东风4C超薄管板换热器的失效分析与改进

对东风C4超薄管板换热器失效形式进行了分析，冷却管组自重变形、空气压力、冷管组自重引起的剪力和挤压应力、银磷铜钎焊的连接强度和振动是主要原因。在设计除了考虑拉脱强度、剪力、挤压力、焊接应力外，还应考虑振动的因素，管板与冷却管的连接改为锡钎焊，管组增加支撑，严格控制焊接工艺，δ取计算中的较大值。

Failure analysis and improvement of ultrathin tubular sheet heat exchanger of Dongfeng 4C

The analysis on the failure form of ultrathin tubular sheet heat exchanger of Dongfeng 4C shows that pipe group self-gravity distortion, air pressure, shear and extrusion stress by pipe guroup self-gravity, and the connection strength and vibration of brae welding of silver phosphorus bronze. During design, it should consider not only the intensile stress intensity, sheer, extrusion and welding stress but alto the factor of vibration; the connection between tubular sheet and cooling pipe should be sin braze welding; and the support of pipe group should be increased, welding technique should be controled strictly, and the value of should be selected the larger one during calculation.