graduated tape, and tape drum assembly shall be made of stainless steel. The tape shall be of sufficient
length to measure the liquid level from the bottom to the top of the storage tank. Gage measurements shall be
graduated in 1.6 mm 1/16 inch increments. The tape shall be carried over pulleys housed in elbow assemblies
at each change of direction. For data transmission, the mechanical tape gage head shall be provided with a direct
gear, non-contacting optical digital encoder coupled to the gage shaft. Transmitter shall provide a 4-20 MA
signal to a remote digital receiver/indicator. Transmitter shall be powered from the remote receiver. Encoder/transmitter
shall be UL listed and/or FM approved as intrinsically safe for use in a Class I, Division 1, Groups C and D,
hazardous environment.
2.9.4 Servo Level Gage
NOTE: Delete this paragraph if Mechanical Tape gages are specified.
2.9.4.1 Construction
The materials of construction of the servo level gage, excluding "O" ring gaskets, magnetics, and electronic
components, shall be constructed of either ASTM A 351/A 351M Type 316 stainless steel or cast aluminum. "O"
ring gaskets shall be constructed of Buna-N. The servo level gage shall be Underwriters Laboratory (UL) or Factory
Mutual (FM) labeled for Class I, Division 1, Group D hazardous areas, and shall have maximum temperature rating
of "T2D" 215 degrees C 419 degrees F as defined by NFPA 70. The nameplate shall include the temperature rating.
Unit shall be provided with a thermostatically controlled heater for prevention of condensation and freeze protection
and an RTD and self compensating temperature converter. Unit shall receive 120 volts, single phase power and
shall consume 60 VA, maximum.
2.9.4.2 Assembly
The automatic tank level gage assembly shall include a servo level gage, an ASTM A 492 Type 316 stainless steel
measuring wire, an unguided 146 mm 5.7 inch diameter type 316 stainless steel displacer, an aluminum calibration
chamber, local and remote level indications, and an aluminum stilling well. The measuring wire shall be of sufficient
length to measure the liquid level from the bottom to the top of the storage tank.
2.9.4.3 Gage Operation
The displacer shall indicate to the servo level gage a rise or fall in the liquid level of the tank. The servo
level gage shall be capable of sensing any movement of the displacer and provide both a local and a remote liquid
level indication. The servo level gage shall have a measuring accuracy of plus or minus 3 mm 0.01 feet.
2.9.4.4 Data Transmission
When the servo level gage senses a rise or fall in the tank liquid level, the internal processor shall be capable
of providing serialized output capable of being transmitted over a two-wire bus to remote receiver/indicator
units. The units of measurement shall be millimeters feet and measuring increments shall be 3 mm in hundredths
(0.01) of a foot. Wave integration time shall be 1 to 10 seconds, adjustable.
2.9.5 Plug (Double Block and Bleed) Valves
API Spec 6D and MIL-V-12003 Type III, ANSI Class 150, nonlubricated, resilient, double seated, tapered lift,
plug type capable of handling two-way shutoff; steel body, chrome-plated interior, and tapered plug of steel
or ductile iron, chrome or nickel plated, supported on upper and lower trunnions, and steel or ductile iron,
sealing slips, with Viton seals. Valve design shall permit sealing slips to be replaced from the bottom with
the valve mounted in the piping. Valves shall operate from fully open to fully closed by rotation of the handwheel
to lift and turn the plug. Valves shall have weatherproof operators with mechanical position indicators and
a minimum bore size of 65 percent of nominal pipe size, unless the manufacturer can show an equivalent or greater
flow rate with a lower percentage of internal cross sectional area.
2.9.5.1 Valve Operation
Rotation of the handwheel toward open shall lift the plug without wiping the seals and retract the sealing slips
so that clearance is maintained between the sealing slips and the valve body. Rotation of the handwheel toward
closed shall lower the plug after the sealing slips are aligned with the valve body and force the sealing slips
against the valve body for positive closure. When valve is closed, the slips shall form a secondary fire-safe
metal-to-metal seat on both sides of the resilient seal.
2.9.5.2 Relief Valves
ANSI Class 150, steel body. Provide plug valves with automatic thermal relief valves to relieve the pressure
buildup in the internal body cavity when the plug valve is closed. Relief valves shall open at 25 psi differential
pressure, and discharge to the throat of and to the upstream side of the plug valve.
2.9.5.3 Bleed Valves
ANSI Class 150, steel body valve. Provide manually operated bleed valves that can be opened to verify that plug
valves are not leaking when in the closed position. Provide discharge piping so that released liquid can be
contained.
2.9.6 Level Alarm System
System shall be designed and installed in such a way that the system shall be continuously and automatically
self-checking without manual check. Electronic level sensors shall be thermistors or optic types, and be intrinsically
safe Class I, Division 1, Group D for hazardous environments, with recognized FM, CSA or UL approval. Both high
electronic level sensors shall be contained in a single multi-sensor holder/junction box. The sensor holder/junction
box shall be accessible from the tank top or stairway.
2.9.6.1 Electronic Level Alarms
Level alarms shall be mechanically and electrically independent and be totally isolated from the gauging system.
Two electronic high level alarms shall be provided for each tank. A High Level Alarm (HLA) shall be set at approximately
95 percent of the safe tank filling height and be arranged to actuate an audible alarm signal located at or near
the normal station of the person in control of the tank filling operation. A High High Level Alarm (HHLA) shall
be set at approximately 98 percent of the safe filling height. HHLA shall sound an audible and visual alarm
at a control panel and close the High Liquid Level Control Valve. In addition, an electronic low level alarm
shall actuate a visual and audible signal at the control panel when the tank is less than 5 percent filled.
