Development of Automatic CTC Roller Chasing Machine

U. Datta, R. Lanjewar1, G. Balamurugan, A. J. Banerjee, P. Saha and S. Sen

ABSTRACT: The tea produced by the process of crushing, tearing and curling (CTC) of tea leaf is commonly known as CTC tea and the processing unit as CTC machine. The preprocessed tea leaves are fed into CTC machine wherein a pair of rollers called CTC rollers, having uniform teeth along the circumference, is running in close proximity at different speeds to make CTC tea as final product. Combination of annular concentric grooves and helical grooves result in the formation of the CTC roller teeth. The circular grooves are machined on the rollers with a chaser tool on a special purpose lathe and helical grooves are milled on a special purpose milling machine. After continuous use, the teeth of the rollers undergo wear and deformity and therefore, they need to be reconditioned /resharpened. At present, chasing operation on CTC tea rollers are done on machines which are operated manually. Thus accuracy of chasing is not satisfactory. The accuracy of the teeth on the rollers has a great effect on the quality of tea leaves. Improved accuracy and productivity can be achieved by introducing automatic control. This paper describes development of control system of an automatic chasing machine of CTC Rollers.

KEYWORDS: CTC Machine, Chasing, Tea Rollers, Automation, Control, Cutting Forces

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