What should I do if the casting sticks to the sand? Hongzhe Hardware Casting tells you the right way

Sometimes byAlloy steel precision castingfactoryThe surface of the produced casting is covered with a layer of impurities, usually a mixture of metal or sand, which makes the surface rough and difficult to remove. If impurities exist on the surface of the casting, it means that the casting has sand sticking.

So how to preventendAlloy steel precision castingWhat about sand casting? First, appropriately lower the pouring temperature and increase the pouring speed, which can reduce the chemical reaction caused by the thermodynamics and physical operations of light sand;Repair the molding sand and core without local shrinkage. The coating should be a coating that does not crack at high temperature, which can greatly guaranteeAlloy steel precision castingThe quality of the casting.

1. The following countermeasures can be used to prevent slag inclusion in mechanical equipment

1) Prevent high metal hydrostatic pressure head; take into account the metal mold casting standard of castings, the height-to-width ratio of the riser does not need to be too high; prevent the ladle from being in the upper position and directly drenching in the sprue, and basin-shaped pouring can be used when needed. The cup buffers the metal flow and generates a constant high static pressure head.

2) Use foundry sand with finer particle size distribution as much as possible.

3) The sand mold should be compact and fine. The design of the equipment should not be overweight and provideAlloy steel precision castingThe air compression of the casting moulding machine should maintain the required pressure to prevent the application of moulding sand that is too wet or the storage period is too long. Because it cannot be compacted, the core box vent (plug) should not be blocked; resin sand moulding design and core making should not be Relying on the excellent circulation of molding sand, it is necessary to ensure firmness and vibration when necessary.

4) Avoid mold "explosion" or "choking". Do not add too much pulverized coal and water to the molding sand. Make vent holes and vent holes for the mold and core as much as possible to improve the breathability of the mold.

5) Relieve the dynamic pressure caused by the model. The mold should be provided with more vent holes and more air holes; the analysis surface of the mold with high compactness can be provided with an exhaust pipe groove (ventilation groove or ventilating groove).

6)Alloy steel precision castingAppropriate coating should be applied to the mold or core. That is, the gap between the sand particles on the top surface of the filling type and the core. If the paint is too thick, it is likely to crack and allow the molten metal to penetrate into the sand. At this time, apply a thinner paint in the first or second layer, and thenConventional or thicker paint.