Identifying Bottlenecks

Identification an characteristic of bottleneck

After the initial substantive preparation, a brainstorming tool was used to develop a checklist before introducing the SMED method. This list was intended to illustrate the actual state of the situation and to present all aspects to which the team should pay attention during the visit to the production hall during changeover. After making the checklist, the team equipped with a video camera went to the production line and hall and proceeded to the re-documenting and all operations carried out during the change. The culmination of this stage was the development of a preliminary division of duties and a detailed determination of the project's objective.

On the base of this analysis and discussion of the team the main bottleneck was identified in the research. It was reduction of the changeover time to 18 minutes. All the times values in this paper were multiplied by a constant factor.

The characteristic of the process identified as a bottleneck was subsequently made. The analysed production process takes place at the pipe production department. The specification of this line, depending on the reference produced, may require the use of a maximum of seven machines. On of this machines is so called RZ - is responsible for more complex calibration operations, such as the creation of outlets (exhaust system ends).

The necessity of using so many machines requires very good organizational preparation before it starts. Also communication and experience from the rudders and foremen is needed. However, the analysis of the film showed that not everything works as it should, because the total changeover time was 3h 52min. This is a very big result, especially since the line overwhelms an average of 1.5 times during one shift, which during the whole day (the company is working on 3 shifts) gives 16h and 14min of line stoppage. This is a huge loss for the company, ignoring the fact that the main assumption of SMED is to achieve the changeover time with the value of a one-digit unit of time.

After the initial analysis of the film, it was noticed that the main problem in the retooling of the above-mentioned machines lies on the side of the bending machine, whose total changeover time amounted to 2h 14min and partly on the RZ side.

For all other machines, the changeover time is adequate to the time specified in the instructions and is relatively short, as it is within 10 - 18 minutes. In addition, the specification of machines is so simple that the possibility of introducing any improvements is impossible. The only machine, as already mentioned, which in addition to the bending machine requires special attention is RZ. This is due to the fact that the retooling process of this machine in a very blatant manner contradicts the principles of ergonomics, which is why this issue certainly needs to be analysed and implemented. In addition, the time of its retooling also exceeds the limit according to the methodology, as it amounted to as much as 2h 28min.