American Petroleum Institute

Specification for Threading, Gauging and Thread Inspection of Casing, Tubing, and Line Pipe Threads - FIFTEENTH EDITION
 N SPEC 5B

Annotation

COVERAGE

This Specification covers dimensions and marking requirements for API Master thread gauges. Additional product threads and thread gauges as well as instruments and methods for the inspection of threads for line pipe, round thread casing, buttress casing, and extreme-line casing connections are included. It is applicable when so stipulated in the API standard governing the product. The inspection procedures for measurements of taper, lead, height, and angle of thread are applicable to threads having 111/2 or less turns per in. (111/2 or less turns per 25,4 mm). All thread dimensions shown without tolerances are related to the basis for connection design and are not subject to measurement to determine acceptance or rejection of product.

By agreement between the purchaser and manufacturer, the supplemental requirements for Enhanced Leak Resistance LTC in SR22 shall apply.

INSPECTION

Thread inspection applies at the point of manufacture prior to shipment, to inspection at any intermediate point, to inspection subsequent to delivery at destination, and to inspection by inspectors representing the purchaser or the manufacturer. The manufacturer may, at his or her option, use other instruments or methods to control manufacturing operations; but acceptance and rejection of the product shall be governed solely by the results of inspection made in accordance with the requirements of this Specification.

OTHER REQUIREMENTS

The applicable product specification should be consulted for requirements not given herein.