Graphite rod is a non-metallic product made of carbon, graphite and suitable binder, which is formed by extrusion. Graphite rods have the advantages of more stable chemical properties, energy saving and environmental protection, and can resist the corrosion of acids, alkalis and organic solvents. So what is it good for? What should we pay attention to when using graphite rods?
1. Used in chemical industry: In order to ensure the safety of chemical products in the manufacturing process, graphite rods can play a role in isolating flames. Because it generates volume under heat, and then expands rapidly, resulting in the phenomenon of smothering flames.
2. Pyrometallurgy: In order to save more metal, we usually use graphite rods as the mold for glassware, which is conducive to making the size of the manufactured castings more accurate.
3. Wear-resistant and smooth: Generally, it can be used as a piston cup in equipment that transports corrosive media. In the machinery industry, if only lubricating oil is used, the product cannot achieve good results under high speed, high temperature and other conditions. By using graphite rods, it is beneficial to make it slide quickly at relatively high temperatures.
4. Use as refractory: We use graphite rods in steelmaking, which are called protective agents, which are metallurgical linings.
1. Red heat uniformity: During the process of using it, the red heat uniformity of the bar will gradually decrease, and when a serious situation occurs, the bar will be broken. Therefore, we need to choose graphite rods for heating parts with good red heat uniformity.
2. The temperature is too high: it shortens with the increase of the use temperature, and the oxidation speed also increases with the increase of the temperature. For example: when the temperature exceeds 1500 ℃, the oxidation rate is accelerated and the life is shortened. Therefore, we need to pay attention to controlling the temperature of the graphite rod surface when using it.
3. Silicon oxide film: when it is heated in the air, it will form a film that prolongs its life (dense and anti-oxidative silicon oxide film). However, if we do not use it continuously, with the rise and fall of the kiln temperature, the maintenance film on the surface of the bar will rupture, which will weaken the maintenance effect and accelerate the increase of the bar resistance value. In order to meet the needs of rapid temperature rise and ensure the stability of the furnace temperature, the supporting electronic control system needs to reserve enough voltage adjustment margin. Depending on the pressure adjustment method and wiring method, the upper limit of the later voltage is generally 220V or 380V as the calculated value. Voltage residual value: the voltage of the graphite rod in the later period of use is generally 1.5-1.7 times the voltage of the new rod.