Section 7 Materials

7.1.1 The type and grade of materials chosen for the pipeline, valves, associated equipment, risers, weight coating and corrosion protection are to be in accordance with LR's Rules for the Manufacture, Testing and Certification of Materials, January 2016 or an approved National or International specification. In cases when a specification is not covered by LR's Rules full details of the material specification and all properties are to be submitted for approval.

7.1.2 Materials complying with National or proprietary specifications may be accepted provided these specifications give satisfactory equivalence to the above requirements.

7.2.1 Paint or protective coatings are generally to be chosen in conjunction with the compatibility of any weight coating to be applied and with the system of cathodic protection, see also BS 5493 - Code of Practice for Protective Coating of Iron and Steel Structures against Corrosion.

7.2.2 The performance of the coating materials used should be proven by previous service or by extensive and documented laboratory testing.

7.2.3 Preparation of the pipeline surface before coating is to comply with the approved specification relating to that material, see also BS 4232 - Specification for Surface Finish of Blast-Cleaned Steel for Painting, is a guide for equivalence.

7.3.1 The method of internal protection is to take into account the corrosivity, bacterial content, solids/abrasive content, flow characteristics and temperature and pressure. Any future change of use should be allowed for.

7.3.2 Materials or systems (e.g. liners) are to be suitable for the service nature of fluid to be conveyed. Propriety specifications and in-service history are to be submitted as required by LR.

7.3.3 Where internal protection is proposed by use of corrosion inhibitors the properties, compatibility and effect on fluid conveyed are all to be documented and submitted.

7.4.1 The concrete and reinforcement materials are to have adequate strength, adhesion and properties to assist corrosion protection of steel.

7.4.2 The constituents of the concrete, the mix, admixtures, compaction, curing and method of placement are to be approved by LR. They are also to comply with relevant codes.

7.4.3 The reinforcement bars are to comply, as a minimum, with BS 4449 - Specification for Hot Rolled Steel Bars for the Reinforcement of Concrete & BS 4466 - Specification for Bending Dimensions and Scheduling of Reinforcement for Concrete.

7.5.1 The pipelines are to comply, as a minimum, with the API Std 5L Specification for Line Pipe. Due consideration is to be given to temperature and other environmental conditions on the performance of the material, including toughness at the minimum operating temperature, the effects of corrosion, and other forms of deterioration both in service and whilst being stored or handled.

7.5.2 For sour gas service suitable steels are to be selected to eliminate the possibility of cracking or embrittlement as a result of H₂S being contained in the fluid flow. The NACE Standard MR-01-75 - Material Requirement - Sulphide Stress Cracking Resistant Metallic Material for Oil Field Equipment, may be applied.

7.5.3 Steel grades for operation in areas where the design air temperature is below 0°C and in severe ice conditions, e.g. arctic waters, will be specially considered.

7.5.4 An approved system of corrosion control is to be fitted and full details are to be submitted.

7.5.5 Pig traps are to be designed to the requirements of an national pressure vessel code such as BS 5500 - Specification for Unfired Fusion Welded Pressure Vessels.