2.9.6.2 Level Alarm Control Panel
Panel shall be located where indicated and contain one light and one relay output for each alarm point. An audible
alarm shall actuate whenever any alarm point has been reached. Panel shall further contain a green (Power ON)
status light and push button controls for alarm reset and test. Panel shall consist of a NEMA 4 style water-tight
housing for outdoor mounting locations. Panel shall operate with 115 VAC input power. Circuitry and cables
from the panel to the electronic level sensors in the tank shall be intrinsically safe.
2.9.7 High Liquid Level Control Valve
2.9.7.1 Valve
Valve shall be hydraulically operated, single-seated, normally closed,
diaphragm actuated, on/off type valve. Valve shall be field adjustable. Valve shall be provided with a position
indicator, float operator and assembly, pressure-operated pilot valves and accessories, solenoid-operated pilot
valve, and pressure gage quick-disconnect fittings located in the valve inlet, outlet, and cover. Valve shall
also operate with a special check valve feature and close rapidly when outlet pressure exceeds inlet pressure.
Service and adjustments shall be possible without removing the valve from the line. Portions of the valve coming
in contact with fuel shall be compatible with the fuel and be of corrosion-resistant material. Valve shall have
bodies, bonnets, and covers constructed of cast steel conforming to ASTM A 216/A 216M, Grade WCB internally plated
with chromium, nickel, or electroless nickel. Stem and trim shall be stainless steel. Valve shall be suitable
for a working pressure of 1900 kPa at 38 degrees C 275 psig at 100 degrees F with a weatherproof housing. Valve
packing shall be Viton in accordance with MIL-R-83248 or PTFE in accordance with MIL-P-24396. Valve shall be
provided with flanged end connections which are constructed of the same material as the valve body.
2.9.7.2 Float Operator and Assembly
Float operator and assembly shall be Grade CF3 (Type 304L) or Grade CF8M (Type 316) stainless steel conforming
to ASTM A 351/A 351M. Float operator shall be field adjustable. Float operator shall control the high liquid
level control valve based on the indicated actuation point. The float operator and assembly shall be mounted
to the storage tank's exterior where indicated. Means shall be provided to test the float operator's operation
and the control system's response.
2.9.7.3 Pressure-Operated Pilot Valves and Accessories
Valves shall be the adjustable, pressure-operated type and be adjustable in the field. Valves shall be tag identified
and be stainless steel conforming to ASTM A 351/A 351M, Grade CF3 (Type 304L) or Grade CF8M (Type 316) with stainless
steel internal working parts. A 40 mesh stainless steel screen, self-cleaning strainer shall be provided in
the pilot valve supply piping. Pilot system tubing shall be Type 316 stainless steel in accordance with ASTM A 269
. Control, supply, and return connections shall be provided with isolation valves. Tubing connections shall
be made with unions and not be welded or sealed with "O" rings.
2.9.7.4 Solenoid-Operated Pilot Valve
Valve shall be used for the electronic level alarm sensor control of the high liquid level control valve. Valve
shall be tag identified and be stainless steel conforming to ASTM A 351/A 351M, Grade CF3 (Type 304L) or Grade
CF8M (Type 316) with stainless steel internal working parts. Valve shall have a manual type operator or needle
valve for emergency manual bypass operation. Activation of this emergency manual bypass override, during filling
operations when no electrical power is available, shall cause a visible and audible indication of override status
at the Level Alarm Control Panel when electrical power is restored to the system. Solenoids shall operate on
120 volts, 60 Hz, single phase power and be housed in an UL labeled explosion-proof case for Class I, Division
1, Group D areas with maximum temperature rating of "T2D" 215 degrees C 419 degrees F.
2.9.7.5 Control Valve Operation
The high liquid level control valve shall fully close when either the float operator or the HHLA electronic level
alarm sensor are activated. Valve shall fully open when the tank's fuel is below the float operator's actuation
point and the HHLA electronic level alarm sensor is not activated. Means shall be provided to test the control
system's response at the activation point.
2.9.8 Thermometers
NOTE: Provide a plug for the second well if no remote temperature reading is
included in the project. Provide remote temperature reading capability if authorized
for the project, and delete requirement for threaded plug. Details of remote
temperature reading equipment should be included in separate (electrical) section
of the project specification.
NOTE: Insert appropriate Section number and title in blank below using format
per UFC 1-300-02.
Provide two thermometer wells designed as indicated not more than 457 mm 18 inches apart. In one well, provide
a 127 mm 5 inch non-mercury direct-drive Bourdon tube dial thermometer with one-degree divisions and a range
of minus 10 degrees C to plus 80 degrees C 0 degree F to plus 150 degrees F. Construct thermometer with stainless
steel case, bezel, fittings, and stem. Seal head against dust, fumes, and moisture. [Provide a threaded plug
for the second well.] [In the second well, provide a temperature-sensing bulb for remote reading temperature
system. Remote temperature reading system shall conform to [_____].]
2.9.9 Venting
NOTE: Use this text for vents on tanks without floating pans. Delete for tanks
with floating pans. Open vents will normally be used for storage of nonvolatile
products. Delete description of pressure/vacuum vents if open vents are used.
Pressure/vacuum vents may be used for kerosene type jet fuel tanks where especially
dirty environments exist. Delete description of open vents if pressure/vacuum
vents are used.
[Provide open vent at the center or at the highest elevation of the roof. Open vent shall have a weatherhood,
with galvanized steel bird screen with 6.0 mm 1/4 inch opening and a 3.43 mm 0.135 inch minimum wire diameter.]
