11 April 1997

Setting a standard for hopper design

CHEMICAL induction hoppers are now a standard fitment for the vast majority of sprayers. Some work well, others do not.

But that could soon change. According to Lurmarks sales director, Ian Sutton, a new British Standard is soon to be implemented – BS6356 part 8, published last November – which sets out certain build and operating criteria for such units.

Armed with such information, it is perhaps no surprise that Lurmark now claims to have built the first induction hopper to meet all the new demands.

And the Clean Load does appear to offer some neat features. Constructed from polyethylene, it comprises a circular, cone-shaped hopper with a watertight lid. Chemical placed in the hopper is drawn into the main tank by a venturi created by a flow of water delivered from the pressure side of the pump.

In the bottom of the cone is a plastic helical nozzle on which bottle foils can be pierced – the contents pouring into the venturi. For rinsing, the bottle is pushed down on a T-bar which allows water to be sprayed up into it; washing is assisted by a rotating impeller within the bottle.

Pretty basic so far, but it is the way the hopper handles water soluble bags that is perhaps its greatest attribute. Rather than dropping such packages into a tank and hoping they dissolve before they arrive at the pump, they can be dropped into the hopper, the lid shut and squirted with water until they have dissolved.

Water is powered both upwards from the helical nozzle and downwards from a bank of nozzles in the lid. To operate the lid must be closed.

One final feature is a system to draw liquids or powders into the hopper through a lance. One end is pushed over the helical nozzle to allow it access to the venturi suction and the other placed in the bag or can as required. To help with the flow and mixing of the material, a small water pipe feeds water into the venturi. Price of the Clean Load is £495.n

Chemical induction hopper of the future? This Lurmark build claims to be the first design to meet a new British standard.