1. The design of the heating pipe should consider the effects of thermal expansion and contraction, ablation, oxidation, creep, etc., so as to avoid failure due to deformation during normal operation.
2. The internal structure of the heating tube shall be designed to ensure that the maximum temperature of the material used for the heating tube is not damaged or the highest temperature that may be encountered during processing, and it can still work reliably.
3. The welding structure design of the heating pipe should conform to the relevant standards. The welding seam of the pressurized heating pipe, especially the part inside the container, should be as few as possible, and the setting of the weld should be easy to check.
4. The design of the heating tube casing and its accessories subjected to pressure must comply with the relevant standards.
5. The heating tube (including the end) must be sealed.
6. The heating pipe used for the heating of the aggressive medium must use a corrosion-resistant metal pipe or a protective cover to ensure the working life of the heating pipe.
7. When the outer casing of the heating pipe is ordinary steel or other alloy materials with better performance than ordinary steel, the wall thickness should be not less than 0.35mm. When the outer casing is made of copper or copper alloy, it must be based on the corresponding mechanical strength. Adapt to the harsh working environment.
8. The bending radius of the heating pipe should not be less than 2.5 times the diameter of the heating pipe.
9. The curved shape of the heating tube must ensure that the inner end of the extraction rod is on the straight part of the tube, and the distance from the starting point of the bending should be not less than 10 mm.
10. The distance between the two intercepting portions of the heating tube with a potential difference greater than 40V and the gap between the intercepting portion and the outer casing and the thickness of the insulating filler shall be not less than 1 mm, and the distance between the exposed lead wire and the outer casing shall be not less than 1 mm. (Note: If there is an agreement, the above clearance and distance can be less than 1mm, but the design needs to be strengthened and carefully manufactured to ensure performance and reliability)
11. The cross-sectional area of the heating pipe lead-out wire should not be less than 7 times the cross-sectional area of the heating wire.