23 August 2002

Spud cost cuts in bag

In a bid to reduce potato

growers costs, Higgins

Agriculture has developed a

bulk bagging system which

uses a revolutionary design

of trailer. Geoff Ashcroft

saw the system in operation

LOOKING to take some of the costs out of growing potatoes while maintaining a margin for its 300 or so contract growers, specialist potato merchant Higgins Agriculture has developed a new bagging system which, it claims, has revolutionised the way potatoes are moved from field to store.

Three years in development, the Higgins potato bag trailer collects and bags the crop directly from the harvester, allowing potatoes to be easily rehandled and transported to store.

The system is believed to contribute towards reducing haulage costs and maximising output at a time of year when traditional bulk trailers are in high demand.

"Haulage costs keep rising due to the specialist nature of bulk potato trailers, so we aim to keep a lid on those costs by handling our crops in 1.3t bulk bags, which allows produce to be transported in a standard curtainside lorry trailer," says Higgins Agricultures commercial director John Pettinger.

"It also means harvesting wont come to a standstill while growers are waiting for bulk trailers to remove their crops from the farm. They can keep harvesting the crop into bags, then holding them ready to load on to a lorry."

The 13t capacity trailer, a joint development between Higgins Agriculture and engineering firm Haith Tickhill, uses a central hopper that is divided into 10 funnelled sections, five on each side of the trailers body. And beneath each funnel is a 1.3t capacity bulk bag.

"The system is geared for easier road transport," says Mr Pettinger. "Up to 22 bags of potatoes can be moved by articulated lorry, which helps to maximise payload for the haulier."

In operation, the trailer body is filled with potatoes in its lowered position for in-field stability, with the bulk bags folded up beneath each hopper. No potatoes enter the bags at this stage.

Once filled, the trailer is taken to the headland or yard to find a suitable hard-standing area where bag filling can start.

Filling the bags requires the trailers body to be raised by four hydraulic rams – one on each corner of the body – and an on-board pto-driven hydraulic system ensures tractor hydraulic capacity is not critical.

As the body is slowly raised, crop gently flows into the bags below. When full, the bag carrying arms are extended from beneath the hopper to position the bags clear of the trailer. Lowering the body then places the bags on the ground.

At this stage, the arms are retracted allowing the trailer to be driven away from the filled bags. Empty bags are then loaded on to the arms before the body is fully lowered to allow the filling operation to be repeated.

Mr Pettinger says the system has resulted in reduced crop handling before the potatoes are put into store, so reducing the opportunities for damage.

"At every stage of the bagging process, the crop is handled very gently. There are no drops other than from the harvesters elevator into the trailer."

Bagged off field

Of the 400,000t of potatoes marketed annually by Higgins Agriculture, Mr Pettinger reckons about 40,000t are bagged off the field during harvest, with a further 90,000t bagged out of store.

At the other end of the process, unloading the bags also required an engineering solution. Haith Tickhill produced a 360í rotating drum into which a bag is loaded by forklift. Hooks are attached to the base of the bag before the drum is rotated to invert the potato bag and empty its contents. This cycle is completed in about 60 seconds, enabling almost 80t/hour to be unloaded.

"When harvesting has finished, the bag filling trailers are utilised at our stores to allow graded and washed crop to be rebagged and distributed to processors throughout the winter," he says.

Higgins Agriculture now has a fleet of 17 bagging trailers, which it supplies to its growers.

"Our bagging system should eliminate some of the capital expenditure new growers need to get involved in potato growing by bagging the crop in the field and taking the crop to our stores, growers no longer need to invest in grading lines to grow potatoes.

"As a result, we aim to reduce existing grower costs and attract new growers into potatoes to help secure our supply chain business," he says. &#42

1) The trailer is filled with potatoes directly from the harvester, as any conventional trailer would be.

2) Back at the farmyard, the entire trailer body is gently raised to allow the crop to flow into the 10 bags below.

3) With the body fully raised and all bags filled, the yellow arms that carry the bags are pushed out to prepare the bags for lowering.

4) The body is then lowered to place two rows of five bags on the ground on either side of the trailer.