Manufacturing And Inspection Of Spiral Plate Heat Exchangers

Manufacturing Process of Spiral Plate Heat Exchanger:

Material preparation, assembly – non-destructive testing – flanging, contact welding of spacer columns – surface cleaning – final assembly – non-destructive testing – rolling – channel shaping, channel welding, assembly – machining – assembly – pressure testing – pickling and passivation, painting – packaging.

End cap material preparation (profile cutting) – assembly (circular ribs, inverted cone) – bonding of composite plates – non-destructive testing – machining – leak detection – post-treatment – ​​painting.

Quality Control in Spiral Plate Heat Exchanger Manufacturing:
The curvature of the spiral plate should be less than 3mm per meter.

For spacer column welding, both manual welding and contact welding methods are used. The quality of spot welding of manually welded spacer columns should be inspected. If burn-through or missed welds are found, in addition to re-welding, the spot weld quality should be 100% inspected. Controlling the length of the spot weld ensures that the spacer columns do not fall off during spiral rolling. Care should be taken to avoid surface biting during arc initiation and termination.

Because the smaller the rolling radius during the rolling process of the flanged spiral plate, the greater the elasticity of the flange, the end edge (flange) of the spiral channel should be corrected and shaped after rolling.

For detachable spiral plate heat exchangers, the end face sealing surface should be machined only after the spiral body and narrow-edge flange are assembled and welded. The lower end face of the narrow-edge flange and the sealing surface must be kept horizontal; otherwise, when the upper clamp is tightened, the lower clamp will generate additional bending moment.

During pressure testing, a grid-like fixture must be used for detachable spiral plate heat exchangers to prevent axial deformation. During the test, compressed air is introduced into one channel, and water is placed in the other channel, or the equipment is submerged in water. Checking the welding quality ensures that there is no internal leakage between the two media. For products that cannot undergo hydrostatic testing, a pneumatic pressure test is required. During the test, compressed air is introduced into one side, and the other channel is sealed. A hose is inserted into the water to check for potential internal leaks.