余热排出系统（JNA）正常运行时包括哪些借用设备？
参考答案：
1）借助JNG1的管道与一回路相连。
2）借助JMN系统的泵和热交换器实现余热排除。
Was it ______ his daughter with her work _____ the man spent the whole evening at home?
A．to help, that
B．help, when
C．helping, that
D．helped, which
焊件的整体预热是为了减少（）。
A.弯曲变形
B.焊接应力
C.扭曲变形
