pneumatic chuckGMT – PNEUMATIC CHUCK

Firstly, The design of the Pneumatic Chuck utilises in full, the spindle bore for bar/pipe work. This design avoids rear mounting of the actuating cylinder and necessary draw bar connections. The chuck mounts on the lathe spindle with an adaptor flange. Furthermore, the stationary air distribution system with the ports to supply air to the respective sides of the piston is separate on the chuck.

These power chucks are available in various sizes ranging from size 160mm Ø to 1000 mm Ø. Also, we offer chucks with standard jaw stroke of 4.2mm to 12mm and extended jaw stroke of 19mm to 25.4mm. The extended jaw stroke to hold pipes, casings and tool joints.

For holding long oil pipes, one chuck operates on the front end of the spindle, and one chuck at the near end of the spindle. Pneumatic Front End Chucks have twin non-return valves. This prevents the clamping air from returning through the port unless air comes in on the other side of the piston. This ensures retention of clamping force even when the air supply switches off. The maximum operating pressure of the chuck is at 10 bar pressure.

Principle of Operation

Power Operated Pneumatic Front end Chuck has two special rubber seal rings on the distributor assembly. The special seal ring compresses when the chuck pneumatically actuates to facilitate opening and closing of chuck jaws. Once the job clamps due to venting of the air supply, the special seal rings lift to ensure rotation of the chuck. This design eliminates wear on the special seal rings.


The power chuck body is made of forged medium carbon steel. The guideways are flame hardened and ground. Besides, the wedge and base jaws are of nickel chrome steel; case hardened and ground on all working surfaces. Serrations are provided on top face of the base jaws are ground. As a result, the various radii on the hard jaws in conjunction with serrations grip a wide range of job diameters.

Electro Pneumatic Control Unit

Each GMT Pneumatic Front end Chuck comes with an Electro Pneumatic Control Unit. This control unit consists of Lubro Control Unit, Electrical Contactors, and Fuses and in addition, solenoids for interlocking with the main spindle.

Besides, push button or foot switch comes with the Electro Pneumatic Control Unit for actuating the chuck.


  • Pneumatic front end chucks utilise in full, the spindle bore for bar/pipe work
  • This design avoids rear mounting of the actuating cylinder and necessary draw bar connections
  • The actuating cylinder is built-in the chuck
  • The stationary air distribution system is separate on the chuck
  • Power operated pneumatic front end chucks have twin non-return valves

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