Ashok Sarkar

ESTIMATION OF PROCESS CAPABILITY INDEX FOR CONCENTRICITY

Concentricity of any hollow circular or cylindrical job is a critical quality characteristic whose variation pattern can be explained by an extreme value distribution. Estimation of the process capability index is a prerequisite for control and improvem..

Implementation of ISO 9000 in a textile mill

ISO 9000 quality systems have been developed to provide necessary conceptual and structural input for fulfilling customer needs by ensuring consistent and desired product quality. It is necessary to have an implementation plan, the success of which depends on top management involvement from the beginning. Consultants can also play a major role in this implementation programme. Effectiveness of a system can be judged by higher customer satisfaction through increased employee involvement and product quality improvement. This case study deals with formation of road map, implementation details, road blocks and tactical steps to remove the road blocks, in implementing ISO 9001 within 12 months and achieving better quality product in a textile mill.

Application of Six Sigma to improve the quality of the road for wind turbine installation

Purpose – The purpose of this paper is to apply Six Sigma methodology, a systematic and structured approach for quality improvement in wind energy sector. This paper discusses the development of sustainable wind farm roads for an organization engaged in manufacturing, installation and servicing of windmills in India.Design/methodology/approach – This paper illustrates the Six Sigma DMAIC approach and its application for development of sustainable wind farm roads.Findings – The systematic and data driven approach of Six Sigma methodology identified many root causes for road damages and solutions were implemented to ensure sustainable wind farm roads.Originality/value – Six Sigma has been successfully implemented world over in different business processes ranging from manufacturing to service and health care. However its application is very uncommon in areas like road construction. This article demonstrates the applicability of Six Sigma methodology in uncommon areas.

Improvement of service quality by reducing waiting time for service

Abstract One of the major concerns of any service organisation is the time customers have to spend waiting for service. As is well known, waiting time depends on a number of quantities, such as the system arrival rate, service rate, type of services, time of the day, and efficiency of the servers. In this paper, we propose a service model appropriate in the Indian banking industry and discuss the effectiveness of various solutions using simulation. The best solution found from the alternatives has been implemented. In this paper, we summarize the efforts and the results thereof.

Selection of critical processes for “process improvement”

Purpose – The purpose of this paper is to develop a criterion for selection of critical sub‐processes when all the sub‐processes cannot be taken up simultaneously for improvement. There exist various methods but the practitioners get utterly confused because of the existence of these multiple options. In this paper, the goal is to assist practitioners in the selection of the critical sub‐processes.Design/methodology/approach – The authors discuss various statistical methods such as correlation and regression, simulation, basic statistics such as average, standard deviation, coefficient of variation % (C.V.%), etc. for the selection and identification of the critical sub‐processes. The strengths and weaknesses of these methods have been compared through empirical analysis based on real‐life case examples.Findings – The stepwise regression and simulation have been found to yield identical results. However, from the perspective of application, stepwise regression has been found to be a preferred option.Origi...

Issues in Pareto analysis and their resolution

Vilfredo Pareto established the ‘Pareto principle’, which is also known as ‘vital few, trivial many’, to help in identifying ‘vital few’ errors for problem-solving. However, in many industrial applications, issues such as (a) the incorrect selection of the ‘vital few’ errors, (b) the interrelationship among errors and (c) the merging-up errors of different processes together need to be addressed. Otherwise, the chances are pretty high that the application of Pareto analysis will fail to correctly identify the ‘vital few’ errors, leading to an incorrect problem-solving approach. In this paper, the authors demonstrate the issues with the help of a real-life case study in a service scenario and suggest the appropriate remedial measures, for effectively separating out the ‘vital few’ causes from the ‘trivial or useful many’ causes to enhance the discriminating power of the Pareto graph.

Process Control and Evaluation in the Presence of Systematic Assignable Cause

A process is assumed to be free from assignable causes of variation while evaluating its capability. There are processes where variation occurs due to assignable causes which have to be tolerated. Traditional methods for process control and process capa..

Developing a model for process improvement using multiple regression technique

Purpose – Practitioners often face challenges in model development when establishing a relationship between the input and output variables and their optimization and control. The purpose of this paper is to demonstrate, with the help of a real life case example, the procedure for model development between a key process output variable, called the multi-stage flash evaporator efficiency, and the associated input process variables and their optimization using appropriate statistical and analytical techniques. Design/methodology/approach – This paper uses a case study approach showing how multiple regression methodology has been put into practice. The case study was executed in a leading Indian viscose fiber plant. Findings – The desired settings of the relevant process parameters for achieving improved efficiency have been established by appropriately using the tools and techniques from the Lean Six Sigma tool kit. The process efficiency, as measured by M3 of water evaporated per ton of steam, has improved ...

An outline of the “Control Phase” for implementing Lean Six Sigma

Purpose – The purpose of this paper is to develop a guideline of the control procedure and tools depending on dominance pattern. In Lean Six Sigma (LSS) implementation, the control phase plays a vital role in sustaining the gains achieved from the improvement phase. The process control schemes should be developed by studying the process dominance pattern as suggested by Juran. Design/methodology/approach – Discussion has been made on identification of various methods with the help of a few real life examples for effective LSS implementation. Findings – The dominance pattern helps in identifying the control mechanism. However, with the advent of new business processes, the dominance pattern needs a little bit of modification. Research limitations/implications – The case studies mainly are from the manufacturing sector and one from the service sector, where authors have studied the control mechanism. There exists scope of future research in service sector for adequate representation. Originality/value – The...

STUDY ON IMPROVEMENT OF BLOW-ROOM PERFORMANCE

In spinning mills, the blow room is the first of several processing stages of operations. Here, compressed cotton is opened and cleaned of impurities. The degree of cleaning achieved in the blow room influences the yarn quality. This performance is meas..