Rotork plc Datasheets for Pneumatic Relays and Volume Boosters

Pneumatic relays and volume boosters control output air flow and pressure in response to a pneumatic input signal.  They can perform simple functions such as boosting or scaling the output, or use complex reversal, biasing, and math function operators.
Pneumatic Relays and Volume Boosters: Learn more

Product Name Notes
Adjustable Ration Relay -- M21 Features Adjustable from 30:1 dividing ratio to 1:30 multiplying ratio. Venturi aspiration system. Optional input and output biasing. Floating seal ring isolates control chamber. Panel or Line Mounting Benefits Assures...
High Flow Reversing Relay -- M2500A Features Control sensitivity of 1" water column. Flow capacity of 150 SCFM (255 m3/HR). Soft Supply and Exhaust Valve seats. Balanced Supply Valve. Aspirator Tube design. Separate Control Chamber. Benefits...
High Flow Positive Bias Relay -- M1500A Features Control sensitivity of 1" water column. Large Supply and Exhaust Valves. Soft Supply and Exhaust Valve seats. A balanced Supply Valve. Aspirator Tube design. A separate Control Chamber. Unit...
Positive and Negative Bias Relay -- M14 Features Control sensitivity of 1/2" water column. Balanced Supply Valve. Aspirator Tube design. Separate Control Chamber. Mounting Bracket available Canadian Registration Number (CRN) certification. Benefits Allows use in precision applications.
Reversing Relay -- M25 Features Control Sensitivity of 1/8" water column. Balanced supply valve. Aspirator tube design. Separate control chamber isolates. Unit construction. Benefits Allows for use in high precision applications. Minimizes the effects...
Snap Acting Relay -- M24 Features Control Sensitivity of 1/8" water column. Balanced supply valve. Aspirator tube design. Separate control chamber. Unit construction. Benefits Designed for use in precision applications. Minimizes the effects of supply...
500 SCFM [850 m3/HR] Forward/Exhaust High Flow No Bleed Volume Booster with Bypass Valve -- M4800A Features Cv = 9; Flow capacity of 500 SCFM (850 m3/HR). Ratio Accuracy of 0.5%. Fixed dead band between the operation of the supply valve and exhaust valve. Integral bypass...
500 SCFM [850 m3/HR] Forward/Exhaust High Flow No Bleed Volume Booste -- M4900A Features Cv = 9; Flow capacity of 500 SCFM (850 m3/HR). Ratio Accuracy of 0.5%. Very low dead band between the operation of the supply valve and exhaust valve. High...
150 SCFM [255 m3/Hr] Forward/Exhaust High Flow No Bleed Volume Booster -- M4500A Features Flow capacity of 150 SCFM (255 m3/HR). Five signal to output ratios. Control sensitivity of 1" water column. Soft Supply and Exhaust Valve seats. Separate Control Chamber. Optional remote...
Back Pressure Pneumatic Booster -- M4500ABP Features Flow capacity of 150 SCFM (255 m3/HR) Control sensitivity of 1" water column. Large Exhaust Valve design. Separate Control Chamber Aspirator Tube design. Unitized Construction. Benefits Extremely fast and...
40 SCFM [68 m3/Hr] Forward/Exhaust Flow No Bleed Volume Booster -- M2000 Features Flow capacity of 40 SCFM (68 m3/HR) Balanced Supply Valve Aspirator Tube design. Soft Supply and Exhaust Valve Seats. Small signal volume. A separate Control Chamber isolates the Diaphragm...
45 SCFM [76.5 m3/Hr] Forward/Exhaust Flow Volume Booster -- M20 Features Flow capacity of 45 SCFM (76.5 m3/HR) Ten available pressure ratios Optional Adjustable By-Pass Needle Valve option includes bubble tight exhaust valve. Optional Fixed Negative Bias. A separate Control...
Back Pressure Pneumatic Booster -- M20BP Features Flow capacity of 45 SCFM (76.5 m3/HR Aspirator tube design A separate Control Chamber isolates the diaphragm from the main flow. Unit construction. Mounting Bracket available Benefits Fast responsive...
1800 SCFM [3058 m3/Hr] Forward/Exhaust Ultra High Flow Volume Booster -- M200XLR Features Forward and exhaust flow capacity of 1800 SCFM (3058 m3/HR) Control sensitivity to 1" water column. Increased Sensitivity ("L") option. Separate Control Chamber. Optional Adjustable By-Pass Needle Valve (includes...
1800 SCFM [3058 m3/Hr] Forward Ultra High Flow Volume Booster -- M200 Features Forward flow capacity of 1800 SCFM (3058 m3/HR) Control sensitivity to 1" water column. Separate Control Chamber. Optional Increased Sensitivity configuration with larger Control Diaphragm. Unit construction. Mounting Bracket...
Positive Bias Relay -- M15 Features Sensitive to 1/4" Water Column variation. Balanced Supply Valve. Aspirator Tube. Flow Capacity of 40 SCFM (68 m3/HR). Separate Control Chamber. Mounting Bracket available. Benefits Permits use in high...
Computing Relay -- M22 Features Small bleed across relief seat. Multiple inputs available. Adjustable Bias Range from -18 to +15 psig. Two gauge ports located 90deg from supply and outlet ports. Line or Panel...
Higher Pressure Selector Relay -- M91
Lower Pressure Selector Relay -- M90
Features Small, rugged design. Soft seat construction. Low selection differential. Fast response. Automatic switching. Benefits Suitable for installation where space is limited. Assures positive shutoff. Allow precise control of switching...
Multi-Stage Positive Bias Relay -- M85D Features Two Stage Pilot Operation. 14 SCFM flow capacity in a small size unit. Low air consumption. Compact size. Available in 1/8", 1/4" and 3/8" standard port sizes. Benefits Allows...