Using electricity as a heat source, the electrical energy is transformed into heat energy to heat the workpiece by various methods. When electric heating, the temperature is easy to control, no environmental pollution, high thermal efficiency. There are several ways of electric heating.
1, thread spiral surround electric radiant tube This kind of electrothermal radiant tube is composed of heat-resisting alloy steel casing and heater, the heater is generally made of φ3-5 mm electrothermal wire around the heat insulating ceramic tube core with spiral groove, working voltage 220V, power general 5-7kw.
2. The structure of this heater is basically the same as that of the first structure, only the heating element uses the resistor belt to revolve, the resistance belt general thickness is $number mm, the width $number mm, the tube core also is many group type tube core composition, under the same surface load, the heat radiant surface is big, the material can save, The general high-power point heating radiation tube used in this form.
3, the axial twists and turns the cage type Electric radiant tube (commonly known as the Squirrel Cage) its structure is the heating elements of the resistance wire (belt) curved into "U"-shaped string into a number of insulated ceramic support plate, high temperature the middle is fixed with a heat-resisting rod, generally effective length: 900~2400; general casing outside diameter: φ80~φ280. Single power: 2kw~40kw; one-root voltage: 30v~220v. This radiation tube has a long life.
Characteristics of electrically heated radiant tubes
1. Practical and reliable. I plant products to the user after production verification, reliable and durable quality.
2, the core materials using DC Argon arc welding, so that the surface load, resistance and other technical indicators are guaranteed.
3, heat-resistant insulating material is a German formula, the porcelain pieces of good thermal shock resistance, high temperature, long life, good surface quality. The company designed and manufactured electric radiant tube, with high, medium and low temperature furnaces and special atmosphere furnace specifications optional. The outer casing system adopts seamless high-temperature alloy tube and coil tube, centrifugal cast pipe, nonmetal special-purpose anti carburizing casing, etc. and the general resistance alloy can not be applied under the condition that the radiant tube heating element is used under various atmospheres and bad cyclic conditions. The company's researchers developed a new special material for the resistance alloy radiation tube. The material has stable performance, high resistivity and low temperature coefficient, and is suitable for use in various radiant tube heating elements, which replaces the expensive imported material with unique performance.
The advantages of electric radiant tube are
1, installation, testing, maintenance convenience, are carried out outside the furnace. Replace the electric heating device without stopping or cooling the furnace temperature. Under normal production conditions, the replacement only takes about 10 minutes, greatly reduces the labor intensity, enhances the productivity.
2. Compact structure, stable performance, large single power and service life are several times of ordinary electric heating pipe.