Description
Technical Specifications
SPECS Pilot Operated Control Valves provide unmatched tight shut-off performance for high temperature applications(Working temperature ＞230℃). In high temperature and high pressure conditions, even if the seat has a small leaking can also cause seriously erosion of the plug and seat. Therefore the Control Valves has good sealing performance is very important in these cases.The general method to improve the sealing performace is to increase the actuator size,However the Pilot Operated Control Valves improving the sealing performace by the pressure difference between lnlet and outlet of the valve, this structure can reduce the size of the actuator and improve the sealing performace.
Applicable Standard
Design & Manufacture Standard: IEC 60534-2006
Face to Face: ISA-75.03-1992
End Connection: ASME B16.5, EN1092-1, GOST33259, ASME B16.25
Test Standard: IEC60534-4
Products Range
Size: 1 1/2"~24"
Pressure Rating: ASME CLASS 150~2500
Material: Carbon steel, Stainless steel, Alloy steel, Duplex stainless steel
End: Flanged (RF, RTJ), Butt Weld, Socket Weld.
Temperature Range: -196℃~550℃
Seat Leakage: ANSI Ⅴ(No visible leakage)
Bonnet Type: Fin-Extension
Design Features
1. Fluid flow is from up to down, pilot balanced Cage Guided Control Valve has a separate pressure balanced pilot plug compared to the regular cage control valve.
2. The main plug is closed tightly by the output force of actuator and the unbalanced force from fluid pressure difference while the valve is closed. The pilot plug is closed tightly by the output force from actuator and the spring reaction force.
3. The flow capacity in the channel of pilot plug and seat should be bigger than the flow capacity in the guided ring and the gap between plug and cage, otherwise, the pressure balance cannot be established and this would lead to valve closure.
4. The opening of pilot plug is controlled within the range of 10% of the valve opening, otherwise the range of small flow valve can not be adjusted.
5. Small size, compact structure, good sealing performance
6. High ability of cut off, long service life. This series can be used for evacuation and shut-off, especially in occasions with high temperature, high pressure and large valve size.
Benefits
1. Cavitation can happen even the valve seat has a small leakage in the high temperature and high pressure difference occasions, and this would lead to valve trim damage with long-term erosion to the plug and seat. So it is vital keep complete sealing without any leakage for the valve in these occasions. Normally, increasing the output force would promote the sealing level. For pilot balanced cage guided Single Seated Control Valve, the actuator size can be reduced and sealing performance can be promoted by using the unbalanced force from the flow pressure difference. And this makes the product even more competitive.
GA Of Pilot Operated Control Valve
