7.4 Instructions When Piping
7.4.1. Air Receiver
To prevent the pressure fluctuation and save the power
by utilization of capacity control feature, install the air
receiver tank whose capacity is not less than the value
shown in the following table to the discharge pipe.
Do not install a check valve between the compressor
and air receiver tank.
When the pressure drop between the air receiver tank
and compressor is increased, the load-unload operation
is repeated more frequently, leading to shorter replace-
ment interval of suction throttle valve and other parts.
Always install the separate air dr yer and line filter in
the downstream of the air receiver tank.
Model
Minimum Capacity of Air Receiver
OSP-55VAN
0.7 m
3
OSP-75VAN
1.24 m
3
7.4.2. Discharging Air pipe
(1) Discharging pipes must be joined with an Union or
a Flanged joint, and a Stop Valve must be fixed to
them for maintenance and inspection.
150 mm or more
When connecting dis-
charge air piping, con-
nect with the flange or
union joint at least 150
mm from the rear cover.
Drain Valve
Discharge Air
Stop Valve
Union joint or Flanged joint
CAUTION
(2) If there is concaved or upright piping in the run,
install a drain valve at the bottom of the run to pre-
vent the accumulation of the drain.
To connect the discharge pipe to your horizontal
plant airline, keep a space of more than 500 mm
between the horizontal plant airline and the
HISCREW
rear cover so that the rear cover can be
easily detached.
Drain Valve
7.4.3 Parallel operation
(1) At one-unit is in operation, completely close the stop
valve to the discharge pipe on the compressor
which is not operating.
(2) In case the unit is installed in parallel with a recipro-
cating compressor, be sure to install an air receiver
in-between to prevent the propagating vibration
from reciprocating compressor. Connect piping to
the air receiver’s outlet side as shown in the figure.
with taper between about
1/100 and 1/200 down to
the drain valve.
Stop Valve
Discharge Air
Drain Valve
Check Valve
Connect to the outlet
of the Air-Receiver
(3) In case of connecting the discharge pipe to a main
pipe, joint the discharge pipe from over to the main
pipe to prevent the condensate from back-flowing.
Discharge Main Pipe
From Compressor
Connect so that a direct load is not placed on
the discharge piping of the compressor.
CAUTION
35
7. INSTRUCTIONS FOR INSTALLATION [Instructions When Piping]