A diaphragm valve is a linear motion valve that is used to start/stop and control fluid flow.
Method Of Control
The diaphragm valve uses a flexible diaphragm that is connected to the compressor by studs printed into the diaphragm. An example of the process is pinching the closed liner to provide shut-off, the diaphragm is pushed into contact with the bottom of the valve body to provide shut-off. Usually manual diaphragm valves are ideal for flow control by offering variable openings and precision to control pressure drops through valves.
The handwheel is rotated until the desired amount of media flows through the system. Section For the application of start and stop, the handwheel is rotated until the compressor pushes the diaphragm to the bottom of the valve body to stop the flow or lift the bottom until the flow can pass.
The diaphragm valve (or membrane valve) consists of a valve body with two or more ports, a diaphragm, and a "weir or saddle" or a seat where the diaphragm closes the valve.
Usually the valve body can be made of plastic, metal, wood or other materials depending on the intended use or need.
Initially, diaphragm valves were developed for use in industrial applications and / or pipes. Then with the development of current technology, designs are adapted for use in the bio-pharmaceutical industry by using suitable materials that can withstand sanitation and sterilization methods. And this is very helpful for industries that use diaphragm valves.
There are two main categories of diaphragm valves: one type of seal over "weir" (saddle) and the other (sometimes called a "full hole or straight road" valve) on a chair. Weir types or saddles are more commonly used in slurry applications but there are also process valves.
While the diaphragm valve comes in the form of a two-port (2-2 diaphragm valve), they can also come with three ports (3-way diaphragm valves also called T-valves) and many more (called block-valves). When more than one is included, they need more than one diaphragm seat; However, special dual actuators can handle more ports with one membrane.
There are two types of diaphragm valves based on their use can be manual or automatic. What is usually applied by them is generally as a closing valve in process systems in industry, food and beverage, pharmaceutical and biotech industries. Because of the previous generation this valve was not suitable to regulate and control the flow of processes, but new developments in this field have succeeded in overcoming this problem.
There are a number of other well-known ones, such as two-way diaphragm valves being turned off, other types include: Three-way deadleg valve, sterile access port, block and bleeding valve, bottom valve and tank.
The diaphragm valve gets its name from a flexible disc that comes into contact with a chair at the top of the valve body to form a seal. The diaphragm is a flexible element that is responsive to pressure that transmits power to open, close, or control valves. The diaphragm valve is associated with a pinch valve, but uses an elastomeric diaphragm, rather than an elastomeric liner on the valve body, to separate the flow of flow from the closing element.