Torque Definitions

Accreditation – To certify an institution as meeting all formal official requirements and to grant approval for meeting the requirements

Accuracy – The closeness of agreement between a test result and the accepted reference value [see also precision and trueness]

Adjustment – To bring the components of into a more effective or efficient calibration or state

Bi-Directional – Torque tool can be operated in either a left or right hand direction and still have the clutch click out when torque value is reached

Calibration – Set of operations that establish, under specified conditions, the relationship between values of quantities indicated by a measuring instrument or system and the corresponding values realized by standards.

Calibration Interval – The intervening time between the performing of calibrations.

Drift – A slow change of a metrological characteristic of a measuring instrument

Hysteresis - The lagging of an effect behind its cause

ISO 17025 – An ISO standard specifically written for calibration laboratories

Parallax – (Greek: παραλλαγή (parallagé) = alteration) is the change of angular position of two stationary points relative to each other as seen by an observer, due to the motion of said observer. Or more simply put, it is the apparent shift of an object against a background due to a change in observer position.

Resolution – The smallest unit that the person measuring can be expected to discriminate from the graduations. 

Tolerance – Percentage of potential inaccuracy the wrench is allowed by manufacturer (example +/- 4% CW & +/- 6% CCW, or other percentages)

Torque – Generally characterized as a turning or twisting force. Specifically defined Length times (multiplied by) Force

Torque Adjustment Range - Range over which a torque tool can be adjusted from the rated torque to the lowest mean torque recommended by the manufacturer.

Torque Range – High and low settings of a tool or the range of setting with the ± accuracy included