Scope and technical regulation EN ISO 13680
The international standard EN ISO 13680 defines strict technical requirements for the supply of seamless casing and tubing, as well as coupling stock, manufactured from corrosion-resistant alloys. EV Group China products fully comply with these standards, ensuring reliability in aggressive operating environments.
The standard classifies product quality into two Product Specification Levels (PSL):
- PSL-1: the basic level of requirements, regulating the fundamental physical and mechanical characteristics of the products.
- PSL-2: an enhanced level, including extended requirements for corrosion resistance and resistance to sulfide stress cracking (SSC) in accordance with ISO 15156-3 protocols and Annex G of the standard.
EV Group China provides the option of supplying PSL-2 level products instead of PSL-1. All corrosion-resistant steels and alloys used are classified according to the requirements of ISO 4948-1 and ISO 4948-2.
Material classification according to the standard
Depending on the alloying composition and crystal structure, materials are divided into four functional categories:
- Category 1: Martensitic and martensitic-ferritic steels.
- Category 2: Austenitic-ferritic steels (duplex and super-duplex grades).
- Category 3: Austenitic iron-nickel alloys.
- Category 4: Austenitic nickel alloys.
It is important to note that not all PSL-1 steel grades automatically meet the cracking resistance requirements of ISO 15156-3, which limits their use in critical PSL-2 conditions.
Chemical composition and corrosion resistance
The chemical composition of materials for the PSL-1 level is regulated by Table A.2. For PSL-2 level products, element content standards are provided in Tables A.28 and C.28. Particular attention is paid to Category 2 materials: for them, a mandatory requirement is proven resistance to pitting corrosion, the parameters of which are recorded in the corresponding tables of the standard.
Geometric parameters and tolerances
During pipe production, EV Group China strictly adheres to dimensional characteristics, including outside diameter, wall thickness, and mass per unit length, as specified in Tables A.15 and C.15. High precision in diameter calibration (up to two decimal places) ensures full component interchangeability. Products are supplied in length ranges corresponding to the regulations of Tables A.16 or C.16.