What is a sanitary valve?
Apr 07, 2024| As the name suggests, a sanitary valve is one that meets specific health and safety standards for food, beverage, medical and other applications. The sterility of hygienic valves is critical to maintaining the purity of consumables flowing through the valve. The valve body is usually made of stainless steel that meets high hygiene standards. All parts that come into contact with fluid, gas or slurry media are mirror polished. The degree of polishing and cleaning must comply with the hygienic standards specified for its industrial function. Mainly used in food processing, pharmaceutical factories, hospitals and other health fields. It is also used in places with high health requirements and zero tolerance for physical and chemical hazards.
How many types of sanitary valves are there?
Sanitary valves can come in thousands of variations, but are divided into three different types based on their mechanical movement. The three different categories are linear motion valves, rotary motion valves, and quarter-turn valves.
Linear motion valves utilize closures and move in a straight line to allow, stop or restrict the flow of media. Some common examples of linear motion valves include gate valves, globe valves, diaphragm valves, pinch valves, and lift check valves.
Rotary motion valves use a valve closure that moves along an inclined or cylindrical path. Some of the most common types of rotary motion valves are butterfly valves, ball valves, plug valves, eccentric valves, and swing check valves.
Quarter-turn valves are basically rotary motion valves that require only about a quarter-turn (or 0 to 90°) of stem movement to go from a fully open position to a fully closed position and vice versa.
Of the three different valve types, not all are considered sanitary. Keep in mind that sanitary valves must meet special sterility requirements, particularly the valve body and sealing components. The sealing surface of the valve seat must be non-toxic. For example, the materials of hard seal and soft seal can be stainless steel and rubber respectively. If we narrow it down further, the most common types of sanitary valves are sanitary butterfly valves and sanitary ball valves. Other common sanitary valves include sanitary check valves, sanitary solenoid valves, sanitary diaphragm valves, etc.
What is a sanitary ball valve?
As the name suggests, sanitary ball valves utilize a ball with a hole drilled into it that passes through an intermediate swivel joint installed on the valve body. When the hole in the ball is oriented in the same direction as the pipe, it will operate at full flow. However, once the hole is oriented 90 degrees perpendicular to the pipe direction, the hole in the ball can rotate away from the pipe direction, causing flow to be restricted and eventually shut off completely.
Although there are many types of ball valves produced by different manufacturers, nearly all of them have the same operating functions. You can find different alternatives to ball valves by searching in the market. As a potential customer, you should take some time to familiarize yourself with all the options and compare any product benefits to the needs of your processing system. Valve manufacturers are increasingly focusing on end-user comfort and convenience. They always try to interpret the needs and tastes of their potential customers and update the quality of their products accordingly.
Are butterfly valves hygienic?
Yes. The sanitary butterfly valve is designed with a single eccentric structure, and the soft seal is different from the middle section. The butterfly valve disc is installed in the diameter direction of the pipe. In the cylindrical channel of the butterfly valve body, the disc-shaped butterfly plate rotates around the axis, and the rotation angle is from about 0° to 90°, making the valve from fully closed to fully open, and vice versa.
The valve body and valve disc of the sanitary butterfly valve are processed by high-precision CNC lathes. Sanitary butterfly valve has compact structure, light weight, simple structure and few parts. Using a butterfly valve is simple and convenient; the disc only needs to be rotated 90° to open and close quickly and provide reliable fluid control characteristics. The sanitary pneumatic butterfly valve should be kept in the fully open position. The thickness of the butterfly plate provides the medium flow rate flowing through the valve body. Therefore, the pressure drop caused by the small valve has good flow control characteristics. Sanitary butterfly valves have two types of seals - ballistic seals and metal seals. Elastomeric sealing valves can be embedded in the valve body or attached around the valve disc.
Mechanical seal requirements for sanitary valves
Sanitary valves must be manufactured to meet these mechanical seal requirements:
Comply with GMP requirements
Surface fineness must be 1.6 or above
Must be able to clean in place and disinfect in place contact surfaces
Must provide smooth flow and transition of media without material buildup
There must be a structure to prevent material from escaping beyond the sealing surface.
What is the use of sanitary valves?
Sanitary valves are used in the food and beverage industry for the connection and control of pipelines handling fluid and semi-fluid materials. Since they are made of stainless steel, the hygienic quality of materials during transportation can be guaranteed. Sanitary valves are also easy to clean and disinfect, keeping pipelines clean and hygienic.
Various industrial applications have their own specifications for the material construction of sanitary valves. Most are made of stainless steel, especially SUS304 and 316L. Both materials are produced to meet the special requirements of a variety of food and biopharmaceutical sectors.