12 May 1995

Constant wrapping – in all weathers

AN electromagnetic braking unit, from P J Parmiter, is designed to overcome the problem of under-wrapped silage bales in hot weather, writes James de Havilland.

Geoff Burgess, managing director of the Wilts-based firm, explains: "The warmer it gets, the narrower the neck of film being drawn from the wrappers reel. With a conventional stretching system, this leads to a reduced film overlap on the bale. The operator can compensate by putting on an extra wrap, but in practice this seldom happens." Incorporating an electromagnetic brake, which acts on the reel spindle, the Auto Stretch unit automatically alters the amount of force needed to pull film from the reel according to the temperature.

In warm weather, when the film stretches more easily, the unit compensates by reducing the braking on the reel spindle. Should it get cooler, the brake will progressively apply to restore stretch to the desired level. Consistent film overlap is, therefore, maintained automatically, the operator simply setting the desired level of stretch. The Auto Stretch system will not be offered as an option on the Parmiter SR52 Square Bale Wrapper, because the strain gauge used to monitor tension on the film reel spindle can only work vertically. But it is available now as a retro fit kit for Parmiter wrappers made after 1992. Kit price is £1450, or £1050 when selected as an option on a new wrapper. &#42

The warmer it gets the easier the stretch. Parmiters Auto Stretch unit automatically compensates for different types of weather.