How to verify the quality of the flange heating tube

- Jul 22, 2019-

The most intuitive way to verify the quality of the electric heating tube is to clean the surface of the electric heating tube, then turn on the AC 220V power supply, dry it in the air, turn off the surface after the red light, and wait until the electric heating tube is completely cooled. Wipe, there should be no black oxidized powder on the white paper (not reacted with oxygen in the air), which is described as a high quality electric heating tube.


1. Power input test rated input power (W): power is applied at rated voltage, and its power deviation cannot exceed the following table.


Rated input power (W)


Deviation


deviation


W≦200


±10%


W>200


Positive deviation: +5% or 2


Negative deviation: -10%


2. Electrical strength test:


a. Electric strength in cold state: It should be able to withstand 50Hz, 1min withstand voltage, cut off current 5mA, no breakdown, flashover phenomenon.


Rated voltage test voltage


250V 1250V


b. Electrical strength at working temperature: withstand 50Hz, 1min withstand voltage, cut off current 5mA, no breakdown, flashover phenomenon.


Rated voltage test voltage

250V 1000V


3. Leakage current at operating temperature


The electric heating tube is input at a rated power of 1.15 times under a fully exothermic condition, and the leakage current is 0.5 m A.


4, overload test


The electric heating tube is energized for 1 hrs at 1.27 times of rated power under full heat release conditions, and is cooled down to 0.5 hrs to room temperature (forced cooling is allowed), so that 30 cycles are repeated without damage.

5, electric heating tube shell sealing test (tube crack test)


Immerse the electric heating tube in acidified water (2%~3% hydrochloric acid, sulfuric acid or nitric acid) for 3hrs. The two ends of the electric heating tube should be exposed to at least 5mm, and the performance requirements of the second to third items should be met after the test.


6, sealing seal test


Place the electric heating tube in an environment with a temperature of 60 ° C and a humidity of 95% for 24 hrs. After placing it, it should meet the performance requirements of items 2 to 3.


7, life test


The electric heating tube is energized at a rated voltage for 1 hrs under full heat release conditions, and is cooled down to 0.5 hrs to room temperature (forced cooling is allowed), and the accumulated working time is 3000 hrs.