Runout Testing

Smooth operation of rotating machinery requires shafts with only little runout.

Runout is a measure for the imperfections of a rotating shaft to be ideally round (radial runout) or flat (axial runout). Runout will be checked during manufacturing or repair of a rotating shaft. For that purpose Hofmann offers portable equipment or stationary machines.

Portable Runout Testing System

Type RO 7000

Hofmann’s Portable Runout Inspection System RO 7000 provides a solution to measure radial and axial runout of rotors and other cylindrical parts in multiple axial planes. During a measurement a rotor will be supported for example in a lathe, in V-blocks or on rollers. Rotors may be rotated by a motorized drive or manually. The system consists of a measuring controller to be hooked-up to a PC, a sensor set and the measuring software Orbistar 2.

Orbistar 2 helps to setup a specific measuring task, acquires and displays the measuring data, provides tools for data analysis and generates reports. This software can also compensate for systematic measuring errors of typical rotor bearings like V-blocks and for the shaft movement using a reference sensor.

Runout will be measured using proximity sensors which provide adaptors with interfaces to standard magnetic bases. The angular position will be captured with an encoder wheel which is driven by the rotor surface or by a speed sensor.

A special feature of RO 7000 is its capability to measure electrical runout simultaneously with a tactile (mechanical runout) and an eddy current senor (total runout). The electrical runout is the difference between the total and the mechanical runout, i.e. the systematic measurement error of the eddy current sensor. This measuring value is useful when inspecting traces used for shaft vibration measurements.

Special features

  • Measuring of radial and axial runout
  • Measuring of mechanical and electrical runout
  • portable system for universal application
  • flexible und simple handling
  • compatible with Hofmann’s stationary Runout-Testing-Machines UHR
  • Measuring software Orbistar 2
    •  simple and intuitive Windows software
    • ad-hoc or offline measuring setup programming,
      data analysis and report generation
    • simple exchange of measuring data between Orbistar users
    • csv-file data export
    • compensation of systematic measuring errors of
      typical bearing setups
    • compensation of lateral and axial rotor axis movement
    • display of measuring values as x-y or polar diagram
      or as 3D diagram with multiple polar diagrams each
      referenced to an axial rotor coordinate
    • analysis of measuring data including order analysis, eccentricity etc.
    • report templates editable to suit customer-specific requirements


  • Measurement of radial and axial runout of rotors in
    • manufacturing
    • maintenance, repair and overhaul
  • Measurement of
    • mechanical runout
    • total runout
    • electrical runout
    with precise angular reference
  • Checking of the runout of measuring traces used for monitoring shaft vibrations acc. to ISO 20816-1, API 610, API 612, API 617 or API 687