Tork-Mate^™ Pneumatic Actuator

890 Series

Heavy Duty
Rack and Pinion
Extended Life…
Up to 15 Million Cycles

Advantages

The Tork-Mate 890 series extended life actuators are ideal for the operation of 90° turn devices such as butterfly valves, ball valves, plug valves, damper valves and other devices. Tork-Mate pneumatic actuators have features that are unique, providing many benefits to the user looking for worry-free service.

TMHC 2324

A proprietary two-step hardcoat process that offers superior protecion on interior and exterior housing surfaces. TMHC 2324 also ensures maximum life from the piston seals, piston bearings and heel bearings.

NAMUR Mounting

Tork-Mate 890 series actuators meet the latest NAMUR standards, allowing direct or close coupling of NAMUR designed accessories. The pinion interface features a positive, international standard drive for positioners, switches and other accessories. The solenoid interface allows direct acceptance of any NAMUR designed control valves.

Modular

Easily removable end caps and modular spring packs simplify the conversion from double-acting to spring-return configurations.

Travel Adjustment

The Tork-Mate 890 series actuators feature pinion travel stops that allow a full +/-10° of valve travel adjustment. As an option, extended stroke adjustment screws can be added for inexpensive throttling applications.

Extended Cycle Life

Special piston seals provide greatly extended life compared to standard O-ring actuators. All other bearings, seals and components have been engineered to provide superior and extended service lives.

Blow-out Proof Pinion Gear

In addition to the stainless steel pinion retaining ring, the Tork-Mate 890 series actuators feature a unique internal safety bar.

Operating Ranges

Tork-Mate 890 series double-acting actuators produce guaranteed minimum torque outputs up to 17,466 inch pounds (1973 Nm).

Custom Options

These include Viton^® seals, high temperature trim up to 250° F (121° C), special finishes, stainless steel pinions, special mounting configurations and special coupling configurations.

Imperial or Metric Mounting

Operation Principles

Double-Acting
For clockwise operation, Port 2 (P2) is open to atmosphere and air pressure is directed to Port 1 (P1). As the pistons move apart, the pinion rotates clockwise. The linear movement of the pistons is converted to rotary motion by the piston racks and the output pinion gear.

For counter-clockwise operation, Port 1 is open to atmosphere and air pressure is directed to Port 2.

The pressure differential moves the pistons together, rotating the pinion counterclockwise.

Spring Return
For clockwise operation, Port 2 is open to atmosphere and air pressure is directed to Port 1. The air pressure compresses the springs and moves the pistons outward. As the pistons move apart, the pinion rotates clockwise. The linear movement of the pistons is converted to rotary motion by the piston racks and the output pinion gear.

For counter-clockwise operation, Port 1 is open to atmosphere and air pressure is directed to Port 2. High pressure and/or spring force moves the pistons inward, rotating the pinion counterclockwise.

Design Features

1. Piston
Aluminum alloy, designed for the most demanding applications.

2. Piston bearing
Low friction wear band centers the piston for extended life.

3. Piston Seal
A double acting, PTFE, O-ring energized seal minimizes friction and requires an extremely low breakaway force. Provides a much longer life than conventional O-rings.

4. Pinion
High strength steel, plated for corrosion resistance. Precisely machined gear minimizes wear and backlash.

5. Piston Rack
Precision engineered tooth profile and wide engagement with pinion minimizes wear and maximizes strength. An integral safety bar* prevents any possible pinion blowout.

6. Pinion Bearings
A proprietary high wear, low friction acetal compound extends life.

7. Pinion Seals
Nitrile, specially lubricated for life.

8. Lubrication Groove
Unique lubrication groove between the piston seal and piston bearing holds the proper amount of grease where it is needed for maximum life.

9. Thrust bearing
Designed for maximum life.

10. Fasteners
304 stainless steel are high strength and corrosion resistant.

11. End Caps
Special aluminum alloy for durability. Powder coated for corrosion resistance and durability. Optional spring return end caps have restrained springs for easy installation.

12. Housing
Extruded aluminum alloy, precision machined with a proprietary hard coat finish internally and externally to guard against wear and corrosion.

13. Piston Heel Bearing
Large acetal bearing controls gear backlash and eliminates rack fatigue.

* Model 5000 and 11000 feature interlocked tooth geometry to prevent pinion blowout.

General Dimensions

Imperial

Metric

Imperial

Metric

Performance Data

Double-Acting – Imperial

Double-Acting – Metric

Spring Return – Imperial

Spring Return – Metric

Torque Ratings

Double-Acting – Imperial

Spring Return – Imperial

Double-Acting – Metric

Spring Return – Metric

Tork-Mate Pneumatic Actuator Series 890 Bulletin – English

Tork-Mate Actionneurs Pneumatiques Série 890 Bulletin – Français

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