Converting to a Pull (Kanban) System

Problem Description

Real Seating manufactures car Interiors has decided to convert their operations to a pull system. You have been charged with determining the Kanban size and Kanban Trigger for all five products (RF RR LF & LR doors and Instrument Panels). Additional information includes:

1. Please use Cycle Time, cart size, and cycle time data from Lab Models 01 & 02.

2. The current Color mix for all products is 40% Blue, 30% Red, 20% Black, and 10% White. Product is run in batches of the same color at the Cutting operation, generating carts with parts all of the same color. While at Assembly operation, parts are pulled from the incoming cart individually, and the outgoing cart has parts representing a mixture of colors.

3. Change over between colors at Cutting is uniformly distributed with a range of 50-60 minutes. Change over occurs when the color being processed at Cutting changes.

4. A product is released to the cutting cell for production when we have accumulated 4 Kanban cards of a specific color. (Kanban Trigger = Lot Size = 4)

5. Set initial inventory levels to 2 carts of each color at the in-line buffers, and 4 carts at the queue between cutting and assembly (WIP). (Kanban Size = Max Inv Level = 6)

Your goal is to design a system that balances Throughput with WIP size. In addition to identifying optimal system design for the current color mix (specified above), please do same for the following 2 color mixes:

• 25% Blue, 25% Red, 25% Black, and 25% White.

• 10% Blue, 15% Red, 25% Black, and 50% White

As you perform your analysis, include the following metrics, and identify/use other metrics as appropriate.

• Utilization for Cutting and Assembly operations (by color)

• Maximum and average WIP size (by color)

• Number of completed good parts per hour (by color)

Listing of What If? scenarios for which the simulation model was developed.