Wegmans Dough Mixing

Wegmans Dough Mixing

Project P13711

Nick Gianelle

Becca Hendrix

Matt Purcell

Clayton Tontarski

Table of Contents

Abstract:

Introduction:

Methodology:...... 3

Results:...... 5

Conclusion/Recommendation:...... 7

Acknowledgment:...... 9

Abstract:

Wegmans Food Markets, Inc is a retail grocery chain that produces many items in their Rochester, NY bakeshop. One specific process yields the frozen dough of subs, bagels, and various breads that get shipped to individual stores. Wegmans has been experiencing heavy fluctuations in throughput. This variability in productivity came from a multistep process where cycle times of each step differ, therefore, it was necessary to coordinate and synchronize the steps relative to each other. Visual, electrical, and mechanical aids were explored as possible aids to the process. The design and implementation of a device allowing Wegmans transparency into downtimes, capacity losses, and accurate quality assurance tests experienced by this process is reported here.

Introduction:

Wegmans Food Markets, Inc is a retail grocery chain with 82 stores in the northeast. Wegmans produces their old fashion sub rolls and bread dough in Rochester, NY in the form of frozen dough to be baked by the individual stores. Wegmans has seen a significant increase in the demand of this process recently. Wegmans has been forced to work employees in overtime shifts to accommodate the increased demand. Wegmans originally believed that the problem rested on the lack of employee controlled performance and the lack of real-time process feedback to show whether they were ahead or behind schedule. However, as observations and analysis concluded other sources of variation and areas of opportunity existed, the scope of the project began to shift to general process improvement.

After the refinement of the project scope the project focused on the design and implementation of two devices. The first was a downtime clock to give management a tool to better understand the capacity limiting events that occur during the day. The second was a quality assurance indicator, to give operators a tool to convey new batches to the dough cutter and freezer without needing a gap between them to differentiate the two. These two devices aim to fulfill the project objective of designing and implementing a means of increasing product throughput and awareness to events that cause reductions in productivity.

Methodology:

The first step in the process improvement was to evaluate the current state of the system. Analyzing a baseline process was essential to making changes to achieve the overall goal. It was assumed by management that the problem rested in the mixers not being able to meet set time goals. Another assumption and limitation was that the team focusedprimarily on sub rolls and assumed any feasible ideas were possible solutions.

The first experiment conducted was an overview of the frozen dough process as a whole. The objective was not clear to start with because management thought the reason for the inefficiency of the frozen dough process was due to the operators lacking incentive. After going to the bakery and observing the process a number of times the team determined that the actual problem was not the operators but the process used to separate each batch. The operators were putting approximately a minute gap in the production line for separation. This was taking away an hour and a half of production each day, yielding a theoretical 12% reduction in throughput.

To validate the hypothesis the team recorded the time from the beginning of a new batch to thetime the dough was dumped into the large hopper. Management had an approximation of how long this process should take. After examining the data, the team determined that these time goals were not being met. This was a big problem for management because the production schedule was based on these times. With the addition of the one minute gaps being purposely put into the production line, the ability for Wegmans to meet their production quota was lofty.

Immediately it was determined to remove the minute gap used to separate each batch. In order to do this the team had to prove whether or not the packaging side of the production line could handle the constant flow of product. The team took time studies of the mezzanine packing processes and found through simulation techniques that with a few changes it would be possible to eliminate the gap between batches. Figure 1 is a visual model the team developed of the production floor for this area in the bakery that was used for the process evaluation and simulation.

Figure 1: Production layout

Additionally, a full internal ergonomics evaluation was also conducted to ensure the increased work would not result in excess fatigue or cumulative trauma disorders. Some of these changes would be switching the printer from a batch numbering system to a time system and having another employee do the remedial chores such as cleaning and filling the box maker. These changes to ensure feasibility came primarily in the form of process improvements and the creation of best practice instructions.

