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JINDI JIXIE

Jindi machinery co., LTD    —

What is core sand classification

According to the different binder used in the core sand into clay core sand, sodium silicate core sand, sand wick, lipid core sand, resin sand core, etc. Shape simple core, generally available clay core sand is made; Complicated shape, cross section is fine thin, require high dry strength and good breakup sex cores, core sand is used vegetable oil, lipid core sand and resin sand core.

Plant oil sands core is very bright and clean castings can be obtained, but the tung oil, linseed oil, used modified rice bran oil, such as supply, less expensive.

Therefore, widely used in China since 1963 after soap industry producing synthetic fatty acid residue (referred to as fat) as a binder.

The core sand with approximate oil dry strength of core sand, concessions and melting away. Use oil core sand and lipid core sand making sand core, hardened before core strength is quite low, easy to deformation, slow hardening, long production cycle, need drying, etc., affect the casting dimension accuracy and production efficiency.

Resin was used as core sand binder, including: self-hardening resin sand core, ester hardening sodium silicate core sand and core sand (shell) of precoated sand core sand, hot core box core sand and core sand of cold box cores.

Small batch casting production can use the hard core sand binder, sand hot core box core should be adopted for the casting production in large quantities, the core sand of cold box cores, special requirements can use of precoated sand core sand castings.

The core of legal system of cold box cores in the factory of mass production of automobiles, tractors and get a wide range of applications.