The Length Comparator, w/Invar Bar, and Dial Indicator, is used for measuring length changes in 10in (254mm) specimens cast with special gage studs in the ends to fit the bottom and top anvils of the Comparator. Sensitive indicator with 0.0001in (0.0025mm) divisions measures specimen length.
Length Comparator, Dial Indicator, has a 0.4in range mechanical dial indicator, which will convert to time-saving digital version with purchase of a digital indicator. Includes a heat treated, hardened Invar Reference Bar for exactly zeroing the dial indicator at regular intervals. Construction is a sturdy upright support attached to a solid base. Test specimens up to a 4x4x10in (102x102x254mm) cross section, but 1x1x10in (25x25x254mm) prisms are normal.
Methods are applicable to testing of hardened portland cement paste, mortar, concrete, or evaluation of hydraulic hydrated lime for structural purposes.
Overall Comparator Dimensions: 11x11.5x17in (279x292x432mm), WxDxH.
Meets Test Methods:
ASTM C 151
ASTM C 490