When purchasing high power graphite electrodes, you must do a good job of quality inspection. Even in the acceptance check, there should be no slack. The surface of the high power graphite electrode generally does not contain more than two pieces or two holes, and no holes or cracks are allowed on the joints, joint holes, and electrode surfaces within 100mm from the bottom of the hole. The thread length of the joint and joint hole shall not exceed 30mm. The surface of high power graphite electrode is not allowed to have transverse cracks. In terms of longitudinal cracks with a width of 0.3 to 1.0mm, the length of the cracks should not be greater than 5% of the electrode circumference, and no more than two are allowed; the number of longitudinal cracks with a width of less than 0.3mm are not allowed to exceed 2. For the surface area of a high power graphite electrode, its width is less than one-tenth of the electrode circumference, and its length is less than one-third of the electrode length. And there are different types of graphite electrodes. In order to ensure the quality of high power graphite electrodes, in addition to the above details, it is necessary to pay attention to packaging, marking, storage, transportation and quality certificates.
The lower the electrical resistivity of the graphite electrode for sale, the higher the thermal conductivity and the better the oxidation resistance. The current density of the graphite electrode is related to its electrical resistivity and electrode diameter. The lower the electrical resistivity of the graphite electrode, the higher the permissible current density; the larger the diameter, the smaller the density.
The mechanical strength of high power graphite electrodes can be divided into compressive strength, bending strength and tensile strength. The flexural strength is a performance index related to the fracture of the graphite electrode during use. In the electric furnace, when the electrode is in contact with a non-conductor, or due to collapse, collision, strong crack vibration damage, effects, etc., the graphite electrode is often in danger of being broken. The graphite electrode has high bending strength and is not easy to break. When multiple electrodes are connected in series on the electrode column, the connection is subject to a lot of tension, so the tensile strength index of the joint should be specified.