Ingenieur Vol 61 January-March 2015 | Page 72

INGENIEUR In this way, action can be taken before a deficiency occurs. Figure 4 shows a typical control chart. Figure 4: Control Chart ii. Quality circle group or formation of small group of shop floor employees. This initiative was championed by Toyota who believes employees working at production lines know the work and process best. Therefore, they should be empowered and encouraged to recommend quality improvement as part of their work assignments. Employees are not considered as just workers but as members of an improvement team. They are encouraged to contribute ideas and recommend actions to reduce defects as well as to improve productivity. External Failure cost (EF-cost) EF-costs are those costs incurred when deficiency is found after delivered to customer. It includes warranty costs, compensation costs, after service costs and business trip expenses to send staffs or engineers to support customers on quality issues. At times when deficiency is too serious, the entire product batch is returned and the cost involved is also considered in the EF-cost calculation. The main factors that contribute to EF-costs are human or equipment errors that lead to defects slipping through to the customer. Therefore, the following quality improvement initiatives should be implemented: i. Institute regular training programmes to upgrade operator skills and knowledge, followed up by practical tests to ascertain their competency level. Only operators who pass the test and are certified should be allowed to work on the production line. In this way, defect creation and slippage to downstream processes or the customer can be controlled. 6 70 VOL 61 JANUARY – MARCH 2015 VOL 55 JUNE 2013 ii. Wherever possible, manual work should be automated to help establish quality consistency and avert human error. This initiative may incur additional expenditure but will result in long term quality improvements which may more than cover the initial investment cost. iii. Periodically flow dummy defective test parts through defect filtering process or machine in order to instil quality awareness among operators and evaluate the reliability of machine performance. The ultimate objective is to stop defective parts at the processing station and avoid slippage through to the customer. Appraisal cost (A-cost) Appraisal costs include all those costs involved in measuring, evaluating or auditing product components and purchased materials to ensure they conform with the standards and specifications. These appraisal activities generally require human effort. As such, the cost of quality inspectors or personnel who are assigned to perform the following activities: i. Incoming quality inspection of raw materials and/or parts, ii. Outgoing quality inspection on finished goods before shipment, and iii. Quality inspection gates inside the process or production lines These constitute a large portion of A-cost. Other components of A-cost are fees paid to the quality standard or product safety regulatory bodies ( ISO, BSI, CCE etc) that audit and issue certificates of compliance to the company. Quality improvement initiatives for A-cost are mainly to cut down inspection tasks and reduce the number of inspector positions. These may include: i. Engaging and supporting material suppliers in improving their quality systems which will result in then delivering quality materials, thus eliminating or minimising incoming quality inspection tasks. ii. Streamlining all inspection tasks and eliminating any redundant ones. Value stream mapping technique (Rother & Shook, 2003)