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一、前言型砂在铸造生产中是一种普遍而大量采用的造型材料。而原砂都是从外地运载来的;单就上海地区而言,近的来自南京、宁波,远的来自江西、福建等地,甚至也有从内蒙等更远的地方运来。由此不难想象,为了铸造生产上的需要,须源源不断地运输大量的砂子,给交通运输增加不少负担。在铸造生产中,特别是铜铸件的生产,大量使用的造型材料是石英砂。石英砂因具有耐火度高的特点,多少年来一直是作为铸钢件生产中的重要材料。但是,石英砂最大的缺点是。会使铸造工人患矽肺病。据国外资料统计,在12个欧洲国家中六年内患矽肺病的铸造工人达到60万人,尤其是铸钢车间的工人占的人数最多。由此可见,矽肺病对铸造工人的身体健康有极大的危害性。同时石英砂用于生产大型钢铸件等会产生粘砂现象,使清砂工作发生困难,而且它的热膨胀会引起包砂、鼠尾等的铸件表面缺陷。近些年来,曾研制出其它型砂,虽能克服石英砂的一些缺点,但也存在不少问题,如缩沉现象、气孔问题
First, the foreword Sand in the casting production is a widespread and extensive use of modeling materials. The original sand was carried from the field. In the case of Shanghai alone, nearly 40 people came from Nanjing and Ningbo, and far from Jiangxi and Fujian, even from farther places such as Inner Mongolia. It is not hard to imagine that, in order to cast the need for production, a large amount of sand must be continuously transported to increase the burden on transportation. In casting production, especially in the production of copper castings, a large amount of molding material used is quartz sand. Quartz sand because of the characteristics of high refractoriness, for many years has been as an important material in the production of castings. However, the biggest drawback of quartz sand is. Casting workers will suffer from silicosis. According to statistics from abroad, the number of foundry workers suffering from silicosis in six European countries in 12 European countries reached 600,000, especially in the steel casting plant. This shows that silicosis is extremely harmful to the health of foundry workers. At the same time quartz sand for the production of large-scale steel castings will produce sticky sand phenomenon, make sand work difficult, and its thermal expansion will cause sand, tail and other casting surface defects. In recent years, other sand has been developed, though it can overcome some of the shortcomings of quartz sand, but there are also many problems, such as shrinkage phenomenon, porosity problems