Structure and application characteristics of carbon tube furnace

The carbon tube furnace is a furnace type (W + C → WC) which mixes tungsten powder (or other metal powder that needs to be carbonized) with carbon black in a certain proportion and generates tungsten carbide (or other carbides) at high temperature in the carbon tube. The equipment is mainly used for carbonization of metal powder, double carbonization and reduction of the original, and the furnace temperature can reach 2200 at most. It has the advantages of simple structure, fast heating speed and high working temperature. It can be used for carbonization of various fine, medium and coarse particles to prepare carbides.

Structure of carbon tube furnace:

The carbon tube furnace is a vertical vacuum electric furnace, which is composed of furnace cover, furnace body, furnace bottom and vacuum unit. The inner layer of furnace shell is stainless steel, the outer layer is carbon steel, and the two layers are cooled by water. The furnace shell is equipped with air extraction port, observation hole, thermocouple hole, protection atmosphere inlet and outlet, explosion-proof port, etc. The furnace is equipped with graphite electrode, which is connected with graphite heater by cylindrical contact. One end of the electrode extends out of the furnace through sealing. It is an important part to make the current channel through the heater. A heat insulation screen device composed of multi-layer radiation screens is arranged around the heat generator.

Main features of carbon tube furnace:

1. If the material is in the boat dish, there will be no secondary pollution.

2. The inner tank and flange of the furnace body are made of stainless steel, which is not rusty and has a long service life.

3. Equipped with vacuum pump to replace the gas in the furnace, the gas exchange time is short and the gas consumption is small.

4. The furnace body has good sealing performance and small loss of protective gas. All flanges and furnace covers are sealed with sealing strips.

5. The temperature of Zui can reach 3000 ℃, and it can work in 2600-2800 ℃ for a long time.

6. Adopt automatic feeding device, time control in and out of material, high degree of automation, low labor intensity of workers, consistent high temperature processing time of products.

7. Carbon felt is used as thermal insulation material, no carbon black is used, it is convenient to replace carbon pipe, and it is clean and sanitary at the same time.

8. With infrared temperature measurement and control system, it can display and PID automatically control the temperature in the furnace in real time, and the product quality is stable. At the same time, guarantee the product requirements.

9. Using electromagnetic heating method, the carbon tube in the furnace is heated by electromagnetic induction, the efficiency is higher than that of short-circuit heating of carbon tube, the temperature uniformity is better, the constant temperature zone is longer, and the equipment operation failure rate is low.

10. Adopt three-phase power supply mode, three-phase power balance, stable performance. Unlike the carbon tube furnace, which uses single-phase power supply, the phase voltage is unbalanced, which has a great impact on the power grid and affects the operation of other equipment.

11. The continuous production without stopping the furnace can be realized by pushing boat. Unlike the gap type (vertical furnace), the furnace is not shut down every time it is burned, and the material can be taken out only after it is cooled. The production efficiency is low and the energy consumption is high.

12. The product quantity of each boat is about 1.5kg, which can be sampled in time to track and test the product quality, and the process can be modified according to the test results, without stopping the furnace, the waste of materials is also less.

13. Long service life, continuous production for 20-30 days without furnace shutdown. In the ordinary carbon tube furnace, if the carbon tube is burnt at one point, its radial position will rapidly increase the burnt furnace tube, and the diameter will become smaller, which will cause the carbon tube to burn out and cannot be used. In electromagnetic induction heating, when one point is burnt out and the diameter becomes smaller after burning, the heating temperature will not rise, but will relatively reduce until it reaches balance with other parts. Because its service life is much longer than that of carbon tube furnace.