[Breather (pressure/vacuum) vents shall have hinged or guided pallets. Moving or striking parts shall be of
nonferrous metal. Design shall be such that moisture cannot collect and freeze the pallet to its seat in cold
weather. Provide weatherhood, with galvanized steel bird screen with 6.0 mm 1/4 inch opening and a 3.43 mm 0.135
inch minimum wire diameter for vent openings. Size pressure and vacuum relief vents in accordance with API Std 2000
.]
2.9.10 Venting
NOTE: Use this text for vents on tanks with floating pans. Delete for tanks
without floating pans. Include API Std 650, Appendix G, for tanks with aluminum
dome roof.
2.9.10.1 Circulation Vents
Provide open circulation vents on the roof in accordance with API Std 650, Appendix H [and Appendix G]. Open
vents shall have a weatherhood, with corrosion-resistant steel bird screen with 6.3 mm 1/4 inch opening and 3.43
mm 0.135 inch minimum wire diameter.
2.9.10.2 Pressure-Vacuum Vents
Breather (pressure-vacuum) vents shall have hinged or guided pallets. Moving or striking parts shall be of nonferrous
metal. Design shall be such that moisture cannot collect and freeze the pallet to its seat in cold weather.
Size pressure and vacuum relief vents in accordance with API Std 2000.
2.9.11 Circumferential Stairway and Platform
OSHA 29 CFR 1910.24 and 29 CFR 1910.23. Support the stairway completely on the shell of the tank with ends of
the stringers clear of the ground, and at an angle of approximately 0.785 rad 45 degrees. Construct stairway
entirely of steel with treads of grating or an approved antislip floor plate. Railing shall be continuous around
the platform except for access openings. At access openings, any space wider than 150 mm 6 inches between the
tank and the platform shall be floored.
2.9.12 Ladders
OSHA 29 CFR 1910.27. Provide vertical interior ladders extending from the roof manholes to the tank bottom.
Provide exterior ladders or catwalks as required to gain access to the second roof manhole, which is on the opposite
side of the tank from the stairway platform. Provide drainage for horizontal surfaces such as stairs and floored
surfaces made from steel plates.
2.9.13 Roof Manholes
NOTE: Specify additional manholes or access holes when necessary to meet safety
requirements or local codes. Usually, larger diameter tanks (greater than 12
m 40 feet will require more manholes.
Provide [two] 610 mm 24 inch minimum square manholes for access to the interior of the tank through the roof.
Locate one manhole adjacent to the platform of the stairway on one end of a diameter of the tank. Locate a second
manhole at the opposite end of that diameter. [Provide other manholes as indicated.] Provide manholes with
safety handrails and located directly over the interior ladders. Provide hinged and weathertight manhole covers
with a formed fit.
2.9.14 Shell Access Holes
NOTE: Specify additional manholes or access holes when necessary to meet safety
requirements or local codes. Usually, larger diameter tanks (greater than 12
m 40 feet will require more manholes.
Provide two 750 mm 30 inch diameter access holes [and flush cleanout as indicated]. Locate the access holes
in the tank shell on opposite sides of the tank on a diameter approximately 1.57 rad 90 degrees from the roof
manholes and at a height convenient for personnel access into the tank. Provide access holes with welded steel
plate frames and covers. Secure the cover plates with corrosion-resistant bolts and nuts. Provide access holes
with gaskets and smooth gasket seats.
2.9.15 Fittings and Piping
Provide fittings and piping and other miscellaneous items as necessary to permit tank operations.
2.9.15.1 Product Inlet Connections
NOTE: Design shall include means to limit fuel inlet pipe velocity to less
than one meter per second 3 feet per second until fill pipe is completely submerged
to minimize potential for static electricity generation.
Product inlet connections shall consist of an external flange, a nozzle through the tank shell, supports, and
an internal expanding cone, as indicated. The flange shall be 1034 kPa 150 pound, conforming to ASME B16.5 with
slip-on or welded neck.
2.9.15.2 Product Outlet Connection
NOTE: Show piping details per DM-22 on drawings.
Product outlet connection shall consist of an external flange, a nozzle through the tank shell, internal flanges,
elbows, product withdrawal line assembly, and supports, as indicated.
2.9.15.3 Water Drawoff Connection
NOTE: For noncirculating tanks, provide a 25 mm one inch water drawoff connection
from a point 50 mm 2 inches above the bottom of the center sump and extend through
the tank shell to a filter/separator, waste tank or oil/water separator. Show
piping on drawings.
Water drawoff connection shall consist of an external flange or coupling, nozzle and 25 mm one inch pipe through
the tank shell, supports, and fittings to a point 50 mm 2 inches above the bottom of the center sump, as indicated.
Provide a hand-operated drain pump with a maximum discharge of 0.63 to 1.26 liters per second 10 to 20 gpm on
the water drawoff line.
2.9.16 Scaffold Cable Support
Provide scaffold cable support on the tank roof in accordance with API Std 650. Locate the support near the
center of the tank and in a manner that supported cables will have maximum range and flexibility of operation
with minimum interference with other tank fittings.
2.9.17 Tracer Gas Detection System
NOTE: The tracer gas test is optional and is not shown on any of the standard
drawings. If the test is desired, include any necessary detail drawings. Include
only if specifically listed in the scope of work.
