PVC steel wire hose is a common material for industrial and civil use. To guarantee the quality, supplier will test it after production. While the vacuum property test is one of them. This is to test the change on hose surface at vacuum. While there are 2 methods to do such work. Let me show you next.
First is the length of PVC steel wire hose
The min length (not include joint) should be 5 times of the nominal inner diameter. Or it should be at least 1 meter. In terms of the 2 data, you can choose the longer one. But for the hose less than 1 meter, you can pick the whole piece or the assembly.
For the hose smaller than DN80, you need to lay the hose on a plat. Then block one end with a metal plug. This is to make sure there will not be leakage. At this moment, insert a solid ball into the hose. Then connect the other end to vacuum pump. After that, reduce the pressure to the test standard and remain for 10 minutes. During this, you can also check if there was any hollow on the surface. Last you need to incline the tested hose and make sure the ball can go through. Meanwhile, you can check if there was any other problems.
Test method for large size PVC steel wire hose
For the transparent steel wire hose larger than DN80, you need the other method. You can install a transparent sealing plug on one side. Then connect the other side to pump. During the test, you can check the hose if there was any hollow.