{"id":277,"date":"2024-10-08T17:30:08","date_gmt":"2024-10-08T09:30:08","guid":{"rendered":"http:\/\/www.1.com\/?p=274"},"modified":"2025-03-21T18:44:56","modified_gmt":"2025-03-21T10:44:56","slug":"about-detail-16","status":"publish","type":"post","link":"https:\/\/www.hexinmusu.com\/en\/about-detail-16.html","title":{"rendered":"Sand casting process"},"content":{"rendered":"

What is sand casting?<\/h2>\n\n\n\n

Sand casting , also known as sand casting, is a time-honored method of casting process with a wide range of applications across the globe. The process of producing castings by using clay bonded sand (or other materials such as gypsum, silicone, etc. made of sand) as the modeling material. The principle is to take advantage of the softness and ease of molding of the sand mold by pouring molten metal into the sand mold, and then crushing the sand mold after the metal has solidified in order to obtain the desired casting. Applied in a variety of metals, common aluminum sand casting, iron sand casting, copper sand casting, and now let the aluminum alloy casting factory in chinaNingbo Hexin<\/a>The sand casting process is explained in detail.<\/p>\n\n\n\n

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Sand casting production conventional process flow<\/h2>\n\n\n\n
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Sand casting process<\/strong><\/h2>\n\n\n\n
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(1) Preparation of molding sand and core sand<\/strong><\/h3>\n\n\n\n

The molding materials used for sand casting are mainly sand used for making sand mold and core sand used for making sand core. Usually the sand is made of raw sand (mountain sand or river sand), clay and water mixed in a certain proportion, of which clay is about 9%, water is about 6%, the rest is raw sand. Sometimes a small amount of additives such as coal powder, vegetable oil, wood chips, etc. are added to improve the performance of the sand and core sand. The structure of the compacted sand is shown in the figure.<\/p>\n<\/div>\n\n\n\n

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Schematic diagram of sand structure 1 - sand grains 2 - voids
3-Addition 4-Clay membrane<\/p>\n<\/div>\n<\/div>\n\n\n\n

Core sand is generally prepared by hand due to its low demand.
The environment in which the core is harsh, so the core sand performance requirements than the high sand, while the core sand binder (clay, oil, etc.) than the binder in the sand in the ratio of the importance of some of the larger, so its permeability is not as good as the sand, the core should be made to make a breathable channel (holes); in order to improve the concessions of the core to be added to add additives, such as wood shavings.
Some demanding small castings tend to use oil sand core (tung oil + sand, baked until yellow-brown and become).<\/p>\n\n\n\n

(2) Properties of molding sand<\/strong><\/h3>\n\n\n\n

The quality of sand directly affects the quality of castings, poor sand quality will make sand casting products produce porosity, trachoma, sticky sand, sand and other defects. Good sand should have the following properties:<\/p>\n\n\n\n