This website requires certain cookies to work and uses other cookies to help you have the best experience. By visiting this website, certain cookies have already been set, which you may delete and block. By closing this message or continuing to use our site, you agree to the use of cookies. Visit our updated privacy and cookie policy to learn more.
This Website Uses Cookies
By closing this message or continuing to use our site, you agree to our cookie policy. Learn More
This website requires certain cookies to work and uses other cookies to help you have the best experience. By visiting this website, certain cookies have already been set, which you may delete and block. By closing this message or continuing to use our site, you agree to the use of cookies. Visit our updated privacy and cookie policy to learn more.
Quality Magazine logo
search
cart
facebook twitter linkedin youtube
  • Sign In
  • Create Account
  • Sign Out
  • My Account
Quality Magazine logo
  • Home
  • The Magazine
    • Current Issue
    • Digital Edition
    • Archives
    • How To Guide
    • Industry News
    • Subscribe
  • Web Exclusives
    • Blogs
    • NDT Exclusives
    • Quality Exclusives
    • Vision & Sensors
  • New Products
  • Channels
    • Management
    • Measurement
    • NDT
    • Quality 101
    • Software
    • Test & Inspection
    • Vision & Sensors
  • Markets
    • Aerospace
    • Automotive
    • Electronics
    • Energy
    • Green Manufacturing
    • Medical
    • Plastics
  • More
    • Leadership 100 Survey
    • Plant of the Year
    • Professional of the Year
    • Job Board
    • White Papers
    • Quality Store
    • Software Downloads
    • eCards
    • Product Spotlights
    • Industry Links
    • Sponsor Insights
    • Market Research
  • Multimedia
    • eNewsletter
    • Podcasts
    • Videos
    • Webinars
    • Showcases
    • Image Galleries
    • Interactive Spotlights
  • Events
    • IMTS
    • Event Calendar
    • Quality Show
  • InfoCenters
    • Manage Quality, Risk & Compliance
    • Material Science Quality within Microscopy
    • Modern Quality Control with SPC
    • Process Control in Manufacturing
  • Directories
    • Buyers Guide
    • NDT Sourcebook
    • V&S Sourcebook
    • Take a Tour
  • Contact
    • Contact Us
    • Advertise
Home » Brain Teasers: Collapsing Tents

Brain Teasers: Collapsing Tents

February 1, 2005
Dr. Sophronia Ward
Reprints
2 Comments
Anyone who has faced a production problem with a need to solve it by using production data can relate to the notion of a brain teaser. The brain teasers presented here are based on real-world situations that are encountered by workers in manufacturing environments. The brain teasers have three parts: (1) the situation, (2) available data or other supporting information and (3) questions that various workers want answered for continual improvement. Recommended solutions follow in the next issue and on the Web at Quality Online (www.qualitymag.com).

Situation

For 12 years, Travis worked in production for a company that makes camping equipment for recreation purposes. He recently was transferred back to production from a special assignment on an ISO initiative. Because his background is in engineering, he was assigned the responsibility of monitoring both the specifications of all components and the final product for the two production lines that make collapsible tents. These two production lines are exact replicas of each other.

Production Line 1 appears to be running smoothly, but Production Line 2 has had trouble with the final assembly of the internal frames for these tents. Travis decided to start by checking to see how the lengths of frame sections made on each production line compared to specifications. The desired Cpk is 1.33.



Available data

Travis obtained data collected by the quality control (QC) inspectors for each production line at the point where the frame sections are transferred to assembly. Data for frame section lengths are collected twice each shift with a subgroup size of 4. The data for both production lines are shown in the table, "Lengths of Tent Frame Sections." An initial glance at the data values indicates that all tent frame sections meet the specifications for length. One QC inspector told Travis that production Line 1 has a Cpk less than 1, while production Line 2 has a Cpk that is closer to the desired value.



Questions

Is Travis correct in stating that the tent frame sections from both production lines meet specification for length?

