ISO 21809-3:2016规定了ISO 13623中定义的石油、石化和天然气行业所用管道运输系统埋管和水下部分无缝或焊接钢管的现场接头涂层要求。ISO 21809的本部分规定了管道和配件（部件）焊接后裸露在钢表面上的防腐涂层的鉴定、应用和测试。 ISO 21809-3:2016在表1中定义并编码了管道的不同类型现场接缝涂层。 ISO 21809-3:2016未涉及额外机械保护、隔热或混凝土重量接缝填充的要求- 涂层管道。 注:根据ISO 21809本部分的要求进行涂层的管道和配件的现场接头被认为适合通过阴极保护进行进一步保护。

ISO 21809-3:2016 specifies requirements for field joint coating of seamless or welded steel pipes for buried and submerged sections of pipeline transportation systems used in the petroleum, petrochemical and natural gas industries as defined in ISO 13623. This part of ISO 21809 specifies the qualification, application and testing of the corrosion protection coatings applied to steel surfaces left bare after the joining of pipes and fittings (components) by welding. ISO 21809-3:2016 defines and codifies in Table 1 the different types of field joint coatings for pipelines. ISO 21809-3:2016 does not address requirements for additional mechanical protection, for thermal insulation or for joint infills of concrete weight-coated pipes. NOTE Field joints of pipes and fittings coated in accordance with this part of ISO 21809 are considered suitable for further protection by means of cathodic protection.