Chapter 8: Managing Quality Learning Activity: How Available are my Machines??? Using the data collected over the past 2 years, compute the average Availability of this Baseball Stitching Machine. (Insert formulas in the yellow cells and answer the question below.) Availability defines the continuity of usability to the customer. Availability results from your ability to create high Reliability, fast Maintainability (when machines do break) and good Logistical support (parts are on-hand or quickly acquired). Here's this important combination: Time between Time to make last breakdown last repair (hours) (hours) Date of Failure Stitching Machines Reliability Availability Maintainability June 10, 2019 Machine #1 225 3 MTBF = hours Logistical support Reliability refers to the length of time a product can be used before it fails. Reliability is measured as mean time between failure (MTBF), which is the average time the product functions from one failure to the next. April 17, 2020 Machine #2 289 3 Mean Time Between Failure = MTBF May 27, 2020 Machine #3 212 10 MTTR = hours Maintainability refers to the restoration of a product or service once it has failed. All customers consider maintenance or repairs a nuisance. Thus, a high degree of maintainability is desired so that a product can be restored to use quickly. Maintainability can be measured by the mean time to repair (MTTR) the product. July 10, 2020 Machine #1 396 8 Mean Time To Repair = MTTR August 29, 2020 Machine #2 134 10 Availability = A product is available if it is in an operational state and not down for repairs or maintenance. Availability can be measured quantitatively as follows: October 13, 2020 Machine #3 139 7 November 27, 2020 Machine #2 90 4 Do you see anything going on here that need management's attention? MTBF Availability = Uptime Uptime + Downtime MTBF + MTTR January 18, 2021 ne #3 97 8