Angle of groovingWear and breakages

Angle of grooving
Wear and breakages of the teeth increase when the angle of grooving is decreased, but to
a smaller extent than was supposed until 1955. When there is no reason for adopting a more acute angle, a value of about 55° is employed. American factories sometimes adopt 45-50 a value which may be recommended. However, it is the Australians who in about 1956 — 58 adopted the greatest innovations in this matter. While they had already long used an angle of 35°, they found, when aiming to allow the grooving of the top rollers to fill with bagasse ("dirty top roller"), that the angle of the grooving had a marked influence on the packing of bagasse in the roller grooving. At the feed roller, Donnelly1 specifies 30°, this angle being sufficiently acute to prevent the bagasse from penetrating to the bottom of the grooves, under the low pressure at the feed roller; the groove thus acts as its own Messchaert groove for draining the juice.