Bacharach 67-7622, Installation & Operation Instruction

Page: 15 / 96

Instructions 67-9319
Bacharach, Inc.
Page 1-9
INJECTOR CALIBRATOR CD3 INTRODUCTION
Calibration fluid is drawn from the reservoir (1)
through an externally mounted suction filter (2)
and is routed to the gear pump (3) .
Fluid is then routed to a final stage filter (5)
through a steel capillary tube (4) , which acts as a
damper to reduce the cyclic pressure variations of
the gear pump.
From the filter, the fluid is routed to a steel surge
chamber (6) , which reduces pressure fluctuations
due to the injector metering cycle. A precision back
pressure regulator (7) controls pressure of the
calibration fluid.
A spring-loaded injector fuel arm (8) admits fluid
into the inlet orifice of the Cummins cylindrical
injector. The arm contains a spring loaded shutoff
valve which opens as the fuel arm is lowered onto
the injector orifice by an over-center toggle clamp.
For the Cummins flanged and DD injectors the fuel
arm is bypassed.
When lever “B” on the operator’s table is in the
UNCLAMP position, fluid is directed into the rod
side of the cylinder to retract it for unclamping.
During cylinder retraction and when the piston
reaches the end of its travel, the relief valve (4)
dumps the fluid to the reservoir.
The same pressure is also used for the pilot to open
the check valve (6) which helps to accelerate the
piston retraction.
During retraction, fluid from the blind side of the
cylinder is displaced through the selector valve and
the pilot operated check valve to the reservoir.
When lever “B” on operator’s table is in “neutral”
(normal) position, all calibration fluid is routed to
the reservoir so it can be kept at a stable
temperature.
(b) Injector Supply Circuit (Rail Pressure)
(Fig. 1-12)
The injector supply and the clamping circuits share
the suction filter. All three circuits share a thermo-
statically controlled reservoir of calibration fluid.
Figure 1-11. Clamping Circuit