Designed for N.Z. conditions

Press, 23 September 1983, Page 25

Designed for N.Z. conditions

The many methods of distributing water for irrigation are well represented in New Zealand, according to Mr D. J. Hawke, the sales manager for B. R. Homersham, Ltd. ;/ “For many years there has. been a need fdr a machine designed to cope with New Zealand conditions,” said Mr Hawke. “Most, if not all, irrigation machines were developed overseas and do not suit our methods of agriculture and land development. “Take, for instance, the centre pivot and power-roll systems, both ideally suited to the large wide acre situations in the United States. “Used in New Zealand conditions, however, their lack of portability shows up as a problem,” said Mr Hawke.

The Turborain, designed and manufactured by Homershams, is ideally suited to New Zealand conditions, according to Mr Hawke.

The irrigator is totally Sortable, can be operated y one man, operates with either high, medium or low pressure, can irrigate from headland to headland, covers up to 12 hectares per day, can operate in very windy conditions, can distribute liquid fertiliser, arid is reasonably priced, he said.

The Turborain has been designed as a multi-role boom irrigator. Most are ordered in the low pressure range (down to 70 k.p.a.). The use of Class B pipe, small electric motors and pumps, and lower power consumption make the low pressure models the iriost popular option. In a situation where conditions were favourable, a Turborairi had been fitted with a sjnglephase electric motor which enabled the operator to benefit from low energy costs. Other models range from 140 k.p.a. to 690 k.p.a. which distribute the same amount ii ■ ■■—-

of water, but over a greater area.

The maximum area covered by a high pressure Turborain would be about 24 hectares per day. The actual wetted area at any one instant can be as much as 1.785 hectares resulting in very low application rates. The Turborains can be tailored to meet any specification relating to application or filtration rates.

Rotating systems can have inherent weaknesses when it comes to uniform application of water across a property, said Mr Hawke. “In fact on all irrigators it is not until the back of the wetted pattern crosses the front of the wetted pattern that full irrigation takes place.” The low pressure Turborain, with its static boom, keeps the under-irrigated areas to 0.09 per cent of the property. A rotating system would miss or under irrigate 44 per cent of the area in d similar situation.

Low-pressure machines have been ordered for use on market gardens, dairy farms, tree nurseries, and cropping and mixed farms. Their low centre of gravity makes them suitable for rolling country, and there are some Turborains operating in the Maniototo area of Central Otago, where other types of machines could never work successfully, said Mr Hawke.

The Turborain uses a drag hose to reticulate the water from the hydrant to the machine. This hose is rated at pressures well in excess of those used in irrigation and has a special fabric framework giving it high tensile strength and a lifetime of 15 years.

The distribution boom of the Turborain can be made in several lengths, the most common being 100 m. With the low pressure model, a wetted strip 100 m wide by 600 m long can be covered in 12 hours.