Reliability prediction using Stress Strength Interference (Analytical Method)

Dear friends,
Often, products fail, and we don’t understand why! One of the reasons why such failures occur is not giving consideration for variation in load or stress levels. For example, potholes and speed breakers can create excessive stress on automobile suspensions; or larger number of clothes washed in a machine more often than the designer has considered; or a bus used in public transport would carry varying number of passengers! Designers often do not realize that the materials used in the product will also have variations! For example, wall thicknesses of castings will vary; or chemical composition of steel will vary from lot to lot! Thus, designers need to address the variations in usage patterns and variations in the materials used in the product as these can seriously affect reliability of systems! In my recently uploaded video, I have discussed how to predict reliability when load (stress) and strength of the part both vary and can be modelled using normal distribution. The video will also be very useful to those who wish to take ASQ Certified Reliability Engineer exam and all those who wish to learn the basics of reliability in design. This is the first video where the stress and strength can be modelled using normal distribution. In the next video related to this topic, I will explain reliability prediction using Monte Carlo Simulation.

[@anilbp]

Thank you!

[@instituteofqualityandrelia7902]

You're welcome!

[@AyaSayed--]

Thanks dr.Hemant

[@instituteofqualityandrelia7902]

So nice of you! Welcome!

[@pankajkumar-jo5sp]

Good explanation

[@instituteofqualityandrelia7902]

Thanks a lot!

[@kinphoon2910]

Do you have the link for your next video to show how to calculate the reliability with Monte Carlo simulation?thanks

[@instituteofqualityandrelia7902]

Sure! Here is the link: czcams.com/video/-G5DSzPIEjU/video.html.

[@ArunKumar-eu4sc]

Thank you, in reality . how to calculate the standard deviation of the specimen?. When testing is not practical

[@instituteofqualityandrelia7902]

Thanks Ankur! The standard deviation can be estimated using historical data. If you cannot test, then you may refer to handbooks. FOr example, there may be material standard that specifies tolerance. You may need to make an assumption that SD is 1/6th of the tolerance. This of course is approximate and can be used for guidance.