论文部分内容阅读
1.2万千瓦抽气式汽轮机和1.2万千瓦冷凝式汽轮机的后气缸均为铸铁件,由于结构复杂,浇铸困难,所以很难保证产品质量,经常发现有局部大面积的气孔、夹渣及穿透性不规则裂纹,而使几吨重的工件报废。能否用焊补的办法来弥补这些缺陷?几年来我们对各种大型铸件缺陷进行了修复焊补,摸索了一些经验,取得了比较好的效果。在我们焊补修复的气缸中,最重的达5.5吨,例如其中有一台气缸,在侧面有一条长1.5米、宽30～50毫米、厚度为40毫米的穿透性裂纹。这样严重的缺陷,若要一次焊补成功,采用热焊法劳动强度大,且整体加热也麻烦;局部加热散热快也无法保温。很难保证焊接质量,
1.2 MW exhaust steam turbine and 12 MW condensing turbine rear cylinder are cast iron parts, due to the complex structure, casting difficult, it is difficult to ensure product quality, often found in a large area of local pores, slag and the penetration Irregular cracks, leaving several tons of heavy scrapped. Can make up for these defects with welding repair methods? Over the past few years we have a variety of large casting defects repaired welding repair, groping some experience, and achieved good results. The heaviest of our welded and repaired cylinders are up to 5.5 tons, for example one of them has a cylinder on the side with a penetrating crack of 1.5 mm in length, 30-50 mm in width and 40 mm in thickness. Such a serious flaw, to a welding success, the use of hot welding method, labor-intensive, and the overall heating is also troublesome; local heating fast cooling can not be insulated. It is difficult to ensure welding quality,