江南大学排名2017:求英文高手翻译文献,急!急!急

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III. Coolant and Cooling System
The cooling system of a diesel engine must be capable of continuously removing about 30 percent of the heat released by combustion of its fuel without overheating. Assuming a reasonably clean cooling system, this is usually not a problem. The following items should be checked:

Coolant Level
Coolant level is critical to proper operation of a cooling system. If coolant level falls to the point where air is drawn into the cooling jackets, cooling capacity will be reduced, and serious damage, including cavitations corrosion,
will result. Always check coolant level.

Coolant Composition

Engine coolant is generally a mixture of ethylene or propylene glycol base antifreeze and water. The freezing point of the mixture will depend on the relative amount of glycol used. It is important to use the best available water blended with not more than 60 percent ethylene glycol base antifreeze or 50 percent propylene glycol base antifreeze. Excessive antifreeze concentration can cause corrosion damage in the water passages.

It is equally important never to use water alone as an engine coolant. (Water is corrosive at engine operating temperatures.)

Water quality is important. The following table shows the recommended minimum acceptable characteristics for cooling system water, according to one manufacturer (Caterpillar Inc., www. caterpillar.com):

Minimum Water Quality for Coolant Use:
Properties Limits ASTM Test Methods

Recommended Additives and Inhibitors
Engine manufacturers will usually provide detailed guidance as to additives necessary to prevent corrosion or to provide supplemental lubrication of cooling system components. It is very important that the recommended concentrations of these not be exceeded. High concentrations can cause precipitation of solids, and can cause damage to seals and other internal parts. On the other hand, low concentration of coolant additives can cause cavitation pitting on the water side of the cylinder liners.
Sometimes, engine manufacturers will supply special filters which dispense additives into the coolant (controlled release filters). If an engine is fitted with these filters, then it is very important that additional additives NOT be separately added to the coolant. Conversely, if chemistry is controlled by specific additives then controlled release filters must NOT be used. USE CONTROLLED RELEASE CHEMISTRY, OR USE COOLANT ADDITIVES, BUT DO NOT USE BOTH!

三. 冷却剂和冷却系统 柴油引擎冷却系统必须能够不断排除约30%的燃料燃烧释放热量,过热. 承担相当清洁冷却系统,这通常不是个问题. 应检查下列项目: 制冷水平 冷却到正常水平是至关重要的冷却系统. 如果没有达到一级制冷空气吸入冷却外套,冷却能力会降低,而且严重损害,包括cavitations腐蚀 结果. 总检查制冷水平. 冷却组成 发动机冷却液是一种混合乙烯、丙烯乙二醇和水制药基地. 在冰点的混合物将取决于使用乙二醇相对数额. 最重要的是要利用现有的水混合不超过60%或50%乙烯丙烯乙二醇防冻剂乙二醇基制药基地. 抗凝剂浓度过高会造成腐蚀损坏的水通道. 同样重要的是,不要单发动机冷却用水. (水侵蚀的引擎运作的温度). 水质是很重要的. 下表显示推荐最低水冷却系统的特点,根据厂商之一(毛毛虫Incwww. caterpillar.com): 为冷却水使用素质最低: 试验方法ASTM财产范围 推荐添加剂和抑制剂 发动机制造商通常会提供详细的指导,以防止腐蚀添加剂或提供补充润滑油冷却系统元件. 这是非常重要的,这些建议浓度不超过. 高浓度可造成的固体沉淀,并可能导致内部零件损坏等印章. 另一方面,低浓度的添加剂,会造成冷却水在空方的对立派气. 有时,发动机制造商将提供特殊的过滤器,免冷却添加剂(过滤器控制释放). 如果这些发动机装过滤器的话,这是非常重要的,不能单独增加添加剂加入冷却. 反之,如果是由特定化学添加剂,不得使用过滤器控制释放. 释放控制使用化学添加剂或使用制冷剂,但不要使用这两个!