a. Sand consumption
The distance between the impeller investment casting sand casting pattern and the inner wall and top of the sand box is called the sand consumption. In order to prevent fire escape and mold leakage during the impeller investment casting sand casting pouring, the appropriate sand consumption should be selected. In the actual impeller investment casting sand casting molding process, 50mm ~ 100mm is selected. The upper and lower molds are made of chromite sodium silicate sand as surface sand. The thickness of surface sand is 20mm ~ 25mm, and most of the thickness is 30mm ~ 35mm.
b. Calculation of lifting force and weight
K – safety factor in the formula, generally 1.2 ~ 1.5.
Then the formula:
Therefore, the tightening force of impeller investment casting sand casting mold is 10.56 × 103N。
The upper and lower shapes shall be fastened by pressing iron.