冒口：是只为避免铸件出现缺陷而附加在铸件上方或侧面的补充部分。
Rir: is added to avoid the casting defects and attached at the top or side casting parts.
功能：在铸型中，冒口的型腔是存贮液态金属的空腔，在铸件形成时补给金属，有防止缩孔、缩松、排气和集渣的作用，而冒口的主要作用是补缩。冒口的设计功能不同的冒口，其形式、大小和开设位置均不相同。
Function: in the mold cavity, cavity of a rir is the storage of liquid metal, recharge metal in casting formed, prevent the shrinkage hole, shrinkage porosity, exhaust and collection slag, and the main function of a rir is feeding. Design of rir in different rir, its form, size and location are not the same.
1、功能
在铸型中，冒口的型腔是存贮液态金属的空腔，在铸件形成时补给金属，有防止缩孔、缩松、排气和集渣的作用,而冒口的主要作用是补缩。
Function: In the mould cavity, cavity of a rir is the storage of liquid metal, recharge metal in casting formed, prevent the shrinkage hole, shrinkage porosity, exhaust and collection slag, and the main function of a rir is feeding.
2、种类：
2.1、普通冒口:用普通造型材料做的冒口叫普通冒口；
2.2、保温冒口:用保温材料做的冒口叫保温冒口,保温冒口中的金属液比普通冒口凝固时间长，节省金属；
2.3、发热冒口:在冒口材料中加入发热剂，在浇入金属液后，发热剂反应发热，使金属液能保持更长时间在液态下，比保温冒口更节省金属。
2. Species:
2.1, The common Rir: ordinary materials do call ordinary rir rir;
2.2, Insulating Rir: made of heat insulating material called insulation rir rir, the liquid metal
宠物狗掉进粪坑
in the rir rir than ordinary long solidification time, save metal;
2.3, Exothermic Rir: join the heating agent in rir material, in pouring into the liquid metal
onaccountof
after heating agent, reaction heat, so that the liquid metal can maintain a longer
time in the liquid condition, save more metal than insulating rir.
3、设计：
功能不同的冒口，其形式、大小和开设位置均不相同，所以，冒口的设计要考虑铸造合金的性质和铸件的特点。
3. Design:
The different functions of the rir, the form, size and location are not the same, so, the characteristics of rir design must consider the properties and casting alloys..
冒口
2014广东高考语文①对于凝固过程中体积收缩不大的合金(如灰铸铁)，或不产生集中缩孔的合金（如锡青铜），冒口的作用主要是排放型腔中的气体和收集液流前沿混有夹杂物或氧化膜的金属液，以减少铸件上的缺陷。这种冒口多置于内浇口的对面, 其尺寸也不必太大。
一整天英语
Rir
For alloy solidification shrinkage small (such as gray cast iron), or do not produce concentrated alloy shrinkage (such as tin bronze), rir main function is to discharge the cavity of the gas and fluid flow front mixed with liquid metal or oxide inclusion, in order to reduce the defects of castings. The opposite the rir at the gate, its size is not too large.
②对于要求控制显微组织的铸件，冒口可以收集液流前沿已冷却的金属液,避免铸件上出现过冷组织。图2是单体铸造的活塞环，在内浇口的对面设置一个小冒口来收集冷金属，该处就不会因金属过冷而出现白口组织，导致铸件报废。这类冒口的大小和设置部位，应根据铸件的显微组织要求确定。
The requirements for the control of the microstructure of liquid metal castings, rir can flow front has been collecting liquid, avoid cold organization castings. Figure 2 is the piston ring monomer casting, opposite the gate is a small rir to collect the cold metal, it will not becau of metal cold and white tissue, resulting i
n casting scrap. The rir size and tting position, should be bad on the microstructure of casting requirements determine.
牛津字典③对于凝固期间体积收缩量大而且趋向于形成集中缩孔的合金（如铸钢、锰黄铜及铝青铜等），冒口的主要作用是补偿金属液在型腔中的液态收缩和铸件凝固过程中的收缩，以获得没有缩孔的致密铸件。铸件在铸型中冷却时，最薄的部位先凝固，其收缩可由附近较厚的部分补偿；较厚部分凝固时，又可由最厚部分得到补偿；最厚部分凝固时，如得不到外来的补偿，该处就会形成大缩孔。在这种情况下，冒口的作用就是要补偿铸件最后凝固的部分，所以要置于铸件最厚部位的上方或侧面，并且它的凝固要求晚于铸件的最厚部分。图3是一个套筒形铸钢件，最厚部位上方设有3个冒口，为表示致密的铸件和冒口中的缩孔，将铸件及其一个冒口切去了一半。图中的补正量是为改善冒口对铸件的补给而在铸件上增设的局部加厚。由于冒口冷却最慢，因补缩和自身收缩而引起的缩孔就会只产生在冒口中。这类冒口及相关工艺补正量的设计是铸造工艺设计中的重要环节，冒口的尺寸一般都用计算方法确定，重要的大型铸件可用计算机辅助设计。可通过多种技术措施来提高冒口的补缩效率,例如,中、小型铸件可在冒口周围加一个保温套或发热套，以减缓冒口的凝固达到缩小冒口尺寸的目的；大型铸件除可用保温套或发热套外，还可在冒口顶部用电弧或
商务英语翻译考试
火焰加热以减缓其凝固。提高冒口补缩效率的另一种途径是采用不同的方法增加冒口中的压力。
For during solidification shrinkage and tend to focus on the shrinkage of alloy formation (such as steel, mangane brass and aluminum bronze), the main function of a rir is compensation of molten metal in the cavity of the liquid contraction and solidification shrinkage to get in, no shrinkage of den castings. Casting cooling in the mold, the thinnest part of first solidification, part compensate the shrinkage can be near a thicker; the thicker part during solidification, which can be compensated by the thick part; the thickest part of solidification, such as the lack of external compensation, it will form a large shrinkage. In this ca, the role is to compensate the rir casting and solidification part, so the top or side face in the thickest part of the casting solidification, and it requires the thickest part of after casting. Figure 3 is a barrel shaped steel castings, 3 rir is arranged above the thick parts, for shrinkage casting and rir in the castings, rir and a cut in half. A correction amount in the
continue的意思figure is to improve the rir on the casting supply locally thickened with the casting of. The rir cooling slowest, becau of shrinkage and autogenous shrinkage caud by shrinkage can be produced only in the rir. The design of this kind of rir and related process correction amount is an important link in the design of foundry technology, rir size is generally ud for large casting method, can be ud in computer aided design important. Through a variety of technical measures to improve the efficiency of rir feeding, for example, in, small castings in rir peripheral plus a thermal sleeve or a heating sleeve, the solidification slow rir to narrow the rir size; large castings except available insulating sleeve or fever ts, but also to slow its solidification by arc or flame heating in the rir top. Another way to improve the rir supplement shrink efficiency is using different methods to increa the pressure in the rir.
