| CU Company is a wholly-owned subsidiary of Caterpillar,which mainly produces track group and track roller products of excavator chassis.More than 95% of its employees are recruited from outside.After the trial operation,due to periodic adjustment of construction machinery,the capacity utilization rate and personnel allocation rate are only 30%.Until the arrival of a new round of explosive growth of construction machinery,CU company began to recruit a large number of employees,and suppliers began to expand production capacity.Faced with the rapid increase of output and personnel,CU Company’s product quality problems also showed explosive growth,and its quality management urgently needs to be improved and solved.By means of questionnaires and statistics and analysis of index data,it is found that CU company mainly has problems in the following aspects: First,front-line employees have weak quality awareness and insufficient ability to prevent defects,resulting in rework of the subsequent process and more customer complaints.Secondly,due to the lack of clear description of employees’ problems,timely feedback of problems and insufficient experience of engineers in analyzing and solving problems,there are many repetitive quality problems in the production and manufacturing process.Thirdly,the supplier only has the basis of ISO9001 quality system and lacks actual quality management methods,which leads to the poor quality of the supplier’s incoming materials.Aiming at the above problems,this thesis applies lean thinking,combines the existing quality problems of CU company,and improves the traditional quality management mode of CU Company by referring to the nine steps of lean quality framework.Under the theoretical framework of "Built in quality" Lean quality method(BIQ),the use of special process data statistics and analysis(SPC),6Sigma DMAIC and other commonly used lean quality management tools,combined with Caterpillar lean production 3 subsystems,15 guidelines,In particular,the process improvement dialogue(PID),visual management and other basic lean principles have systematically improved the staff’s ability to prevent defects,describe problems,trace defects,communicate feedback and analyze and solve problems.In CU company,I have explored and run a set of systematic and practical lean quality management methods.After the improvement,the rejection rate per million products PPM decreased from 439 to 54,the unit product defect DPU improved by 59.6%,and the poor quality cost improved by 29%.In addition to the improvement of the main quality indicators,the training and certification process of employees has been reorganized and refined through the improvement project,and the management process of first-line monitor and supervisor has been established,so that employees can systematically and quickly master the necessary knowledge of the post,adapt to the post requirements,and improve the ability to prevent defects.In addition,the supplier quality performance management and improvement process was established,and the new lean quality management method was introduced into the suppliers with poor performance to help them improve their quality management level.The quality performance of the pilot suppliers was improved from 2780 to 390.In this case,aiming at the main prominent contradictions existing in the quality management of CU Company,the lean quality method is used to improve the overall improvement effect is very obvious.This also proves that the lean quality management method studied in this thesis plays a significant role in improving the quality.By optimizing the quality management method of pilot production line,this thesis points out a set of effective and defect-free improvement scheme for manufacturing enterprises.At the same time,it also provides a reference for the effective application of lean thinking in the manufacturing process of enterprises. |
