1. Routine Maintenance for Hydraulic
Press
a. It is important that users keep the hydraulic press and
the working environment clean.
b. Change oil strictly following the
recommended oil drain interval.
c. Regularly check the oil and the joints
to ensure there is no leakage.
d. Make sure the foundation is in good
condition and no vibration is produced.
The above-mentioned points are the
outcome of experience, so users are recommended to try to act accordingly.
2. Operating Speed of Hydraulic Press
When the hydraulic press is feeding with heavy load, the working pressure is
high. In order to ensure no overloading of hydraulic pump, it is necessary to
reduce the flow, or the working speed of the hydraulic machine.
The
working pressure is low when the machine returns with lighter load. In this
case, the flow or the operating rate of the hydraulic press can be increased, as
long as it is not beyond the output power capacity of the hydraulic pump.
In a word, the operating speed of hydraulic press is only related to the flow.
When there is large flow, the running speed is high; and the speed is low when
there is small flow.
3. Operating Instructions for Hydraulic Shearing
Machine
a. Wear tight protective clothing, with the cuffs and
lower hem tightly fastened. Never change clothes near the machine when it is
working. Do not wear apron or cloth of its kind to avoid being caught up in the
machine. What's more, operators must wear safety helmets and put their hair
inside the hats. No skirts or slippers are allowed.
b. The operators must
be familiar with the main structure and performance of the shearing machine, and
know how to use it correctly.
c. The machine can only be used to shear
steel plates, copper sheets, aluminum panels, and non-metal sheet materials of
thickness ratings and without hard scratch, welding slag, slag inclusion, and
welding seam.
4. Hydraulic System of Hydraulic Press
The hydraulic press uses fluid drive which has become the main type of driving
for pressing machinery. The press is applied to a variety of forging and
pressing as well as press molding work of steel, metal structures, plastic and
rubber products, etc. The hydraulic machine is key equipment in the heavy
machinery manufacturing, aviation, plastic and non-ferrous metal processing, and
other industries.
The hydraulic transmission system works on the basis of the change of
pressure energy, with high pressure, large flow and high power. Therefore,
special attention should be paid to improving the power utilization of the prime
motor, and to the impact and vibration prevention during pressure relief so as
to guarantee safety and reliability.
In the pressing process, the master cylinder of the hydraulic machine is able
to accomplish the basic working cycle of fast feeding- decelerating and
pressing- pressure maintaining - pressure release and return; and the pressure,
velocity and pressure-maintaining time are adjustable. The knock-out cylinder,
used to knock the workpiece out, performs the functions of knock-out, withdrawal
and stop. In case of thin sheet drawing, the knock-out cylinder is also needed
to be capable of rising, stop and pressurized return. Sometimes a blank holder
cylinder is utilized to compress the blank to avoid wrinkling. The maximum
output pressure (tonnage) of the main actuator (master cylinder) is referred to
as the principle specification of the hydraulic machinery which has been
serialized. The tonnage of the knock-out cylinder is commonly 20%-50% that of
the master cylinder. And the ejector cylinder tonnage of an extruding press can
be l0% of the main cylinder. Generally the blank holder cylinder of a double
action hydraulic drawing press provides 60% the tonnage of the stretching
cylinder. The speed of master cylinder is varied with the press working
requirements; for a hydraulic system with pump supplying oil, the speed of the
working stroke normally should not exceed 50mm/s, the fast forward and fast
backward speeds are the same which should not be more than 300mm/s.