明杆平行式双闸板闸板
double disk parallel gate valves
电动平行式双闸板闸板
electric double disk parallel gate valves
平行式闸阀
parallel slide gate valve
同杆平行双回线
parallel double transmission line on the same tower
double transmission line on one pole
平行双闸板
double disc parallel seat
暗杆楔式闸阀
non-rising stem wedge gate valve
non-rising stem wedge sluice valve
测杆式平衡
balancing with measuring rod
杆式行波型超声电机
bar-type traveling wave ultrasonic motor
Bar-type t raveling wave ultrasonic motor
井口暗杆闸阀
non-rising stem gate valve for wellhead