Graco BetaCell 241D, Операция

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Overview
The Gusmer PowerPack is a high performance hydraulic unit designed to
operate the gun at a sufficient pressure to prevent sticking and at a
sufficient speed to assure proper mixing.
The PowerPack incorporates a precision, high pressure, fixed output gear
pump in combination with an automatic pressure unloading valve and an
accumulator. The gear pump is the pump of choice because it is simple in
construction, reliable in operation and has proven to be the most cost-
effective way of generating hydraulic energy.
The function of the hydraulic pump is to charge the accumulator to
operating pressure, and the pump has been sized to do this in as short a time
as practical. It is the accumulator, not the pump, which is actually the
prime mover in the system and therefore a sufficient time for recharging
must be allowed between each discharge of the accumulator.
We
recommend 5 seconds minimum between shots. The minimum time
allowable is factory set to 3 seconds.
This service factor will also determine the amount of cooling required, if
any, to maintain the hydraulic fluid at temperatures below 150
°
F. The
more frequent the shots the more heat generated by the system
To protect against a failure due to high fluid temperature, a temperature
limit switch factory to 160
°
F is installed in the reservoir. This limit switch
will shut down the hydraulic motor and be accompanied by audible and
visual alarms.
The controlling component in the hydraulic system is the automatic
unloading valve. This dual acting valve has two separate settings: one to
define the upper operating pressure limit and the other to define the lower
operating pressure limit. When the accumulator is charged to the maximum
limit, the unloading valve diverts pump flow to the recirculation line back
to tank. During this recirculation, pressure is maintained in the
accumulator by a check valve in the unloading valve. When the
accumulator is below the upper limit, the unloading valve automatically
directs flow to recharge the accumulator.
The unloading valve is factory set to 2400 psi upper limit and 2200 psi
lower limit. It is recommended that these settings be maintained.