2.9.17.1 System
A tracer gas vapor collection/distribution system shall be installed in the sand below the tank bottom prior
to tank construction. This shall include 20 mm 3/4 inch PVC pipe laid horizontally under the tank bottom. Pipe
shall be at least 230 mm 9 inches below the tank bottom in the sand to avoid damage during welding of the tank
bottom. The number of probes shall be as indicated on the drawings and be determined by locating 6100 mm 20
foot diameter circles on the tank bottom beginning at the center of the tank. Each of these circles represents
the influence of one probe. Circles shall overlap so that all areas of the tank bottom are covered. Probes
shall be of sufficient length to extend from the center of each circle of influence to a termination point at
the exterior of the ring wall.
2.9.17.2 Exterior Termination Points
Exterior termination points shall be 20 mm 3/4 inch female pipe threads with a 20 mm 3/4 inch plug located at
the exterior of the concrete ring wall. The probe shall be connected to the coupling using a threaded adapter.
2.9.17.3 Interior Termination Points
Interior termination points (under tank bottom) shall be covered with a material designed to deter soil erosion
while allowing air and water to move in and out of the open probe end. This material shall not be affected by
hydrocarbons and shall be corrosion protected.
2.9.18 Aluminum Dome Roof
Provide aluminum dome roof for the [existing] tank in accordance with API Std 650, Appendix G, "Structurally
Supported Aluminum Dome Roofs," and as indicated and specified. The dome fabricator/erector shall furnish all
labor, materials and equipment required to design, fabricate, deliver, and erect the aluminum dome structure.
2.9.19 Material for Dome Roof
a. Triangulated space truss: 6061-T6 aluminum struts and gussets
b. Triangular closure panels: 16 gage 3003-H16 aluminum sheet
c. Triangular skylight panels: (Not required)
d. Tension ring: 6061-T6 aluminum
e. Fasteners: 7075-T73 aluminum or series 300 stainless steel
f. Support bearing pads if required: Teflon faced neoprene
g. Anchor bolt: 300 series stainless steel
h. Dormers, doors, vents, and hatches shall be 6061-T6, 5086-H34 or 3003-H16 aluminum
i. Sealant: Heat resistant polysulfide.
2.9.19.1 Roof Design Loads
Design loads shall be specified or indicated. The dead weight of the dome structure shall not exceed 17 kilograms
per square meter 3.5 pounds per square foot of surface area.
2.10 FLEXIBLE MEMBRANE LINER (FML)
NOTE: The products listed below are considered to meet this specification as
of December 1991.
Petroguard 10 sold by MPC Containment Systems, Ltd., 4834 South Oakley, Chicago
IL 60609, POC Ed Reicin, 800-621-0146, 312-927-4120.
L3284NESU made by Cooley, Inc., 50 Esten Ave, Pawtucket, RI 02860, POC Steve
Seiner, 800-333-3048, 401-724-9000.
Style 1642 PTF MS-400 made by Seaman Corporation, 216-262-1111, 800-321-2615,
1000 Venture Blvd., Wooster Ohio 44691, POC Felon Wilson Knoxsville, TN 615-691-9476.
The FML shall demonstrate the acceptable limits of the properties listed under Table 1. The FML shall be factory
produced from a base fabric that is completely covered with a polymer. The base fabric shall weigh no less than
440 grams per square meter 13 ounces per square yard and be made of aramid (kevlar), polyester, or nylon. The
FML shall have an overall finished weight no less than 1017 grams per square meter 30 ounces per square yard.
Factory seams shall be made with a 50 mm 2 inch overlap plus or minus 6 mm 1/4 inch by an automatic thermal high-pressure
welding process. The FML shall retard the growth of mildew and be capable of containing the liquid stored, withstanding
temperatures up to 82 degrees C 180 degrees F, withstanding humidity up to 99 percent relative humidity, and
withstanding direct exposure to sunlight.
2.10.1 Job Lot of FML
A job lot of FML is defined by this specification as the amount of FML product that can be produced from a singular
mixture of chemicals. Any FML material created from a new or altered mixture of chemicals shall be considered
a new job lot.
2.10.2 FML Samples
Twenty four samples shall be cut from every job lot of FML. Each sample shall be approximately 216 by 280 mm
8 1/2 by 11 inches in size. Eight of the samples shall be cut across factory seams.
2.10.3 FML Factory Test
Each manufacturer's job lot of FML shall have each of the FML properties verified by the factory test procedures
and methods listed below. No substitute methods shall be allowed for verification of any property. Each separate
verification of a property shall be made on a separate sample. The FML shall demonstrate through factory testing
the acceptable limits of the following properties listed in Table 1. The properties shall be verified by each
of the test standards listed.