What is the behavior of each production line for the length of the tent frame sections?

Which production line is doing a better job of meeting specifications?

Why is production Line 2 having trouble with assembly?



Answers to January Brain Teaser

In her capacity as a chemist for a company that makes rubber products, Cameron is responsible for all batches of rubber meeting specifications. Recently, she learned that even when the rubber meets the current specifications for flash, a characteristic that is connected with the curing of the rubber, the rubber may not cure correctly. Production requires that specifications be much tighter than the ones currently in use.

Q: Are all of the flash values for the 30 batches of rubber meeting the original specifications of 12±3?

A: From a histogram, it is easy to see that all of the batches meet the original specifications of 12±3 for the flash values.

Q: Is the process for making batches of rubber predictable with respect to the flash values?

A: The process is not predictable for flash values. The individuals and moving range chart, "Flash Values for Batches of Rubber," shows two long runs of eight or more values. This indicates that the process suffers from changes that are sustained but not severe enough to cause flash to be outside the current specification.

Q: What in the data should raise questions concerning the rubber batches?

A: These sustained changes that make the batches of rubber lower or higher on the average may be associated with the trouble the production line is having in curing. Getting the process to be predictable is the first step toward determining exactly what specifications are required by production for proper curing.

Q: What can Cameron do with the insights from this analysis?

A: Cameron can show both the people making batches of rubber and those working in production the impact of the unpredictable behavior of the flash values.

subscribe to Quality Magazine

Recent Articles by Sophronia Ward

Brain Teasers: Improvement Challenges

Brain Teasers: Can You Solve the Final Brain Teaser?

Brain Teasers: Leaky Valves

Brain Teasers: First Pass Yield Confusion

Brain Teasers: Cpk for a Predictable Process

Dr. Sophronia Ward is a continual improvement specialist and Six Sigma Senior Master Black Belt and Coach. Brain teasers are now incorporated in the new training programs, Six Sigma Training for Champions, Black Belts and Green Belts, offered by Dr. Ward and her associates at Pinnacle Partners Inc. For more information, call (865) 482-1362 or visit www.pinnaclepartnersinc.com.

Related Articles

Brain Teasers: A Manager's Challenge: Investigating Cause

Brain Teasers: A Chilling Process

Quality Brain Teasers

Brain Teasers: The Same, But Different

You must login or register in order to post a comment.

Report Abusive Comment

Subscribe For Free!
  • Print & Digital Edition Subscriptions
  • eNewsletters
  • Online Registration
  • Subscription Customer Service
  • Mobile Help

More Videos

Popular Stories

Lean manufacturing

Lean In to 5S

Automation in manufacturing

Automated Metrology: Manufacturing Trend of the Future

ASNT

ASNT Annual Conference Brings NDT to Las Vegas

RoyalPower

Royal Power Solutions Opens Innovation Center

EdmundsED

Edmund Optics Announces 2019 Educational Award, Norman Edmund Award Recipients

Quality Leadership 100 Survey

Poll

Topics to Talk About

What topics would you like to see Quality cover more?
View Results Poll Archive

Products

Quality Brain Teasers: Real World Challenges to Build Your Manufacturing Skills (ebook)

Quality Brain Teasers: Real World Challenges to Build Your Manufacturing Skills (ebook)

Assessments and Training in the following areas...

See More Products

SoftwareDownloads

Quality Magazine

Quality December 2019

2019 December

Check out the December 2019 edition of Quality: Quality 4.0 for medical device manufacturing, automated metrology, gage trends, plastics, materials analysis and much more!
View More Create Account
  • Resources
    • Market Research
    • Custom Content & Marketing Services
    • List Rental
    • Partners
    • Manufacturing Group
    • Polls
    • Privacy Policy
    • Survey and Sample
  • Want More
    • Connect

Copyright ©2019. All Rights Reserved BNP Media.

Design, CMS, Hosting & Web Development :: ePublishing