scope:

Foreword.

(a) This recommended practice was prepared by and is under the jurisdiction of the API Committee on Standardization of Oil Country Tubular Goods.

(b) Other specifications and recommended. practices under the jurisdiction of ,this committee are:

5A: Specification for Casing, Drill Pipe and Tubing.

Covers seamless steel drill pipe. and seamless and welded steel. open-hearth-iron and wrought-iron casing and tubing in various grades. Processes of manufacture, chemical and physical requirements. methods of test. and dimensions are included. also thread and gage dimensions. gaging practice. and requirements on couplings and thread protectors.

5B: Specification for Inspection of Threads.

Covers methods of inspecting internal and external pipe threads and descriptions of instruments for measuring thread elements.

5L: Specification for Line Pipe.

Covers seamless and welded steel. seamless and welded open-hearth-iron. and welded wrought-iron line pipe in various grades. It includes standardweight threaded line pipe. and regular-weight. special. extra-strong, and double-extra strong plain-end line pipe. Processes of manufacture, chemical and physical requirements, methods of test, and dimensions are included, also thread and gage dimensions, gaging practice, and requirements on couplings and thread protectors.

5LX: Specification for High-Test Line Pipe.

Covers various grades of seamless and welded steel line pipe having greater tensile and bursting strengths than for pipe manufactured under API 5Al: Std 5L. Processes of manufacture, chemical and physical requirements. methods of test and dimen. sions are included. Bulletin on High-Strength Casing Joints. Gives minimum performance properties of proposed API hlgh-strength casing joints.

5C2: Bulletin on Performance Properties of Casing and Tubing.

Gives collapsing pressures, internal yield pressures. and joint strengths for easing and tubing conforming to API Std SA.

(c) No recommendations on materials for use as thread compounds are given herein. An investigation of such materials by the Institute is expected to provide information on which recommendations can be based at a later date. For the present it is suggested that the selection of a thread compound be given careful consideration by the user, bearing in mind that a satisfactory compound should possess certain properties, the major of which are (1) to lubricate the thread surfaces to facilitate joint make-up and break-out without galling, and (2) to seal voids between the mating thread surfaces and effectively prevent leakage.

(d) No recommendations are given herein on materiaLs, chemicals, or coatings for the protection of tubular products from corrosion or the control of corrosive conditions. Several organizations are actively investigating such corrosion problems and it is suggested that use be made of the latest information available on this subject.