Qualifications and Maintenance of Tank Cars and Ton Containers

9.1 Scope

The requirements specified in this section apply to any person who qualifies, modifies, marks, handles, or maintains tank cars or ton containers in Canadian service.

9.2 General Requirements

9.2.1 Tank Cars

A tank car facility or person performing a function on a tank car must comply with the requirements of the owner concerning qualification and maintenance and the applicable requirements of this standard and of the AAR Specifications for Tank Cars publication. In case of conflict, the requirements of this standard apply.

9.3 Tank Car Qualification

Unless otherwise specified in this section and for the purpose of tank car qualification, column 2 of the following table indicates the inspections and tests that are required for the corresponding qualification item of column 1.

Qualification Table

Qualification Items Inspections and Tests
Tank car Visual inspection
Structural integrity inspection
Safety systems inspection
Thickness Thickness test
Service equipment Service equipment inspection
Leak testing
Lining or coating Lining or coating inspection
Stub sills Stub sill inspection

9.4 Requirements for Qualification and Maintenance of Tank Car of Stub Sills

9.4.1 Inspections

All tank cars of stub sill design must receive inspections of the stub sills by a tank car facility at the time of manufacture and periodically thereafter to ensure structural integrity of the sills, using inspection procedures specified in clause 9.4.3.

9.4.2 Intervals

The inspection interval must not exceed 10 years, nor the interval established for the tank structural integrity inspection. Inspections must be performed at shorter intervals when a reliability assessment of a stub sill design indicates a tendency to rapidly develop rejectable defects.

9.4.3 Inspection procedures and records

9.4.3.1 The inspections must include all weld attachments of stub sill-to-pad, stub sill-to-head brace (if used), bolster-to-sill, and head brace-to-pad. Inspections must be made both inboard and outboard of the body bolster.

9.4.3.2 The inspections must include the surfaces of the sill top flange, sill webs, sill bottom flanges and sill pads in the vicinity of the attachment welds referred to in clause 9.4.3.1 for the presence of parent metal cracks and fractures or other significant damage both inboard and outboard of the body bolsters.

9.4.3.3 Inspection personnel, procedures and techniques for attachment welds must conform to Appendix T of the AAR Specifications for Tank Cars publication.

9.4.3.4 Appropriate inspection ports must be provided in jackets and head shields and other equipment removed, such as draft gear as required to provide sufficient access for adequate inspections. Welds and other surfaces as required must be cleaned and made accessible consistent with the inspection method and technique requirements.

9.4.3.5 The year in which a stub sill inspection is performed and the inspection due date must be applied in the location specified on the qualification stencil (Fig. C5 or Fig. C9 of the AAR Specifications for Tank Cars publication) in numerals at least 25.4 mm (1 in.) in height. A code indicating the tank car facility having performed the inspection must also be applied.

9.4.3.6 Results of inspections must be documented and kept by the tank car owner throughout the period of ownership of the tank car plus one year after a change of ownership. The inspection results must include all the information included in form SS3: "Report of Tank Car Stub Sill Inspection" or other reporting approved by the Committee, referred to in Appendix Y of the AAR Specifications for Tank Cars publication.

9.4.4 Maintenance, Modification and Repairs

Repairs to parent metal cracks in stub sill structural components or attachment welds referred to in clause 9.4.3.1 must be performed in accordance with AWS D15.1. Repairs must be performed in accordance with the tank car owner's documentation and procedures.

9.5 Requirements for Qualification of Tank Cars

9.5.1 Owner's Responsibilities, General

An owner of a tank car, a lining or coating or of service equipment is responsible for:

  1. qualifying the tank car including stub sills, the lining or coating, or the service equipment in conformance with the requirements set out in this section;
  2. scheduling and the performance of inspections and tests of the tank car including stub sills, the lining or coating, or the service equipment;
  3. developing, implementing, and evaluating a qualification program for the tank car including stub sills, the lining or coating, or the service equipment;
  4. validating and specifying the methods and procedures for the non-destructive examination of the tank car including stub sills, the lining or coating, or the service equipment. Such methods and procedures must be adequate to detect defects and conditions that could compromise the reliability of the tank car, the lining or coating, or the service equipment; and
  5. developing the documentation relative to the requirements set out in this section.

