ISO 11960:2004 (API 5CT)
Petroleum and natural gas industries -- Steel pipes for use as casing or tubing for wells
ISO 11960:2004 specifies the technical delivery conditions for steel pipes (casing, tubing, plain end casing liners and pup joints), coupling stock and accessories and establishes requirements for three Product Specification Levels (PSL-1, PSL-2, PSL-3). The requirements for PSL-1 are the basis of ISO 11960:2004. The requirements that define different levels of standard technical requirements for PSL-2 and PSL-3, for all Grades except H-40 and L-80 9Cr, are contained in Annex H.
ISO 11960:2004 is applicable to the following connections in accordance with API Spec 5B:
-- short round thread casing (STC);
-- long round thread casing (LC);
-- buttress thread casing (BC);
-- extreme-line casing (XC);
-- non-upset tubing (NU);
-- external upset tubing (EU);
-- integral joint tubing (IJ).
For such connections, ISO 11960:2004 specifies the technical delivery conditions for couplings and thread protection. Supplementary requirements that may optionally be agreed for enhanced leak resistance connections are given in Annex A.11 (SR22).
ISO 11960:2004 can also be applied to tubulars with connections not covered by ISO/API standards.
For pipes covered by ISO 11960:2004, the sizes, masses and wall thicknesses as well as grades and applicable end finishes are given.
By agreement between the purchaser and manufacturer, ISO 11960:2004 can also be applied to other plain end pipe sizes and wall thicknesses.
The four groups of products to which ISO 11960:2004 is applicable include the following grades of pipe:
-- Group 1: All casing and tubing in Grades H, J, K and N;
-- Group 2: All casing and tubing in Grades C, L, M and T;
-- Group 3: All casing and tubing in Grade P;
-- Group 4: All casing in Grade Q.
Casing sizes larger than Label 1: 4-1/2 but smaller than Label 1: 10-3/4 may be specified by the purchaser to be used in tubing service.
Supplementary requirements that may optionally be agreed between purchaser and manufacturer for non-destructive examination, coupling blanks, upset casing, electric-welded casing, impact testing, seal ring couplings and certificates are given in Annex A.
ISO 11960:2004 is not applicable to threading requirements.