DEVELOPMENT OF A HIGH-CAPACITY EXTRACTOR CLEANER FOR COTTON STRIPPER HARVESTERS: MACHINE DESIGN AND OPTIMIZATION

Cotton stripper harvesters have used extractor-type cleaners for many years to remove large foreign material from seed cotton. These machines are commonly referred to as "field cleaners" and are similar in design and operation to stick machines used in cotton gins. The field cleaners used on modern cotton strippers are capable of processing burr cotton at the harvesting rate of four-row strippers but are overloaded when used on strippers with six- and eight-row headers. The objective of this work is to report on the design and optimization of a new field cleaner with improved cleaning performance and processing capacity. A 0.305 m (1 ft) wide prototype machine was constructed and used in a response surface experiment to optimize cleaning performance and lint loss. Predictive equations were developed using five configuration factors: loading rate per unit width, primary saw cylinder speed, reclaiming saw cylinder speed, primary saw grid spacing, and reclaiming saw grid spacing. As observed in previous work, the results indicate that a balance must be reached in the trade-off between maximizing cleaning performance and minimizing lint loss. The results also indicate that the experimental machine is capable of reaching 60% cleaning efficiency but that additional design modifications and testing are necessary for the machine to reach the lint loss design goal of less than or equal to 1%. Keywords. Cleaning, Cotton, Harvesting, Stripper, Trash. tripping is the predominate cotton harvest method used in the Texas High Plains region. Cotton strip- pers were developed as a cost-effective alternative to picker harvesters for gathering the High Plains crop, which was characterized by relatively low yields (414 to 807 kg ha-1 (0.77 to 1.5 bales ac-1)), short plant heights, and storm-proof boll conformations that held mature seed cotton tightly inside the open burr (the term "burr" refers to the dried carpel segments of the cotton boll). Historically, picker harvesters were much less effective at harvesting the High Plains crop due to the storm-proof nature of the bolls (bolls are the segmented fruit of the cotton plant containing locks of seed cotton) and short plant stature. However, new cultivars with improved yield potential and fiber quality properties are being introduced to the region. Today, it is not