Key points for using graphite crucibles, online explanation from a corundum crucible manufacturer

  Corundum crucible The manufacturer believes Cleaning the graphite crucible Preliminary The initial step is to clean the chemicals from inside the crucible before proceeding with the cleaning process. The cleaning method depends on the residue in the graphite crucible. The deposits on the graphite crucible are usually inorganic combustion residues. Hydrochloric acid can be used for cleaning, as it dissolves most residues. Some carbon-containing residues are insoluble in hydrochloric acid. In this case, nitric acid can be used due to its strong oxidizing properties; heating may be necessary during cleaning.

　　 Corundum crucible The manufacturer believes Substantially stubborn residues can be boiled in dilute hydrochloric acid or dilute nitric acid. Note that the hydrochloric acid used must not contain oxidizing agents such as nitric acid, nitrates, or halogens. If dilute nitric acid is ineffective, use potassium pyrosulfate, sodium carbonate, or borax for fusion cleaning. Graphite crucibles must be kept clean and bright inside and out. After prolonged combustion, the exterior of the crucible may darken. Over time, this darkening can penetrate the interior, making the crucible brittle and prone to breakage. Therefore, it is necessary to remove impurities. If stains or blackening persist on the surface, use fine sand without sharp edges, sifted through a 100-mesh sieve, and gently wipe with water to restore the surface luster. Use fine sand (100 mesh) and water to gently wipe the crucible, restoring its surface shine.

　　 Corundum crucible The manufacturer believes Precautions for using graphite crucibles:

　　1. Store the crucible in a well-ventilated and dry environment to prevent moisture damage.

　　2. Handle the crucible with care. Avoid dropping or rolling to prevent damage to the protective layer on the crucible surface.

　　3. Before use, pre-bake the crucible. Increase the baking temperature slowly from low to high, constantly turning the crucible for even heating to remove moisture. Gradually increase the preheating temperature to above 500°C (if improper preheating causes the crucible to peel or burst, it is not a quality issue and will not be returned).

　　4. Corundum crucible The manufacturer believes The crucible furnace should match the crucible; gaps above, below, and around should meet requirements. The furnace lid should not press on the crucible body.

　　4. During use, avoid directing the flame directly into the crucible body; direct it towards the crucible base.

　　6 Corundum crucible The manufacturer believes When loading the furnace, do not tilt. The top should not be higher than the furnace opening; use support bricks along the furnace wall.

　　6. When adding materials, add them slowly and in small pieces. Do not overfill or pack the crucible too tightly to prevent cracking.

　　7. The crucible tongs used for loading and unloading should match the crucible's exterior to avoid pinching the crucible.

　　8. Use the crucible continuously to fully utilize its high performance.

　　10. Corundum crucible The manufacturer believes The amount of additive added during smelting. Excessive use will reduce the crucible's service life.

　　1 9. When using the crucible, rotate it regularly for even heating and extended service life.

　　11. Cleaning Corundum crucible The manufacturer believes that cleaning When removing slag and coke adhering to the inner and outer walls of the crucible, gently tap to avoid damaging the crucible.