Journal of Oil Palm Research Vol. 11 No. 2, December 1999, p. 114-122 ABDUL RAZAK Jelani*; DESA Ahmad**; AHMAD Hitam*; AZMl Yahya**; JOHARI Jamak*
A Study was conducted to investigate the effect of cutting angle and from maturity on the specific reaction force (ROCSA) and energy requirement (RENCSA) for cutting oil palm fronds. A spring powered sickle cutter was used in the experiment. The experiment conducted was to determine the magnitude of reaction force that would be transferred to the harvester in the cutting operation. Cutting angles of 90º, 60º, and 45º were tested on the three levels of frond maturity (F1, F2 and F3).
Experiment carried out showed significant effects of cutting angle on the ROCSA and RENCSA but not by frond maturity. Increasing the cutting angle from 45º to 90º increased the ROCSA to about 72%. The maximum and minimum values of ROCSA were 24.5 N cm-2 and 10.8 N cm-2 respectively.
The ratio of reaction force to the maximum cutting force (R/Fcmax) was also studied. The ratio gives the percentage of cutting force being transferred to the harvester during the cutting process. It was found that R/Fcmax was significantly affected by the cutting angle and frond maturity. The maximum and minimum ratios were 35% and 14% at cutting angles of 70º and 45º for cutting F3 a d F1, respectively.KEYWORDS:
* Oil Palm Research Institute of Malaysia,
P.O. Box 10620, 50720 Kuala Lumpur, Malaysia.
** Universiti Putra Malaysia,
43400 UPM Serdang, Selangor, Malaysia.