What are Pressure Regulators?
In industrial fluid systems, maintaining stable pressure control is critical to safe system operation. Pressure regulators reduce high inlet pressure and stabilize it at a lower level as demanded, and respond to outlet pressure changes to maintain or control the desired system pressure.
Basic Components
Loading Mechanism
The loading mechanism functions to apply a downward loading force from the top of the pressure regulator. FITOK pressure regulators adopt the spring-loaded mechanism, which is most widely used in pressure regulators for its reliability and low cost, and the loading force can be adjusted by compressing the spring with the operating handle.
Sensing Mechanism
The sensing mechanism allows the poppet to rise and fall after sensing the outlet pressure changes of the pressure regulator. Diaphragms and pistons are two typical sensing mechanisms. A diaphragm is usually used for low-control, pressure sensitive high purity applications such as the semiconductor industry. FITOK Hastelloy diaphragm sensing mechanism ensures excellent sensitivity and set point pressure stability. A piston cannot be used in high purity applications due to the restriction of O-ring seal, but can be used to regulate higher pressures for its higher pressure bearing capacity than a diaphragm. The piston sensing mechanism is also more resistant to peak pressure damage and has a short stroke, thus maximizing cycle life.
Controlling Mechanism
The controlling mechanism acts to reduce a higher inlet pressure to a lower outlet pressure, and the main component of the controlling mechanism is the poppet. Through the movement of the poppet toward or away from the seat, the flow area within the regulator can be adjusted to realize the purpose of reducing fluid pressure to the desired outlet pressure. In diaphragm pressure regulators, there are two types of pressure regulators— free poppet and tied diaphragm, depending on whether the poppet is connected to the diaphragm. For the free poppet construction, the poppet is only in contact with the diaphragm when the outlet pressure is equal to or lower than the set pressure.
However, for the tied diaphragm design, the diaphragm and poppet are mechanically connected, and when the outlet pressure rises above the set pressure, the diaphragm flexes upward to pull the poppet moving upward, thus achieving “Positive Shut-off” for better body seal and added safety. In addition, FITOK tied diaphragm pressure regulators are designed with no threads or springs in the wetted area to improve system cleanliness, which are applicable for ultra high purity applications.