ขั้นตอนการใช้เว็บไซต์ คู่มือการใช้เว็บไซต์ The seat is the orifice that presses versus the disc when closing the valve. The seat and disc usually are made from exactly the same material. As soon as the seat or disc is broken, the valve will turn into passing and not able to prevent the stream. https://diaphragmseal67898.xzblogs.com/56441519/the-best-side-of-pneumatic-actuator-butterfly-valve