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Hydraulic actuator is the main component in hydraulic power steering system of tractors
and other hydraulic machinery. These actuators must be inspected to an acceptable
level through an efficient inspection machine in order to prevent mechanical failure.
Previous studies have shown that actuators with end of line quality testing perform
well and enhance reliability and durability. Previous studies on analyzing industrial
products through automated inspection machines make a significant contribution in
the development of these products. In this research project , we have develop a fully
automated hydraulic actuator test rig for hydraulic cylinder manufacturers for end of line
quality testing. A series of advanced control valves combined with intelligent algorithm
have been employed to measure the key performance parameters. Two external actuators
have been connected with the central work piece actuator to enable the cylinder to cycle
against an external load sufficient to maintain a constant operating pressure of 140 bar
for 90,000 cycles. This will enable actuator to perform accordingly as per standard
requirement in which total leakage shall not exceed 50ml/90,000 cycles. Hydraulic
gear pump is used for fluid flow in the circuit. Hydraulic Pump is connected with
eclectic 3-phase motor through couplings to transfer the hydraulic oil in hoses. Solenoid
directional control valves, pressure distributor valve and pressure relief valves were used
for maintaining the hydraulic oil pressure at 140 bar during endurance testing. Another
test namely performance test has been performed on the hydraulic actuator in which
piston keeps in between 25 mm and pressure on one side of the piston keeps at 240 bar
for 1 minute and then pressure reduces to zero and than again pressure increases to 20
bar for 5 minutes. Same procedure was repeated on the other side of piston. Standard
for this test requires no external leakage and internal leakage is set to be not exceeded
than 5ml/minute during pressure test. Results of endurance test shows that leakage was
not exceeded than 50ml/90,000 cycles. Results of performance test shows no external
vi
leakage and internal leakage was not exceeded than 5ml/minute. The project research
present an effective procedure to quality check hydraulic actuators with proof of the
concept to actuators manufacturers. The new procedure is a significant improvement
towards manufacturing more reliable actuators