Accutek pinch series fillers
Accutek pinch series are economical and easily cleaned fillers that deliver consistent fill levels over time. The product delivery pump selected needs to provide constant pressure and the time that product flows into the containers must be regulated to maintain consistent fill levels.
Selecting a pump compatible with the intended product and filling technique is required. The pump technologies that Accutek recommends for the pinch series fillers are as follows:
• Positive displacement
• Pressure pot
Positive Displacement Pumps
Gear pumps fall in the broad category of positive displacement pumps. This type of pump can generate good pressure levels with clean moderately viscous liquids because of the tight mesh of the internal gears. Gear pumps require a bypass path to bleed off pressure when the product delivery tubes are pinched closed. Gear pumps need to be primed and should not be run dry for any length of time.
Centrifugal pumps that have stainless steel impellers and housings are easier to sanitize. They can tolerate particulates in the product. A centrifugal pump will not overpressure the product delivery tubes when they are pinched close. These types of pumps tend to be self-priming and may be run dry for brief periods of time. This pump type is not recommended for foamy products.
Use one of the above pump types to keep a surge tank mounted above the fill heads full of product. Gravity fed product is not agitated and flows smoothly into a container.
Product is placed in a two or five gallon pressure pot. The pressure pot is sealed and an air hose is connected to the pot. The air pressure pushes the product through the filler and out the nozzles. This technique is also gentle with the product.
Product is routed through a manifold that has an output port for each product delivery nozzle. There is a product delivery tube connecting each manifold port to a nozzle. The product delivery tubes run between a pinch bar and pinch plate that can close the tubes on command. Pinch series fillers have a smooth product flow path that makes it much easier to clean than conventional valve systems.
There is a flow rate adjuster in line with each nozzle to equalize the flow rate between nozzles. With the flow rate for each nozzle set the fill dose will be equal and determined by the time that the pinch bar is open. Pinch bar timing is microprocessor controlled to the nearest one hundredth of a second.
Laboratory testing with a number of different types of nozzles is needed to find the type and size nozzle that works best with a particular product. Each product requires a different nozzle configuration. For instance, a bubble forms at the tip of a nozzle when the nozzle diameter is matched to the surface tension of the product. This bubble prevents dripping at the end of a fill. In other cases a screen can be mounted inside a nozzle to prevent foaming.
Product contact parts must be evaluated for chemical compatibility. Contact parts include product tubing, the manifold, and the pump. The fill temperatures and product abrasiveness will determine the elastomer type needed. Some common types of elastomers used are:
• Encapsulated Silicon
Automatic fillers can be configured to fill up to twelve containers at the same time. The user friendly touch screen controls on the automatic models enable additional filling approaches. Most applications move a set of empty containers into position to be filled at the same time. Some product types are best filled a step at a time.
The diagram to the right illustrates step filling. The flow controls and fill time are set so that a container receives a partial dose at each fill station. The container is not full until it exits the last fill station. This technique is often used for foamy products.
An all pneumatic upgrade is available for filling flammable products. The all-pneumatic upgrade includes pneumatic container sensors, pneumatic logic for timer and indexer operation, and container counting.
Products compatible with pinch series fillers.
Nail Polish Remover
Sun Tan Lotion
Hand & Body Lotion
Douche & Enemas