How to install compression fittings?

Many customers do not know how to install the compression fittings, in this article , it will introduce how to install the compression fitting :

1. Saw the appropriate length of seamless steel pipe to remove port burrs. The end face of the pipe should be perpendicular to the axis, and the angle tolerance should not be greater than 0.5 degrees. If the pipe needs to be bent, the length of the straight segment from the end face of the pipe to the bend must not be less than three times the length of the nut.

2. Put the nut and ferrule on the seamless tube, pay attention to the direction of the nut and ferrule, and do not install it in reverse.

3. Apply lubricating oil to the threads and ferrules of the pre-assembled fitting body, insert the pipe into the fitting body, the pipe must be inserted to the end, and tighten the nut by hand.

4. Tighten the nut until the ferrule jams the tube, this turning point can be felt by the increase in tightening torque.

5. After reaching the pressure point, tighten the hold-down nut for 1/2 turn.

6. Remove the pre-assembled fitting body and check the insertion of the ferrule edge, the visible protrusion band must fill the space on the ferrule endface. The ferrule can be rotated slightly, but not axially.

7. For final installation, lubricate the joint body and threads in the actual installation, and tighten the compression nut with it until the tightening force can be felt, and then tighten it for 1/2 turn to complete the installation.

Thread difference between BSPT, BSPP & NPT

Different thread sealing depending on the geographical region,size of the pressure system and the environment. Fox example, In Asia, such as China, Korea, Japan etc normally use BSPT; In U.S, Canada etc always use NPT, then for BSPP thread most popular in UK, Europe, Australia, New Zealand and South Africa. While one sealing style is not inherently better than another each style has its application.

NPT Connections ( National Pipe Thread)- US & Canada

It is according to ANSI/ASME B1.20.1 Pipe Threads. 60 degree of thread angle. NPT male adapters have a taper thread that wedges into the female NPT adapter.

BSPT Connections (British Standard Pipe Taper)- China, Korea, Japan

BSPT thread is similar to NPT except for one important difference. The angle across the flanks of threads is 55 degrees instead of 60 degree as it is for NPT thread. Thus an NPT male thread could fit into BSPT female thread, but couldn’t sealing.

BSPP Connections ( British Standard Pipe Parallel)- UK, Europe, Australia,South Africa

BSPP thread is also British standard. It is a parallel thread fitting that uses a bonded seal ring to do the sealing. For historical reasons, BSPP has other different names at the same time. Such as BSPF ( British standard pipe fitting), BSPM(British Standard Pipe Mechanical) and PS (British Standard Pipe Straight) and so on.

For our thread valves & thread fittings, thread standard always most important for manufacture.

So please pay more attention about these difference.

BSPT & BSPP both referred to as BSP, so most of our customer maybe only told you needs BSP thread. Normally for female thread, 99% is BSPP. For male thread, BSPT & BSPP, 50%.

(1) BSPP male thread could 100% connected with BSPP female thread,but NOT MATCH BSPT Female Thread

(2) BSPT male thread couldn't 100% connected with BSPP female thread, needs using PTFE tap.