- Product name : Fisher Volume Booster 2625-12
- Condition: Brand new
- Brand : Emerson (Fisher)
- Origin: US
Product Description:
Fisher Volume Booster 2625-12 is used in conjunction with the positioner on the throttle control valve to increase the stroke speed. 2625NS is a nuclear service version, using elastic components, can better withstand high temperature and radiation environment.
- Delivers the volume needed for rapid actuator stroking when large input changes suddenly occur.
- Integral bypass restriction tunes the booster response so that smooth actuator motion follows the slow signal changes.
- Soft seats provide tight shutoff to reduce unnecessary air consumption and eliminate saturation of positioner relays.
- Permits high actuator stroking speeds upon demand without degrading the positioner steady-state accuracy.
- Certified for use in Safety Instrumented System (SIS) applications.
Specification of Fisher Volume Booster 2625-12:
Port Diameters
Supply Port: 9.5 mm (0.375 inch) or 12.7 mm (0.5 inch)
Exhaust Port: 2.4 mm (0.094 inch)(2), 9.5 mm(0.375 inch) or 12.7 mm (0.5 inch)
Input Signal
Positioner output
Maximum Input Signal Pressure 10.3 bar (150 psig)
Input to Output Pressure Ratio Fixed at 1 to 1
Supply Pressure Ranges
When Normally Used With Diaphragm Actuators: Up to 2.8 bar (40 psig)
When Normally Used With Piston Actuators: Up to 10.3 bar (150 psig)
Nominal Deadband
Percent of Positioner Output Span:
2.4 mm (0.094 inch) exhaust port: 2%
9.5 mm (0.375 inch) exhaust port: 3.5%
12.7 mm (0.5 inch) exhaust port: 5%
Operative Temperature Limits
Standard: -40 to 71C (-40 to 160F)
High Temperature: 0 to 121C (32 to 250F)
Connections
Input Signal: 1/4 NPT
Supply and Output Signal: 3/4 NPT
Mounting
The volume booster is typically nipple‐mounted between the pneumatic supply source and the actuator, and may be used with piston or diaphragm actuators. Many actuators require larger casing or cylinder connections and modifications to allow the booster to deliver the higher volume output.
The booster may also be directly mounted to the actuator by using an actuator yoke mounting bracket
or casing mounting bracket.
Pressure Connections
The input signal connection is 1/4 NPT. The supply and output connections are 3/4 NPT (minimum pipe size recommended for nipple mounting is 1/2 NPT for 2625 and 3/4 NPT for 2625SST). Ensure that the
piping is of proper size to meet the capacity demands of the booster and that you equip the actuator with properly sized input connections.
Exhaust Ports
Exhaust to the atmosphere is through exhaust ports in the side of the unit. Keep the exhaust ports free of any obstructions or foreign materials that might clog them. The optional pipe away vent construction exhausts though a single 1/2 NPT port on the side of the unit.
Operating Information
The only operating requirement of the volume booster is the adjustment of the bypass restriction for stable actuator performance. Although systems with different characteristics may require different adjusting techniques, the following adjustment procedure is recommended when using the actuator for throttling control…...more
Principle of Operation of Fisher Volume Booster 2625-12:
Because of the restriction, large input signal changes register on the booster input diaphragm sooner than in the actuator. A large, sudden change in the input signal causes a pressure differential to exist between the input signal and the output of the booster. The port remains open until the difference between the booster input and output pressures returns to within the deadband limits of the booster. With the bypass restriction adjusted for stable operation, signals having small magnitude and rate changes pass through the bypass restriction and into the actuator without initiating booster operation. Both the supply and exhaust ports remain closed, preventing unnecessary air consumption and possible saturation of positioner relays.
For complete datasheet….TSP Controls – Fisher Volume Booster 2625-12 Datasheet
