Metal casting processes divide into two categories based
on mold type: (l) expendable mold and (2) permanent
mold. In expendable mold casting operations. the mold is
sacrificed in order to remove the cast part. Since a new
mold is required for each new casting, production rates in
expendable-mold processes arc often limited by the time
required to make the mold rather than the time to make the
casting itself. However, for certain part geometries, sand
molds can be produced and castings made at rates of 400
parts per hour and higher. In permanent-mold casting
processes the mold is fabricated out of metal (or other
durable material) and can be used many times to make
many castings. Accordingly, these processes possess a nat-
ural advantage in terms of higher production rates.
金屬鑄造生產(chǎn)工藝分為兩大類的基礎(chǔ)模具型: (l) 消耗型模具和(2) 永久型模具。在消耗型鑄造業(yè)務(wù)中，模具必須切除多余的部分。因?yàn)橐粋€(gè)全新的模具需要每一個(gè)全新的鑄件，在消耗型模具生產(chǎn)率過程中要求做模具常常受制于時(shí)間，而不是做鑄件本身的時(shí)間。然而,對(duì)于某些部分幾何學(xué),沙型模具和鑄件可產(chǎn)生了以400部每小時(shí)的速度或更高。在永久型模具鑄造工藝的模具制作金屬(或其他耐用的材料),很多時(shí)候能用與做一些鑄件。因此,這些工藝過程就更高的生產(chǎn)率而言具有天然的優(yōu)勢(shì)。