Submitted to: National Cotton Council Beltwide Cotton Conference
Publication Type: Proceedings
Publication Acceptance Date: 2/1/2012
Publication Date: 4/20/2012
Citation: Porter, W.M., Wanjura, J.D., Taylor, R.K., Boman, R.K., Buser, M.D., Barnes, E.M. 2012. Tracking cotton fiber quality throughout a stripper harvester. In: Proceedings of the Beltwide Cotton Conferences, January 3-6, 2012, Orlando, Florida. 2012 CDROM. p. 522-533. Interpretive Summary: Stripper harvested cotton receives price discounts from end users due to high levels of foreign material and fiber entanglements (neps). The goal of this work was to identify components and systems on a cotton stripper harvester that, if redesigned, could improve seed cotton cleanliness and better preserve fiber quality. Seed cotton samples, hand harvested in the field and collected at five sequential locations on a cotton stripper harvester, were analyzed for foreign matter content and fiber quality. Seed cotton total foreign matter content was highest after the stripper rolls before the cotton was conveyed out of the harvesting units by the row unit augers. The row unit augers decreased total foreign matter content in the seed cotton by removing a substantial amount of fine trash comprised mostly of soil and small plant parts. Total foreign matter content remained at a consistent level during conveyance by the cross auger until the harvested seed cotton was processed through the field cleaner. The field cleaner decreased total foreign matter content by removing burs and some fine trash. Leaf grade and AFIS (Advanced Fibre Information System) trash and dust content measurements follow similar trends where parameter levels increase on the stripper from the stripper rolls until the inlet to the field cleaner. Leaf grade, AFIS trash, and AFIS dust content were decreased by the field cleaner back to levels observed just after the stripper rolls. Fiber quality analysis results indicated that the harvesting and conveying systems on the cotton stripper did not have a detrimental impact on fiber length characteristics or on the formation or size of neps. The results of this work indicate that the cross auger and pneumatic conveying systems on stripper harvesters could be redesigned to help improve seed cotton cleanliness while helping to preserve fiber quality.
Technical Abstract: It is known that cotton fiber quality begins to degrade with the opening of the boll. Mechanical harvesting processes are perceived to aid in fiber degradation. Previous research indicates that stripper harvested cotton generally has lower fiber quality and higher foreign matter content than picker harvested cotton. The main objective of this project was to track cotton fiber quality and foreign matter content throughout the harvesting units and conveying/cleaning systems on a brush-roll stripper harvester. Seed cotton samples were collected at six locations including: 1) hand-picked from the field, 2) just after the brush rolls in the row unit, 3) just after the row units, 4) from the separation duct after the cotton was conveyed by the cross auger, 5) from the basket with the field cleaner bypassed, and 6) from the basket after the cotton was processed through the field cleaner. Seed cotton samples collected at each location were analyzed for foreign matter content and ginned to produce fiber for HVI (High Volume Instrument) and AFIS (Advanced Fibre Information System) fiber analyses. Results show that the row unit augers and field cleaner aid in reducing the overall foreign matter content, effectively increasing the gin turnout to that of hand harvested cotton. AFIS and HVI results indicate that the harvesting and conveying systems on the stripper have a minimal effect on fiber length characteristics and the formation and size of neps. Leaf grade increased between the harvesting units and the field cleaner due to the breakup of foreign material caused by mechanical action. The field cleaner helped to reduce leaf grade back to the level observed at the stripper rolls. The results of this work indicate that the cross auger and pneumatic conveying systems on stripper harvesters could be redesigned to help improve seed cotton cleanliness while helping to preserve fiber quality.