Zero Defect Planning of Case Hardened Transmission Gears - A Case Study

Abstract:     
Defect abatement is the most vital activity for any metallurgical engineer (Thareja, 2006). It is so because an unscheduled incidence of defects causes delays, disposal of defected inventories and dumping of plans and schedules of deliveries. A defect is virtually a denial of promise, which puts plans haywire (Thareja, 2008). The planning of defects free production is therefore very important (Thareja and Goyal 2005). This work is intended to implement the rigour in case of transmission gears for Tractors. The gears undergo distortion during case hardening and heat treatment. The work reports improvement in the Composite error achieved significantly after heat treatment, which varies with the changes in the hardenability of steel used for Internal gears. All in all the results of ten case studies have been reported. The Various recommendations to zero defect planning include agenda to lower the quenching temperature, Raising of the quenching oil temperature, Lowering of the austenizing or carburizing temperature etc. Implementation of various action schemes lead to reduction of defects to zero levels (Thareja and Goyal 2005).

Number of Pages in PDF File: 14

Keywords: Quenching, Tractors, heat treatment, carburizing, failures, steel

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