ASQ

Exclusive Content & Downloads from ASQ

An Economic Study of X-Bar Charts with Warning Limits

Summary: This paper investigates the economic design of x-bar charts with both warning and action limits, based on a widely studied process model. The optimization is accomplished by a three-dimensional pattern search. Various comparisons are made among the minimum cost designs of x-bar charts with and without warning limits and of Cusum charts. No appreciable differences are found. X-bar charts with warning limits are thus recommended for practical application as they are much easier to handle than Cusum charts, and they provide more psychological protection than x-bar charts with action limits only. It is proposed that in application the band enclosed by the warning limits should be 0.85 times as wide as the band enclosed by the action limits. A simplified economic scheme for the design of control parameter values is also suggested.

Anyone with a subscription, including Site and Enterprise members, can access this article.


Other Ways to Access content:

Join ASQ

Join ASQ as a Full member. Enjoy all the ASQ member benefits including access to many online articles.

Subscribe to Journal of Quality Technology

Access this and ALL OTHER Journal of Quality Technology online articles. You'll also receive the print version by mail.

  • Topics:
  • Keywords: Cumulative sum control chart (CUSUM),Economic design,X-bar control charts,Warning limits
  • Author: Chiu, W.K.; Cheung, K.C.
  • Journal: Journal of Quality Technology