论文部分内容阅读
1 前言 东风4Ｄ型机车是我国铁路为提速而开发的新型大功率内燃机车 ,自 1997年开始配属各提速机务段。该机车投入运用一段时间后 ,柴油机部分气缸盖底板在2 73ｍｍ止口处开始产生裂纹 ,并随着运用公里增加 ,部分气缸盖裂纹扩展到与气缸盖冷却水腔贯通。当柴油机工作时 ,
1 Introduction Dongfeng 4D locomotive is a new type of high-power diesel locomotive developed by our country for speeding. Since 1997, it has been attached to various speed-raising locomotive depots. After the locomotive is put into operation for a period of time, some diesel engine cylinder head bottom cracks begin to crack at the 2 73mm stop, and with the increase of km, some of the cylinder head cracks extend to pass through with the cylinder head cooling water cavity. When the diesel engine is working,