9.5.2 Owner's Responsibilities Regarding Tank Car Facilities

An owner of a tank car, lining or coating, or service equipment is responsible for ensuring that each tank car facility complies with the owner's qualification program developed in accordance with the requirements of this section, through periodic analysis and surveillance of the qualification activities of the tank car facility, including:

  1. inspection and testing of the tank car including stub sills, the lining or coating, or the service equipment in accordance with the requirements set out in clause 9.5;
  2. evaluating the results of inspections and tests in accordance with the requirements related to qualification set out in clause 9.6;
  3. marking of the tank car in accordance with the requirements set out in clause 7.4; and
  4. preparing of the documentation in accordance with the requirements set out in clause 9.8.

9.5.3 Responsibilities of Tank Car Facility

A tank car facility must obtain the permission of the equipment owner before performing work affecting modification, repair, or qualification of the owner's equipment. For the purposes of qualification and maintenance, the tank car facility must use the written instructions furnished by the owner or have written confirmation from the owner allowing the use of written instructions furnished by the owner or have written confirmation from the owner allowing the use of written instructions furnished by another. A tank car facility must report all work performed to the owner. The tank car facility must also report observed damage, deterioration, failed components, or non-compliant parts to the owner.

9.5.4 Qualification of Tank Cars

9.5.4.1 The maximum interval for inspection and tests shall not exceed the requirements set out in column 2 of the following table for each corresponding inspection and test set out in column 1, except where an adjustment is required in clauses 9.5.13.1 and 9.5.13.2.

Frequency of Inspections and Tests

Inspections and Tests Maximum Interval (years) Reference
Visual inspection 10 Clause 9.5.6
Structural integrity inspection 10 Clause 9.5.7
Thickness test 10 Clauses 9.5.8 and 9.5.9
Safety systems inspection 10 Clause 9.5.10
Lining or coating inspection, for lining or coating applied for the protection of the tank as per clause 9.5.11 Clause 9.5.11
Service equipment inspection 10 Clause 9.5.12
Stub sill inspection 10 Clause 9.6

9.5.4.2 A riveted tank car tank or the inner container of a Specification 115 tank car must have a hydrostatic tank test conforming to the applicable requirements set out in clause 8.4.20 of this standard and par. D4.2 of the AAR Specifications for Tank Cars publication at a maximum interval of ten years. The hydrostatic test pressure must be equal to or greater than the specification test pressure of the tank car tank.

9.5.4.3 For a tank car designed for cryogenic liquids, including a Specification 113 or AAR 204W tank car, only the following minimum inspections and tests and maximum intervals apply:

  1. a visual inspection of the exterior surface of the outer shell in conformance with the requirements set out in clauses 9.2.1 and 9.5.6 a., at a maximum interval of ten years;
  2. a visual inspection in conformance with the requirements set out in clauses 9.2.1 and 9.5.6 c., d., e., f., and h. at a maximum interval of ten years;
  3. a structural integrity inspection in conformance with the requirements set out in clauses 9.2.1 and 9.5.7.1 at all locations susceptible to damage that could compromise the reliability of the tank car, at a maximum interval of ten years. At a minimum, the inspection must include:
    1. all outer shell transverse fillet welds with dimensions greater than 6 mm (¼ in.) within 122 cm (4 ft.) of the bottom longitudinal centerline, except body bolster pad attachment welds;
    2. the termination of longitudinal fillet welds with dimensions greater than 6 mm (¼ in.) within 122 cm (4 ft.) of the bottom longitudinal centerline on the outer shell; and
    3. the non-reinforced exposed outer shell butt welds within 61 cm (2 ft.) of the bottom longitudinal centerline.
  4. d. a service equipment inspection in conformance with the requirements set out in clauses 9.2.1 and 9.5.12 at a maximum interval of ten years, except that the maximum interval for pressure-relief valves on specification 113 tank cars is five years;
  5. e. a stub sill inspection in conformance with the requirements set out in clauses 9.2.1 and 9.4 at a maximum interval of 10 years.

9.5.4.4 All qualification requirements need not be performed at the same time.

9.5.4.5 Pressure relief devices on tank cars used in the handling, offering for transport or transporting of anhydrous ammonia must be qualified at an interval not exceeding five years. Non-coated carbon steel springs must be replaced with a stainless steel spring or a spring coated to protect against ammonia stress corrosion cracking, at the time of qualification.

