Why Should You Use Sanitary Angle Seat Valves

When getting sanitary angle seat valves for the various sterile processing applications, essential specifications to be considered include the diameter of the valve seat, body material, end connection, working temperature, and pressure.

The valve body can be 316 stainless steel, plastic or forged from brass. Pick a valve forged from steel for the long-life cycle. Typical wetting materials include CF3M or 316 ss. In terms of end connections, you can get the threaded (thread size 1/2″ -3″), clamped, flanged (tailor-made) or welded valves. For your sanitary applications, go with the tri-clamp process connection valve.

The valve can be configured for bi-directional flow or installed such that flow direction is from above or below the seat. Flow from below the seat reduces the effects of water hammer.

Angle seat valves deliver several (millions) cycles in tough applications involving aggressive media, gas, steam, and liquids. They’re designed to withstand temperature as low as -26A and as high as 400A with up to 500 psi of pressure.

In terms of flow rate, you have to determine the Kv-value your application requires plus the medium characteristics. Kv-value is the rate at which water flows when the pressure drops by 1 bar. Make use of valve sizing calculator to get the necessary flow rate and then choose the best valve size.

For the seat materials, you can get valves with FDA approved PTFE seats. The type of sealing determines the working temperature too.

Sanitary angle valves feature robust designs for an extended life cycle and smooth operations. The angle seat valve is piston operated and can feature a closure spring. The valve seat gets positioned at an angle for a restriction-less flow upon being unplugqed. A high-pressure pilot medium (compressed air, water, oil) in a cylinder is used to exert pressure on the valve actuator.

Sanitary angle seat valves feature large pistons for more output pressure. The pistons usually multiply the input force. And the large-sized pistons are suitable where the air supply is very low to generate necessary force with less input force.

Sanitary angle valves also feature improved sealing to keep off emissions and prolong the media life. The plug seats on Teflon PTFE seats and is connected to the piston on the other end. The design is such that the piston retracts further away from the valve seat to allow for maximum flow rate.

For mounting, the piston is designed with ports (either threaded or NAMUR style) for easier plugging without the use of lubricants or screws that would otherwise damage the equipment.

In terms of rotation, the piston head is designed for 360A to give the air and solenoid lines maximum position.

The compressed pilot medium is kept in the upper section of the cylinder so that enough pressure gets built up forcing the piston or diaphragm to provide the necessary motion for dislodging a plug from the fluid path. The mechanical motion created by the actuator can be linear or rotary, in angle seat valves it’s the latter.

To prevent hydraulic shock (water-hammer) upon the sudden closure of the valve modern designs feature protection mechanisms to keep the valve from propagating pressure throughout the fluid upon closing.

Water-hammer protection keeps the pipes from collapsing and prevents annoying vibrations and noise when the valve closes.

Closing can be done normally using a spring or through double-acting. In normal closing the spring compression is released, the seat returns to its position effectively sealing off the fluid path. In double-acting, the return spring is missing, so the pilot medium provides the necessary mechanism.

The pressure ranges the valve operates in depends on the pressure of the pilot medium used, the pressure of the controlled fluid, the direction of flow of the controlled fluid and construction parameters. The construction parameters could be the spring force, the diameter of the fluid path (orifice) and that of the actuator cylinder.