明杆平行式双闸板闸板 Double Disk Parallel Gate Valves

明杆平行式双闸滑阀 rising-stem double-disk parallel slide valve

双闸板式防喷器 preventer of double ram type

明杆平行式双闸板闸阀 double disk parallel gate valves

电动平行式双闸板闸板 ElectricDoubleDiskParallelGateValves ; Electric Double Disk Parallel Gate Valves

电动平行式双闸板闸阀 Electric Double Disk Parallel Gate Valves