The virtues of viscosity

Overseas manufacturers of edible oils represent one of the fastest growing and most profitable sectors in the liquid filling business. Of the three key filling options available - weight, volume and level - weight is often selected for such products, especially when sold in bulk.

It is particularly advantageous in climates with hot days and cold nights when temperatures will affect viscosity of liquids and performance of machinery, thus making it more difficult to achieve fill consistency if filled by level or volume.

Volume solutions are achieved through piston or flowmeter filling. Users choosing flowmeter filling have two further options to consider - mass and electromagnetic.

Mass, the more expensive of the two options, is intended to handle oil-based products such as lube oil, which doesn't have an electromagnetic field. Understandably, the electromagnetic version is able to handle fluids with an electromagnetic field, typically water-based products such as shampoo and drinks.

The level approach is typically used for filling into glass where customers will buy on fill appearance, as in perfumes and spirits. Fill methods can include gravity, vacuum or pressure.

Of course there are many other parameters to be considered, but perhaps the most important include the required fill speed, the space available and the container shape.

"At GEI Gravfil we are experiencing strong demand for our products from overseas manufacturers of edible oils," says general manager Roger May. "Designed for this very purpose is Gravfil's six-head Excel liquid filler. Showcased at Total, this system has proved popular with contract packers and the export market. The Excel offers accuracy, consistency and flexibility."

Momin Oil in Dubai, a leading food oil manufacturer, is currently awaiting delivery of a seventh Excel in order to further increase output in response to consumer demand. In this latest instance two sets of nozzles were supplied to ensure that Momin achieved the required performance levels over both a wide range of containers and variety of hot and cold fill oils.

Designed to operate without the need for change parts, the six-head in-line Excel incorporates multi dosing to deliver a filling range capacity ranging from 500ml to 20 litres and operates at levels of up to 10 tons/hr. Standard features include the option of PLC or pneumatic controls, automatic flushing, diving nozzles, vacuum drip removal, 'no bottle no fill' and fill accuracy to within 0.15%.

"With processors and packers under increasing pressure to trim margins, yet maintain quality and flexibility, they look to manufacturers to come up with innovative new ways of de-skilling operations," added May.

Rapak, part of DS Smith Plastics, also has a strong interest in the edible oil market, having recently installed an Autokap single head fully automatic filler at Anglia Oils in Hull. Anglia is a major supplier of edible oil to Burger King and is now using Rapak's bag-in-box system to pack the oil for use in most of the Burger King outlets in Europe.

The bag-in-box system offers many benefits over existing packaging but one of the principal reasons for the change was environmental legislation in Germany. The bag-in-box is lighter and easier to dispose of, while the bag, cap and gland are all 100% recyclable, offering both environmental and commercial benefits.

"The move towards bag-in-box for edible oils represents a step-change in improving costs and efficiency in a key aspect of fast food retailing," comments sales and marketing director Jon Wragg. "We expect the trend to continue as this method of packaging helps manufacturers and retailers maintain their competitive advantage."

Rapak's range of fillers allows end users considering this technology a simple and swift transition from existing packaging to a new packaging format. Autokap, along with the optional Ultra Clean fill head configuration, for example, provides multi-purpose clean filling for a variety of products, including chemicals, wine, milk, edible oil, fruit fillings and post-mix syrup.

This liquid filler features high levels of automation and touch screen controls. Servo drive systems allow fast, multi-position strokes and repeatable feeds with acceleration and deceleration set to bag size, plus automatic bag size and cap height changes.

New bag-in-box sectors opening up

Rapak bag-in-box filling systems are available for most liquid operations for pack sizes from 2 litres to 1000-litre IBCs, including 220-litre drum liners. A modular design with common electrical controls, pneumatics and bag into box loading systems, ensures ease of maintenance and upgrading of equipment. "While this is ideal for manufacturers in traditional bag-in-box markets such as wine and post-mix syrups, it is also opening up new opportunities in other sectors," says Wragg.

Avery Weigh-Tronix has experience of dealing with syrup of varying viscosities, recently installing a weigh filling system to increase production throughput and efficiency at the liquid syrup filling operation of Tate & Lyle European Cane Sugar at its Thames refinery in London.

Products are sold in 7.2kg pails, 25kg pails, drums and 1250kg IBCs to food and pharmaceutical customers. The Avery Weigh-Tronix system is in operation on the liquid filling area where it fills products of widely varying viscosity from liquid sugar to treacle. All the products are filled at a temperature of 55O deg C.

When Tate & Lyle relocated the container filling operation from its former site at Millwall to the Thames refinery, the company wanted to update the existing system. This comprised five weigh-filling stations, some mechanical, but each dedicated to filling a different container size.

The objective was to instal the latest electronic filling system and therefore increase efficiency and throughput. The equipment also had to fit within a new building at the Thames refinery, which had greater headroom but less overall floor space.

Two Avery Weigh-Tronix scales now control the entire weigh filling operation. Under the new system, the filling stations fill 25kg drums and pails, 210 litre drums and 1250kg pallecons. The 7.26kg pails are filled using a portable scale, which can be plugged into one of the weigh control units.

The design of the new system means several 25kg pails can now be weighed together on a pallet rather than filled individually and manually lifted onto the pallet. As a result one operator can control the filling process rather than two, increasing efficiency and safety.

The compact weigh filling stations occupy a smaller floor area in a building with greater headroom, which has enabled Tate & Lyle European Cane Sugar to increase pressure to the filling operation and further improve efficiency. The new system also offers greater flexibility as two containers now fill all container and IBC sizes rather than having one dedicated scale for each container.

Programmable filling valve

Another development in weigh filling, the Libra, was launched at Total by Ocme UK and features a programmable filling valve. This permits a variety of products to be filled into various container shapes and sizes to be handled without long set up times as the filling valve is set automatically to suit the application.

The patented filling valve mechanism is designed to be outside the product tank. This is said to make the tank and filling valve ultra clean, allowing the most sensitive products to be handled. Libra fillers/cappers are available in several frame sizes with 8-64 filling heads. They offer speeds of up to 600 containers/min in free standing or monobloc format. Containers can range in size from 50ml-5-litre capacity.

Ocme's container handling parts are colour coded with 'no tool' quick release, which is said to enable the machine to be changed over in minutes.

Fast and frequent changeover was something that PKB took into consideration with the development of its Robo semi-automatic filling, screw-capping, crimping and press-fitting machine. The French manufacturer, which specialises in filling and capping machines for another lucrative sector - cosmetics, toiletries and fragrances - says that the line is particularly suitable for contract packers or for perfume and cosmetic firms that face frequent product changeover.

The Masterfil range also includes single head semi-automatic machines and fully automatic flowmeter-based systems for applications that extend from personal care products through to paint. The company's Multifil range of automatic filling and capping machines handles containers from 5ml to 10 litres at three variable fill speeds, while nozzle rise patterns are adjustable to allow filling at the optimum speed, depending on container shape and product consistency.