PREVENTIVE METHODS IN LOGISTICS POKA-YOKE …

1 1. Stefan SCHMIDT. PREVENTIVE METHODS IN LOGISTICS POKA-YOKE AND. FAILURE MODE AND EFFECT ANALYSIS (FMEA). 1. PROCESS AND QUALITY MANAGEMENT, UNIVERSITY OF APPLIED SCIENCES AND VWI (GERMAN ASSOCIATION FOR BUSINESS. ADMINISTRATION AND INDUSTRIAL ENGINEERING), FRITZSTRASSE 41, D-82140 OLCHING, GERMANY. ABSTRACT: PREVENTIVE METHODS are seldom used in LOGISTICS , although there is increasing awareness of their potential. This paper presents two examples of PREVENTIVE METHODS currently in use, POKA-YOKE and FMEA (Failure Mode and Effect Analysis). The implementation of POKA-YOKE , the mistake proofing methodology, has been shown to drastically reduce the enormous warranty costs, including LOGISTICS costs, while FMEA, implemented for the purpose of assuring the smooth execution of industrial processes, has already been successfully applied during the early planning phase of a new packing centre under construction.

2 KEYWORDS: PREVENTIVE METHODS , LOGISTICS , FMEA, POKA-YOKE , industrial application INTRODUCTION Good POKA-YOKE devices, regardless of their In German industry, quality costs are estimated to particular implementation, share many common be, on average, up to five to ten per cent of the characteristics: turnover. This corresponds to 36 to 72 billion Euros. They are simple & cheap. If they are too 70 per cent of these quality costs represent the costs complicated or too expensive, their use will not involved in correcting defects, while only seven be cost-effective. percent are prevention costs (quality inspection). They are part of the process, implementing what PREVENTIVE METHODS are seldom used in LOGISTICS and Shingo calls "100%" inspection.

3 Warranty generates huge costs for handling and They are placed close to where the mistakes transport. This paper shows, on the basis of occur, providing quick feedback to the workers, so industrial examples, that the mistake proofing that the mistakes can be corrected. methodology, POKA-YOKE , drastically reduces the This paper shows, on the basis of industrial enormous warranty costs including LOGISTICS costs. examples, that the mistake-proofing methodology, In addition, a second preventative method, FMEA can POKA-YOKE , eliminates the cause of an error at the be implemented for the purpose of assuring the source by detecting any error as it is being made or smooth execution of industrial processes and has soon after it has been made, but before it reaches already been successfully applied during the early the next operation.

4 POKA-YOKE helps to build quality planning phase of a new packing centre under into processes and products. As a result, the construction. In this way, possible failures and their enormous warranty costs, including LOGISTICS costs, causes and potential effects, as well as measures to will go drastically down. be implemented for the avoidance and detection of POKA-YOKE training programme such failures, can be analysed from the aspect of For the employees, the Target of the POKA-YOKE failure mode factors. Training is to develop a POKA-YOKE mindset and gain MISTAKE PROOFING METHODOLOGY POKA-YOKE practical experience in the implementation of poka - POKA-YOKE is a Japanese term that means "mistake- yoke .

5 The Target group includes planning engineers, proofing or "fail-safing". This concept was formalised quality engineers, employees in problem solving and the term adopted by Shigeo Shingo as part of the process and specialists in charge of POKA-YOKE Toyota Production System [1, 2]. The target is to solutions . avoid missing parts, misassembled parts, incorrect The Training Concept is the communication, in an processing and incorrect parts. almost playful manner, of the POKA-YOKE theory and The definition of POKA-YOKE = Error Proofing: includes a high proportion of practical exercises. The POKA-YOKE is a device, which prevents a process exercises are based on real production problems and from making an error (prediction) or a defect focus on Process- POKA-YOKE .

6 The trainers conduct from being passed on to the user (detection). practical exercises during which they act as coaches. When a defect is predicted or an error detected, The results of these exercises are then presented to the process is shut down or a control prevents the the management for their implementation. For the process from going ahead or a warning is sent. implementation of POKA-YOKE as a new methodology, copyright FACULTY of ENGINEERING HUNEDOARA, ROMANIA 27 ACTA TECHNICA CORVINIENSIS Bulletin of Engineering a training programme has been developed. Table 1 quality, which leads to higher customer satisfaction, shows the agenda and table 2 the key lessons of a see figure 1 [3].

7 POKA-YOKE training programme. Table 1 Agenda POKA-YOKE training programme DAY 1 Theory: Simulation: POKA-YOKE Training Station POKA-YOKE Theory - Flip Chart Training 5 Shingo plants, product- & process- poka - yoke , Attributes of good POKA-YOKE solutions etc. Examples: videos and several solutions for production problems presentations POKA-YOKE exercises (on paper). Basics of the problem solving process Organisation day 2: Formation of teams, introduction of several production problems DAY 2 Practical experience: Teams select 3 problems each (missing, wrong, Figure 1 - Engine sensor installation with multiple loose), data acquisition POKA-YOKE applications Teams discuss each of these problems and then, The expanding network size of logistical systems as a Selection of one production problem and one result of outsourcing and internationalization also solution for cardboard simulation leads to less reliable processes that are more prone DAY 3 Practical experience: to error.

8 Increasing transport distances, network Teams implement the solution in a simple partners distributed throughout the world and the cardboard simulation rise in the number of LOGISTICS interfaces lead to Preparation of a presentation for management more unstable material flows. Error-tolerant logistic Teams present results processes can, however, be achieved with the aid of Agreement for the handover of results to the POKA-YOKE solutions, as shown by the following production line examples (figure 2): POKA-YOKE shelf in automotive final assembly line Table 2 Key lessons of a POKA-YOKE training [4]. programme Error-free order picking with POKA-YOKE : in this Key lesson 1: Introduction to POKA-YOKE example, the POKA-YOKE concept is realized Key lesson 2: How three types of POKA-YOKE through the use of Pick-by Light or Put-to Light detect and prevent errors in a production with sensor monitoring of the removal and system, the contact method, the fixed-value storage places as well as RFID-monitoring of the (or constant number) method and the motion- conduct of the process.

9 As a result of this step (or sequence) method implementation of POKA-YOKE , the number of Key lesson 3: How Quality can be built into order picking errors are reduced by 80% to 95%. products by the implementation of POKA-YOKE compared to paper-based systems [5]. Key lesson 4: How POKA-YOKE helps build quality Increasing Efficiency of Warehouse Operations [6]. into processes by equipping forklifts with PCs: an affordable Key lesson 5: How the growing relevance of solution for many new and existing warehouses is POKA-YOKE improves warranty and reduces costs to empower operators by installing an onboard including LOGISTICS costs. computer on each forklift and connecting them to Industrial POKA-YOKE examples a Warehouse Management System (WMS) via a A Motor Company and Bosch Rexroth Corp.

10 Have wireless local area network. This makes the implemented multiple error proofing applications to location of items and empty storage space identify different sensors based on their torque immediately visible, which instantly reduces the signature: waste involved in transportation, human motion POKA-YOKE #1:Torque Red/Green Light display and waiting. This results in better response times POKA-YOKE #2:Screen Display (less waiting) for dependent production processes POKA-YOKE #3:Sensor control for long/short sensor and customer satisfaction. A shorter lead time selection provides an improved service and can also result POKA-YOKE #4:Alarm signal if the wrong senor in a reduction of inventory and floor-space selected requirements.