Endurance testing refers to tests typically done to find out whether an assembly or a component, or a system can withstand the processing load for a long period. Endurance tests are used mainly to measure the response of a tested element under potential simulated conditions for a specific period and for a certain threshold.
Hydraulic swivel endurance testing involves examining a hydraulic swivel while it withstands varying pressure loads during rotations, and monitoring and measuring the specified parameters under such conditions for every cycle. Knowing that hydraulic swivels reach hundreds of thousands of rotational cycles, characteristics are critically important, ensuring the hydraulic swivel runs for thousands of hours will last under the conditions of varying pressurizing cycles and temperatures, the UEA hydraulic swivel endurance test stand will help ensure the product is built to last.
UEA built an in-house hydraulic swivel endurance test stand through integrating structure design, driving mechanism, hydraulics, electrical and electronic controls, computer program, and safety measures. The test procedure strictly follows the customer specifications. The brief summary of the hydraulic endurance test stand specifications and capability is listed below. Figure 1 shows the current running hydraulic swivel endurance test stand.
Figure 1- Hydraulic swivel endurance test stand.
Specifications of the Hydraulic Swivel Endurance Test Stand
Rotation Speed and Torque Capability: Rotation speed is adjustable, up to 20 rpm in both clockwise and counter clockwise directions. Maximum rotational torque can reach 1500 ft. lbs.
Hydraulics: Three different hydraulic test pressures can be applied simultaneously. Each of the hydraulic testing pressure levels can be programmable.
Electrical Controls: Push buttons to start the electrical motors, monitoring status LEDs on the control panel to display the test stand status.
Control Software: The PC-based control software was developed to command the test process, drive ON/OFF solenoids and proportional pressure control valves, monitor the test stand status, and record the test data. The test pressure profile and the cyclic sequence completely comply with customer specifications. Figure 2 shows the programming control interface.
Figure 2 – Program control interface for running endurance test.
Measurements and Data Acquisitions:
- Three pressure transducers to acquire the applied test pressures
- Rotational torque (clockwise and counter clockwise) measuring
- 12 thermocouples to record internal swivel seal groove area temperatures
- Swivel rotation speed monitoring
- Test oil cleanliness ISO4406 codes through an ICM unit
- Real time test data display on the control interface
- Cycle test data directly saved into Excel spreadsheets (shown in Figure 3)
Figure 3 – The format for test data saving.
In addition, the endurance test stand is designed to have the cold soak capability to lower the swivel temperature to -40°F, in order to check its cold starting performance.
Bo Li, CFPE