Although talk around the office water cooler may touch on topics as varied as last night’s playoff game or what CEO was indicted the week before, chances are the talk doesn’t often turn to the water cooler itself. But for those inquisitive enough to wonder how that water gets to the office, part of the answer is Aquatyzer Engineering. This Signal Hill, Calif.-based company manufacturers equipment that simplifies bottling companies’ operations, including machines that wash, fill, and cap 5-gal returnable polycarbonate drinking water bottles.
An operator starts the self-contained, fully automatic machine, and waits for bottles to be fed into the load area from a feed conveyor. The washer/filler/capper detects bottles in position and loads them into a special holding mechanism. The bottles travel through wash, rinse, sanitizing, and final rinse stages and are discharged onto a filler conveyor — still within the clean room environment of the system.
The all-sanitary filler system is totally enclosed, and the bottles are firmly held in position under the fill heads. Bottles then travel into the capping area, where caps are applied. Lastly, they exit the system and onto a discharge conveyor. Impressively, bottles do not leave the clean room environment until they are capped.
Pneumatics and control
A standard washer/filler/capper processing 900 of the 5-gal bottles per hour will require compressed air at a rate of 12 cfm at 90 psi. The pneumatics are controlled and operated by a Siemens S7300 PLC, which positions valves within a Festo CPV module, to route pneumatic pressure to desired parts within the system. The system incorporates ProfiBUS DP, and uses various pneumatic actuators with bore sizes ranging from 32mm up to 63 mm.
“The integration of Siemens control and Festo ProfiBUS and Fieldbus components was a real factor in choosing this type of control architecture,” according to Al Delgado, head engineer at Aquatyzer.
“Troubleshooting is very intuitive with the common component approach,” he adds. Aquatyzer systems incorporate Festo CPV valves wherever possible to allow for standardized component selection and ease of assembly, use and field troubleshooting.
The washer/filler/capper is capable of handling multiple height bottles (3 or 5 gal). This posed a problem at the load and unload sections of the machine. Due to space constraints, one cylinder had to be capable of accommodating both sizes. Aquatyzer solved this problem by incorporating a Festo DNC cylinder with a 63mm bore, 280mm stroke and integral clamping unit.
The clamping unit is activated via sensors mounted on the cylinder’s body. When the machine is in 3-gal mode, it looks for the 3-gal sensor and ignores the 5-gal sensor — and vice versa. Once the appropriate sensor is activated, the PLC energizes a valve on the CPV manifold, which in turn stops the cylinder and activates the clamping unit. This provides the precise stopping control that is required to load each type of bottle.
The stop positions of the loading mechanism can be easily adjusted by moving the location of the sensor on the DNC cylinder groove. Flow control valves are used on the cylinder ports to control the speed in each direction. The load and unload mechanisms operate once every 15 sec, with a stroke time of 1.5 sec. Over a span of a year, this amounts to 500,000 cycles for a machine that operates 8 hours per day, 5 days a week.