Rotation inspection instrument with measuring circles RK

Measuring balls

The RK (former URM-K) measuring instrument is a flexible device to inspect profiled shafts and wheels.

Probing is carried out via two large balls and is based on double flank contact. The traditional place for the URM-K is on the shop floor directly next to the production machine. This location is ideal for quick and reliable sampling inspections.

Features and Application areas:

  • Quick determination of gear features such as dimension, concentricity, pitch and tooth curve. Approx. 1 minute per gear profile

Shaft of utility vehicle

  • Diameter inspection for size, concentricity and roundness
  • Calculation of axial references on diameters and gearing to determine the positional deviations
  • Measuring constant velocity joints
  • Highest precision through substitution methods (calibration on a setting master) and available axis compensation
  • Measuring balls from dia. 1 to dia. 25 mm and measuring pins
  • Automatic 6-fold measuring ball change
  • Temperature compensation available for device and workpiece

Automatic turrent

  • Easy to use, manual or fully automatic
  • Very little set-up requirement
  • Very robust design, to be used on the shop floor directly next to the machine tool
  • Link between production and inspection room
  • Simple and freely programmable system
  • Documentation of the measuring results for process control with various interfaces: QS-Stat ®, Transferformat, csv® format, pdf® format etc.

RK horizontal

  • Customer specific adaptations of mechanics and software
  • Interlinked usage within automation for 100% inspections is possible

RK vertical


The RK is available with different options. Horizontal instruments are ideal for the inspection of shafts up to a length of 800 mm. Instruments with a vertical spindle are ideal for the inspection of wheels and joints up to a dia. of 300 mm. We are happy to advise you on and supply you with tailor-made instruments for your requirements.

The following are examples of measuring tasks and measuring geometries already implemented:




    Bevel gear

    Tooth position

    Plane surfaces

    Ball track


    Internal gear

RK measuring instruments are suitable for workpieces with tolerances (Tmin) of 20 µm or larger. We offer various types of proof of the measurability, according to customer requirements.


The design of the RK software is very functional. All required information is clearly laid out on the graphical display. This enables the operator to identify the current measuring location easily and whether the workpiece has passed the inspection or not.

Interfaces for databases and QS-Stat® are available.