Hexalobe Gages

Thread Check Inc. offers a complete range of hexalobular plug gauges, hexalobular ring gauges, and digital hexalobular penetration gauges for inspecting the hexalobular internal and external driving features for bolts and screws. Thread Check offers recess sizes from T6 – T100. Custom sizes are priced on request.

ISO 10664:2005E specifies the shape and basic dimensions of the hexalobular internal driving feature for bolts and screws including the gauging method.

The curvature of the contour of the hexalobular internal driving feature is defined by the gauges specified in the Limit Size and Diameter tables of the standard (Tables 3, 4, and 5). The contour at the bottom of the socket beyond the gauge is an optional feature. 

The hexalobular Go gauge should freely enter to the penetration depth as specified in the standard. The NoGo hexalobular gauge should not enter to the depth greater than the standard’s specified fallaway allowance.

All hexalobular gauging is taken with reference from the top surface of the head. If the head is round or oval, then measurements are taken from the top surface of where the head and the hexalobular counterbore intersect each other.

Digital and dial hexalobular penetration gauges should be adjusted or set to zero while the gauge is pressed against a flat surface thus compressing the plunger to make it flush with the gauge reference surface.

A plain NoGo gauge with a diameter as specified in the standard should also be used. The plain NoGo gauge should not enter the hexalobular internal driving feature to a depth greater than the fallaway allowance as specified in the standard. Details regarding gage and fallaway dimensions can be found in ISO 10664.

Thread Check’s sales engineers can assist you with all your hexalobular gauging requirements.

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