BSPT THREAD CHART SIZES DIMENSIONS CALCULATOR

BSPT Thread Chart Calculator for British Standard Pipe Taper Thread form where pressure-tight joints are made on the threads. The BSPT thread chart calculator shows sizes, dimensions, tolerances and designation for jointing pipe threads for thread sizes from 1/16 to 6 according to ISO 7-1 standard. The thread form follows the British Standard Whitworth thread.

Some important notes from the ISO 7-1 standard:

- Threads are taper external, parallel internal or taper internal and are intended for use with pipes suitable for threading and for valves, fittings or other pipeline equipment interconnected by threaded joints.

-An appropriate jointing medium should be used on the thread to ensure pressure-tight joints.

-ISO 7-2 gives details of methods of verification of jointing thread dimensions and form and recommended gauging systems.

- The ISO 7-1 thread shall be a right-hand thread unless otherwise specified.

- The taper is 1 to 16, measured on the diameter.

British Standard Pipe Taper Thread (BSPT) per ISO 7-1

 INPUT PARAMETERS Parameter Value Pipe Thread Size 1/16 1/8 1/4 3/8 1/2 3/4 1 1 1/4 1 1/2 2 2 1/2 3 4 5 6

 RESULTS Parameter Value Pipe Thread Size - --- --- Threads per inch (25.4 mm) n --- Pitch of Thread P --- mm Height of Thread h --- Diameters at gauge plane Major (gauge diameter) d --- Pitch d2 --- Minor d1 --- Gauge length (external thread) Nominal --- --- Tolerance in mm (+/- T1/2) --- Tolerance in turns of thread --- --- Max --- --- mm Min --- --- Tolerance on position of gauge plane on internal thread Tolerance in mm (+/- T2/2) --- Tolerance in turns of thread --- --- Length of useful external  thread not less than For nominal gauge length --- --- mm For maximum gauge length --- For minimum gauge length --- Fitting allowance in mm --- --- turns of thread --- --- Diameter tolerance on parallel internal threads --- --- --- mm

Definitions:

Gauge diameter: Major diameter of the external or internal thread at gauge plane.

Gauge plane: Plane, perpendicular to the axis of the taper thread, at which the major cone has the gauge diameter.

Gauge length: The distance from the gauge plane to the smaller end of the thread on an external thread.

Major cone: The imaginary cone which just touches all crests of a taper external thread or all roots of a taper internal thread.