Pipe Shrinking in the production process of electric tubular heaters:
In order to increase the density of the filler in the heating tube and increase the thermal conductivity of the filler without reducing the insulation resistance, the diameter of the tube must be compressed after the powder is filled, that is, the "Pipe shrink"
Purpose of pipe shrinking:
The purpose of pipe shrinking is to use the method of reducing the pipe diameter to make the filling density of the tubular heaters reach about 3.5g/cm3. Therefore, the technical requirements for the use of electric tubular heaters can be applied.
Common methods of pipe shrinking:
1. Use a pipe-drawing machine to draw thin;
2. Compress with a rotary forging hammer;
3. Reduce diameter with tie rollers.
It is worth noting that no matter which method is used, the parameters will change during the pipe diameter compression process, that is, as the pipe diameter decreases, the pipe length will extend, and the resistance value of the spiral wire in the electric tubular heaters will also be changed. These changes of parameters must be mastered by engineer, otherwise it will not be able to produce qualified electric heating tube products.