Plunger valves working principle
Plunger valve is composed of valve body, valve cover, valve stem, plunger, hole rack, sealing ring, handwheel and other parts. When the handwheel rotates, the valve opens and closes by driving the plunger up and down in the middle of the hole rack by the valve stem. The interference fit between the plunger and the sealing ring is adopted in the valve. By adjusting the flange bolt in the pressure cap, the lateral force produced by the compression of the sealing ring is sealed with the orifice in the valve body and the outer circle of the plunger, thus ensuring the sealing of the valve, eliminating the leakage inside and outside, and at the same time, the opening moment of the valve is small, so that the valve can be opened and closed quickly. Compared with globe valve, plunger valve has long service life and labor saving operation. But the regulating stroke is longer than the globe valve, so throttling control is more difficult than the globe valve. Neither is suitable for places with clear requirements for regulation. Working Principle of Plunger Valve Globe valves VS plunger valves Characteristic of plunger valve Types of plunger valves Technical parameters of plunger valve Size of Plunger valve Use of Plunger Valve
Plunger control valve has unique benefits that make the valve specifically suitable for the more special and severe service control applications. Axial flow designs are streamlined annular flow path and evenly distributed flow through the cage – this reduces high local velocities, turbulence and impacts of flow jets and particles. This is fundamental for reliable valve performance because vibration, erosion and unbalanced flow and forces are avoided.
Decreasing Cavitation –
Shut-Off Valves, such as Gate Valves, and Butterfly Valves can restrict the flow of liquids and can cause very high flow velocity in the throttled position. The design of these valves impinging the flow to the pipe walls and the valve interior surfaces. Plunger Valves, by contrast, direct the flow of liquids passing through the plunger valve to the center of the flow element so that the implosions take place in the center of the flow stream away from adjacent pipe and valve surfaces, By redirecting and “controlling” the location of the collapsing bubbles, cavitation damage is significantly reduced.
Centering Bursts –
The Plunger Valve passes the liquid through a characterized element that prevents the cavitation from impinging on the valve and pipeline . surfaces. Liquids travel into the center of the valve or pipeline, and the cavitation “event” is directed away from the adjacent walls. Different valve trim packages allow for customized flow control based on the application. Trim packages include vanned, slotted and perforated trim. A J&S Valve consultant can assist with the proper trim package for your application. All anti-cavitation control valves are not made equally and the control of cavitation by directing the flow to the center of the valve is the proven method for controlling cavitation damage.
Plunger Valve Application :
Water application , Reservoir Inlet , Dam Outlet Control , Submersed Discharge , Semi-Submerged Discharge ,Free Discharge , Turbine Inlet , Turbine By-pass , Combined Inlet , Regulating and Safety Valve.
- Optimal control range and extremely soft closing
thanks to the crankshaft movement of the piston
furthermore supported by the Düker slidercrank gearbox
- Safe main sealing
with sturdy profile sealing ring on the piston and O-ring in the body
positioned intelligently to prevent unnecessary wear and tear
- Hygienically safe
due to deliberate water flow in the piston chamber as well as safe shaft sealing
- Long operative life
with sturdy, carefully placed guide rails
directed wear instead on the piston which can be rotated or exchanged easily
- No cavitation damage on valve or pipeline
Cavitation is directed hazard-free into the middle of the pipeline.
Depending on the operating conditions, slotted or perforated cylinder as an option
Plunger Valve advantage:Plunger Valve such as gate valves are designed to provide unobstructed flow in the fully opened position or to totally obstruct flow when fully closed. These inherently asymmetrical cross sections are unable to provide a linear control over their operating range. In contrast, the plunger Valve has characterized trim that facilitates linear control over the entire operating range. The customized trims allow for characterized flow control for each unique application.
Plunger valve Parts :