Fault finding on Electro-hydraulic and pneumatic systems 2

[koray1986]

First of all I would like to say hi to everyone and happy new year.

Please, could someone explain appropriate procedure that should be followed when fault finding on Electro-hydraulic or pneumatic systems?

Thanks.

 

[HPost]

I tend to follow these generic steps...

1) Find out how the system should work

2) Identify how the fault was found or how it developed

3) Identify what could be wrong

4) Narrow the list down to most likely failure modes. Understanding that strange things can and do happen.

5) Fix the fault

6) Re-commission the system with the understanding that anything can go wrong.

The reason I say this is that some faults develop over a long time, such as pump wear, where a motor or actuator slows down as result. People have been know to open up all of the flow control to gain some speed. Installing a brand new pump, can have some very interesting results when there is no flow control in the system. As a general rule always back the pressure controls off to zero and bring the system pressure back under your control. From experience, people don't like it when you launch their 2000 litre reservoir through the factory roof.

Experience is the best lesson and the application of care and planning will help keep things safe.

7) Don't take risks. Things can go very wrong...very quickly.

8) If you are not sure, ask for help.

This is of course a very basic process and should not be taken as read. Indeed there can only ever be generalised guides to such things. There are never a guarantees and it may well be the case that the system has been designed badly and has inherent faults.

I would go as far as to say that fault find procedures need to be demonstrated rather than read about. The hidden dangers within fluid power systems can do untold damage.

In summary, if you don't have sufficient knowledge and understanding of fluid system. Stay well away and ask for help.

Regards

HPost CEng MIMechE

 

[koray1986]

Thanks for your quick response and appreciate your help, thanks.