SHURflo HeavyDuty Advantage BIB 94-360-05 Manual page 3

BIB Gas Pump Features and Operation
Straight Through Syrup Path- the Path of Least Resistance. The idea behind the SHURflo pump is to
move the gas rather than the syrup. This feature has been built in the design of the pump, which
provides a straight flow path for the product across the pump. This means the syrup has the least
amount of restrictions possible. The fewer the restrictions there are means less pressure drop within
the pump and greater CO2 savings. But more important the less pressure drop across the pump the
more consistent the quality of the drink.
Twin chamber double diaphragm positive displacement with designed Hydraulic Advantage- that is
given an inlet gas pressure the resulting force driving the syrup out is greater than the force applied
by the gas. This is because the piston surface area to the "gas in" side of the chamber is greater than
the effective piston surface area to the "syrup out" side. This difference gives the SHURflo pump a
hydraulic boost.
Gas (CO2/Nitrogen/Air) Driven- The pump can be operated by either regulated CO2, nitrogen or clean
compressed air. The compressed gas drives the pump and does not come in contact with the syrup.
The minimum gas pressure is 20 psi (1.4 bar) and the maximum is 85 psi (5.8 bar). The figures below
illustrate the flow of gas and flow of syrup when the pump is in operation.
Figure A Figure B
Figure A - The CO2 enters the control cover through the poppet valve (which is open on this stroke)
into the left CO2 chamber. The CO2 in the left chamber pushes the piston to the right, thus forcing out
the syrup in the left liquid chamber (syrup under pressure), while suctioning syrup into the pump to
the right chamber (syrup under vacuum). When the piston is fully extended, the switching system
activates, closing the poppet valve and diverting the CO2 to the right chamber.
Figure B - The CO2 enters the control cover through the poppet valve. The valve blocks the passage
into the left chamber, causing the CO2 to be diverted around the outside of the pump to the right
chamber. The CO2 in the right chamber pushes the piston to the left, thus forcing out the syrup on the
right side of the chamber (syrup under pressure), while pulling syrup into the pump to the left
chamber (syrup under vacuum). When the piston is fully extended, the switching system activates,
allowing CO2 to enter the left chamber, where the process in Figure A begins.