9.5.5 Other Conditions Requiring Inspections and Tests

Before a tank car is used in the handling, offering for transport, or transporting of dangerous goods and despite the maximum intervals for qualification set out in the table of clause 9.5.4.1 or the schedule for qualification set out in clause 9.5.14, the owner of the tank car or the lining or coating is responsible for:

  1. the performance of a visual inspection, a structural integrity inspection in conformance with the requirements set out in clauses 9.5.6 and 9.5.7, and any other appropriate inspection and test in conformity with this section, if the tank car shows evidence of structural damage or has been subjected to loads in excess of its design requirements;
  2. the performance of a visual inspection and thickness test in conformance with the requirements set out in clauses 9.5.6 and 9.5.8, and any other appropriate inspection and test in conformance with this section, if the tank car shows evidence of damage caused by fire;
  3. the performance of a lining or coating inspection in conformance with the requirements set out in clause 9.5.11 if the lining or coating that was applied for the protection of the tank:
    1. has failed;
    2. was put in contact with a product not compatible with the lining or coating; or
    3. was subjected to a temperature outside the service temperature range of the lining or coating.
  4. a tank car that has been used for dangerous goods with a primary or subsidiary classification of Class 8 must not be used in the handling, offering for transport or transporting of Class 2 dangerous goods unless the tank car is qualified in accordance with the requirements set out in this section.

9.5.6 Visual Inspection

At a minimum, the visual inspection performed under this section must include the following items for the purpose of detecting defects or other conditions that could compromise the reliability of the tank car:

  1. Subject to clause 9.5.6 i., the interior and exterior surface of the tank car tank, except in areas where an insulation system, a safety system, or an internal lining or coating precludes inspection;
  2. The internal surface of the tank car tank after removing an interior lining or coating or before applying a new lining or coating;
  3. The service equipment, including gaskets;
  4. Fasteners;
  5. All bolted, threaded, and quick-coupling closures and their fasteners;
  6. Protective housings;
  7. Excess-flow valves with threaded seats, including an inspection for tightness and operability;
  8. Required markings for correctness, adequacy, and legibility; and
  9. For a Specification 115 tank car, the interior of the inner container and the exterior shell and heads.

9.5.7 Structural Integrity Inspection

9.5.7.1 The structural integrity inspection must be performed by using one or more of the non-destructive evaluation methods set out in Table T2 of the AAR Specifications for Tank Cars publication.

9.5.7.2 At a minimum, the structural integrity inspection must include all of the locations susceptible to damage that could compromise the reliability of the tank car tank, nozzles, welds, and welded attachments, including:

  1. all transverse fillet welds with dimensions greater than 6 mm (¼ in.) within 122 cm (4 ft.) of the bottom longitudinal centreline, except body bolster pad attachment welds;
  2. the termination of longitudinal fillet welds with dimensions greater than 6 mm (¼ in.) within 122 cm (4 ft.) of the bottom longitudinal centreline; and
  3. the tank shell butt welds within 60 cm (2 ft.) of the bottom longitudinal centreline unless the tank car owner can determine by analysis, such as damage tolerance analysis and finite element stress analysis that the tank car will not develop defects or other conditions that could compromise its reliability. The analysis must include a determination of the probable locations and modes of damage to the tank car due to fatigue, corrosion, or accidental damage. As an alternative, service reliability assessment may be used, provided it is supported by analysis of systematically collected data.

9.5.7.3 For a Specification 115 tank car, clause 9.5.7.2 applies only to the outer shell fillet welds and to the non-reinforced, exposed, outer shell butt welds.

9.5.7.4 In the case of tank cars with a lining, the inspection requirements of clause 9.5.7.2 c. do not apply to a tank shell butt weld covered on the outside by a reinforcing plate or any other structural element welded to the tank shell until the time of lining removal or application.

9.5.7.5 In the case of a tank car with an internal patch plate, the structural integrity inspection requirements of this paragraph do not apply to a tank shell butt weld covered on the inside by the patch plate and on the outside by a reinforcing plate or any other structural element welded to the tank shell.

9.5.8 Thickness Test

9.5.8.1 The equipment and procedures used to measure thickness must be capable of an accuracy of ±0.05 mm (±0.002 in.).

9.5.8.2 At a minimum, the thickness test must include measurement of the tank wall thickness at the shell and heads, sumps, protective housings, nozzles, and nozzle reinforcing pads.

