STANDARD TEST – PITTING RIG – THREE DISCS ON ROLLER







  • Description

    The ST-PR Pitting Rig features a three-disc-on-roller configuration designed to investigate RCF
    failure mechanisms, including macro and micro pitting in rolling-sliding contacts under both dry
    and lubricated conditions. The test roller specimen is driven by a single motor, utilizing a
    circulating torque mechanism with gear pairs, which eliminates the need for high-capacity drive
    motors. Different Slide Roll Ratios (SRR) are achieved by selecting the appropriate gear pairs
    and/or varying the diameters of the discs and test roller.

    Load is applied via a pneumatic cylinder action on the top disc, which is mounted on a floating
    shaft. A precision pressure transducer is used to indicate the load, which is then transmitted to
    the test roller, which is also mounted on a floating shaft. Finally, the load on the test roller is
    transmitted to the lower discs, which are mounted on fixed shafts.
    A load cell reacts the horizontal force acting on the upper disc, which is generated by traction
    between the test roller and the upper disc.
    The two lower discs are electrical insulated and fitted with brushes, allowing electrical contact
    measurements between each disc, through the contacts with the roller specimen.

    Test Configurations

    Various disc and test roller geometries can be used to achieve different Hertzian contact pressures
    and slide-roll ratios. Test speeds are controlled through a high-speed motor spindle with a
    frequency inverter to achieve the desired surface velocity of the discs and rollers. The test
    temperature is regulated via a lubrication circulation system with a temperature-controlled
    feedback mechanism.

    Order As:

    ST-PR PITTING RIG – THREE DISCS ON ROLLER

  • Technical Specifications

    Size of 3 Discs: 62 to 75 mm diameter (each) – can be varied
    Size of Test Roller: 25 to 38 mm diameter – can be varied
    Load Range: 0 to 2,000 N
    Loading Method: Pneumatic
    Load Measurement: Pressure transducer
    Load Control: Manual precision pressure regulator
    Traction Force: Load cell
    Contact Resistance: Lunn-Furey circuit or LCR circuit
    Slide Roll Ratio: 0 to ± 30 % – can be varied
    Surface Velocity of Test Roller: up to 12 m/s
    Wear Analysis: Optical Screening
    Rotational Speed of Test Roller: up to 6,000 rpm
    Temperature Range: Ambient to 150°C
    Temperature Sensor: k-type thermocouple
    Motor: 1.5 kW a.c. vector motor with liquid cooling
    Control & Data Acquisition: PC with COMPEND software and USLIM interface

    Automatically Controlled Parameters

    Rotational Speed
    Lubricant Temperature
    Test Duration

    Manually Controlled Parameters

    Load
    Slide-Roll Ratios
    Lubrication Flow Rate

    Measured Parameters

    Rotational Speed
    Load
    Traction (upper disc – test roller)
    Electrical Contact Resistance (lower disc – test roller – lower disc)
    Vibration Signal (uncalibrated)
    Temperature
    Test Duration

    Services

    Electricity: 230 V, 6.4 A, 1.5 kW

  • Download the Machine Leaflet