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在地球的寒冷地区,要求机器、仪器及建筑物等应具有良好的可靠性。因为,在这些地区,人们同样需要运输,从事科学活动和开挖、建筑作业,以及原材料和产品的制备与运输。北极和南极冬天的环境气温一般为-60℃,而其中某些地区夏天的气温却高达40℃。这样,对在北极和南极作业的机器和仪器就提出了一个难题。低温情况下,金属和聚合物会变脆;润滑油变稠甚至不流动。结冰带来了不希望的载荷和摩擦阻力。温度变化的结果,很容易在电器部件上形成潮气以及产生热膨胀效应。当今,许多设备和仪器里都包含有金属和塑料部件。当温度由冬天的-50℃升至夏天的20℃时,1m长的铁棒将膨胀0.85mm。但是,一条相同长度的聚合物(如PTFE)棒,在同样温度变化下却膨胀7mm之多。极端的环境条件以及北极、南极地区的设备和仪器,必须具
In the cold area of the earth, it is required that machinery, instruments and buildings should have good reliability. Because in these areas, people also need to be transported, engaged in scientific activities and excavation, construction operations, as well as the preparation and transport of raw materials and products. Temperatures in the Arctic and Antarctic winter are generally -60 ° C, while summer temperatures in some of these areas are as high as 40 ° C. In this way, a challenge is posed to machines and instruments that operate in the Arctic and the Antarctic. Metal and polymers can become brittle at low temperatures; the oil thickens or does not flow. Icing brings unwanted loads and frictional drag. As a result of temperature changes, it is easy to form moisture on the electrical components and produce thermal expansion effects. Today, many devices and instruments contain metal and plastic parts. When the temperature rises from -50 ° C in winter to 20 ° C in summer, the 1m long iron rod will expand by 0.85mm. However, a rod of the same length, such as PTFE, expands by as much as 7mm at the same temperature. Extreme environmental conditions as well as Arctic and Antarctic equipment and instruments must be available