TPT November 2017

T E CHNOLOG Y

Quality management for highest reliability ISO 9001 is an international recognised standard in quality management. Since 1993 Sikora has been certified according to this standard, which proves that the quality of the measuring, control, inspection, sorting and analysis technology at the company is efficient and that the quality management system (QMS) is continuously improving. be evaluated and it can be monitored precisely how long devices operate without failure. shows if events of one device occurred immediately after delivery or at a later date. When certain events accumulate to a cluster above a certain delivery date, meaning events that had not occurred before to this extent, this can indicate that the production process was not controlled well at that time, or else sourced materials had caused a higher failure rate.

MTBF is calculated by using the information from Sikora Customer Relationship Management (CRM). This is where all devices are registered and their events are recorded. CRM also serves as data source for the creation of event diagrams for the different types of devices. The event diagram is a graphical illustration for quick and clear visualisation of events and their chronological order. Furthermore, the event diagram provides details concerning the type of individual events for a certain device type. An event diagram has horizontal (x) and vertical (y) timelines. The x-timeline shows the delivery date and the y-timeline shows the event date. The diagram indicates all known downtimes of one device type up until time of creation, as shown in the example. Events are counted that directly led to a downtime of a device. Deliveries of all devices are displayed as crosses on the diagonal line of the diagram. On the vertical line above each delivered device, its life span can be seen. In the event of failure, a certain symbol is noted on the vertical above the device, which gives information about the reason of the failure. In order to display device downtimes, symbols are used for hardware events (Δ), software events (◊) and others (x) (eg production errors, faulty deliveries, etc). The event diagram (as shown in the example) primarily serves to find out which event types have occurred. It also

Furthermore, event diagrams for certain failure types are created and differentiated according to the different components, to collect further details of the device events. This includes, for example, diagrams that only refer to device events where hardware components contributed to a failure rate. All other failure types (mechanical failures, software failures, etc) are shown in a separate diagram. In this way, detailed information is given about which component relates to the documented events. The second factor, which is incorporated into the calculation of the availability, is the MTTR. This is calculated from the time that is needed to put the device and the system back into operation in the event of failure. Thanks to quality management and technical innovations, which render maintenance of Sikora devices almost unnecessary, high availability values of up to 99.98 per cent are reached. For continuous quality improvement, internal and external employee training is carried out at Sikora. Furthermore, co- operation with machine manufacturers, as well as customers, is established in order to respond to global benchmarks in the trade and to further optimise processes. “A sustainable quality management requires clear, transparent processes and a good communication,” explained Mr Heel. “Feedback from employees and customers in particular is crucial for a successful qualitymanagement system,” he explained. “With the improvement of our operation processes according to the requirements of our QMS, we do not only meet legal standards, but also achieve a high process reliability and, simultaneously, the highest customer satisfaction.”

Sikora’s QMS is composed of defined performance indicators in order to monitor and control processes. ‘Availability’, for example, is the time value in which the machines and technical measuring devices can be in use without downtime or maintenance. “The monitoring of the achieved product quality is the prerequisite to meet our customers’ requirements regarding a product or service,” said Arne Heel, quality manager at Sikora AG. In conjunctionwith themanagement and employees, he analyses and records business processes within the company and identifies responsibilities and potential weaknesses. For the visualisation of availability as a key figure of product quality Sikora creates event diagrams to clearly present the device performance, to help draw conclusions on the process quality. For calculation of the availability, two factors are considered: mean time between failures (MTBF) and mean time to repair (MTTR). The first factor, MTBF, describes the mean time in which a device can be in use without the need of a repair or downtime for maintenance. With the help of MTBF, the quality progress can

Sikora AG – Germany Email: sales@sikora.net Website: www.sikora.net

Visualisation of availability by event

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NOVEMBER 2017