9.5.8.3 Subject to clause 9.5.8.4, the thickness test must be performed at the following intervals:

  1. subject to clause 9.5.8 c. ii., and iii., at least once every ten years;
  2. at the time of applying or replacing a lining or coating; or
  3. at least once every five years if:
    1. the tank does not have a lining or a coating;
    2. the tank car is used in the handling, offering for transport, or transporting of dangerous goods that are corrosive to the tank; and
    3. the remaining shell and head thickness of the tank is at or below line C of Figure 9.5.8 c.

where:

A = as-built tank shell or head thickness

B = design minimum tank shell or head thickness, after forming, as set out in section 8

C = inspection frequency adjustment point calculated by subtracting half the value found in the table entitled Allowable Thickness Reductions, as set out in clause 9.5.9 from B, the minimum as-built thickness

D = limit for shell or head thickness (design minimum shell or head thickness minus the allowable shell thickness reduction as set out in clause 9.5.9)

E = limit for shell or head localized thickness (design minimum shell or head thickness minus both the allowable shell thickness reduction as set out in clause 9.5.9 and 1.6 mm [1/16 in.])

F = allowable shell or head thickness reduction as set out in clause 9.5.9

G = additional thickness reduction for localized shell or head areas as set out in clause 9.5.9

9.5.8.4 A thickness test must be performed to verify conformance with the requirements set out in clause 9.5.9 if a material corrosive to the tank has contacted the tank wall and a localized repair of a lining or coating applied for the protection of the tank is performed. The thickness test applies only to the repaired area.

9.5.8.5 Thickness reductions in sumps, protective housings, nozzles and nozzle reinforcing pads must not cause a condition or release of dangerous goods from the tank car that could endanger public safety or compromise their reliability.

9.5.8.6 After any modification or maintenance activity that results in a reduction of the wall thickness of a tank car, a thickness test must be performed in the areas affected by the reduction.

9.5.9 Allowable Thickness Reductions

The allowable thickness reductions of a tank shell and head are specified in the following table entitled Allowable Thickness Reductions. Subject to clauses 9.5.9.1 to 9.5.9.3, a tank car tank with a thickness below the minimum thickness specified in section 8 may continue in service provided any reduction to the design minimum thickness is not greater than the reductions specified in columns 2 and 3 corresponding to the tank test pressures specified in column 1.

Allowable Thickness Reductions

Tank Test Pressure, TP bar (psi) Top Shell and Tank Head mm (in.) Bottom Shell mm (in.)
4.14 (60) ≤ TP < 13.8 (200) 3.2
(1/8)
1.6
(1/16)
TP ≥ 13.8 (200) 0.8
(1/32)
0.8
(1/32)

9.5.9.1 An extra 1.6 mm (1/16 in.) may be added to the values in the table for local reductions. Local reductions are those that do not exceed twenty linear centimetres (eight linear inches), measured at the longest dimension, and are separated from any other local reduction by at least 40 cm (16 in.).

9.5.9.2 The structural strength of the tank must not be affected by any reduction in the tank car tank wall thickness to the extent that the tank car structure is no longer capable of withstanding the minimum loads and stresses to which it was designed.

9.5.9.3 Shell thickness reductions apply only to the outer shell for Specification 115 tank cars. There is no reduction below the design minimum thickness authorized for the inner container.

9.5.10 Safety Systems Inspection

A safety systems inspection must include all safety systems. A safety systems inspection must ensure that all the systems conform to their design requirements and must be adequate to detect defects or other conditions that could compromise the reliability of the safety system. An inspection is not required for a foam or cork insulation system or an insulation system that does not meet the definition of a safety system or that has not been taken into account when establishing the pressure relief devices minimum flow capacities.

9.5.10.1 Acceptable Level of Defects in Thermal Protection Systems

  • a. The maximum permissible void size or total void area is described in the following table:

Maximum Allowable Void Size for Thermal Protection

Void Size/Area Condition
Single isolated void Maximum allowable void is 48 in. on the longitudinal axis of the tank by 16 in. on the circumferential axis (1.2 X 0.4 m). Voids must be separated from other voids by more than one half of the largest dimension or must be considered a single void.
Total void area Maximum allowable total void area is 9% of the total tank surface area.
  • b. The inspection method, technique and procedure must be capable of detecting single square voids of 406 mm (16 in.) X 406 mm (16 in.) at any location on the tank car tank surface.
  • c. Areas of defects other than voids, such as deteriorated thermal protection material, significantly reducing the thermal performance of the material must be considered the same as voids.

