UBL Compensating

The compensating type is designed to allow the jaws to clamp a workpiece at equal forces along the workpiece perimeter with respect to both center/boss holes.
2 jaw or 3 jaw structure is available. All parts except the actuator are the same with those of the Centralizing type. The compensating-type UBL Chuck offers a wide range of chucking, depending on boss and center holes.
Also, this type features excellent cost efficiency and great adaptability to complex shape cutting and high load machining, as will as high levels of accuracy and maintainability.
In addition, special jaws, fixed center, datum pin, dynamic balance adjustment, combination design, etc. can be employed according to individual customer requirements in terms of machining accuracy, cutting conditions, and portion of clamping shape.

Unparalleled high performance in the machining of castings and forgings

The UBL ball lock chuck developed by N.A. Woodworth [now FORKARDT] is an oscillating power chuck that offers unparalleled performance in the machining of die cast and forged materials. Since 1969, when we acquired the exclusive right to manufacture and sell Woodworth patented products such as its UBL and diaphragm chucks in Asia, our chucks have been used as indispensable work-holding devices in the machining of automobile parts, and our unique UBL new design has been used to meet the most difficult requirements. We are always ready to respond to your needs.

A broad chucking range allows optimum machining.

The UBL Chuck is a locking type power chuck that offers high levels of gripping performance, rigidity and durability to allow secure gripping of cast or forged materials with a draft angle and workpieces with an overhang, which conventional chucks can not grip. Also, they can improve the roundness of thin-walled parts and respond to difficult-to-grip complex-shape workpieces.

Our Designs based on original technology and know-how.

In addition to such basic types as Centralizing type (for general chucking) and Compensating type (for chucking with respect to boss or center hole), many other types such as ON-OFF (switchover type), Long Stroke, Large-Diameter Through Hole, and 6-Jaw types (for ID and OD chucking) are available as standard. Also, depending on applications, Quick Jaw, Special Jaw-actuator (base jaw), or Light-weight Jaw can be selected.Since we design the entire chuck, with safety and machining performance taken into account, reliable and comfortable operations will be ensured. * While there are many copies and similar products on the market, we always aim for the most advanced quality and performance with our long-accumulated technology, diverse repertoire, and know-how in materials, heat treatment, and processing.


  • Clamping either inner or outer diameter of workpiece is possible with the same chuck.
  • Retraction mechanism with excellent thickness accuracy and clamping stability
  • The equalizing mechanism enables chucking of uneven thickness OD parts.
  • Heavy-duty cutting of tapered workpieces is possible with a minimum gripping allowance.
  • The circular motion ensures long service life.
  • The inner parts are interchangeable.
  • The arm seal and special waterproof seal offer excellent dust and water resistance.



Phone: +81-72-923-1825