弹簧式安全阀启闭不灵活的原因？
参考答案：
1、调节圈位置调整不当
2、内部运动零件卡阻
3、排放管阻力大，排放背压较大，安全阀开高不足
—It’s many years since I saw you last; I you at all．
—I wouldn’t have, either; if someone you by the name．
A．didn’t recognize; hadn’t called
B．didn’t recognize; didn’t call
C．haven’t recognized; didn’t call
D．recognized; hag called
夹紧工具是扩大或撑紧装配件用的一种工具。