From the above experiments the team determined the customer needs were to automate the batch separation process without stopping the production line and to develop a feedback system for management. To automate the batch separation process the team designed an indicator light system. One specification needed for this system was the time it takes the dough to travel from the large hopper to the end of the production line. In trying to meet Wegmans’ demands the team came up with a design involving a light and sound signal. This signal would be located near the QA position and would alert the assigned employee when to remove and tag a sample for testing.This signal would be triggered eight and a half minutes after the dough trough contacts the limit switch located at the tipping point of the elevator.

The feedback system the team designed utilized a downtime clock that recorded the amount of time the divider was not running. In other words, it recorded the cumulative count of lost throughput time on the frozen line. This was accomplished by connecting the divider to an LED display clock. When the divider is in ‘STOP’ mode, the downtime clock will start. When the divider returns to ‘RUN’ mode, the downtime clock will pause until the next time the divider is in ‘STOP’ mode. The downtime clock wouldallow managers to come by the production line and see if there had been any stoppage in production. Subsequently they would be able to check the developed documentation that gave reasoning as to why the production line had been stopped.

Unfortunately the installation of these components was not done during the active project timeline due to the significant cost and approval process delays. To validate the ordering process, the teammanually ran the system by using timers and stopwatches to replicate what these two systems would do. The data was consistent with what the teamexpected to see if the two systems were installed. There was a large reduction in the amount of downtime and the production line was able to run smoothly with no gaps in the line.

Results:

As a result of many hours of time study and observation the team discovered that there was room for improvement by eliminating the gap that was put between batches on the production line. At the Systems Design Review, it was discussed that thedowntime is used for the employees to complete auxiliary tasks during the time.The team and Wegmans decided to do some observations and make a list of the tasks done and to see what could be eliminated. Figure 2 below lists these tasks and the amount of time the employees spent on each one.

Figure 2: Mezzanine duties and time spent on each

Going forward the team designed a simulation of the process using Arena software, which was used to determine whether the employees in the mezzanine area could handle the loss of the downtime between batches without falling behind in packing. Based on the results of the simulation it was established that the mezzanine was capable of handling the capacity of constant work flow. It was also decided that a timer LED display clock that displayed and counted the times and durations of when the process saw downtimes would be a helpful tool for management. By doing this, the team would have the ability to track machine failures or change-over times. At the Detailed Design Review it was decided that the downtime timer clock should be installed first.This would provide insight, when the new quality process was established,as to how much downtime was saved. Following the Detailed Design Review the design team came up with a full bill of materials for all of the hardware that would be needed to execute the plan, as well as a schematic of where the visuals should be installed on the Wegmans production floor. The design and bill of materials was proposed to Wegmans and Atlas Automation, a third party vender.

Due to the cost estimate that was given by Atlas Automation, additional lead time was needed in order to go through the procurement process for Wegmans to get approval for the high cost of the equipment. During this time, both the design and Wegmans team agreed that some pre-installation testing should be done. This would also help with the cost justification process. During the first test, the team led the Wegmans team in eliminating the gap between batches for the duration of ten batches consecutively. The team also helped train management and floor operators on the new downtime documentation. During this time it was observed that the average time between batch dumps was 13.1 minutes (historically 15.4 minutes). The time decided that QA would pick a sample was 10 minutes and 30 seconds after that batch was dumped into the hopper. There was no instance observed when the next batch was dumped before the 10 minutes and 30 seconds was up. It was also observed that the remix was generally lower than numbers the team had seen in the past and exceeded no more than 47.6 pounds and caused no more than an extra 2 minutes and 52 seconds to a batch. It was also noted that there were no instances of downtimes recorded during this time. Upstairs in the mezzanine it was noted that the average time between the Safe Quality Foods (SQF) metal detection check was 30 minutes, and the average duration to complete the checks was 41 seconds, causing minimal accumulation on the conveyor. Other observations include, the average time between box maker issues was 22 minutes, and the average time to fix the issue was 123 seconds, the build-up on the conveyor took approximately 1 minute to recover from. There were no instances during this time of a conveyor stop or any downtimes.

