The joint pontes of the front undercarriage of an aircraft is a fatigue critical part, its fatigue life has to be estimated exactly.

某型飞机前起落架后接头连接区为疲劳危险部位，必须准确地估计疲劳寿命。

This article describes the process, equipment, operating performance and pontes for attention for adding heater and protective device for traditional low-pressure shifting furnace.

简要介绍了传统低变炉增设开工加热器和保护器工艺、设备、运行优点及注意事项。