Contributed by Robert Sheaf, Founder of CFC Industrial Training
In this month’s troubleshooting challenge, we deal with a lifting a bent plate from a steel plate bending press machine. The accumulator safety unloading valve was damaged and the magnet on the plate lifting crane failed (see circuit attached). They repaired the crane magnet and replaced the damaged hydraulic valve. On start up, they bled the system of air and cycled the crane hydraulic system. When they shut off the power to the crane and hydraulic system, the spin-on return filter element blew off, spilling oil all over the floor.
The technician installed a new clean element, which promptly blew off again when the system power was shut off. Engineering decided to increase the flow rating of the filter head and element assembly. When the larger assembly was installed, excessive leakage occurred immediately between the head and the spin-on element when powering down the hydraulics.
They reviewed the PLC program and found it was sequencing correctly, as originally designed. They decided to remove the complete filter assembly. On this try, they blew the breathers off the top of the reservoir on shutdown.
What would you do next? Can you identify what was the problem? We welcome responses of all kinds directly to Robert Sheaf at rjsheaf@cfc-solar.com or to mgannon@wtwhmedia.com. The solution will be provided in conjunction with next edition of Fluid Power World and will be published online in March.
Filed Under: Components Oil Coolers, Featured, Filtration, Technologies, Trending
