Testing the actuator

SPECIAL PRECAUTIONS

To avoid physical injury and damage to the equipment:

Read the installation, maintenance and repair procedures in the Repairs and Maintenance Manual.

WARNING

To avoid injury and damage to the product:

Hold the product down fi rmly on a grooved work platform or in a vice.

WARNING

Fluid projections:

Contents under high pressure. Wear approved eye protection. Be careful when removing plugs and connections. Detecting an internal leak in the actuator

If the actuator is fi tted with a balancing valve, plug the valve’s holes. Connect the hydraulic lines to the holes in the casing. Bleed the air from the actuator (see Installation and bleeding, page 25). Turn the shaft at 210 bars (3000 psi) up to the end of its rotation and maintain the pressure. Remove the hydraulic line from the unpressurised side.

A continuous fl ow of oil from the open hole in the casing indicates an internal leak in the piston. Refi t the hydraulic line in place and turn the shaft to the end of its rotation in the opposite direction. Repeat the procedure indicated above for the other hole. If there is an internal leak, dismantle the actuator, inspect it and repair it.

ADVICE

To avoid contaminating the wear parts:

Be careful to work in a clean environment.

If a test bench is available, you should use it to test the actuator. The separation pressure, the pressure at which the shaft starts to turn, should be approximately 28 bars (400 PSI). Operate the actuator at least 25 times at a pressure of 210 bars (3000 psi). After 25 rotations, increase the pressure to 315 bars (4500psi) to check whether there are any leaks or cracks. Repeat this test after rotating in the opposite direction.