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农业修理部门经常碰到需要焊补铸铁零件中的裂缝。众所周知,焊接铸铁的最好方法是热焊,在那种情况下,把零件预先加热到650～700℃,并且在焊接以后保证零件缓慢的冷却。但是机器修理站和苏维埃农场的修理工场中不设有加热炉及专门用于加热零件和随后使零件缓冷的装置。为此,在农业的修理实际中大都采用各种冷焊铸铁的方法。下面叙述诺吉斯克机器修理站焊工维其塔洛夫和技术指导员马尔可夫研究成功的一种冷焊铸铁的方法:堆置退火焊道冷焊铸铁法。该法用白垩涂层低碳铜焊条,以在先堆焊好的焊道表面上堆焊的单个短焊缝(25～50毫米)进行;在这种情况下,第二条焊道用作前一条焊道金属退火的热源。焊接分散进行,同时在堆置每两层焊缝(基本焊缝和退火焊缝)以后,将零件冷却到周围大气温度。用这种短的双重焊缝并间隔地冷却焊接,一直到所有裂缝焊补好,或者将铸敛零件的个别部分焊好为止。
Agricultural repair departments often encounter the need to repair the cracks in the cast iron parts. It is well known that the best method of welding cast iron is hot welding, in which case the part is preheated to 650-700 ° C and the parts are cooled slowly after welding. However, there are no furnaces and fixtures dedicated to heating parts and then slow cooling of the parts in the repair shops of the machine repair stations and the Soviet farm. To this end, in the practice of agriculture are mostly used in a variety of cold welding cast iron method. The following describes a method of cold-welding cast irons successfully researched by Markovalov, technical instructor and welder at Nikiškís Machine Repair Station: Cryogenic welding of cast-in-place weld bead. The method is carried out with a chalk coated low carbon copper electrode in the form of a single short weld (25-50 mm) to be welded on the surface of the previously welded bead; in this case, the second bead acts as Previous weld metal annealing heat source. The welding is dispersed while the parts are cooled to ambient atmospheric temperature after each two layers of weld (base weld and annealed weld) have been stacked. Use this short, double weld and cool the weld intermittently until all cracks have been repaired or the individual parts of the cast part have been welded.