The Powerpack is an actuator that controls a load such as a valve.
As its output shaft performs rotary motions it is suitable for controlling a final control element of rotary type such as a butterfly valve.


The Powerpack is a kind of an electro-hydraulic actuator.
It is of the proportional positioning type and has a hydraulic work piston that is proportional to the electrical system, with the function of converting a DC electrical signal (DC 4-20mA) into a motion of the hydraulic work piston.
The Powerpack is of a structure that unitizes the current-hydraulic pressure converter unit, the hydraulic pump and the work cylinder, and it does not require external piping.


  • Usable as an actuator for various electronic controllers.
  • The actuating speed is high and a large actuating force can be obtained because actuation is performed by using hydraulic pressure on reception of an electrical signal.
  • Maintenance is easy and reliability is high because of a moving coil system incorporating a hydraulic jet pipe and a stable permanent magnet.
  • As the casing serves as an oil tank and all parts are contained in the interior, no external piping is required.


The Powerpack consists of an electro-hydraulic converter, a hydraulic unit, a crank unit and a work cylinder. All of these components are installed in an oil tank made of cast iron.



Common Specifications

Input signal 4 – 20mA DC
Resistance of moving coil 470Ω+0Ω/-50Ω(at25˚C)
Floating band 1.50%
Linearity ±2%
Maximum crank arm rotation 60 degrees
Length of crank arm 300mm
Control action Proportional action Operating direction
Normal: Crank arm turns counterclockwise with input signal up.
Reverse: Crank arm turns clockwise with input signal up.
Installation Horizontal
Hydraulic oil temperature +10 – +70˚C
Paint color Silver

Specifications by model

Model AJ11(50HZ) AJ11(60HZ) AJ21 AJ41
Motor 0.4 0.4 0.75 1.5
Max.Operating torque (kN·m) Max: 1.42
Min: 1.02
Max: 2.15
Min: 1.23
Max: 2.15
Min: 1.53
Max: 4.12
Min: 2.95
Max.speed with no load degree (°/sec) 2.4 7 8.5
Max. operating pressure (MPa) 1 1.2 1.2 2.3
Jet pipe hydraulic pressure (MPa) 1 1.2 1.2 0.8
Diameter of jet pip (mm) 2.0 1.6 1.6
Auxiliary piston None width CV2 width CV2
Cylinder dia.x stroke (mm) Ø125×150 Ø125×150 Ø125×150
Hystresis error (no load) (%) 1 1 1
Overshooting (no load ) (%) 1 1 1
Amount of oil required (ℓ) 27(w/ACC:34) 27(w/ACC:34) 27(w/ACC:34)
Hydraulic pump type Fixed Variable
Rotating direction of motor Revers Normal
Ambient temperature(°C) -20~+55 -20~+55 -20~+60
Mass. (including hydraulic oil) (kg) 175 180 195

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