Becton Dickinson Diagnostic Systems now uses a specially designed 10-head meter, mix and dispensing system from Liquid Control Corp.

Becton Dickinson Diagnostic Systems (Franklin Lakes, NJ) manufactures the Bactec 9000 series of automated blood culture systems. These blood culture systems are used in hospital laboratories to help diagnose life-threatening diseases.

The Bactec 9000 has different microbiological media that are aseptically housed in glass bottles, and an instrument that incorporates advanced fluorescence detection technology.

The manufacturing process for the Bactec system requires a small amount of silicone to be dispensed into the bottles. When demand increased dramatically, Becton Dickinson needed a better way to dispense the silicone. The company now uses a specially designed 10-head meter, mix and dispensing system from Liquid Control Corp. (North Canton, OH).

Bottles approach the dispensing station on a conveyor. When they reach the dispensing station, a Z-motion device brings the dispense heads (each fitted with a special nozzle) to each of the bottle mouths. At that point, a precise amount of silicone is dispensed into the bottom of each bottle.

Application criteria included all stainless steel construction and onboard reservoirs with capacity to hold enough silicone to meet one-half of a shift requirement.

Silicone is gravity-fed from each reservoir to Liquid Control's Posiload Mini positive displacement piston-type pumps. Twenty of these pumps are located on 10 Posiratio Mini variable-ratio metering machines mounted in a stainless steel enclosure. This allows the system to comply with rigorous in-house cleanliness requirements. A digital shot selection system ensures repeatable deposits from one bottle to the next. A snuff-back device on the Twinmixer mixing heads ensures a positive no-drip cutoff, whereby the dispense heads can cleanly index to the next bottle. The Posimixer ensures that the silicone material is thoroughly mixed and allows for easy clean up and shutdown.

A special feature on the machines is that the pumps can be removed without having to empty the silicone out of the system, eliminating any extended downtime.

For more information about dispensers, call 330-494-1313 or visit