Catagories of ball valve seats

Catagories of ball valve seats

In the ball valve industry, the most important components to seal the flow control system is the valve seat or seal face. The ball cooperates with the valve seat to achieve the seal. To meet different medium applications, we TEKO have developed several ball seat designs:

1. Soft seat: usually made of PTFE, RPTFE.

Advantage: since the seal is soft, it is easy to seal the fluid.

Disadvantage: if the fluid contains particles, the fluid may scratch the seat and cause damage.

In order to make a better and wider applications, we adds some element to modify the property of the PTFE seat to improve the hardness of the seat valve. The most used are two kinds: one is 25% carbon filled TPFE, black color; the other is SS filled TFE, grey color.

The advantage of the modify TFE material is that they can be used in higher temperature and is harder than the PTFE.

2. Fire safe seat

For the soft seat design, when fire occurs, the seal will be damaged and cause leakage. It is a big risk in some industries. So we developed the fire safe design.

The fire safe design is as follow: there is a metal seal as a back-up secondary seal behind the soft seat. After the fire, the soft seat are destroyed and the pressure push the ball against the fire safe lip to a form metal-to-metal seat between the ball and the end cap fire safe lip.

3. Metal seat

There are two kinds of metal seat:

one is designed for large size soft seated, since the ball of large size valve is heavy, we need a metal seat to hold the soft ring to seal the fluid control system.

The other type is the truly metal to metal seat. The working principle is that the ball surface must be harder than the valve seat. Otherwise, the ball seal face will be scratched by the valve seat and cause leakage. And this kind of ball valve is very difficult to produce since any deviation on the ball or seat will cause leakage.

4.Lining Ball valve

For the most aggressive liquid, tthe lining ball valve will be used. In this design, all the wet parts of ball valves, indluding the ball and body, are totally lined with PTFE, PFA or other corrosion-resistant plastic.

FOR MORE INFO, PLEASE CONTACT: SALES@TEKO-VALVE.COM