Efficiency and contamination test bench for pumps
Pumps are an essential part of any hydraulic system. The efficiency of hydraulic displacement units is an important parameter and depends on the operating point. The efficiency is determined by measuring the parameters pressure, flow rate, speed, torque and temperature. The pulsation of a pump is also a highly relevant parameter. By
using a RALA, a precise measurement of the pulsation is possible.Contamination can cause failure of hydraulic components due to wear. By adding test dust, the influence on pump performance and their wear behaviour can be investigated.
Test bench design
The pump and contamination test bench enables the investigation of hydraulic displacement units such as axial piston, gear and vane pumps. The hydraulic load is applied by a load valve. A torque measuring shaft is located between the electric motor (drive) and the test pump, as well as a rotational speed sensor. Furthermore, pressures and temperatures are measured in the suction and high-pressure lines of the pump. The test setup is very modular and thus allows a large number of tests with short changeover times. If, for example, the flow rate is also measured, the pump efficiency can be calculated.
Using an existing low-reflection line terminator (RALA), pump pulsation can be investigated. The test rig can also be modified to allow contamination of the oil, so that contamination tests can be carried out on displacement units. For the contamination test, test dust with a standardized particle size distribution (e.g. Arizona test dust or ISO-MTD) is introduced into the oil. After the test has been carried out, the surface changes of the components can be examined in the surface measurement room of the ifas and thus the wear phenomena caused by the introduced contamination can be investigated.
The test stand has a speed-controlled electric motor with a power of 100 kW. The maximum speed is 3000 1/min. The torque measuring shaft between drive motor and displacement unit measures torques up to 500 Nm. The pressure range of the test rig extends up to 315 bar. The delivered volume flow of the pump is optionally continuously resolved by a volume flow sensor in a range from 0.6 to 160 l/min. In addition to the delivered volume flow, other volume flows can be measured, such as the volume flow required to supply the pump controller or the leakage volume flow from the pump housing. In addition, the test stand is equipped with an effective cooling system that allows tests to be carried out at constant temperatures. Optionally, the oil can be filtered in the return flow to the tank.
Research projectsCopyright: © ifas
In the past, various research and industrial projects were carried out on the test rig. These included efficiency measurements with different fluids as part of the „BioHydra“ research project (development of a biopolymer-based hydraulic fluid with plant-based anti-corrosion additives), as well as contamination
investigations or measurements of pump controllers in the „Regelor-gane“ project (control elements for variable displacement pumps with systematic avoidance of continuous bypass losses).