Hydraulic Wedge Grips

Instron hydraulic wedge action grips may be used in static or dynamic materials testing applications, interchangeable wedge-shape grip faces accommodating either flat or round specimens.

The grips maintain a constant gripping force on the specimen regardless of the test forces acting upon it, as long as there is hydraulic pressure to the grips.

Principle Of Operation

Each grip functions independently of the other, an external hydraulic supply providing pressure to both open and close the grips.

When gripping pressure is applied, the relative vertical position of the specimen/jaw faces remains unchanged to prevent specimen load generation during the gripping process. 

Once the grip faces contact the specimen the hydraulic pressure produces a vertical force on the grip head. The grip force will remain constant as the design automatically compensates for specimen thickness changes.

Application Range

  • Type of loading: Static or dynamic, reverse stress. 
  • Specimen material: Metallics, plastics, composites. 
  • Specimen geometries: Round and flat section using appropriate optional jaw faces.
Item Name Capacity Cat #
Fatigue Rated Hydraulic Wedge Grips (+/- 30 kN) ±30 kN ±6800 lbf 2742-301
Fatigue Rated Hydraulic Wedge Grips (+/- 100 kN) ±100 kN ±22000 lbf 2743-401
Fatigue Rated Hydraulic Wedge Grips (+/- 250 kN) ±250 kN ±56000 lbf 2742-501
Fatigue Rated Hydraulic Wedge Grips (+/- 500 kN) ±500 kN ±112000 lbf 2742-601