在一些大功率的工程机械中，经常要用到铜轴承。这时需将两半铜轴瓦对合焊成一个整体，然后才能进行机械加工。在机械加工过程中，经常会由于钢轴承结合面焊接不牢而裂开，从而影响到零件的加工质量，有时甚至报废。过去我们在焊接铜轴瓦时，通常采用氧乙炔焰预热、然后用电烙? In some high-power construction machinery, often need to use copper bearings. At this time, the two halves of the brass bearing should be welded together into a whole body before being machined. In the machining process, often due to the welding of steel bearing interface is not strong and cracked, thus affecting the quality of the parts processing, and sometimes scrapped. In the past when we welded copper bushings, oxyacetylene flame was usually used for preheating and then ironed?