Principle of Operation

Cord capstan grips provide a superior method for clamping twisted or braided cord during testing. Each grip has a round capstan with a right-hand spiral grooved surface that accommodates specimens up to 3.2 mm (0.125 in) in diameter. The capstan is split axially into two halves, one half being stationary and the other movable. The specimen is wound from the outside of the capstan towards the center before being passed through the split halves where it is clamped. The groove completes 2.5 turns around the capstan, which allows two full turns for distributing the specimen load and stress concentration. The grips self tighten as load is applied to the specimen.

Smooth capstan surfaces are available separately.

Application Range

• Type of loading: tensile, static only
• Specimen materials: twisted or braided cord
• Specimen shapes: cord or strips