TABLE 1. Standards and Limits for FML Properties (Metric)
Acceptable Test
Property Limits Standard Notes
Minimum Overall
Finished Thickness 0.81 mm ASTM D 751
Minimum Tear 178 N ASTM D 751
Strength (ibd) Tongue Method (Warp & Fill)
Minimum Adhesion 89 N ASTM D 751
Strength per 25 mm
Minimum FML 4448 N ASTM D 751
(MTS) (ibd) Grab Method (Warp & Fill)
Minimum FML 2670 N ASTM D 751
(MTS) (ibd) Cut Strip Method (Warp & Fill)
Minimum FML Seam ASTM D 751
Shear Strength See Note 1 Section 53
Minimum Abrasion
Resistance 5000 cycles ASTM D 3389 See Note 2
Minimum Withstanding of
Accelerated Weathering 1000 hours ASTM D 2565 See Note 3
Minimum Bursting ASTM D 751
Strength 10 343 kPa Ball Tip Method
Maximum 206 850 kPa
Stiffness (ibd) ASTM D 747
Hydrostatic 3448 kPa ASTM D 751
Resistance
Maximum 30.5 grams per square ASTM E 96/E 96M
Permeability meter per 24 hours Procedure BW See Note 4
Fuel No Delamination, No
Compatibility Bubbles, No Discoloration See Note 5
Maximum Volume 15 percent of
Swell (Coating original See Note 6
Compound Only)
Maximum Weight 10 percent of
Gain or Loss original See Note 5
TABLE 1. Standards and Limits for FML Properties
Acceptable Test
Property Limits Standard Notes
Minimum Overall
Finished Thickness 32 mils ASTM D 751
Minimum Tear 40 pounds ASTM D 751
Strength (ibd) Tongue Method (Warp & Fill)
Minimum Adhesion 20 pounds ASTM D 751
Strength per inch
Minimum FML 1000 pounds ASTM D 751
(MTS) (ibd) Grab Method (Warp & Fill)
Minimum FML 600 pounds ASTM D 751
(MTS) (ibd) Cut Strip Method (Warp & Fill)
Minimum FML Seam ASTM D 751
Shear Strength See Note 1 Section 53
Minimum Abrasion
Resistance 5,000 cycles ASTM D 3389 See Note 2
Minimum Withstanding of
Accelerated Weathering 1,000 hours ASTM D 2565 See Note 3
Minimum Bursting ASTM D 751
Strength 1,500 pounds Ball Tip Method
Maximum 30,000 pounds
Stiffness (ibd) ASTM D 747
Hydrostatic 500 pounds per ASTM D 751
Resistance square inch
Maximum 0.10 ounces per square ASTM E 96/E 96M
Permeability foot per 24 hours Procedure BW See Note 4
Fuel No Delamination, No
Compatibility Bubbles, No Discoloration See Note 5
Maximum Volume 15 percent of
Swell (Coating original See Note 6
Compound Only)
Maximum Weight 10 percent of
Gain or Loss original See Note 5
Table Abbreviations:
(ibd) in both direction
(MTS) Material Tensile Strength
Notes:
1. The acceptable limit for the seam shear strength shall be 95 percent of the minimum (MTS) property using
the Strip Method.
2. Test until fabric exposure with a H-22 wheel loaded to 1,000 grams.
3. Manufacturer's certification of the FML, instead of actual factory testing, may be considered acceptable
for the Minimum Withstanding of Accelerated Weathering if the certification verifies that the acceptable limits
listed were previously achieved using the test standard listed. Data from either a manufacturer's certification
or an actual factory test shall verify that no visible cracking or appreciable changes resulted as a result of
the testing.
4. The test shall be performed using the Inverted Water Method with ASTM Fuel B.
5. Testing shall be performed in accordance with ASTM D 543 by immersion in ASTM Fuel B for 14 continuous
days at room temperature.
6. Testing shall be performed in accordance with ASTM D 471.
2.10.4 FML Ring Wall Sealant
The FML ring wall sealant shall be compatible with the FML, concrete, and the fuel being stored.
2.10.5 FML Components
Components such as sleeves, boots, etc., shall be factory prefabricated from the FML material and have the same
fabrication characteristics.
2.10.6 Fuels for Testing FML
Materials, other than the FML, shall be resistant to the fuel or fuels being stored. Fuels as required or mentioned
by this specification shall be in accordance with the following:
2.10.6.1 Motor Gasoline (Mogas)
Mogas shall be in accordance with ASTM D 4814.
2.10.6.2 Diesel
Diesel shall be in accordance with FS A-A-52557.
2.10.6.3 No. 2 and No. 4 Fuel Oils
Oils shall be in accordance with ASTM D 396.
2.10.6.4 JP-4 and JP-5
Fuels shall be in accordance with MIL-DTL-5624.
2.10.6.5 JP-7
Fuel shall be in accordance with MIL-DTL-38219.
2.10.6.6 JP-8
Fuel shall be in accordance with MIL-DTL-83133.
2.10.6.7 ASTM Fuel B
ASTM Fuel B as referenced in this section shall be in accordance with ASTM D 471.
2.11 ANTISEIZE COMPOUND
Provide antiseize compound for fasteners on tank exterior flanges and bolted connections and covers. Provide
MIL-PRF-907 compound on steel fasteners. Provide an approved antiseize compound for stainless steel fasteners.
Do not use MIL-PRF-907 compound on stainless steel. On tank interior fasteners, use oil only.
2.12 SAND CUSHION
Cushion shall be located on top of the flexible membrane liner (FML) and beneath the tank bottom plates. Cushion
shall be a minimum of 8 inches thick and be fine sand aggregate in accordance with ASTM C 33. Cushion shall
contain no more than 25 parts per million (ppm) chlorides, no more than 30 ppm sulfates, and have a pH greater
than 7. Magnesium sulfate shall be used in the ASTM C 88 soundness test.
PART 3 EXECUTION
3.1 SAFETY PRECAUTIONS
API RP 2009 for fire and explosion hazard areas.
3.2 CONSTRUCTION
3.2.1 Tank
NOTE: Provide a reinforced concrete ring wall for all tanks, regardless of
size, as shown in Figure 4 of DM-22.
Provide tank of welded construction, and support tank on a concrete ring wall. Slope the tank bottom down to
the center sump approximately 150 mm 6 inches for each 3.00 m 10 feet of tank radius. Butt-weld or lap-weld
bottom plates with the outer plates on top. Slope the roof down from the center to the periphery. Reinforce
openings larger than 50 mm 2 inches in diameter through plating of the tank shell and roof. Provide structural
stiffening, consisting of rings, thicker plates, or other approved means to maintain roundness when the tank
is subjected to wind or seismic loads.
3.2.1.1 Prohibition of Protective Coatings on Surfaces to be Welded
Remove protective coatings on surfaces to be welded and on surfaces not less than 25 mm one inch from weld preparation.
