Maintenance systems all over the world aim at high reliability and availability of equipment and other assets. Other objectives of maintenance systems include:
- · Reduction in production loss (due to unplanned stoppages)
- · Extended productive life of assets
- · Higher resale value
- · Safety
- · Lower cycletime of diagnosing the equipment failures and repairing and restoring equipment to health
- Avoiding surprises
- · Higher productivity and efficiency of equipment
- · Reduced setup delay and losses due to lowspeed operation of machines
- · Lower overall operational expenses, inclusive of cost of maintenance.
- · Reducing the loss due to catastrophic failure of equipment
Total quality management (TQM) has been applied successfully for maintenance systems, in order to improve its effectiveness. The concept of TQM has an interesting history.
At the end of the Second World War, in order to minimize delivery of defectives to customers, producers began to emphasize stringent norms for finished goods inspection. However this caused a rise in rejection rate and cost of goods increased.
In order to reduce the production of defectives, producers began to improve quality at the manufacturing stage. The success was limited, because experience told them that many defects were caused not due to manufacturing stage, but due to defective design itself.Now the companies realized the need to improve quality company wide, improve everything that company did.
Soon it was realized that defects were contributed by parts bought from vendors. In order to involve everybody within in the organization as well as with the vendors the new concept was named total quality management. These concepts were initially introduced in Japan.
Quality management system
In order to ensure consistent quality output, through TQM, throughout the organization, International standards organization introduced three new standards, viz. ISO 9001, ISO 9002, and ISO 9003 forthe implementation and certification of quality management systems. These standards were later combined into a single standard: ISO 9001 certification.Process approach was adopted for improvement of quality in every business activity. ISO 9001 Consultants continue to play an important role in the application of TQM, and successful implementation of ISO 9001.
Two distinct approaches of TQM concept implementation emerged:
· Continuous improvement approach through quality circles (small group activity) at grass root level, and
· Cross functional quality improvement teams (of experts), who try to improve quality through breakthrough solutions, which result in quantum jump in overall performance.
TQM methodology involves four sequential stages, known as PDCA cycle:
In the planning stage, the team of people, identifies the problem to be solved and collectsfactsand data, and use the TQM tools such as
- Brain storming
- · Fish bone or Ishikawa diagram (Cause-effect relationship diagram)
- · Control charts
- · Check sheets
- · Pareto analysis
- · Histogram
- · Scatter chart
- · Process flowchart and
- · Stratification
Based on the root cause analysis done by using fishbone diagram, solutions are planned in this stage. Best solutions are determined and implemented in the Do stage.
During the Check stage, the team determines the measurements to decide the effectiveness of the solution implemented,and confirm the effectiveness.
In the Actstage team prepares the document of changes and the results, communicates to others in the organization so that solution can be adopted on companywide basis. Necessary training is given. Based on the experience gained, next cycle of PDCA is initiated to ensure continuous improvement on a sustainable basis.
Aviation sector, among others, has reported successful implementation of TQM for improvements in maintenance.Benefits reportedinclude enhanced safety, reduced cycle time of fault diagnosis and repair activities as well as reduced down time.Latest quality improvement techniques now being adopted include business process re-engineering(BPR), adoption of best practices(BP) and benchmarking(BM) as well as six sigma approach to fine tuning the processes.