大型机床铸件的铸造工艺详细介绍
时间：2015/12/30 10:07:36
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大型机床铸件主要是用于机床的平板制造，简单接受一下铸造工艺。
低压铸造是使液体金属在压力作用下完成充填型腔及凝固过程二获得铸件的一种铸造方法。由于所用的压力较低（20~60kPa），所以叫做低压铸造。其工艺过程是：在密封的坩埚（或密封罐）中，通入干燥的压缩空气，金属液在气体压力的作用下，沿升液管进入直浇道3上升，通过内浇道2平稳地进入型腔1，并保持坩埚内液面上的气体压力，一直到铸件完全凝固为止。然后解除液面上的气体压力，使升液管中未凝固的金属液流回坩埚，再开型并取出铸件。低压铸造过程的基本特点：充填速度、压力可适当调整。
低压铸造所用的铸型，有金属型和非金属型两类。金属型多用于大批、大量生产的有色金属铸件，非金属铸型多用于单件小批量生产如砂型、石墨型、陶瓷型和熔模型壳等都可用于低压铸造，而生产中采用较多的还是砂型。但低压铸造用砂型的造型材料的透气性和强度应比重力浇注时高，型腔中的气体，全靠排气道和砂粒孔隙排出。为充分利用低压铸造时液体金属在压力作用下自下而上地补缩铸件，在进行工艺设计时，应考虑使铸件远离浇口的部位先凝固，让浇口最后凝固，使铸件在凝固过程中通过浇口得到补缩，实现顺序凝固。
Casting Technology of Large Machine Tool
Bed Castings
Large machine tool castings are mainly used
for flat plate manufacturing of machine tools, simply accept the casting
process.
Low pressure casting (LPC) is a casting
method that enables liquid metal to complete filling cavity and solidification
process under pressure. Because the pressure used is low (20-60 kPa), it is
called low pressure casting. The process is as follows: in a sealed crucible
(or sealed tank), dry compressed air is introduced into the crucible. Under the
action of gas pressure, the liquid metal rises along the riser tube into the
straight runner 3, enters the cavity 1 smoothly through the inner runner 2, and
maintains the gas pressure on the liquid surface of the crucible until the
casting solidifies completely. Then the gas pressure on the liquid surface is
relieved so that the solidified liquid metal in the riser can flow back to the
crucible, and then the casting is opened and removed. The basic characteristics
of low pressure casting process: filling speed and pressure can be adjusted
appropriately.
There are two kinds of moulds used in low
pressure casting: metal and non-metal moulds. Metal moulds are mostly used for
large-scale production of non-ferrous metal castings, and non-metallic moulds
are mostly used for single small-scale production such as sand moulds, graphite
moulds, ceramic moulds and molten model shells, which can be used for low
pressure casting, while sand moulds are mostly used in production. However, the
permeability and strength of sand moulding material for low pressure casting
should be higher than that of gravity casting. The gas in the cavity is
discharged by exhaust duct and sand pore. In order to make full use of liquid
metal feeding castings from bottom to top under pressure in low pressure casting,
it is necessary to consider solidifying the castings away from the gate at
first, and solidifying the gate at last, so that the castings can be
compensated through the gate in the solidification process, so as to realize
sequential solidification.
Company name: botou zhuoyuan mechanical equipment manufacturing co.,LTD
Registered
address: jiaohe development zone, botou city, hebei province
Fax
number: 0317-8031093
Contact
information: 15369812793 (WeChat with the same number) liansheng chu
Postcode:
062151
Enterprise
email:
1358827475@qq.com
Account
Opening Bank: Botou Branch of Bank of China
Account
number: 100399943203
Agricultural
bank account number: 6228481739059615270
http://zhuoyuanjixie.com