Stanley MSD 1000, Руководство по безопасности, эксплуатации и техническому обслуживанию

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Operation Section 4 Page 7
MSD SABER SERIES SHEARS
SPEED VALVE OPERATING CHARACTERISTICS
The function of the speed valve is to increase the shear closing speed (cylinder extend function) when the
shear is not under a load, thereby reducing cycle times and increasing effi ciency. The speed valve directs
return fl ow from the rod side of the cylinder to the bore side as the cylinder extends. This function occurs
only when the cylinder is extending in a “low to medium load” condition, which occurs as the upper shear
jaw is moving toward the material to be cut. As the shear jaws close down on the material to be cut, the
cylinder meets resistance and requires more operating pressure. The pilot valve on the speed valve senses
this increased pressure and shifts the valve spool out of the speed mode. The rod side fl uid is now directed
back to the base machine reservoir and full system operating pressure can now be directed to the bore side
of the cylinder, allowing the shear to cut the material with maximum force.
GETTING THE FEEL OF THE SHEAR
Before starting the fi rst job with a new machine, it is suggested that the operator fi nd an open spot on fi rm,
level ground that’s free of obstructions such as trees, buildings, people, and other equipment. Move the
machine to this area, and spend some time just getting to know the “operating feel” of the machine and the
shear. The machine is extremely powerful. Be concerned about safety when preparing to operate the new
machine. Ensure safe operation by inspecting the machine as stated in
Getting Started Safely . Read the
Getting Started Safely section of this manual and understand it.
The control levers should be moved in a gradual, deliberate way rather than with jerky, abrupt movements.
Jerky operation can cause damage and early wear to various parts on the machine, and can also overheat
the hydraulic system. For example, as each control lever is moved forward or backward from the center,
or neutral position, the oil fl ows to the cylinder or motor controlling a function. The component (boom,
attachment, etc.) starts to move. The component moves faster as the control lever is moved further forward
or backward. Holding the lever in the forward or backward position will hold that movement at a given rate
of speed. To slow the movement down, gradually move the lever toward the neutral position. Movement is
stopped at the neutral position. The position is maintained until the control lever is moved again. Feathering
the controls is a technique that will increase output and make operating the shear easier. When starting any
motion of the machine, move the control slightly from neutral until it starts to move, then smoothly move
the control to increase motion to desired speed. Do the same when stopping a motion.
•
The amount of rotation your shear will achieve per fl uid charge depends on the shear model.
•
Continuous rotation can be achieved by cracking an excavator function that charges the accumulator.
•
The accumulator needs to be charged with fl uid when the base machine is fi rst started up. The unloading
valve is designed to drain to the accumulator whenever the base machine is shut off.
NOTICE