9.5.11 Lining or Coating Inspection

9.5.11.1 For the purpose of this clause, commodity pairing means a specific lining or coating that is used in combination with specific dangerous goods.

9.5.11.2 At a minimum, a lining or coating applied for the protection of the tank must have a lining or coating inspection that is adequate to detect defects or other conditions that could compromise the reliability of the lining or coating.

9.5.11.3 The owner of the lining or coating must monitor and maintain a record of the performance of the commodity pairings. The owner of the lining or coating must determine an appropriate lining and coating inspection interval based on the knowledge and experience of the lining or coating owner with respect to the commodity pairing and the information in the records.

9.5.11.4 The inspection interval must not exceed eight years, unless the owner of the lining or coating can establish through documentation for scientific analysis of the commodity pairing that a longer coating or lining inspection interval would not compromise the reliability of the tank car.

9.5.11.5 Any person who offers for transport dangerous goods in a tank car must provide, upon request by the owner of the lining or coating or the owner of the tank car, commodity pairing information to the requesting party.

9.5.11.6 The owner of the lining or coating must provide the inspection procedures and the acceptance criteria for the lining or coating to the tank car owner and to the tank car facility responsible for qualifying the lining or coating. The tank car facility responsible for inspecting the lining or coating must follow the qualification requirements established by the owner of the lining or coating.

9.5.12 Service Equipment Inspection

9.5.12.1 At a minimum, the service equipment inspection must ensure that all of the service equipment conforms to the requirement set out in this standard and be adequate to detect defects or other conditions that could compromise their reliability.

9.5.12.2 Procedures for the inspection and testing of service equipment, including heater systems and pressure-relief devices must conform to the requirements set out in Appendix D of the AAR Specifications for Tank Cars publication.

9.5.12.3 The tank, service equipment, and closures installed, replaced or reinstalled must be leak tested in accordance with clause 9.7.3. The pressure test required after rebuilding service equipment in accordance with par. D3.2.2.5 of the AAR Specifications for Tank Cars publication must conform to appendix T of the AAR Specifications for Tank Cars publication.

9.5.13 Adjustments in Inspection and Test Protocols

9.5.13.1 Each tank car owner must implement a system for the continuing analysis and surveillance of the performance and effectiveness of their inspection and maintenance programs. This system must include a means for the collection and analysis of data relative to the inspection and maintenance requirements set out in this section.

9.5.13.2 The tank car owner must use the collected data to evaluate the maintenance program, inspection intervals and tank car including stub sills, attachments to the bottom shell, service equipment, and lining or coating designs for the purpose of determining appropriate action for the minimization of failure, damage, and deterioration that could compromise the reliability of the tank car.

9.5.13.3 The minimum inspection intervals must not be increased and the qualification requirements set out in clauses 9.5.4 through 9.5.14 must not be reduced unless an equivalency certificate regarding an increase in inspection interval or a reduction in qualification requirements has been issued in conformance with the requirements of the TDG Regulations.

9.5.13.4 When seeking a modification to the interval or requirements of a structural integrity inspection, an owner must provide an engineering analysis, such as damage tolerance analysis or finite element stress analysis. The analysis must include a determination of the probable locations and modes of damage to the tank car due to fatigue, corrosion, or accidental damage. As an alternative, service reliability assessment may be used, provided it is supported by analysis of systematically collected data.

9.5.14 Schedule for Qualification of Tank Cars

9.5.14.1 Subject to clauses 9.5.14.2 and 9.5.14.3, a tank car must be qualified in accordance with the requirements set out in this section on or before the required due date for the qualification of the tank car.

9.5.14.2 In the case of a tank car that met one of the conditions below on July 1, 1998, for a tank car without a metal jacket or a thermal protection system, or between July 1, 1998 and July 1 2000, for a tank car with a metal jacket or a thermal protection system:

  1. conformed to specification 103BW, 111A60W5 or 111A100W5;
  2. was lined with glass, rubber, lead, elastomeric polyvinyl chloride no less than 2.38 mm (3/32 in.) in thickness or elastomeric polyurethane no less than 1.58 mm (1/16 in.) in thickness; or
  3. conformed to specification 105A500W and either was lined with an elastomeric material or had a nickel cladding and was in bromine service;

the tank car must be qualified on or before:

  1. July 1, 2010, for a tank car with a metal jacket or a thermal protection system; or
  2. October 1, 2008 for a tank car without a metal jacket or a thermal protection system built after 1984; or
  3. January 1, 2005 for a tank car without a metal jacket or thermal protection system built before 1985.

