Kingsbury R&D Bearing Test Lab News

The Kingsbury R&D laboratory high speed test rig (HSTR) is presently undergoing significant upgrades which will expand our journal bearing test capabilities as well as prevent test rig bearing failures due to unplanned power outages.

The existing test rig can only accommodate 5" journal bearings with L/D ratios less than 0.5. In order to significantly further our understanding of journal bearing performance, we are converting the high speed rig to be able to test journal bearings at length-to-diameter (L/D) ratios as large as 1.0; additionally, we will be able to test 4, 5 and 6 shoe journal bearings of different sizes. The new rig can also test load-between-pad (LBP) and load-on-pad (LOP) bearing configurations without requiring the bearing orientation to be physically changed. The current method of changing bearing orientation involves opening the bearing housing to reposition the test bearing, which adds time to each test series.

Additionally, recent unplanned power outages have resulted in costly test rig bearing failures due to loss of supply oil flow from the main lube pump. In order to prevent this occurrence in the future, an emergency lubrication system consisting of a 120 gallon hydraulic accumulator, servo control valves, and an automatic load dump switch are being installed along with the new test rig. The hydraulic accumulator functions as a pressurized reservoir that can supply lube oil to the bearings for a short period of time in the event of a complete power outage or loss of main lube pump pressure. The servo valves provide remote control of supply oil flow to the bearings, allowing the flow rate to be rapidly adjusted as needed during emergency situations to ensure adequate oil supply to the bearings. The automatic load dump system utilizes a pressure switch at the discharge of the main lube pump. If the main lube pump pressure drops too low, the switch triggers a solenoid valve to open, immediately relieving the pressure in the bearing load applicator hydraulic lines.

Commissioning of the new test rig, dubbed the Wide Journal Test Rig (WJTR), and the emergency lubrication system is planned for early October. R&D would also like to extend our thanks to all the departments that helped make this upgrade possible.

Figure 1. Inventor Model of Wide Journal Test Rig

Figure 2. Wide Journal Test Rig (with upper half removed)

Figure 3. Servo Valves

Figure 4. Hydraulic Accumulator