DNV DNV-CP-0244 PDF

Scope and application

This programme is applicable for the approval of material manufacturers of:

— rolled austenitic and ferritic-austenitic steel products

as referred in the Society's rules and standards. For a description of general requirements, conditions, procedures and documentation requirements related to the approval, see DNV-CP-0346 which shall be applied in combination with this programme. For steel rolling mills that operate their own steelmaking facilities, the requirements of DNV-CP-0242 apply in addition to this programme.

This programme is applicable too, for rolled bars made of martensitic, martensitic-austenitic, precipitation hardened or ferritic stainless steel. However, for these steels the requirements will be specified by the Society case-by-case.

This AoM programme is applicable for the approval of manufacturers of products indicated in Table 1 as given in DNV-RU-SHIP Pt.2 Ch.2 and relevant parts of other applicable DNV rules and standards.

The product(s) used for approval testing (see Sec.3) will place limitations on the range of approval. The approval will be limited to:

— each steel grade listed below

— each product category, see Table 1

— each kind of product form (plates, strips/coil, sections, bars etc.)

— particular processing route and manufacturing variables

— maximum tested thickness (t) or diameter.

Approval of one product form will not cover other product forms (example: round/flat bars will not cover sections). However, approval for one grade of steel may also cover approval other grades, i.e. without additional approval testing. This is based on certain approval principles as given in App.A.

Approval is given to the following typical product categories:

— rolled stainless steels for structural and low temperature service

— stainless steel strips/coil

— rolled round bars

— austenitic stainless

— duplex stainless.

Approval is given to the following typical manufacturing variables in processing routes:

— steelmaking process and secondary refining

— casting method (CC, IC etc.)

— dimensions of starting material

— reduction ratio

— condition of supply (e.g. solution heat treated condition).

When applicable, approval will be given for the following additional conditions:

— austenitic and duplex stainless steel grades for low temperature applications

— rolled round bars not intended for structural application, e.g. intended for machinery components (as a substitute for forged bars). For these products the requirements for reduction ratio, sampling, acceptance criteria for mechanical properties and visual inspection and NDT shall comply with DNV-RU-SHIP Pt.2 Ch.2 Sec.6, as relevant. Approval test scope is given in this approval programme

— where approval is applied for steel grades specified according to other relevant international standards, approval and test scope shall be agreed with the Society on case-by-case basis.

Starting material /semi-finished steel products shall be produced at works approved by the Society:

— when steel rolling mill operates their own steel making and produce their semi-finished steel products (slabs/ingots/etc.), the manufacturer shall also use the separate approval programme DNV-CP-0242to approve these facilities

— when raw materials for steel rolling mill (slabs/ingots/etc.) are not produced at the rolling mill, semifinished steel products shall be procured from DNV approved steelmakers.

The manufacturer’s own heat treatment facilities shall be evaluated and approved by the Society, either under this approval programme, or as an approved 'heat-treatment workshop' based on the approval programme DNV-CP-0351.

Where steel plates shall be repaired by welding, or two or more items are joined by welding to form a composite item, the manufacturer's welding shop shall either be approved for welding in accordance with this programme, or be approved as welding workshop. For welding workshop approval, see DNV-CP-0352.

Approval requirements related to subcontracted heat treatment are specified in DNV-CP-0346.

Manufacturers and works carrying out decoiling of strip and coiled products are not covered by this programme, but need separate approval according to DNV-CP-0349.