Cause Analysis and Correction Methods for Poor High Voltage Resistance of Electric Heating Tubes

In the daily production and operation process, many customers and industry practitioners often inquire about the reasons for high voltage resistance test failures of electric heating tubes and how to avoid such unqualified products. Today

(Right-angle type heating tube)

1. Unqualified quality of magnesium oxide powder used for heating tubes

Solutions:

•Select magnesium oxide powder with high magnesium content and low impurity content;

•Strictly control the operating temperature of heating tubes during actual operation;

•Guarantee the qualified thickness of the insulating layer of electric heating tubes;

•Keep the heating tube shell clean and ensure the full dryness of magnesium oxide powder.

2. Excessive impurity deposition at the lower end of heating tubes during powder filling

Solutions:

•Thoroughly clean the inner diameter of the heating tube shell;

•Maintain the cleanliness and tidiness of the powder filling machine at all times.

3. Poor sealing and air bubbles existing at the sealing end of heating tubes

Solutions:

•Optimize the sealing process of electric heating tubes;

•Replace high-quality sealing materials.

4. Eccentricity of the resistance wire inside electric heating tubes

Solutions:

•Standardize the speed and quality of the powder filling process;

•Operate the tube shrinking process in strict accordance with technical specifications.

5. Cracks generated during the welding process of heating tubes

Solutions:

•Improve the welding process level;

•Strengthen full-process inspection and quality monitoring of welding procedures.

6. Blackening of magnesium oxide powder during heating operation

Solutions:

Prevent chromium precipitation by optimizing material selection; avoid using iron-chromium-aluminum resistance wires for electric heating tubes.

7. Residual impurities and metal scraps at the tube opening

Solutions:

Thoroughly clean the tube opening of every single heating tube before delivery.

8. Rust on lead-out rods or residual welding slag at the tube opening

Solutions:

Perform rust removal and polishing treatment after welding, and conduct thorough cleaning of the tube opening.

9. Insufficient dryness of heating tubes before factory delivery

Solutions:

Extend the drying time sufficiently to ensure the complete dryness of electric heating tubes.