9.5.14.3 In the case of a tank car that had a hydrostatic tank test interval greater than ten years, including Specification 103W, 104W, 111A60W1, 111A100W1, and 111A100W3 tank cars, the date for qualification is the midpoint between the required due date and July 1, 1998, for a tank car without a metal jacket or thermal protection system, or July 1, 2000, for a tank car with a metal jacket or a thermal protection system. For example:

  1. A non-jacketed tank car last tested in 1994 and stenciled 2014 needs to be qualified by the end of (2014 - 1998)/2 + 1998 = 2006; and
  2. A jacketed tank car last tested in 1989 and stenciled 2009 needs to be qualified by the end of (2009 - 2000)/2 + 2000 = 2004.5 rounded down to 2004.

9.5.14.4 The first qualification for specification 113 and AAR 204W tank cars must be done:

  1. for tank cars older than ten years, no later than the next pressure-relief device test; and
  2. for other tank cars, no later than ten years after the date of manufacture.

9.6 Acceptable Results of Inspections and Tests

9.6.1 Qualification

A tank car is qualified if it successfully passes the inspection and test requirements set out in this section.

9.6.2 Visual Inspection

A tank car successfully passes the visual inspection if the inspection reveals no defect that may reasonably be expected to cause, before the next inspection is due and under normal conditions of transport, including handling, a condition or release of dangerous goods that could endanger public safety.

9.6.3 Structural Integrity Inspection

A tank car successfully passes the structural integrity inspection if the inspection reveals no visible parent metal crack or other defect that may reasonably be expected to cause, before the next inspection is due and under normal conditions of transport, including handling, a condition or release of dangerous goods that could endanger public safety.

9.6.4 Thickness Test

A tank car successfully passes the thickness test when the tank shell and heads show no thickness reduction greater than that specified in clause 9.5.9.

9.6.5 Safety System Inspection

A tank car successfully passes the safety system inspection if each safety system of the tank car, including:

  1. a thermal protection system;
  2. a tank-head puncture-resistance system;
  3. a coupler vertical restraint system;
  4. an insulation system used to control pressure or outage; or
  5. a system used to protect top or bottom discontinuities;

conforms to the requirements set out in this standard including clause 8.3.19 or a special provision of schedule 1 for insulation systems and the inspection reveals no defect larger than the limits specified in clause 9.5.10.1 or that may reasonably be expected to cause, before the next inspection is due and under normal conditions of transport, including handling, a condition or release of dangerous goods that could endanger public safety.

9.6.6 Lining or Coating Inspection

A tank car successfully passes the lining and coating inspection if the inspection reveals no defect that may reasonably be expected to cause, before the next inspection is due and under normal conditions of transport, including handling, a condition or release of dangerous goods that could endanger public safety.

9.6.7 Service equipment

A tank car successfully passes the service equipment inspection when the equipment conforms to this standard and the applicable provisions of Appendix D of the AAR Specifications for Tank Cars publication and the inspection reveals no defect that may reasonably be expected to cause, before the next inspection is due and under normal conditions of transport, including handling, a condition or release of dangerous goods that could endanger public safety.

9.6.8 Tank Test

A Specification 115 tank car or a riveted tank car successfully passes the tank test if the tested tank does not show evidence of yielding, leakage or other defect that may reasonably be expected to cause, before the next inspection is due and under normal conditions of transport, including handling, a condition or release of dangerous goods that could endanger public safety.

9.6.9 Stub sill inspection

A tank car successfully passes the stub sill inspection if the inspection reveals no visible parent metal crack or other defect that may reasonably be expected to cause, before the next inspection is due and under normal conditions of transport, including handling, a condition or release of dangerous goods that could endanger public safety.

9.7 Maintenance

9.7.1 Periodic Analysis and Surveillance

An owner of a tank car, lining or coating, or service equipment is responsible for ensuring that each tank car facility conforms to the owner's maintenance program through periodic analysis and surveillance of the maintenance activities of the tank car facility.

