Hydraulic Valve Solenoid Fails Frequently
Hydraulic Valve Solenoid Fails Frequently
(OP)
We have two identical hydraulic systems on a production line. One hydraulic valve coil fails daily (or even more often). The systems are the same electrically. My question is can excessive stiction in the valve or unusual forces in the mechanical system create this problem?





RE: Hydraulic Valve Solenoid Fails Frequently
RE: Hydraulic Valve Solenoid Fails Frequently
Not if the solenoid is built for 100% time with current on, and receives correct voltage.
The solenoids should be marked or type identification give information about feeding current limitations (nominal voltage plus/minus and time allowed with current on)
If the solenoids for the two valves are identical, and the performance required relatively identical, you should have a look at the factual input to the solenoid and check out necessary protection on the feeding line and source to ensure correct voltage without peaks when solenoid current is cut in and off and during use.
My guess is that the electrical systems differ in feed current or current peaks to the solenoid.
RE: Hydraulic Valve Solenoid Fails Frequently
If experiencing coil failure, consider replacing the solenoid coil with Class H, the high temperature insulation model. Solenoid coils usually comply with various standards and different temperature categories exist. Class F is a common rating with a temperature limit of 155 degree C. Class H increases the rating to 180 degree C.
If the problem relates to the frequency of cycling and valve stiction issues, consider using a solenoid valve as a pilot, operating a pneumatic supply to a pneumatically operated valve. This would not be a simple replace in kind situation and requires more work. However, I cannot imagine dealing with daily solenoid valve failure.
RE: Hydraulic Valve Solenoid Fails Frequently
You likely have one of a couple problems.
The valves are rated for operation at a certain maximum fluid temperature. If you exceed this temperature the coil's operating temperature exceeds its limits and melts.
You should check things out because this may indicate that your hydraulic system is running far to hot and the next thing to fail will be seals, pumps, rams, and the hydraulic fluid itself. Just fixing the valve/solenoid may allow worst damage to soon follow because the system now sheds half its load automatically on valve burnout.
Or, If the hydraulic fluid is not excessively hot and this is an AC solenoid any obstruction that prevent the valve armature from fully seating will cause the coil to burn out in less than two seconds. This is because AC solenoids draw 5 to 20 times their maximum current until they actually seat. If the valve is mechanically damaged or there is some debris somehow caught behind/above the armature, (like spring fragments), this would cause a random burnout.
If the coils only burnout after the system has run for an hour or more it is probably a heat issue and most likely your fluid overheating. Get a radiator put in asap. If the solenoid seems to fail entirely randomly, like five minutes after start up then it's probably a damaged valve.
Keith Cress
kcress - http://www.flaminsystems.com
RE: Hydraulic Valve Solenoid Fails Frequently
RE: Hydraulic Valve Solenoid Fails Frequently
BTW, it looks like ItSmoked answered your original question -- yes, if there is mechanical damage to the valve, it will affect the hydraulic system. If it's failing daily, then it's time to isolate the line and open the valve up.
Patricia Lougheed
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RE: Hydraulic Valve Solenoid Fails Frequently
Location, Location, Location. It's a pertinent here as in marketing.
Mike McCann
MMC Engineering
RE: Hydraulic Valve Solenoid Fails Frequently
Then I scratch my head, as why would anyone want to use a DC one in that location?
Keith Cress
kcress - http://www.flaminsystems.com
RE: Hydraulic Valve Solenoid Fails Frequently
RE: Hydraulic Valve Solenoid Fails Frequently
RE: Hydraulic Valve Solenoid Fails Frequently
Maytag