What are the requirements for the selection and purchase of electric heating tubes by the heater manufacturers of the air duct?

When working in the mold heating tube tube single end electric heating and temperature control is crucial, once the temperature is out of control, will lead to the pipe body, black oxidation, deformation of external stainless steel tube, resulting in internal heating element electrothermal alloy wire for high temperature air burning fuse, which itself shortens the service life of single end electric heating tube the general control for 200-300 degrees in between. Finally, in the electric heating tube, is to consider the motion of the working environment, design and production of mold in single tube before the end of the electric heating, we also need to consider the motion of the working environment, if the vibration is relatively large, the electric heating tube in heating wire requires the use of nichrome wire.

The most popular immersed flange type electric heating pipe is widely used in industry. Besides, the single ended electric heating tube is widely used. But if it is used carelessly, it may be easily damaged. What causes the single ended electric heating tube to be damaged easily?

On the one hand, the electric heating tube mould and die hole diameter of single end electrothermal tube density during use, the need to pay attention to, because the single end electric heating tube rapid cooling condition is poor, often caused by the body, black oxidation, deformation heating external stainless steel tube, resulting in internal heating element electric wires for high temperature air burning fuse. That shorten the life of single end electric heating tube;

On the other hand, there is a need for reasonable control over the working temperature.

First you have to understand the resistance of it: components should bear 1000 cycles of heat resistance test in the test conditions specified and test voltage, without being damaged; in the test voltage and temperature rise test components from the environment temperature and time should be no more than 15min; there is a deviation in the full rated power: fever under the condition that the deviation of the components of the power rating should not exceed the scope of the following provisions; the rated power is less than or equal to 100W components: + 10%. The rated power is more than 100W of components for +5% ~ -10% or 10W, whichever is larger; the insulation resistance is also very important parts: the factory inspection of cold insulation resistance should not be less than 50M, seal test, insulation resistance after long-term storage or use should not disappear and M, thermal insulation the operating temperature of the resistance should not be less than the value in the formula, but the minimum should be no less than 1M ohm; finally the insulation strength: elements should be 1min in the specified test conditions and test voltage, and no flashover and breakdown phenomena and so on.

The electric heating pipe is divided into two types.

1. Heating air

The working temperature is about 200-300 degrees, and the stainless steel 304 is used.

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

The working temperature is about 600-700 degrees, and the material of stainless steel 310S is used.

Working temperature 800-900 degrees, use yinggelai material.

Two. Heating liquid

Tap water: stainless steel 304 material; heating drinking water to use food grade 316 material, more easily fouling water with waterproof scale coating.

Oil: stainless steel 304 material or iron material.

Heating weak acid and alkaline liquid: corrosion resistant stainless steel 316L material.

Strong acid and strong alkaline liquid: reference liquid electric heater selection table.