9.7.2 Coating of Tank Exterior and Jacket Interior

If the jacket of a tank car is completely removed for maintenance purposes, the exterior surface of the tank car tank and the interior surface of the tank car jacket must have a protective coating applied or renewed if either of these surfaces is found to be inadequately protected against corrosion.

9.7.3 Leak Testing

9.7.3.1 Subject to clause 11.2, a successful leak test conforming to Appendix T of the AAR Specifications for Tank Cars publication is required at the time of service equipment qualification or after any modification or any maintenance activity involving the removal of any service equipment, unless the tank car service equipment arrangement precludes it. The leak test must verify that service equipment closures, including auxiliary devices when so equipped and its connection to the tank car tank do not leak. The leak test must be performed on a tank car with all service equipment in place and functional.

9.7.3.2 In addition to the requirements of clause 9.7.3.1, maintenance and qualification of service equipment, involving resealing, rebuilding or remanufacturing must conform to Appendices D and T of the AAR Specifications for Tank Cars publication.

9.7.3.3 A leak test is not required when a pressure-control valve or a pressure-relief valve on a tank car transporting a cryogenic liquid, or a pressure-regulating valve on a tank car transporting carbon dioxide, has leaked because of ice build-up and is subsequently made to reseat properly.

9.7.4 Exception to Leak Testing

A leak test is not required if the removal of the service equipment is for the sole purpose of loading or unloading the dangerous goods and the service equipment is designed for loading or unloading, including the removal of pipe plugs and caps, quick disconnects and their closures, hinged manway covers, and fill hole covers.

9.7.5 Access Openings in Jackets and Tank-head Puncture-resistance Systems

  1. When sections of tank-head puncture-resistance systems are cut out for any reason, the sections must be replaced using a full penetration weld or other method approved by the committee, to restore the full strength of the original system.
  2. When sections of the tank jacket are cut out for any reason, the sections must be replaced to restore the original integrity, and made weather-tight.
  3. When sections of thermal protection are removed for any reason, the sections must be replaced with a system providing equivalent thermal performance and fire resistance.

9.8 Reporting and Record Retention Requirements

9.8.1 Certification and Representation

The manufacturer of a tank car must certify that all of the requirements set out in this standard, including inspections and test that are required for the qualification of the tank car, have been performed by signing the Certificate of Construction, Form AAR 4-2, and by marking the tank with the appropriate tank car specification to which the tank car was manufactured. The manufacturer must retain the reports relating to the manufacture and qualification of the tank car. The owner of the tank car must retain, throughout the period of ownership of the tank car plus one year after the change of ownership, the Certificate of Construction and any documents relating to subsequent approvals and qualifications, which certify that the tank car identified in the documentation conforms to the requirements set out in the applicable specification. Upon a change of ownership, the requirements set out in par. 1.3.15 of the AAR Specifications for Tank Cars publication apply.

9.8.2 Qualification Reporting

A written or electronic report must be provided for a tank car that has been qualified in conformance with the requirements set out in this section. The owner must retain a copy of the report until successfully completing the next qualification of the same type. The report must include the following information:

  1. Qualification items;
  2. The results for each qualification item;
  3. Tank car reporting mark and number;
  4. Tank car specification;
  5. Qualification date for each qualification item;
  6. Location and description of defects and method used to repair each defect;
  7. The name and address of the tank car facility and the name of the inspector; and
  8. The facility registration symbol.

9.9 Periodic Retest and Inspection of Ton Containers

9.9.1 General

A ton container and its pressure-relief devices must be inspected and retested periodically in conformance with the requirements set out in this clause.

9.9.2 Inspection and Tests

9.9.2.1 Subject to clause 9.9.2.8, a ton container must be subjected to the specified hydrostatic pressure and its permanent expansion must be determined by a method that conforms to the requirements set out in CGA Pamphlet C 1 except that the use of a calibrated cylinder or ton container for the test system accuracy verification is not required. The pressure must be maintained for as long as necessary to ensure complete expansion of the ton container, or for 30 s, whichever is the greater. The pressure gauge must permit a measurement to an accuracy of ±1% at the test pressure, and the expansion gauge must measure the total expansion to an accuracy of ±1%. The expansion must be recorded in cubic centimetres. A ton container successfully passes a hydrostatic pressure test when the permanent volumetric expansion does not exceed 10% of the total volumetric expansion at the test pressure and the ton container does not show evidence of yielding or leakage.

