Conversion table Thread BSP

BSP
BSP stands for British Standard Pipe and is a type of thread used for pipes and fittings in the United Kingdom and other countries that follow this standard. BSP threads are also known as parallel threads because the threads run parallel to the axis of the pipe or fitting.

There are two types of BSP threads: BSP parallel thread (BSPP) and BSP tapered thread (BSPT). BSPP threads have threads of equal size and spacing, whereas BSPT threads taper towards the tip of the thread.

BSP threads are mainly used for water and gas pipes, hydraulic systems, and, in some cases, for pneumatic applications. It is important to ensure that the thread on the pipe or fitting matches the BSP specification to guarantee a good fit and seal.

How to Measure BSP Threads
Below is a table showing all the sizes corresponding to BSP threads.

Sometimes it is assumed that a 1’’ thread is 25 mm, but this is not correct. BSP threads have different measurements for both internal and external threads.

The best way to measure the thread is with a caliper. You can do this by placing the caliper on (not between) the threads.

Example of the 1’’ thread:
If it is a 1’’ external thread, the diameter is 33.2 mm.

If it is a 1’’ internal thread, the diameter is 30.2 mm.