"Weld-through" inorganic zinc coatings and similar coatings will not be permitted.
3.2.1.2 Welding of Column Base
When columns are provided in the tank, weld the column base to the tank bottom. Welds shall be continuous and
shall provide a seal against the entry of water or other liquids into the space between the column base and the
tank bottom.
3.2.2 Area Beneath Tank
Cover the area beneath the tank with a fuel resistant plastic membrane of FML in accordance with paragraph entitled
"Installation of FML."
Lay the plastic over a thoroughly compacted select subgrade free from rocks that could puncture the plastic.
Provide a minimum 100 mm 4 inchesof compacted clean sand or similar material over the plastic. Securely attach
and cement the plastic membrane to the inside of the concrete foundation ring wall beneath the tank shell. Provide
a drain pipe or pipes through the concrete foundation ring wall so that water beneath the tank can escape by
gravity. The drain pipe shall also serve as a telltale for tank bottom leaks. Provide FML between the tank
and berm where indicated.
3.2.3 Mastic Seal
Seal the outer edge of the joint between the concrete tank foundation ring and the tank floor plate by caulking
with mastic seal.
3.2.4 Nozzles
Nozzles less than 50 mm 2 inches in size shall be flanged or screwed type. Sizes 50 mm 2 inches in size or larger
shall be flanged and shall have reinforcing plate. Nozzles for pipe connections inside the tank shall be flanged
inside and outside of tank. Reinforcing plates for shell nozzles shall be rolled to the curvature of the shell.
3.2.5 Drain Sump
NOTE: For sites where gravity draining of water is not possible or practical,
the project specification should include a drain pump for the stripping line
to the sump. Such a pump should be hand-operated, with a maximum discharge
of 0.63 to 1.26 liters per second 10 to 20 gpm, to avoid vortexing the stored
product and drawing it down the drain line. Show design details on project drawings.
Weld drain sump to the lowest point of the tank bottom. Construct drain sump of extra strong steel buttwelding
pipe cap installed below the tank bottom, and provide with a stripping line as indicated.
3.2.6 Installation of Level Controls
Install level alarm system and high liquid level control valve in accordance with the manufacturers' instructions.
Bleed air from control valve pilot system tubing in accordance with the manufacturer's written instructions.
Valve will malfunction with air in the tubing.
3.2.7 Fire Protection
NOTE: Provide a foam extinguishing system for tanks of 378,500 or more liters
100,000 or more gallons capacity per DM-22. Consult the Fire Protection Branch
at the appropriate EFD for guidance. Delete paragraph if not applicable.
Provide foam extinguishing system in accordance with Section 21 13 21.00 20 FOAM FIRE EXTINGUISHING FOR FUEL
TANK PROTECTION.
3.2.8 Cathodic Protection
NOTE: Provide cathodic protection if required to comply with local regulations.
Delete paragraph if not applicable.
NOTE: Insert appropriate Section number and title in blank below using format
per UFC 1-300-02.
Provide cathodic protection in accordance with [_____].
3.3 INSTALLATION OF FML
3.3.1 Field Engineer
The field engineer shall supervise the complete installation of the FML and perform each FML inspection and test.
3.3.2 Preparation
Prior to laying out the FML, three sample field seams shall be performed. Each seam shall be 1500 mm 5 feet
in length. Seams shall be made only when the ambient temperature and the temperature of the FML are both minus
4 degrees C 25 degrees F or higher.
3.3.3 Surface Preparation
The surfaces to be covered shall be free of vegetation, rocks, debris, etc., graded true, compacted, and be smooth
with no abrupt projections of any kind.
3.3.3.1 Surface Finishing
Finish tank interior surfaces in accordance with Section 4 of NACE SP0178, and accompaning Visual Comparator,
to the condition described and shown for NACE Weld Designation "C" welds. Finish tank enterior surfaces in accordance
with Section 4 of NACE SP0178, and accompanying Visual Comparator, to condition described and shown for NACE
Weld Designation "D" welds.
3.3.4 FML Layout and Installation
After successful completion of the FML visual inspection, the FML shall be laid out. Laying out and welding
FML shall only be done when the ambient temperature and the temperature of the FML are both minus 4 degrees C
25 degrees F or higher. Field seams shall have a 50 mm 2 inchoverlap plus or minus 6 mm 1/4 inch, and be made
by the FML manufacturer's authorized representative. Panels or sheets of FML to be seam welded together shall
be laid out prior to welding field seams. The overlapped areas shall be cleaned and prepared according to the
installation instructions and procedures. Welds shall be tightly bonded.
3.4 FIELD QUALITY CONTROL
NOTE: Availability of utilities services and charges are established by the
station and should be stated in Division 1 of the contract specifications. Use
alternate test methods for testing shell if water supply is inadequate for filling
the tank.
The Contracting Officer will conduct field inspections and witness field tests and trial operations specified
in this section. The Contractor shall perform all trial operations and field tests and provide all labor, equipment
and incidentals required for testing. The Government will provide water required for field tests, when available.
3.4.1 FML Tests
3.4.2 FML Vacuum Box Test
After successful completion of the FML visual inspection, a vacuum box test shall be performed on all field seams,
the area around the seams, and all FML surfaces showing injury due to scuffing, penetration by foreign objects,
or distress from rough subgrade. A glass topped vacuum box which has a neoprene sealing gasket shall be used.
