Danuser 9000 Postmaster/SlabBlaster - Manual (Page 7)

Filtration Requirements:
• A filter of, at least, 25 micron filtration is required. A filter capable of 10 micron
filtration is preferred. The majority of paper type filters are 25 microns or better.
• A low pressure type filter can be installed in the return line from the control valves to
the sump. A low pressure type filter can, also, be installed in the sump or pump intake
line, but must be sized large enough to avoid starving the pump.
• A high pressure type filter can be used between the pump and the control valves.
• If the source of the hydraulic power does not have a filter, it will be necessary to install
one at some point in the system so, at least, part of the hydraulic oil is being filtered
whenever the system is operating. After a filter is installed and before attaching the
Postmaster/Slab Blaster, the entire hydraulic system should be drained, filled with new
oil, and operated for 30 minutes or until the system is warm. During this run time,
operate all valves, cylinders, and hydraulic motors on the attachment.
Pressure and Flow Requirements:
• The Postmaster/Slab Blaster is designed to operate at 12 GPM and 2000 PSI.
Valve Requirements:
• The hydraulic system used to power the Postmaster/Slab Blaster should be equipped
with a four-way valve large enough to carry full pump outlet without restricting flow
and causing oil heating.
• The four-way valve requires a relief valve which will open and relieve extreme
pressures between the Postmaster/Slab Blaster and control valve, even when the control
valve is in a neutral position. This feature can be obtained by connecting two external
relief valves between the main lines running from the control valve to the Postmaster/
Slab Blaster in such a way that high pressure in either line will be relieved to the other
line.
Hydraulic Fluid Selection Requirements:
• Premium grade petroleum based fluids will provide the best performance.
• Fluids that contain anti-wear agents, rust inhibitors, anti-foaming agents, and oxidation
inhibitors are recommended.
• The viscosity of the fluid should never fall below 70 SUS (13 cST). The best
viscosity range of the Postmaster/Slab Blaster is 100-200 SUS (20-43 cST).

NOTE
The life of the hydraulic motor is almost entirely dependent upon cleanliness
of the oil. Instructions in your vehicle operator’s manual regarding filter and
oil changes should be carefully followed. Even small amounts of dirt in the
hydraulic oil can cause premature motor failure that is not covered by warranty.
Hydraulic
Requirements