9.9.2.2 Subject to clause 9.9.2.8, and in addition to the hydrostatic pressure test requirements of clause 9.9.2.1, a ton container must be subjected to an air-pressure test at a pressure equal to or greater than 6.9 bar (100 psi) under conditions favourable to the detection of any leakage. A ton container successfully passes an air-pressure test when there is no evidence of yielding or leakage.

9.9.2.3 An internal and external visual inspection must be performed. A ton container successfully passes the visual inspection if it meets the criteria set out in CGA Pamphlet C 6.

9.9.2.4 A reclosing pressure-relief device must be tested by pressurizing with air or other gas. A reclosing pressure-relief device installed on a ton container must conform to the requirements set out in column 5 and column 6 of the Retest Table of clause 9.9.2.6. A reclosing pressure-relief device successfully passes the test if the measured start-to-discharge pressure of the device is at or below the specified start-to-discharge pressure and the measured vapour-tight pressure is at or above the specified vapour-tight pressure.

9.9.2.5 Rupture discs and fusible plugs must be removed from the tank and visually inspected.

9.9.2.6 Subject to clause 9.9.2.6.1 a ton container must be retested as specified in the following retest table.

Retest Table

Specification Maximum Retest Interval years Retest Pressure bar (psi) Specified Pressure for Reclosing Pressure-relief Device bar (psi)
Tank Pressure-relief Device Hydrostatic Pressure Test Start-to-discharge Vapour-tight
106A500 5 2 34.5 (500) 25.9 (375) 20.7 (300)
106A500X 5 2 34.5 (500) 25.9 (375) 20.7 (300)
106A800 5 2 55.2 (800) 41.4 (600) 33.1 (480)
106A800X 5 2 55.2 (800) 41.4 (600) 33.1 (480)
106A800NCI 5 2 55.2 (800) 41.4 (600) 33.1 (480)
110A500W 5 2 34.5 (500) 25.9 (375) 20.7 (300)
110A600W 5 2 41.4 (600) 31.0 (450) 24.8 (360)
110A800W 5 2 55.2 (800) 41.4 (600) 33.1 (480)
110A1000W 5 2 69.0 (1000) 51.7 (750) 41.4 (600)

9.9.2.6.1 Pressure-relief devices of the spring-loaded type on tanks used exclusively for fluorinated hydrocarbons that do not contain components that are corrosive to the tank or to the pressure-relief device may be retested every five years.

9.9.2.7 The month and year of the inspections and tests performed in conformance with the requirements set out in clause 9.9 must be plainly and permanently stamped into the metal of one head or chime of each ton container which successfully passes the periodic retest and inspection; for example, "01-12" for a retest and inspection performed in January of 2012. If the ton container was visually inspected in conformance with the requirements set out in clause 9.9.2.8 and the pressure tests set out in clauses 9.9.2.1 and 9.9.2.2 were not performed, the month and date of the retest and inspection must be followed by a "V"; for example, "01 12 V" for a visual inspection performed in January of 2012. Dates of previous retests and inspections and all specified markings must be kept legible.

9.9.2.8 In the case of a ton container that is used exclusively for fluorinated hydrocarbons that do not contain components that are corrosive to the tank, the requirements of clauses 9.9.2.1 and 9.9.2.2 do not apply.

9.9.3 Reporting and Records Retention

9.9.3.1 The results of the hydrostatic pressure test, air-pressure test, and visual inspection must be collected and recorded.

9.9.3.2 A report must be produced which must include:

  1. Date of inspection and test;
  2. Specification;
  3. Ton container identification (registered symbol, serial number, date of manufacture and ownership symbol);
  4. A statement pertaining to the need for refinishing or recoating the ton container;
  5. Conditions checked (leakage, corrosion, gouges, dents, digs, broken or damaged chime or protective ring, fire damage, internal condition);
  6. Test pressures;
  7. Results of tests;
  8. Disposition of ton container (returned to service, returned to manufacturer for repair, or scrapped); and
  9. Identification of the facility and person conducting the retest or inspection.

9.9.3.3 The owner of a ton container must retain the reports throughout the period of ownership plus one year after the change of ownership. Upon a change of ownership, the owner must transfer the reports to the new owner. The person or facility performing the hydrostatic pressure test, air-pressure test, and visual inspection must keep the reports for at least one retest and inspection interval plus one year.

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