Pinch valves are used in maintaining and control of several fluid systems in industries today. Apparently, these valves are intended to control or seal the flow of fluids, slurries, or powders in such areas as water treatment, mining, and food industries. Among them, the most usual types contain manual pinch valve and the control pinch valve. This article focuses on describing how pinch valves work, its types including the hose pinch valve and the pneumatic as well as electric actuated pinch valve.
What is a Pinch Valve?
Basically, a pinch valve acts through squeezing or clamping a portion of the flexible tubing, the hose or sleeve, to shut off or regulate flow in the system. The feature that there are no mechanical parts which come into direct contact with the media passing through the valve is the reason why this solution is used in industries dealing with abrasive, corrosive or viscous materials.
With reference to the modes of operations, pinch valves of different types include the manual type and the control type commonly referred to as the control pinch valve systems.
Types of Pinch Valves
1. Hose Pinch Valve
Hose pinch valve is mainly designed uniquely to accommodate flexible hoses or sleeves that run through the body of the valve. The first is accomplished by using a pinching bar to pinch down on the hose and throttling the flow of media if needed. Hose pinch valves are often applied in the processes which involve slurries, powders, and solids since its functioning is not based on the complex mechanisms that may wear out due to mentioned kinds of loads.
2. Manual Pinch Valve
A manual pinch valve is one of the pinch valve variants that is operated manually; via a hand wheel pinch valve or a hand lever pinch valve. These valves are especially suitable for operating situations in which continuous flow does not require automation, and therefore, represents an inexpensive solution for use.
The operator rotates the hand wheel or pulls the lever to tight the loose or to loosen up the pinch mechanism adjusting the media flow through the flexible sleeve. Manual pinch valves are typically employed by businesses that transport abrasive or corrosive substances since its sleeve is the only part in contact with the flow and carry little wear and tear to other components.
3. Control Pinch Valve
A control pinch valve provides on/off flow control with automated or semi-automated control of the valve. It is meant for applications where slight variation in pressure or flow of the fluids or gaseous medium has to be controlled. The most common type of pinch valve is the control pinch valve and is used more commonly in the chemical and pharmaceutical industries because of the valve’s capabilities to manage sterile and corrosive media which does not get contaminated.
4. Pneumatic actuated Pinch Valve
The type of pneumatically operated valve which will be expounded in this article is the pneumatic actuated pinch valve which uses air compression in pinching operation of the valve. This kind of valve is widely used in automated processes because it needs frequent and prompt operation. Pneumatic actuation for operation remotely and it can be interfaced with large process control systems. They can be single acting pinch valve or double acting pinch valve depending to how the compressed air control the valve. In a single acting pinch valve, the opening or closure of a valve depends on the air pressure and in double acting pinch valve, both the air pressure is being used for opening the valve as well as closing the valve thus enhancing the fluid control.
5. Electric actuated Pinch Valve
In the situation where the valve is used mechanically, an electric actuated pinch valve will use an electric motor to open or close the valve. These valves offer the necessary characteristics of accuracy in delivering fluid flows as is needed in applications that must involve high level of flow control. Electric actuated pinch valves are found in processes such as pharmaceuticals, food industries, and water treatment where electric signals can regulate the degrees of openness and closure, often with low human interference.
Another advantage of using electric actuators is that they do not draw power from a compressed air supply which is a requirement that most facilities may not have……Read More
