P13711: Wegmans Dough Mixing Process Improvement
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Build, Test, Document

Table of Contents

During MSD II our focus was the implementation of the downtime clock, QA indicator, and all associated testing and refinement. The quarter began with the final schematic approval of the devices, bidding/pricing by Atlas, and the installation of the devices. Concurrent to the installation we optimized the production floor (mixing, QA, and packing) worker scheduling to ensure maximum support during packing times that require additional processes (such as the Safe Food Quality metal detection checks), and created a documentation/reporting system to assist management in operationalizing daily performance. After the installation of the device, testing was conducted to ensure accuracy. Reporting and documentation was completed for several weeks to lead discussions for future areas of improvement. The full sequence of MSD II events and activities have been documented below.

Build, Test, and Integrate

Downtime Timer System

Components:

Wegman's already has the PLC and Dough Divider in their current system. The only addition we would make is the installation of the timer. Wegman's will also take care of reprogramming the PLC and the dough divider.

PLC Programming Steps:

  1. When the dough divider is in RUN mode, the downtime timer will not be running.
  2. When the dough divider is in STOP mode, the downtime timer will be running.
  3. When the dough divider returns to RUN mode, the downtime timer will be paused.
  4. The downtime timer will have a manual reset with an automatic backup reset set to a time determined by Wegman's.
  5. The downtime timer will be a running tab style timer.
Downtime Timer Wire Diagram

Downtime Timer Wire Diagram

Downtime Timer Location

Downtime Timer Location

QA Indicator System

Components:

As mentioned above, Wegman's already has a PLC.

PLC Programming Steps:

  1. If necessary add an I/O card for the new discrete input(Elevator Switch) and output(Audio/Visual Indicator) to the existing PLC.
  2. When the elevator switch is tripped, a signal will be sent to the PLC.
  3. The PlC will start an internal timer for 10 minutes.
  4. At the end of the 10 minutes, the PLC will send a signal to the QA indicator.
  5. The QA indicator will stay on for 5-10 seconds.
  6. If the dough divider is in STOP mode the internal timer will be paused.
  7. The internal timer will continue when the dough divider returns to RUN mode.
QA Indicator Wire Diagram

QA Indicator Wire Diagram

QA Indicator Location/Structure

QA Indicator Location/Structure

Elevator Switch Location/Structure

Elevator Switch Location/Structure

Test Plans & Test Results

MSD II Test Plan.docx

Documentation and Reporting

Operators will be responsible for filling out the documentation form after every recorded downtime. Each downtime will be recorded on the clock and must be given an associated downtime code. An example form is displayed below.
Example of what the downtime recording sheet looks like after it's been filled out by the operators

Example of what the downtime recording sheet looks like after it's been filled out by the operators

Management will be trained on the use of a spreadsheet that will take the operator's form input and output trending pivot tables and graphs with respect to production date or product. This tool will help provide a transparent view of the line's performance. The full document is linked at the end of this section. A screenshot of the tool is below. Note: these data are only an example and does not translate to actual recorded information.

Excel sheet for management to enter data

Excel sheet for management to enter data

Below is an example pivot chart that shows production date daily downtimes. This chart will trend over time to show increases or decreases in operational performance. These example data were pulled from the input above.

Automatic pivot chart showing daily downtimes by production date

Automatic pivot chart showing daily downtimes by production date

Below is an example pivot chart that shows downtimes associated with each product. This chart will trend over time to show increases or decreases in operational performance. These example data were pulled from the input above.

Automatic pivot chart showing varying downtimes by product

Automatic pivot chart showing varying downtimes by product

Spiral Downtime Recording Document.xlsx

Pre-device Test Plan

The following pre-device installation test plan was created in order to test the feasibility, effectiveness, and quality of the proposed devices. The final implementation is to be seen through by Wegmans as the test results proved the device to be high-quality, effective, and robust across all products. The documentation provided above and on subsequent pages also proved beneficial and easily used by both floor operators and management.

Interim test plan while device approval/installation is delayed

Interim test plan while device approval/installation is delayed

Testing Data Collection

Below are some sample data files from the device pre-installation tests that were conducted through MSD II.

TestData.xlsx

Test #1 Summary 3/27/2013

Testing result summary from 3/27/2013

Testing result summary from 3/27/2013

Test #2 Summary 4/12/2013

Testing result summary from 4/12/2013

Testing result summary from 4/12/2013

Test #3 Summary 4/19/2013

Testing result summary from 4/19/2013

Testing result summary from 4/19/2013

Test #4 Summary 4/26/2013

On Friday 4/26 a full ergonomics analysis was conducted in the mezzanine using one of the heaviest bread products, pumpernickel bread. This analysis was to evaluate the impact of gapless production on increased worker fatigue and physical excursion. The test was led by Nancy (Wegmans ergonomisist). In addition, Standard Operating Procedures now reflect the need for all remix bins to be emptied prior to mixing each new batch. This should help much of the variability that has been see during other product tests.

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