Tri-axial Joint meters Model SME 2250 electrical type and SME 2251 mechanical type are generally available in 0 -25 mm or 0 -50 mm ranges. These are very rugged in design and the system basically comprises of two base plates placed one on either side of joint or crack. One reference block is mounted on one block and a measurement head on the other base plate. Measurement head can accommodate three sensors one each for each axis measurement. For mechanical measurement the same can accommodate dial gage for measurement .Vibrating wire sensor is basically comprises of element with spring loaded gage wire which when pulled to a definite distance increase tension on gage wire which in turn changes its length vice versa changes wire’s natural frequency. Sensing wire is made to vibrate by a pulse magnet through vibrating wire readout Model SME 2460-P. The readout reads and indicates data in frequency or time period or direct in engineering units i.e. in millimeters. From protection point of view a heavy steel cover may be provided over the complete assembly.