The 10Q Series unbalancedshut-off valve adopts top guided pressure unbalanced plug. It is suitable forapplications with low differential pressure. The plug and seat surfaces aresubjected to hard alloy overlay welding to ensure long-time stable running ofthe valve. For shut-off applications of media of high temperature and service conditionswith high differential pressure, we have specially designed the double-plugpressure relief type shut-off valve. The trim of this kind of valve adoptsdouble-plug structure with flow to off design. When opening the valve, firstopen the small plug, and the starting force is relatively low because the areaof thrust surface of the small plug is small. After the small plug is opened,the pressure after the valve is released and the differential pressure actingon the large plug is greatly reduced. The large plug can be opened with arelatively low actuator force. The trim of this kind of structure can meet theneed for shut-off applications in service conditions with high differentialpressure.