Title: Development of a high-capacity extractor cleaner for cotton stripper harvesters - Machine design and optimization Authors
Submitted to: Transactions of the ASABE
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: December 5, 2009
Publication Date: December 23, 2009
Citation: Wanjura, J.D., Holt, G.A., Byler, R.K., Brashears, A.D., Baker Jr, R.V. 2009. Development of a high-capacity extractor cleaner for cotton stripper harvesters: Machine design and optimization. Transactions of the ASABE. 52(6):1821-1829. Interpretive Summary: Stripper type cotton harvesters collect considerably more foreign material in the harvested seed cotton compared to picker type harvesters. The foreign material is made up of plant parts (leaves, sticks, burrs, etc.), soil, and other material and contaminates ginned lint resulting in reduced quality and monetary returns for producers. In response, producers have adopted the use of field cleaners to help remove the majority of the foreign material on the harvester before the seed cotton reaches the gin. With increasing yields and acreages farmed per producer, it has become common practice to use stripper harvesters with six and eight row wide headers to increase harvesting productivity. The field cleaners used on cotton strippers are not sized according to the size of the header. Thus, a common 1.52m (5 ft) wide field cleaner has been used on all commercially built strippers since the early 1980's. The feeding rate into a 1.52 m wide (5 ft) field cleaner processing cotton from an 8 row wide header is approximately 2.5 times the recommended processing rate. Overloaded field cleaners do not clean cotton as efficiently as when not overloaded and tend to throw out excessive amounts of useable cotton. Thus, the objective of this work is to report on the design and optimization of a new field cleaner for use on stripper harvesters with improved cleaning capability and increased processing capacity. The results of the tests show that the new machine can reach cleaning efficiencies in the design goal range of 60% but further design modifications are needed for the machine to reach the lint loss design goal of 1% or less. Additional testing is planned to refine the performance models developed in this work and to evaluate the improvement in lint loss from modifications to the machine.
Technical Abstract: Cotton strippers have used extractor type cleaners for many years to remove large foreign material from harvested seed cotton. These machines are commonly referred to as "field cleaners" and are similar in design and operation to stick machines used in 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 wide 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%.