Resilient seated gate valves are a popular choice for isolating, regulating, and throttling the flow of liquids in industrial piping systems. The design incorporates an elastomeric seal that provides a tight shutoff without the need for metal-to-metal contact like traditional wedge gate valves. This enables resilient seated gate valves to offer significant advantages over standard gate valves.
Advantages Of Resilient Seated Gate Valves
A key benefit of resilient seated gate valve is ease of maintenance. The elastomer seal on a resilient seated gate valve is replaceable without removing the valve from the piping system. Replacing a worn seat only requires loosening a few bolts to remove the seat from the valve body. This allows for seat replacement without shutting down or draining the system, saving substantial time and maintenance costs.
Elastomer seats also provide a “soft” sealing surface that is less prone to damage from pipe strain, line debris, and water hammer events. This helps resilient seated gate valves maintain a drip-tight shutoff for years without needing to be rebuilt or replaced. However, should the valve body sustain damage, individual parts like the stem, bonnet, and seats can often be replaced instead of replacing the entire valve.
The resilient seal also allows resilient seated gate valves to provide a smoother shutoff compared to traditional metal-seated valves. Closing a resilient seated gate valve does not involve metal-to-metal contact that can cause vibration and noise as the sealing surfaces come together. Instead, the soft elastomer conformingly seals against the valve seat for a more gradual, smooth shutoff that minimizes system shock.
Various Materials Of Seated Gate Valves
Resilient seated gate valves are available with a range of sealing materials to accommodate various fluid properties and process conditions. Common seats options include:
• Nitrile rubber – For water and aqueous fluids up to 212 degrees Fahrenheit
• Buna-N – For water, aqueous fluids, and light oil up to around 250 F
• Viton – Recommended for oils, solvents, and chemicals up to around 400 F.
• PTFE – Suited for most aggressive chemicals up to around 450 F.
The seats are also as designed to withstand normal pressure-temperature ratings of industrial piping systems from 150-2500 psi and -20 to 450 F. Resilient seated gate valves with PTFE seats can operate up to temperatures as high as 600 F.
Resilient Seated Valves VS. Metal Seated Gate Type
Compared to metal seated gate valves, resilient seated valves generally offer lower cost of initial purchase. And also long term cost of ownership due to reduced downtime for maintenance. Metal seated valves often require stem seals and packing to prevent external leakage, while resilient seated valves typically utilize more reliable static seals. Resilient seated valves are also more suitable for applications. Meanwhile, it involves frequent valve operation since the soft sealing surface experiences less wear.