The vacuum box test shall be performed as follows:
a. A commercial bubble forming solution shall be applied to the area to be tested.
b. The vacuum box shall be positioned over the area and a vacuum slowly applied until a differential
pressure of 7 kPa one psi is achieved and held for at least 5 seconds while observing the solution
for bubble formation.
c. If the vacuum box test indicates a continuous stream of bubbles on repeated testing at the
same location, then the area being tested shall be considered damaged and shall be repaired
and retested.
d. If the vacuum box test do not indicate a leak, then the vacuum shall be slowly increased
until a maximum differential pressure of 14 kPa plus 0.0 or minus 2 kPa 2 plus 0.0 or minus
0.25 psi is achieved and held for at least 20 seconds. If the test indicates a continuous stream
of bubbles on repeated testing at the same location, then the area being tested shall be considered
damaged and shall be repaired and retested. Care must be taken to limit the vacuum to no more
than the maximum differential pressure because, if it is exceeded by more than 2 kPa 0.25 psi
the FML shall be considered damaged and shall be replaced and retested.
3.4.2.1 FML Air Lance Tests
After successful completion of the FML vacuum box test, an air lance test shall be performed on all seams not
accessible with a vacuum box test (i.e. small seams around penetrations, oddball types of patches, etc.). The
air lance test will be performed using a 345 kPa 50 psig jet of air regulated and directed through a 5 mm 3/16
inch diameter nozzle, applied to the upper edge of an overlapped seam or repaired area to detect an unbonded
area. Inflation of any section of the seam by the impinging air stream shall be indicative of an unbonded area.
Unbonded areas shall be repaired and retested.
3.4.3 FML Inspections
3.4.3.1 Sample Field Seam Inspection
a. Visual Inspection - Sample field seams shall be subjected to a visual inspection performed
within 30 hours after the seam has been made, cured, and cooled.
b. Vacuum Box Inspection - After successful completion of the visual inspection, a vacuum box
inspection shall be performed. A glass topped vacuum box which has a neoprene sealing gasket
shall be used. The vacuum box test shall be performed as follows:
(1) A commercial bubble forming solution shall be applied to the area to be tested.
(2) The vacuum box shall be positioned over the area and a vacuum slowly applied until a differential
pressure of 7 kPa one psi is achieved and held for at least 5 seconds while observing the solution
for bubble formation.
(3) If the vacuum box test indicates a continuous stream of bubbles on repeated testing at
the same location, then the area being tested shall be considered damaged and shall be repaired
and retested.
(4) If the vacuum box test do not indicate a leak, then the vacuum shall be slowly increased
until a maximum differential pressure of 14 kPa plus 0.0 or minus 2 kPa 2 plus 0.0 or minus
0.25 psi is achieved and held for at least 20 seconds. If the test indicates a continuous stream
of bubbles on repeated testing at the same location, then the area being tested shall be considered
damaged and shall be repaired and retested. Care must be taken to limit the vacuum to no more
than the maximum differential pressure because, if it is exceeded by more than 2 kPa 0.25 psi
the FML shall be considered damaged and shall be replaced and retested.
3.4.3.2 FML Initial Inspection
A visual inspection of the FML shall be performed on each FML panel or sheet as it is unrolled. The Contracting
Officer shall be notified of any visually detected damage. The visual inspection shall also verify the finished
surface to be covered with the FML is properly graded and compacted.
3.4.3.3 FML Seam Inspection
Field seams shall be subjected to a visual inspection performed within 30 hours after the seam has been made,
cured, and cooled. Any seams visually found to be defective shall be repaired and reinspected.
3.4.3.4 Acceptance Inspection
As soon as practicable after successful completion of the FML vacuum box test and the air lance tests, an acceptance
inspection shall be performed. If the inspection reveals any defects in the work, such defects shall be repaired
or the unsatisfactory work replaced before acceptance. The cost of such repairs and replacements shall be borne
by the Contractor. The Contractor shall provide materials, facilities, and equipment necessary to permit adequate
inspection by the Contracting Officer or his representative.
3.4.4 Manufacturers Field Service
If any problems are noticed in any inspection of a seam, the Contracting Officer shall be notified immediately.
The FML manufacturer's point of contact shall also be contacted by telephone and informed that the installation
of their product can not be adequately completed. After a solution has been formed, jointly between the FML
manufacturer and their authorized representative, as to why the problems were encountered, another set of sample
field seams shall be made and reinspected.
3.4.5 Sand Cushion Tests
Test the sand prior to installing any storage tank bottom to verify the amount of chlorides (ppm) and sulfates
(ppm) and to determine the pH value of the sand. Test result shall conform to paragraph entitled "Sand Cushion."
3.4.6 Tank Calibration
NOTE: Delete paragraph if it is in the best interest of the Government to enter
into a separate contract for tank calibration. If the paragraph is used, the
method of calibration and gage tables required for "critical measurement" should
be specified if tank will be used for the custody transfer of petroleum products.
Method of calibration and gage tables required for "operating control" should
be specified if tank will be used for other than custody transfer of products.
After installation of the tank is complete, prepare a calibration table for the tank showing the volume of fuel
in barrels of 158.76 liters 42 gallons in the tank to any height of liquid in m feet, inches, and mm eighths
of an inch when measured by a steel tape lowered through the roof. Calibrate the tank in accordance with[ API MPMS 2.2A
][ API MPMS 2.2B] for [critical measurement] [operating control]. Correct the data obtained for use with the
product to be stored.
3.4.7 Weld Inspection
Perform inspection of welds in accordance with API Std 650. Inspect butt welds requiring complete penetration
and complete fusion by the radiographic method.
3.4.8 Tightness Tests and Welding Repairs
NOTE: Availability of utilities services and charges are established by the
activity and should be stated in Division 1 of the contract specifications.
