Hunan Steel Industrial Zone, No.9 Xiangfu Road, Yuhua District, Changsha, China
Pup joints are non-standard lengths of piping used to adjust the height of full length tubing, drill pipe, line pipe, or casing strings. Strings of pipe are assembled with standard length tubular goods that are typically 31 feet in length. As the drill string, production tubing, or casing is lowered into the well bore a pup joint is added to the pipe string in order to adjust the length of the string to its exact requirements.
Pup joints are offered in either two or five foot increments with custom lengths available on request. They are distinguished by the type of piping they are used with such as casing pup joints, tubing pup joints, or drill pipe pup joints. They are also distinguished by the nominal outside diameter of the pipe itself ranging from ¾" to 20" or more dependent on the type of tubular goods they mate with.
Standards: API Spec 5CT - This Standard specifies the technical delivery conditions for steel pipes (casing, tubing and pup joints), coupling stock, coupling material and accessory material and establishes requirements for three Product Specification Levels (PSL-1, PSL-2, PSL-3). The requirements for PSL-1 are the basis of this Standard. The requirements that define different levels of standard technical requirements for PSL-2 and PSL-3, for all Grades except H-40, L-80 9Cr and C110, are contained in Annex H.