What are the reasons for the damage of the mold heating tube?

1. Power design

The power of the ordinary mold heating tube cannot be too large, and the normal surface load cannot exceed 8w/cm2. The surface load of the imported heating tube is 11-12w/cm2. The greater the surface load of the standard mold heating tube, the shorter the life.

 

2. Material selection

The mold heating tube belongs to the scope, so its working environment and working temperature are different and the material selected will be different.

The working temperature is about 100-300 degrees, and the heating tube is made of stainless steel 304.

The working temperature is about 400-500 degrees, and stainless steel 321 can be used.

The working temperature is around 600-700 degrees, so stainless steel 310S should be used.

Therefore, the material is not selected correctly, which is also the reason for the short life. And whether the mold is vibrating, if it is vibrating, use nickel-chromium wire with better flexibility.

Three, the gap between the mold hole

 

Because air is an obstacle to heat conduction, the heat cannot be dissipated, which will cause the surface temperature of the heating tube to rise, causing the internal temperature of the heating tube to rise. When the internal temperature of the mold heating tube is high to a certain extent, it will burn Bad resistance wire will shorten the life of the heating tube of the mold, and even more serious tube bursting will occur, so the gap between the heating tube and the mold should not be too large. However, the gap between them cannot be too small, because the mold heating tube will expand due to the principle of thermal expansion and contraction after being installed and energized. Many molds cannot be taken out when the heating tube is broken.