Instruction manual

QR-25 Series Quincy Compressor
52201-107, December 2012 5 3501 Wismann Lane, Quincy IL - 62305-3116
Principles of Lubrication Systems
Moving parts within the crankcase are supplied with lubrication by a posi-
tive displacement, gerotor type oil pump. Oil is drawn up from the bottom of
the crankcase to the oil pump through an oil sump strainer screen. The oil is
then forced under pressure through the oil filter (if so equipped). Oil travels
under pressure through drilled journals in the crankshaft and connecting rods
to lubricate crankshaft bear ings, connecting rod journals, wrist pin bearings
and the cylinder walls.
Principles of Cooling Systems
Fan blades of the compressor sheave force ambient air across fins of the cylinder
head(s), and intercooler fins of two stage compressors, to cool the compressor.
QR-25 series compressors are normally set up at the factory with a sheave that
turns in a counterclockwise rotation. For special applications, clockwise rota-
tion compressor sheaves are available as optional equipment on some models.
QR-25 series compressors should be operated in temperatures under 104°F.
Principles of Dryers & Filters
Moisture occurs naturally in air lines as a result of compression. Moisture
vapor in ambient air is concentrated when pressurized and condenses when
cooled in downstream air piping. Compressed air dryers reduce the moisture
vapor concentration and prevent water formation in compressed air lines.
Dryers are a recommended companion to filters, aftercoolers, and automatic
drains for improving the productivity of compressed air systems.
Water and moisture vapor removal increases the efficiency of air operated
equipment, reduces contamination and rusting, increases the service life of
pneumatic equipment and tools, prevents air line freeze-ups, and reduces
product rejects.
Control Components
Unloader Towers: Provided as part of the basic compressor when control
version is specified.
Pilot Valve: Used in conjunction with unloader towers when the compressor
is to run continuously and an operating pressure range is to be maintained.
Refer to your parts manual for correct pilot valve, ranges and settings.
Hydraulic Unloader: Used on pressure lubricated compressors to protect
the compressor in the event of a potentially damaging oil pressure drop. Also
ensures that the compressor does not begin to produce compressed air until
there is sufficient oil pressure.
Pressure Switch: Used for start/stop appli cations (usually accompanied by a
hy draulic unloader). The pressure switch detects the demand for compressed
air and allows the unit to start. When the de mand is satisfied, the unit stops.
Control Versions
Various control versions are available for the model QR-25 series compressors.
The control version required is determined by how frequent there is a demand