1. Visual inspection The metal tube of the electric heating tube shall not have obvious mechanical scars or local expansion, and there shall be no wrinkles, bumps and other phenomena at the bend. The coating, electroplating layer, metal or non-metal spray coating, and aluminized layer should be uniform and firm. There should be bubbles, peeling or local accumulation, etc. Electric heating tube size deviation check electric heating tube length deviation check (for the above deviation check, please refer to: Analysis of Electric Heating Tube Industry Standards | Regulations on Electric Heating Tube Deviation)
2. Hydrostatic test (heating pipe suitable for heating liquid) The components used to heat liquid and the joints installed below the liquid level should be able to withstand a hydrostatic pressure test of 0.5Mpa for 5 minutes without leakage. Components with a pressure of more than 0.1Mpa must be subjected to a water pressure test for 30min. There should be no leakage, no visible deformation or deformation affecting performance. The test pressure should be greater than or equal to 1.25 times the design pressure, and no Below 0.5Mpa.
3. Cold state insulation resistance measurement The cold state insulation resistance value should not be less than 50MΩ during the factory inspection.
4. Cold-state insulation withstand voltage test According to the requirements of the customer to test the withstand voltage, there is no flashover and breakdown in 1min. The normal insulation withstand voltage is 1300V, 1600V withstand voltage, and the high-demand insulation withstand voltage is 2400V, etc.
5. Rated power measurement Generally, the rated power is measured, and we will judge it by measuring the cold resistance.
