Once the equipment is finished in the construction phase (machining and welding) and has already been dimensionally inspected by our quality control personnel, the next phase in its manufacturing process are the tests, where it will be subjected to verify different aspects. In our filtration equipment we basically carry out three types of tests: tests on weld joints or cast parts, pressure test of the assembly and functional test in case the equipment has moving parts.
Below, we explain each of these tests.
Tests on weld joints
The tests carried out on weld joints allow us to evaluate the quality of the joints made and to know that the manufacturing process has been optimal. The type of tests carried out are the so-called “Non-Destructive Tests” or NDT, a type of test that allows us to verify various characteristics without having to destroy or damage the piece where they are being applied.
In our case, we carry out three types of Non-Destructive Tests.
The first of these would be the performance of X-rays or Ultrasounds on the joints. With this test we can verify that inside of the weld does not present defects that could be a problem for the tightness or in the long term could cause a problem.
Another of the tests that we carry out is the Penetrating Liquids or Magnetic Particles. This is a superficial NDT that allows us to see the surface of the joints in greater detail and verify and confirm that both their appearance and finish are adequate and do not present defects that could be the origin of a failure.
And finally, another type of test that we can carry out is the surface Hardness Tests. With this test we can verify the thermally affected area of the weld and confirm that the properties of the material have not been altered.
Pressure tests
Once the NDT has been carried out on the welds, the next step is to verify the tightness of the entire equipment. This is why the equipment is fully assembled and prepared for a pressure test.
This test consists of filling the equipment with water and putting it at 1.5 times the Design Pressure of the equipment. When the equipment is pressurized, it is verified that there are no leaks through the joints, both bolted and welded, to confirm the tightness of the equipment. The pressure is maintained for a period of approximately 15 to 60 minutes.
After this time, the pressure is released, the equipment is emptied, and the inside is cleaned.
Functional tests
After the NDT and pressure tests, if the equipment has moving parts, such as hinges, davit arms, valves, etc., a functional test is finally carried out. With all the equipment assembled, this test consists of verifying the movement of these moving parts, confirming that the assembly and its operation are correct.
Once all these tests have been carried out, the equipment is disassembled again and is ready to continue to its next phase of manufacturing: finishing.