Hydraulic cylinder troubleshooting,hydraulic cylinder trouble shoot

Hydraulic cylinder troubleshooting

The processes for hydraulic cylinder troubleshooting can be as following steps:
(1).Find out the properties of the breakdowns, like speed doesn't meet the requirement, import pressure isn't suitable, no movement, no stable movement ,wrong moving direction, wrong moving order, crewing etc. No matter which kind of the error it always can be some basic problems like rate of flow、pressure、direction、position、force etc.
(2)List an elements catalog that might cause the breakdown, for example: too slow of rod speed, it can be because of now enough flow, then list an elements catalog that might influence the flow, and then analysis whether it'sbecause the flow valve is blocked, or because of the barrel leaking, or because the pressure-control valve leak too much etc. then repair or replace the broken element .
(3).Check the hydraulic cylinder'sown problems If there is nothing wrong with all elements and the parameters of each passage is normal.

Now let's analysis some typical working breakdowns - hydraulic cylinder troubleshooting:

1.Bad movement of hydraulic cylinder
Hydraulic cylinder'sbad movements can be: can't move of hydraulic cylinder; insensitive movement of hydraulic cylinder, crawl movement of hydraulic cylinder etc.

2.No movement of hydraulic cylinder
No movement always happen on the hydraulic cylinders that are just installed. Firstly, check the reason from the outside of hydraulic cylinder; check whether the resistance of organs that dragged by hydraulic cylinder is too big, whether there are problems like blocking、keying in 、holding other components ;Check whether the hydraulic pressure reaches the rated value, if it doesn't then check whether it is because the system is leaking too much or pressure regulating of spill valve is not working etc. If everything is ok with the outside of hydraulic cylinder. Then check the inside reasons of hydraulic cylinder, and take some relevant measures. The ways to check the reason for no movement of hydraulic cylinder are as following methods:
①Check the leaking problems of each oil-way system to rule out leaking.
②Check whether the seal ring between piston and piston rod is damaged 、ageing、loosening etc.
③Check the reason why the pressure can't be increased is because there is something wrong with the hydraulic pump or pressure valve.

3.The oil hasn't flowed into hydraulic cylinder
Method:
①Check whether the oil pipe、oil-way especially the pipe joint is blocked. Check all the way from barrel to oil-way to rule out the reason is blocking
②Check whether There is dirt in spilling valve so the sealing between is not good enough and result to make the oil flow back to the oil box.
③Check whether the spring of electromagnetic valve is broken、whether the electromagnet coil is burnout, and whether the changing of oil-ways isn't working

4.the sealing friction is too big because the components matching is too tight
Ways to rule out the troubles
①Matching between piston and piston rod isH8/F8
②The depth and width is strictly accordance with dimensions tolerance
③Adjust seal friction to moderate level when using V type seal ring.

5. Inappropriateness of designing and manufacture
When piston rod is in return trip after move to the end, hydraulic pressure can't effect on the effective working area, or the effective working area is too small. If this happened, then the designing and manufacture should be improved.

6. transverse load is too big, force holding, scuff seizure
Troubleshooting
① Make the axis of the cylinder with movement direction when install hydraulic cylinder
②make the load of hydraulic cylinder pass through the axis the cylinder so not have eccentricity;
③when put a long hydraulic cylinder in horizontal way, piston and rod will have deflection which will make guide bush and piston to have unbalance loading,making the cylinder gland seal broken、oil leaking、piston blocked inside of barrel.what we can do is:
a. making the piston bigger
b. making the shape of piston exterior circle to be waist drum so the piston can make itself located to improve force situation and reduce scuff.
c. The connection between piston and piston rod can use ball joint.

7. Reduce the counter pressure of hydraulic cylinder when it is too big.
One of the reasons why hydraulic cylinder can't work is because the hydraulic pressure of filler opening is too low to reach the rated value which means no enough working pressure, this usually related to the whole system..and the reasons why the working pressure is not enough can be:
①.breakdown of hydraulic pump
②reversal of hydraulic pump drive electrical machine or not enough rotate speed and power
③breakdown of pressure valve.
④others.:
a. oil filter is blocked、hydraulic passage is too small and oil viscosity is too high so that the oil can't be sucked up.
b. wrong pipeline
c. excess air in the oil and too much pollution
d. the viscosity of oil is too low to keep the oil inside
e. pressure gage is broken

hydraulic cylinder troubleshooting