MM threaded stainless steel unions are mainly made from 304,316 stainless steel.
Normal working pressure is 2 Mpa.
The thread type can be: NPT, BSP, BSPT etc.
Our main sizes are from 1" to 8".
There are three types according to the structures as follows:

Notes:
The first two types of connnection are without the plastic washer, it can bear higher temperature than
the third type of connection. Because there is a plastic washer in the flat uions. Pictures for comparision
are as follows.
![]() |
|
The difference between the bsp, bspt and npt thread type are as follows.
![]() | ![]() |
Elbow unions disassembled.
![]() | ![]() |