Torque Meter Frequently Asked Questions

(1) Coupling and centering
The coupling alignment accuracy will vary depending on the rotational speed used and the type of coupling, but it should be within 0.05 mm (TIR = Total Indicator Reading - the difference between the maximum and minimum measured values).
Use a flexible coupling. If the coupling with the connected equipment is not properly aligned, a large bending load may be applied to the detector's axis, potentially damaging the bearing or causing the axis to break.
When the load caused by misalignment is large due to the spring constant, strive for the highest possible alignment accuracy, even within the allowable dimensions. Also, if an abnormal noise is heard from the coupling, realign it to eliminate the noise. Pay attention to increasing the alignment accuracy as the rotation speed increases.
The thrust load should be limited to approximately the coupling mass.
Also, see TorquemeterFAQ here Coupling and alignment work See also "[...]."

(2) Selection of couplings
The mass of the coupling to be attached to the detector is determined by the maximum rotational speed used. Please refer to the curve corresponding to the detector rating in the table below when making your selection.

Coupling manufacturers offer a variety of shapes and characteristics. The diagram below shows an example for applications with a rotational speed of 4000 r/min or less.
When using at rotational speeds of 4000 r/min or higher, attention must be paid to dynamic balance, eccentricity, and angular misalignment. For relatively small-capacity detectors, non-magnetic materials are recommended to avoid magnetic interference. For further details, please contact the coupling manufacturer.
We can also supply couplings as a set, so please feel free to use our service.

(3) The "fitting" of coupling
When coupling to the shaft end, use an interference fit. A clearance fit will cause corrosion at the shaft end, altering strength and mechanical dimensions, and potentially leading to breakage. Typically, the interference fit is 5D/10000 to 1D/1000 relative to the shaft end diameter D. Apply a lubricant such as molybdenum dioxide to the mating surfaces.