Growth in Inventory Control Using Supermarkets

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Lastly, an understanding of supermarkets and their associated symbols are essential to conducting this study. The effectiveness of a supermarket depends heavily on inventory and storage. With a wide variation of model specific parts being delivered from similar locations, product organization is vital. Rother and Shook (2003) explain in their book, Learning To See, that supermarkets control production, at the supply process, without trying to schedule. The book continues by giving specified guidelines on how to conduct pull systems using supermarkets. The book gives detailed illustrations of sample supermarket systems and their associated symbols. Certainly, understanding supermarkets and their guidelines is critical to conducting this study.

In conclusion, the references found all aid in conducting a kaizen of the current supermarket. The references outline continuous flow, supermarkets, kaizen definitions, and process guidelines. Complete understandings of these aspects are principal to completing and effective study.

Method

In response to the need for continuous improvement onsite, a study was conducted to:

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Validate various kaizen theories learned within the Engineering Technology

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Reduce the amount of time it takes for material deliveries to be completed

To conclude the study, a quantitative research project was initiated to track specific quantities of part deliveries and their times to validate the need for internal supermarkets. The methods used in this study are based off of the theories developed by the forefathers of lean thinking.

Participants

This study aims to use kaizen theories to assist in controlling flow from the warehouse to the production floor. Participants in this study consisted of 179 repair technicians, both contract and permanent, from the production floor. All active repair technicians within the department were a part of this quantitative study. All participants are current employees, and were not compensated for this study. Technicians request parts and materials to be hand-delivered from the warehouse and/or supermarket locations. Depending upon the specific model of the unit being repaired, certain parts are requested more often than others. There were thirteen part-delivery employees present during this study. Additionally, there was one Industrial Engineer to assist in data analysis and time studies. All participants were asked to arrive prompt at the appropriate time, which allows all data collection to begin at the same time daily.

Apparatus/Materials

In the present study, data collections consisting of serial numbers, part numbers, pick locations, and dispatches were obtained via Microsoft Excel. In order to analyze data provided from the warehouse and production floor, a laptop was provided. Each repair technician is housed with a Dell computer, equipped with RFID scanners for part consumptions. Additionally, there were 8 supermarkets that generate and capture part orders directly from the production floor. Each supermarket is constructed using insulated foam and Creaform. Each current supermarket houses 15 out of the total 19 parts needed for each model.

Procedure

Once all of the units were received, a repair technician was tasked with ordering the necessary parts required to troubleshoot and repair the unit. The parts order is then printed from the associated supermarket or warehouse location. The deliverer then scans the pick ticket in order to subtract the part from inventory. The same deliverer then hand-delivers the part to the technician who requests it. The part is then consumed using the RFID scanner at the repair technician’s location. This calculates a pick time and a delivery time that can be exported via Microsoft Excel. In theory, the time of this delivery should be as short as possible.

There were eight supermarkets initially housed on the production floor. The warehouse stores the bulk of the high demand parts. Hence, the parts that are ordered more often are being received from a farther location. It was hypothesized that the addition of supermarkets that house “high demand” parts would be beneficial to part runners, and eventually reduce the time of part deliveries. The units per hour calculation were approximately 5% higher than the threshold. To further the current hypothesis, the researcher constructs additional supermarkets on the production floor. The additional supermarkets are implemented to reduce the amount of walking required to deliver high-demand parts. Each unit completed is extracted to an external report for documentation purposes. This report contains the dates, durations, and quantity of units completed during the selected time period. After the initial report is collected, the enhanced supermarkets were introduced and implemented. The same report used to extract the initial data is used to extract the post-implementation data. Finally, analysis of the initial quantities of completed units versus the post-supermarket employment is conducted.

Results

A preliminary analysis of the current production floor layout indicated that a reduction in square feet is vital to the enhancement of the department. The initial square feet value was measured at approximately 62,900 sqft. By rearranging the production layout and supermarket locations, the square feet value has been reduced to 19,500 sqft, a (69%) improvement. Additionally, the implementation of supermarkets for the current proposal yielded a reduction in daily warehouse deliveries. Initially, the warehouse delivers approximately 1,500 parts daily, depending on the unit inbound. The implementation of supermarkets on the production floor reduced the amount of deliveries from 1,500 to 326. This reduction accounts for a $1,408 in savings per month. The implementation of supermarkets on the production floor accounted for a (78%) decrease in warehouse deliveries. Additionally, a units-per-hour metric was calculated to illustrate cycle time improvement within the production floor (see Appendix A for more information on the units-per-hour data). The production floor has improved its cycle time by (33%) Please refer to Figure 1 for UPH illustration.

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Figure 1: Final vs Initial UPH

Thus, these results provided some evidence that supermarkets