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Principle structure of plunger valve The plunger valve is composed of valve body, valve cover, valve stem, plunger, handwheel, sealing ring, hole frame and other parts. When the handwheel is rotated, the plunger is driven through the valve stem to reciprocate up and down between the two sealing rings to complete the opening and closing of the valve. In the plunger valve, an interference fit is used between the plunger and the sealing ring. When the plunger is inserted into the inner hole of the sealing ring, the sealing ring is compressed and tightly hugs the plunger. At this time, the radial component force generated by the interference sealing ring will be greater than the fluid pressure, thereby ensuring sealing. When the plunger is withdrawn, the sealing ring returns to its original shape under the elasticity of the material. At this time, the fluid flows to the outlet through the hole frame and the lower sealing ring. Because the sealing ring is made of new non-metallic materials, it has good comprehensive performance and can withstand long-term high temperature and high pressure without losing elasticity. Moreover, the contact area between the plunger and the sealing ring is large. Therefore, the sealing is reliable and durable. Structural features of plunger valve 1. Threaded connection or socket welding connection straight-through plunger valve 1. Flow channel: Straight-through type 2. The valve body and valve cover are made of cast steel or steel castings, and the plunger, valve stem and isolation ring are made of stainless steel. The sealing ring is flexible graphite or polytetrafluoroethylene 3. The sealing ring and isolation ring are pressed by the valve body and valve cover connecting bolts, nuts and spring washers 4. The sealing is achieved by the outer diameter of the plunger and the inner diameter of the sealing ring 5. The opening and closing speed of this valve is slow 2. Butt welding connection straight-through plunger valve 1. Flow channel: Straight-through type 2. The valve body and valve cover are made of cast steel. 3. Other structural features are the same as No. 3. Flange connection straight-through plunger valve 1. Flow channel: Straight-through type 2. The valve body and valve cover are made of cast steel or steel castings, and the plunger, valve stem and isolation ring are made of stainless steel. The sealing ring is flexible graphite or polytetrafluoroethylene 3. The sealing ring and isolation ring are pressed by the valve body and valve cover connecting bolts, nuts and spring washers 4. The seal is achieved by the outer diameter of the plunger and the inner diameter of the sealing ring 5. The opening and closing speed of the valve is slow 4. Flange connection pressure balanced straight-through plunger valve 1. Flow channel: Straight-through type 2. The valve body and valve cover are made of steel castings: The valve stem, plunger and isolation ring are made of stainless steel ； The sealing ring and filler are flexible graphite or polytetrafluoroethylene ； The valve stem nut is made of copper alloy. 3. The sealing ring and isolation ring are pressed tightly by the connecting bolts, nuts and spring washers of the valve body and valve cover. 4. The sealing is achieved by the outer diameter of the plunger and the inner diameter of the sealing ring. 5. The plunger is hollow, with through holes in the upper and lower chambers. The valve stem is connected with the upper sealing sleeve and nut to balance the pressure in the upper and lower chambers of the plunger and save effort when opening and closing. However, the valve stem must have an upper seal and a packing seal. 6. The opening and closing speed of this valve is slow. 5. Globe-shaped plunger valve 1. Flow channel: Straight-through 2 valve body, valve cover and plunger body are made of cast steel ； The valve stem and plunger pressure ring are made of stainless steel ； The sealing ring and packing are flexible graphite or polytetrafluoroethylene. 3. The fitting place between the valve body and the plunger sealing ring is inlaid with a stainless steel bushing. 4. The sealing ring is pressed on the plunger body with a plunger pressure ring. 5. The sealing is achieved by matching the outer diameter of the plunger sealing ring and the inner diameter of the valve body bushing. 6. The valve body and valve cover are connected with bolts to ensure sealing. Use gasket 7. Use packing and upper seal to seal the valve stem. Press the packing to achieve sealing. 8. Use stem nut for valve stem transmission. Turn the handwheel to open and close the valve. 9. The plunger valve with this structure opens and closes faster than the conventional plunger valve. 6. Flange connection double valve seat pressure balanced straight-through plunger valve 1. Flow channel: Double port straight-through type 2. The valve body, upper valve cover and lower valve cover are all made of steel castings ； The valve stem, plunger and isolation ring are made of stainless steel ； The sealing ring and the packing are flexible graphite or polytetrafluoroethylene. 3. The sealing ring and isolation ring. The plunger guide sleeve uses the upper and lower valve covers. The bolts, nuts and spring washers are pressed into the valve body. 4. The plunger can move up and down in the upper and lower sealing rings and guide sleeves. The guide sleeve is equipped with a pressure balance hole, and the medium pressure can enter the lower cavity of the guide sleeve through the small hole. Sealing can be achieved by relying on the double sealing surface of the plunger and the double sealing ring in the valve body. 5. This valve is a double seat sealing plunger valve, which can pass a larger flow. Because the plunger is shorter, the opening and closing speed is larger than that of a conventional plunger valve. 6. The valve stem seal uses upper sealing and packing, and the packing gland can be pressed to achieve stem sealing. 7. The stem nut is set on the upper valve cover and the hand wheel can be turned to drive the plunger valve to open and close. Seven internal threads are connected to the right-angle plunger valve 1. Flow channel: Right angle type 2. For other structural features, please see serial number 1. 8. Flange connection right angle type plunger valve 1. Flow channel: Right-angle type 2. For other structural features, see No. 3. 9. Flange connection pressure balanced right-angle plunger valve 1. Flow channel: Right angle type 2. Other structural features