30分求专业英语翻译....软件翻译的不要，要快啊，采纳后追加10分

Question

3.2.2Types of Sand Molds
Sand molds are characterized by the types of sand that comprise them and by the methods used to produce them. There are three basic types of sand molds: greensand, cold-box, and no-bake molds.
The most common mold material is green molding sand, which is a mixture of sand clay and water. The term“green”refers to the fact that the sand in the mold is moist or damp which the metal is being poured into it. Greensand molding is the least expensive method of making molds.
In the skin-dried method, the mold surfaces are dried, either by storing the mold in air or by drying it with torches. There molds are generally used for large casting because of their higher strength.
Sand molds are also oven dried (baked) prior to pouring the molten metal; they are stronger than greensand molds and impart better dimensional accuracy and surface finish to the casting. However, this method has drawbacks: distortion of the mold is greater; the castings are more susceptible to hot tearing because of the lower collapsibility of the mold; and the production rate is slower because of the drying time required.
In the clod-box mold process, various organic and inorganic binders are blended into the sand to band the grains chemically for greater strength. These molds are dimensionally more accurate than greensand molds but are more expensive.
In the no-bake mold process, a synthetic liquid resin is mixed with the sand; the mixture hardens at room temperature. Because bonding of the mold in this and in the cold-box process takes place without heat, they are called cold-setting processes.
The following are the major components of sand molds (Fig.3-2):
(1) The mold itself, which is supported by a flask. Two-piece molds consist of a cope on top and a drag on the bottom. The seam between them is the parting line. When more than two pieces are used, the additional parts are called cheeks.
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Answer 1

3.2.2砂模的类型
砂模依据组成砂的不同类型和生产的不同方法来分类。砂模有三种基本类型：湿型砂, 冷箱砂 和免烘烤砂模。
最常见的模型材料是湿型砂，也就是陶砂和水的混合物。名字中的湿（green）是指在金属液倒入模具中时模具中的砂是潮湿的。湿型砂铸模是制造模具花费最少的方法。
在表面干燥法中，模具表面通过存放模具于空气干燥或者用火干燥。这种模具因其强度而通常被用于大型铸造。
砂模也可在注入金属液前烘烤；这种比湿型砂模要更强韧而且有更好的尺寸准确性和表面稳定性。但是，这种方法也有缺点：模具变形度更高；由于其低损坏度而更易产生热裂纹；因为其干燥时间的要求使得生产率也相对较低。
在冷箱铸模的过程中，不同的有机和非有机粘结剂一起混合在砂中使砂粒化学结合以达到更高强度。这种模具在尺寸上比湿型砂更准确但更加昂贵。
在免烘烤铸模中，一种人造液体树脂与砂混合；混合物在室温条件下会变坚硬。因为模具的结合过程在冷箱铸模法中不需要热量的提供，所以被叫做冷固过程。
下列是砂模的主要组成物(Fig.3-2):
(1) 模具本身由铸模箱组成。两部分铸模箱分为上砂箱和下砂箱。两部分之间的接合处是分界线。当需要使用多于两部分时，添加的部分叫中砂箱。