How to detect the sealing of stainless steel duct welding?

After the stainless steel air duct is welded, the sealing performance of welding can be tested by the following methods:

First, the appearance inspection

First, conduct an intuitive appearance inspection.

Observe the weld surface: check whether the weld is uniform and smooth, and whether there are obvious defects such as cracks, pores and slag inclusion. If the weld surface is rough, discontinuous or has obvious pits, it may affect the sealing performance.

Check the width and height of weld: the size of weld should meet the design requirements, and the consistency of width and height is good, otherwise there may be unstable welding or poor sealing.

Second, the pressure test

Pressure test is a commonly used method to test the tightness.

Hydrostatic test: Fill the stainless steel air duct with water of a certain pressure and keep it for a period of time to observe whether there is water leakage. This method is suitable for some air duct systems with high sealing requirements.

Operating steps: seal all the openings of the air duct, connect the hydraulic pump, and slowly increase the pressure to the specified pressure. Generally, the pressure value is determined according to the service requirements and design standards of the air duct. Keep the pressure for a period of time, usually 15 to 30 minutes, and observe whether there is water dripping or pressure drop on the surface of the air duct.

Precautions: Before carrying out the water pressure test, make sure that the strength of the air duct can withstand the test pressure, so as to avoid the rupture of the air duct due to excessive pressure. At the same time, it is necessary to check whether the sealing part is well sealed to prevent the illusion of water leakage during the test.

Air pressure test: Fill the air duct with gas with a certain pressure, such as compressed air, and then use leak detection liquid or other detection methods to check whether there is air leakage.

Operation steps: close the inlet and outlet of the air duct, and fill the air duct with gas through the inflator, and gradually increase the pressure to the specified value. Soap bubbles, leak detection liquid, etc. can be applied to welds and joints to observe whether there are bubbles to determine whether there are air leakage points.

sonic testing needs professional equipment and technicians, and the operation should be carried out in the right way to ensure the accuracy of the test results.