design_lean_sysm - Massachusetts Institute of Technology...

Info iconThis preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
Massachusetts Institute of Technology Leaders for Manufacturing Program Use of a Queueing Model to Design a Lean System Prepared as a basis for class discussion by Jamie Flinchbaugh 1 . Toyota has evolved the design of their vehicle assembly plants for 50 years. Much of the work coincided with the development of the Toyota Production System 2 and has evolved through periods of trial and error. In this case, with the corresponding model found in lean_factory.xls , you have the opportunity to use a queueing model to explore the relationship that Toyota discovered when developing the Toyota Production System. A brief explanation of the factory dynamics In a factory using the andon process 3 , buffers are used to create independence among departments attempting to push decision making further down in the hierarchy and create mini-companies within the factory. This is attained by physically promoting significantly more independent departments or line segments than a traditional assembly plant would have, as depicted in the figure. A line segment may consist of somewhere between 20- 40 workstations. Separating each line segment is an accumulating buffer that can hold several work cycles of product. The buffers allow each of the teams to make decisions regarding stopping the line to fix problems. The buffers also increase the independence in operating metrics. These buffers seem to violate the principle that inventory is waste and should be eliminated; instead these buffers de-couple one line segment from another, and thus prevent downtime at one segment from shutting down downstream segments on account of no inventory. 1 Jamie Flinchbaugh is a Fellow in the Leaders for Manufacturing Program, Class of 1998, and is sponsored by Chrysler Corporation. This case is extracted from Implementing Lean Manufacturing Through Factory Design , an MIT Thesis by Jamie Flinchbaugh, 1998. 2 This case requires a working knowledge of the Toyota Production System. An adequate understanding can be reached by reviewing Harvard Business School case study Toyota Motor Manufacturing, U.S.A., Inc. (case number 9-693-019, September 5, 1995, prepared by Kazuhiro Mishina). 3 The andon process: each line worker can signal for help from the team leader if there is a quality problem. The team leader makes a decision on whether or not to stop the line, but if at all possible, will make sure that the quality problem is fixed before leaving the workstation. This results in problem solving closer to the problem and very little rework, resulting in a better quality product.
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
As far as managing the line, one group leader leads the team in each line segment. Under the group leader may be three or four team leaders who support teams of 6-10
Background image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 12/06/2011 for the course ESD 15.763j taught by Professor Davidsimchi-levi during the Spring '05 term at MIT.

Page1 / 4

design_lean_sysm - Massachusetts Institute of Technology...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online