Search Filter
- Publications
- Abstract of Theses and Dissertations
- Database
- Harvesting Conditions Affecting the Threshing of Palay
Harvesting Conditions Affecting the Threshing of Palay
Thesis Abstract:
The study was conducted to determine the effects of palay harvesting conditions, baesd on grain moisture content, on the performance characteristics of six different rice threshers and on the threshing quality of palay.
Results indicated that the performance of each type of threshers was significantly influenced by varying levels of palay harvest conditions. At lower levels of moisture content more threshed, semi-threshed and unthreshed grains and grain losses. The optimum grain moisture condition at harvest seemed to be at 18 to 23% wet basis.
The hold-on fed threshers gave more threshed, semi-threshed and unthreshed grains but less grain losses than the throw-in type machines. For hold-on feeding, the wire loop threshing cylinder exhibited the best overall performance, followed by the peg-tooth and the rasp bar cylinders. However, for throw-in feedning, the latter two were better thatn the former.
At any level of palay harvest conditions. threshing drum speed was optimum at 1800-2000 feet per minute for hold-on and 4500-5000 for throw-feeding.
The quality of threshed grain was significantly realted to the level of grain moisture content at harvest. Higher threshed garin recovery, greater purity percentage and better threshing efficiency were obtained with lower grain moisture condition.
The throw-in threshers produced better quality of threshed grain than the hold-on type, partly on account of the difference in the feeding method.
At all levels of moisture, conditions, the peg-tooth threshing drums, with either feeding method, yielded the best quality of threshed grain, while the rasp bar, hold-on type gave the lowest.