Use alternate test methods for testing shell if water supply is inadequate for
filling the tank.
Perform tightness tests and repairs in accordance with API Std 650, except as modified herein, prior to blast
cleaning and application of the protective coating.
3.4.8.1 Test of Tank Bottom
Test tank bottom immediately after completion and prior to installing any columns. Test seams in bottom of tank
by applying a commercial soap film and subjecting the seam to a vacuum. Use a glass top vacuum box with hypalon
or neoprene sealing gasket. Apply a commercial bubble forming solution to the weld or area to be tested; position
the vacuum box over the area and slowly pull a partial vacuum. Observe the solution film for bubble formation
between 0-14 kPa 0-2 psi differential pressure. Continue to open the valve until a differential pressure of
34.5 kPa 5 psi or 3.50 m 11.5 feet of water or 259 mm 10.2 inches of mercury is achieved and hold for at least
20 seconds while continuing to observe the solution for bubbles.
3.4.8.2 Tank Shell to Bottom Inside Corner Welds
Inspect tank shell to bottom inside corner welds using the oil test. After the inside fillet weld is made, apply
oil to the outside corner crevice before the outside weld is made. After 4 hours, inspect the inside fillet
weld for oil penetration through defects, and correct defects.Remove oil completely prior to finishing weld joint.
Then complete the remainder shell to bottom weld joint.
3.4.8.3 Tank Shell
Test the shell by filling tank with water and maintaining it full for a period of not less than 24 hours, then
inspect shell for leaks. The appearance of damp spots shall be considered evidence of leakage. Minimize water
retention time to limit rusting of tank interior. If water supply is insufficient for filling tank, perform
alternate testing of shell in accordance with API Std 650. Repair leaks disclosed by the tests by drilling,
chipping, or gas gouging and rewelding, or by other methods, then retest the tank and prove the tank tight.
3.4.8.4 Stripping Line
Test stripping line from sump, product inlet line, and product outlet line with water at 345 kPa 50 psi.
3.4.8.5 Tracer Gas Test
Note: If the "Tracer Gas Detection System" paragraphs in Part 2 were deleted,
then delete the following paragraphs.
The tracer gas test shall be performed preceding the vacuum box test and be in accordance with the following:
a. The test shall be conducted using an analytical method which can detect vapor movement through
any void in the tank bottom.
b. The testing company shall locate the leaks to within 75 mm 3 inches of actual leak location
by attempting to force or draw a detectable gas through the tank bottom.
c. The gas used shall be an non-explosive, non-toxic, and shall not be damaging to the ozone
layer.
d. The instrumentation shall be able to detect the leak as being used at the accuracy described
below.
e. The test shall be conducted before application of any coating.
f. A leak is characterized by the detection of 1 tenth (0.10) part per billion in air of the
detectable gas on the opposite side from its point of injection.
g. The tracer gas will be introduced to the underside of the tank using the monitoring well
leak system piping. Gas release shall be pressure-regulated to prevent uplift and damage to
the tank bottom.
3.4.9 Floating Pan Tests
NOTE: Delete paragraph if floating pan is not used.
Following the installation of a floating pan, the deck penetrations and rim area shall be subjected to a visual
inspection for seal tightness.Leaks or seal deformations shall be corrected according to manufacturer's recommendations.
Following the seal inspection, the floating pan shall be subjected to a flotation test. The tank shall be filled
with to 25 percent of the total capacity with fuel. While filling the tank, the top of the floating pan shall
be visually inspected for fuel leakage. The appearance of damp spots on the top of the floating pan shall be
considered evidence of leakage, the Contracting Officer shall be notified and the fuel removed immediately.
Leaks shall be repaired and the flotation test performed again.
3.4.10 Fill Test
If the tightness test and welding repairs above are completed without a hydrostatic test of the tank using water,
fill test the tank using fuel. Tank piping and appurtenances shall be ready for service. The Government will
provide the necessary fuel and labor to fill the tank with fuel. Advise the Contracting Officer, in writing,
at least 10 days in advance of the need for this service. Fill tank half full and check that drain valves are
closed and check tank for leaks. Keep tank half full the first 12 hours of test, then fill tank to full capacity
and check that drain valves are closed and check tank for leaks. Monitor tank level hourly during the first
24 hours of the fill test and notify the Contracting Officer immediately of any leaks detected. Padlock drain
valves closed for the duration of the test and provide one set of keys to the Contracting Officer. After the
temperature of the fuel has become stabilized, take daily readings of the fuel level for a period of 10 days.
If there is no measurable drop in the fuel level during this period, the tank will be accepted. If leakage becomes
apparent during the filling or the test period, immediately notify the Contracting Officer and Government personnel
will pump the fuel from the tank. Free the tank of vapor, clean it, and then carefully inspect the tank for
evidence of failures at the Contractor's expense. Repair defects found and repeat fill tests.
3.4.11 Testing High Level Controls
3.4.11.1 Tank High Level Alarm
After flushing is completed, the Government will furnish fuel to fill the tank. Check the operation of the high
level and high level alarms. Verify operation of the alarm horn and light.
3.4.11.2 Tank High Level Shutoff Valve
Check the operation of the high level shutoff valve on the inlet to the tank to assure that the valve closes
fully at high tank level. Check closing by the float valve and the solenoid pilot valve separately. Before
the tank high level is reached, verify operation of the valve by the manual operation of the float and solenoid
pilot. Check for proper operation when the tank is filled with appropriate safety measures.
3.4.12 Retesting
Deficiencies found shall be rectified and work effected by such deficiencies shall be completely retested at
the Contractor's expense.