oleodynamic distributor

[sandro1274]

good day to all, my name is alessandro I am a mechanical designer
of 40 years. in the company where I work for a month we have serious problems with
an oleodynamic distributor, that is: the press that once taken to position from the electric motor does not immediately descend to cold oil, but pass ache a couple of seconds before it begins its descent to press the fuselage.
some distributors operate well the press both hot oil and cold others do not!.
the distributor is cast iron but in the samples we used steel and aluminum alloys, but the problem persists, despite the holes we make them do by numerical control machines.
the design-project of the distributor has remained unchanged in the last 20 years, but, only lately it has begun to give problems.
we came to the conclusion that it could be the fault of the valves made in cina, because this sudden loss of load we have no idea where it could come from since as I said the distributor always worked. Could you give me8 advice on this?
thanks in advance.

 

[MBT]

buy "series" valves and mount them on existing distributors
If the problem disappears, then you must immediately and urgently teach the office to purchase the two basic rules of the good buyer!

 

[meccanicamg]

you could connect the whole electrically both electrovalve and disconnected and check that the pressure drop is not the desired one. It is necessary to understand whether it is a switching delay of the valve or a small channel that takes time to give the flow.
If you can disassemble the valve and see if the travases are smaller.

 

[sandro1274]

actually today the valves have been changed one on all the maximum one!
and look a little surprised everything works and also well. thanks guys for answers and interest