How to “warm up” your excavator ?
How to “warm up” your excavator ?
In the whole digging machine problem, there
is a kind of fault that can make the old and new drivers equally helpless and
helpless. That is, the excavator is normal when the cold car or just started
work, but after a period of work, the excavator does not work and the speed
gradually slows down. So what is the cause of the failure, and how to
troubleshoot it?
1. Hydraulic oil replacement and
maintenance
Special reminder, relative to the car of
the age, the car with the breaker for a long time must change the hydraulic oil
on time, many of the faults are caused by the hydraulic oil, of course, the
hydraulic oil is thicker when the car is cold, so the pressure when the car is
cold Basically, the flow rate can be guaranteed. Once the temperature of the
hydraulic oil rises to about 60 degrees, the operation starts slowly. First,
look at the cleanliness of the hydraulic oil. The oil return filter and the
cleanliness of the oil filter are checked and judged.
Brick home reminder: the hydraulic oil
commonly used in excavators is No. 46. The bigger the grade, the greater the
viscosity. The lower the grade, the high temperature is very easy to occur. The
higher the viscosity of the grade will affect the speed! Komatsu excavators now
also recommend Komatsu TO10 special transmission oil.
2, control the oil circuit failure
When the hot car is slow, check the pilot
pressure first. If the pressure is too low (minimum 3.2MPA), then check if the
gear pump (Komatsu self-pressure reducing valve) is leaking. Is the pilot
filter (filter) miscellaneous? Causing blockages. If the pilot pressure is not
enough, the main control valve working device stem cannot be fully opened,
resulting in slow speed and no force.
3, the main pump failure
The hot-vehicle slow-fault main pump is
also one of the reasons. When checking the pressure flow of the main pump, the
reaction after adjustment is not large or basically no effect, then the main
pump should be removed, the regulator wears, the servo plunger wears, and the
distribution plate Wear, the plunger and cylinder wear, the swashplate wear,
and the wear and tear in these places will cause the hot car pressure flow to
be low.
4, electromagnetic proportional pressure
reducing valve failure
There is also a component that affects the
main pump pressure and flow rate is an electromagnetic proportional pressure
reducing valve (each brand is called different, the function is basically the
same), the electromagnetic proportional pressure reducing valve function is to
obtain the signal current provided by CPU computer version, so that the pilot
pressure is carried out. The proportional pressure is reduced to control the
output oil of the pump. If there is a problem, the flow pressure of the pump
will also be too low or the card will not adjust at a certain position.
5, the main control valve failure
The main control valve internal leakage is
the main reason for the slow speed of the hot car. The main reason is that the
daily maintenance is not in place. The hydraulic oil is not checked or replaced
in time. The frequent use of the crusher is also the main cause of the main
control valve. The pressure of the crusher is improperly adjusted, and the
hydraulic pressure is not replaced in time. The oil will cause impact wear on
the valve stem of the main control valve, the main relief valve, and the oil
port relief valve, and finally cause the internal leakage to be slow.
The above points are the main reason for
the slow speed of the excavator after the hot car. Whether it is the
maintenance master or the excavator boss, we must first find the root cause of
the fault and then “prescribe the right medicine”.
