Ishida provides multi-head weigher to automate Tulip sausage packaging line

Steff Houlberg, now a part of Tulip Food Company, has partnered with Ishida Europe to automate the packaging of its long sausages in plastic pouches.

Steff Houlberg, now a part of Tulip Food Company, has partnered with Ishida Europe to automate the packaging of its long sausages in plastic pouches.

The new approach is said to deliver a neater, more consumer-friendly pack, but also saves considerably on plastic film,manpower and giveaway compared with the previous manual/flow-wrapmethod.

Long sausages pose many challenges to packing automation andhave traditionally been packed by hand. At the Steff Houlberg plant inRingsted, Tulip decided to upgrade from a combination of manual packing and flow-wrapping to an Ishida multihead weigher over a verticalbagmaker.

The company installed a new line in which strings of product are fed into a cutting machine which separates them into individual sausages.From here, a flighted elevator takes them to the top of the system, which weighs them directly into pouches. The pouches are then sealed,checkweighed and cartoned.

A presentational challenge

For Tommy Guldborg, technical processing engineer at Tulip Food Company,the main purpose of the new line was to improve product presentation.

"When packed by hand, the sausages had to be lined up by the operator.This was not a very accurate process. Combined with the variation insausage length and curvature, this led to a need to allow quite a lot ofextra length in the flow-wrapped pack. Apart from wasting film, thisdetracted from the appearance of the product in the bag," Guldborg said.

The new 14-head Ishida has an extra-wide infeed chute, in order tocapture the disordered stream of long sausages. The dispersion table isspecially shaped to prevent backward movement, and so keep the productmoving outwards along the radial feeders. A load cell, built into thedispersion feeder table, controls the infeed rate.

The radial feeders are equipped with fins to help channel the sausagestowards the pool hoppers. The large (7-litre) pool and weigh hoppers are fitted with inserts tohelp align the sausages. Each weigh hopper discharges into a narrow, dedicated chute with a ring shutter at its end to align the sausages in the right direction, and tobreak their fall. They are released into a special lower dischargechute, whose parabolic shape further aids correct alignment. A stainlesssteel anti-crash pole suspended in the middle of the chute reducescollisions between sausages coming from different directions.

Vibratory alignment system

The sausages from different weigh heads meet in the weigher's vibratoryalignment system. This is a progressively narrowing set of funnels, eachvibrated mechanically and blocked by a pneumatically-driven gate at itslower end. The effect is to further align the sausages, and to linetheir lower ends up precisely as they approach the bagmaker.

Special count-priority software ensures that each bag contains the correct number of pieces.

The packs produced by the new line are neater and more compact inappearance. The sausages are more prominent and better aligned.

"The consumer is unlikely to be interested in the fact that we now putless film in the pack," said Guldborg, "but he or she will noticethat it looks and feels neater and more solid."

Cost savings

While this was a move to improve the pack rather than to save money, it has cut costs considerably, Ishida claims. The length of each bag has been reduced by 30mm, and its width by 45mm,giving a saving on film of €34,000 per year.

The more accurate weighing achieved by the Ishida is calculated to havereduced giveaway per sausage by about 1 per cent. This amounts to about €45,000 savings per year.

On top of all this, the considerable reduction in manpower achieved byautomating the line has enabled the company to redeploy skilled staff elsewhere in the business.

Packing, using a flow-wrap approach, needed a staff of five. Bycontrast, only two people are needed on the new line now.

"The sausage market is strongly seasonal," said Guldborg. "It canbe almost twice as big in the summer, when people eat hot dogs on thestreet and in their summerhouses. With an automated process, we will nothave the same problem of finding and training temporary staff during thesummer."

Ishida Europe is a world leader in the design, manufacture andinstallation of complete weighing and packing line solutions for thefood industry. Headquartered in Birmingham, UK, supported by four additional offices inmainland Europe, one in the UAE and one in South Africa, the company's2002 sales reached £41 million (€67.1m) in Europe, Africa and the Middle East.Ishida Europe is a subsidiary of Ishida in Japan.