What are the commonly used manual molding methods used in casting?
4. a part of a mold, such as a boss or bar, that prevents the die from being formed, and the movable block and the shape body can be detachably connected by a pin or dovetail structure. When the die starts, the shape body is taken out first, and the movable block die is left in the mold. After the die is taken out, the molding method of the movable block is taken from the side, called the movable block mold. The movable block mold is mainly used for the casting with prominent parts, which prevents the die casting, single piece, small batch and manual molding. If such castings are in large quantities and require machine molding, they may be formed with sand cores to prevent the part of the mold being drawn. 5. dig sand molding casting when the external contour surface (such as wheel etc.) the maximum section is not at the end, and the like should not be divided into two halves, should be looked as a whole, the sand molding dug out when removing hinder look, this modeling method called digging sand molding. The parting surface of sand excavation is curved surface, and the sand must be dug to the maximum section of the shape in order to ensure the smooth molding. As a result of manual sand digging, the operation technology requirements are high, and the production efficiency is low. It is only suitable for single and small batch production.
Two box molding is widely used in the casting of complex shapes, such as water pipes, bushings, valves and other porous castings. 3., three box molding, casting shape for both ends of the large section, the middle section of small, such as pulley, groove wheel, lathe, square knife holder, etc., in order to ensure the smooth lifting of the mold, should use three box molding. The parting surface should be in the minimum cross section shape, and the parting surface is still in the largest section at both ends of the casting, the three box shape has two parting surface, reducing the dimensional accuracy of height direction of the casting, cleaning workload has increased the parting surfaces at the burr, the operation is complex, low productivity, does not apply to other machines, therefore, three cases of other complex shape, not only for the other two casting box.
Because of its flexible operation, simple process equipment, strong adaptability and no modeling equipment, hand molding is widely used in single piece and small batch production. But manual molding productivity is low, labor intensity is bigger. Commonly used manual molding methods have the following: 1., the whole mold for the simple shape, the end of the plane and the largest cross-section of the casting, should use the whole mold modeling. The whole mold is easy to operate, and the shape of the whole shape is placed in a sand box without any box defects. The whole model is suitable for simple shape, the maximum section at the end, and the plane of the casting, such as the maximum section of gear blanks, bearing seat, cover and shell mould casting 2. points when not at the end of casting, in order to shape and mould to look into two halves or parts of this. Other is called modeling. When the maximum cross section of the casting is in the middle of the casting, the two cases should be modeled separately, and the shape shall be divided into two halves from the maximum cross section (pin positioning). When molding, the patterns are respectively placed in the upper and lower sand boxes, and the parting surfaces (the joint surfaces between the shape and the pattern) coincide with the positions of the parting surfaces (the joint surfaces between the sand molds and the sand molds).
