The NRC Aerospace Research Centre's Tribology capabilities include:
- investigation of steady‑state and dynamic performance of journal bearings using unique test facilities and a state‑of‑the‑art computer modelling for plain and tilting pad bearings
- performance evaluation of high‑speed rolling‑element bearings
- diagnostics, prognostics and health management (DPHM) for rolling-element bearings and gears
- experimental investigations of steady-state and dynamic performance of gas foil journal bearings
- evaluation of materials for honeycomb and abradable seals
Abradable Seal Rig
The test rig simulates operational wear using a bladed disc that is driven by an air turbine. Axial and radial movement of the fixtured test sample is controlled by a dual-axis incursion system; incursion rates between 2.5 μm/s and 760 μm/s are possible. The maximum blade tip speed is 425 m/s.
Rotational speeds and incursion rates are determined by the test specification. Rotational speed, incursion rate, incursion forces and rub temperature are recorded by a data acquisition system. Post‑test the erosion of the seal is measured and recorded, along with test blade material loss. Normally the test samples are returned to the customer for further investigation at their facility.
High-Speed Rolling-Element Bearing Rig
The test rig features an overhung, simply‑supported shaft and is capable of speeds above 35 krpm with test bearing radial loads as high as 4.5 kN. The rig is powered by a 22 kW hydraulic motor, through a belt-and-pulley system. Radial load is applied using a hydraulic ram by way of an overhead cable‑pulley system. The bearing under test is located at the overhung section of the shaft and can be lubricated via jet or under-race.
Rotational speeds, loads and oil flow rates may be held constant or varied dependent upon the test specification. A telemetry system permits the measurement of inner race bearing temperatures. Bearing load, race temperatures, power loss and accelerations are monitored and recorded by a data acquisition system.
Journal Bearing Dynamic Rig
The test rig features a simply‑supported, rotating shaft and a free‑floating test bearing housing located at the shaft midspan. A 37 kW variable speed electric motor, driving through a belt-and-pulley system provides shaft speeds of up to 16.5 krpm. Static load is applied hydraulically through a spring‑isolated cable‑pulley system and two orthogonal electromagnetic shakers apply dynamic loads to the stator. Each shaker is connected to the test bearing housing through a flexure that ensures that the test bearing housing is unconstrained in directions perpendicular to the shaking force.
Rotational speeds and loads may be held constant or varied, depending on the test specification. Bearing load, position, acceleration, power loss and metal temperature(s) are monitored and recorded by a data acquisition system.
Oil-Free Bearing Rig
The test rig features a simply supported shaft with a test bearing surface 0.2 m long and 0.07 m in diameter and is capable of operating at speeds up to 60 krpm. The test rig also has the capability of both steady‑state and dynamic testing with loads up to 3.5 kN. Test bearing operating characteristics such as temperature, friction force, shaft orbit, and vibration are recorded by a high speed data acquisition system, enabling in‑depth data analysis.
The facility is used to evaluate bearings that use air as their medium of lubrication. Rotational speeds and loads (static or dynamic) may be held constant or varied depending upon the test specification. Bearing load, position, acceleration, power loss and temperature(s) are monitored and recorded by a data acquisition system.
Journal Bearing Static Rig
The test rig features a fixed shaft supported on tilting‑pad journal bearings and a free‑floating test bearing housing located at the shaft midspan. A 110 kW variable speed electric motor, driving through a belt-and-pulley system provides shaft speeds of up to 16 krpm. A hydrostatic loading system creates a frictionless environment between mating surfaces, permitting the transfer of high loads to the test bearing while still allowing the capability of measuring rotational friction losses.
Rotational speeds, loads and oil flow rates may be held constant or varied dependent upon the test specification. Bearing load, position, power loss and metal temperature(s) are monitored and recorded by a data acquisition system.
Traction Motor Bearing Rig
The test rig is capable of testing full‑size traction motor bearings under the severe operating conditions inherent in rail. It features a fixed shaft supported on pillow‑block bearings. Four hydraulic cylinders are connected to the bearing housing through double flexure pivots and generate a maximum radial load capability of 182 kN. This load is applied at an angle of 20° from the vertical. A 110 kW variable speed electric motor, driving through a speed reducing belt‑pulley system, provides shaft speeds up to 600 rpm.
Rotational speeds and loads are typically held constant and bearing performance is evaluated based on operating temperature and power loss. Key parameters are monitored and recorded by a data acquisition system.