Quality is Main Criteria
Quality is Main Criteria
The main product quality criteria are an operational reliability indicator.
We have talked to Lyubov Nefedova, Statistics Analysis and Reliability Group manager, about electric multiple units (EMU) quality assessment at Demikhovo Engineering Works (DMZ).
– Ms Nefedova, what does product reliability mean?
– Regarding electric multiple units, it means a characteristic to perform certain functions during the specified period of time or mileage. The requirements to EMU, including ones to their reliability, are set in technic specifications approved by the customer. The main EMU reliability indicator is a so-called meantime between failures. The parameter conformity is evaluated on the basis of train operation results within the warranty period, i.e. during next two years after the products being delivered to the customer.
– What does the EMU operation reliability depends on?
– It depends on its design, maintain- and reparability, materials quality, manufacturing and assembly processes, quality control methods, technological processes management, test methods, operational conditions, and approved maintenance and repair system.
– Concerning our plant, how is the EMU reliability evaluated, what is the key factor for the EMU no-failure operation indicator?
– The enterprise that operates the EMUs provides us information about non-compliance with the quality criteria and then these data are to be registered in the Information System and to be analysed. Up to 98% of these non-compliances occur due to the low quality of the purchased components provided by our suppliers. In order to achieve the best results, it should be done the following: first, to choose suppliers able to satisfy our plant production needs to the maximum; second, to conduct work on the quality enhancement with our suppliers constantly.
– How can we affect the purchased components quality?
– In 2010 at DMZ was created a working group, whose task is to conduct work with our suppliers. This group consists of specialists from each division of our plant. The main objective is to determine activities that let us to increase the reliability level. This should be done on basis of comprehensive quality assessment of purchased components and for this purpose it was revised and approved the Regulation on Purchased Products Quality Management Working Group #P 0710.020-2017, which includes a supplier assessment method.
It should be pointed out that the suppliers’ reliability ranking is to be formed on basis of 8 indicators scoring system that considers a legal liability level, product life cycle cost calculation availability, supply organization level, provided documents, reliability indicators, defects identification while verifying and testing the products, as well as a meeting of troubleshooting deadlines after a particular product being commissioned.
When the comprehensive assessment is completed, each supplier gets a category: ‘competent’, ‘acceptable’ or ‘incompetent’.
With regard to the incompetent suppliers, it is necessary to determine corrective actions, whose efficiency is defined by an imperfections reduction dynamics.
– What else affects the reliability of manufactured products?
– I’d like to point out a subjective factor that affects the production: this factor is our numerous team efforts. Each team member has responsible approach to one’s job: from maintenance to support services. As a matter of fact, it’s a part of the positive image of Demikhovo Engineering Works.