Graco BetaCell 241D, Операция

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General Description
The Gusmer BetaCell 24:1 machine is manufactured to operate on 460V 3 . 60 Hz electrical
service with a current draw of approximately 100 amps.
The operation of the machine combined with processing of the chemicals require
precautionary measures described in the maintenance/operator's manual.
The principle of operation is that two Gusmer pumps, one for Curative, and the other for
Prepoly, deliver chemicals to a dispensing gun at the foam application station in a circulating
manner. Initiating the dispensing of the foam is under the operator's control. Deactivating a
safety by use of a double trigger pull allows the operator to commence a shot, which causes the
gun to open and foam to be dispensed. The quantity of foam
dispensed is controlled either by the operator’s release of the trigger or the control system’s
completion of the desired shot size.
Shot sizes and sequences are programmable by qualified technicians and are openly displayed to
the operator on his/her operator screen.
Temperature control of the chemicals is maintained by setting the individual digital
controls within the PLC. The new circulation system ensures constant and accurate temperature
control.
PID programming of the temperature controllers allows operation within a given
temperature range. Operation outside the designated range activates alarms and could
include simultaneous shutdown of the machine.
The machine has one FVD driven pump and one linear drive pump, each with their own flow
meter control loop. This ensures extremely accurate flow rates and therefore ratio control.
While in the non-dispensing mode, chemicals in the metering machine are constantly circulating
through the orifices in the head. This not only keeps the orifices clean, but also ensures constant
flow and temperature control. This feature of the
design also allows for elimination the requirement for high maintenance heated hoses.
Pressure transducers also feed information to the PLC. The software program within the
PLC allows operation of the machine within a given pressure range, the operation within
a wider pressure range will activate a high pressure alarm with potential simultaneous
shut down of the machine.
The Gusmer equipment includes Buffer tanks, which act as on board chemical reservoirs. These
tanks are temperature and pressure maintained and includes agitation to ensure product quality.
Material is fed into the Buffer tanks via the chemical feed system header.