The second round of testing the average time between batches being dumped was 10.1 minutes for the Italian dough and 11.6 minutes for the caraway rye dough. The quality assurance checks were done at 8.5 and 9.5 minutes, respectively. Neither type of dough saw any instance where the next batch was dumped prior to the QA indicator being alarmed. Upstairs in the mezzanine saw that there was an overall average of 30 minutes between each SQF check, and that the average time to complete an SQF check for the Italian dough was 70.6 seconds while for the caraway rye it was 79.4 seconds. On this day, no major issues were noted. The only downtime recorded downstairs was due to product changeover, and it was observed that the box maker was very inconsistent however it did not cause any belt stops from upstairs.

On the third day of testing the products that the team observed were wheat sub rolls and caraway rye bread. The average time between dumps for wheat subs was 15.8 minutes with the minimum being 14 minutes and the maximum being 17 minutes. However, on this day the cut speed was 70 cuts per minute rather than the usual 90 cuts per minute. For the caraway rye dough the average time between dumps was 12.3 minutes where the minimum was 11 and the maximum was 13 minutes. In the mezzanine the average time between SQF checks were 26.3 and 27 minutes for wheat and caraway respectively, while the average time to complete the checks for wheat was 58 seconds and for caraway it was 72.3 seconds. Table 1 summarizes the key metrics yielded from the pre-device installation testing.

Table 1: Summarized Pre-Device Installation Results

After, a graph showing the reductions in batch cycle times for each preliminary product testing was formulated. The average reduction which directly relates to increased daily throughput is displayed in figure 3:

Figure 3: Preliminary Batch Cycle Time Reductions

Lastly, Wegmans had an internal ergonomics assessment conducted in the mezzanine to ensure the safety of the employees with the potential increase in hourly work caused by removing the gap between batches. The team helped conduct the assessment but did not specifically report on findings by the ergonomists during the project timeline.

Conclusion/Recommendation:

The project had many successes and failures throughout its lifespan. One success of the project was the use of general observation, simulation software, and time study to justify the implementation of our two recommended systems. These industrial engineering techniques were essential in convincing Wegmans of the current status of their dough mixing process and ensuring them that the system is capable of achieving higher output. Another success of the project was the design of systems to record the downtime of the system and also indicate when QA samples should be picked. These systems give visibility to the employees on the floor about how well the line is running and ensures each batch is sampled for quality. Without these systems, the dough mixing process would not be able to remove the delay between batches and thus would be stuck with the 12% reduction of throughput each day.

The biggest issue with the project was the underestimation of the cost of implementing the systems. Costs include not only direct monetary burdens but also the time required to approve the devices and then implement them. Due to the large costs, the group needed to develop tests to assess and mimic the capabilities of the system without the devices while still removing the gap between batches. Team members needed to simulate the devices’ functionality to help the process run as prescribed. Although this was useful in proving the hypothesis that the system was capable of the increased capacity, it did not allow for testing of the actual devices to ensure the system can run continuously without supervision. Instead, testing was conducted with team members emulating the devices functionality to ensure the constant workload could be handled by all employees.

Based on the issues faced during the project, the team now realizes a few things that could have done differently. One of the biggest issues involved device validation and selection. If the team were to restart the project, more focus would be placed on ensuring that there is enough budget for the project and enough evidence of its effectiveness to make sure the device would be implemented in a timely manner. More research should have been done to ensure that the recommended devices were reasonable in price.

Another improvement to the project would have been to develop a stronger risk assessment along with contingency planning. Not anticipating the delay in devices, the team was caught off guard and unsure which direction to take the project until a few days of brainstorming. If the team had anticipated the possibility of this delay the group could have been more prepared for the preliminary testing and spent more time brainstorming other possible actions to take while waiting for the implementation of the devices.