Your Reliability Engineering Professional Development Site
A listing in reverse chronological order of articles by:
As with other programs, an RCA program needs to be driven from the top and supported through all levels of the organization. This includes upper management, supervision or mid-management, and those on the front line doing the [Read more…]
In my prior article, an overview of vehicle telematics was provided. Telematics data includes time stamped records and fields containing count or parametric data recorded from the vehicle CAN bus. The count data is always a non-negative integer and the parametric data is stored as real numbers, generally in scientific format. This article focuses on the analysis of counting data.
Count data is used to monitor events, i.e., the number of trips, the days of operation, the calendar date, door open/close cycles, the number of engine starts/stops, or other variables. So, if a variable is selected for analysis, how can it be analyzed and a vehicle be characterized? How can fleets be analyzed? Can vehicle usage percentiles be determined?
[Read more…]
This is the first in a nine-part series of articles. This first one will lay out what I think are essential characteristics of an RCA program. The other articles will follow up on each of the items in some detail.
Have you ever felt overwhelmed with too much to do? I imagine most of us have struggled with time management at one time or another. There are just too many things on our plate, and they never go away.
Some may attribute this burden to their life, or perhaps they are inefficient time managers, or something else. Regardless, I doubt many enjoy the feeling or the situation.
If only we could walk across the bridge to self improvement and be enlightened.
Product design, development, and reliability engineers need to verify that their product meets specifications, which include dimensional requirements, functional definitions, and life testing. How are the requirements validated?
Telematics data is collected to show how a vehicle has been operated. Fleets and retail data are stored on servers for engineering analysis. This data can be used to set new requirements or validate older requirements.
In my last article, RCA Templates Use or not?, I discussed templates and suggested that while beneficial for many things, they may not provide as much value for those doing RCA’s. This is because for any specific effect, the variability in the cause tree is significant and difficult to predict. This doesn’t mean that there are no options to utilize templates to help speed up the process, but perhaps not in the way that people might be used to. [Read more…]
What is a template? Merriam-Webster has two definitions that seem to apply to RCA work. They are: 1) a gauge, pattern, or mold (such as a thin plate or board) used as a guide to the form of a piece being made; 2) something that establishes or serves as a pattern. For our discussion let’s use the second. [Read more…]
Here is a diagram I generated when I was in the reliability group at my facility.
It came about because I was trying to identify why we may not be showing the value that was expected from the reliability improvement work we were doing. [Read more…]
The goal of a reliability initiative is to save money, not to “install” a system.
If that is not your current goal, then how did it get changed? Change sometimes happens slowly, so slowly that we don’t notice it.
I’m reminded of a fable about a camel and a Bedouin. It is cold outside and the [Read more…]
Reliability initiatives are implemented to improve a company’s bottom line, period.
Root cause analysis is one of the fastest ways I know to achieve this improvement. My boss used to say “show me the money” because he realized that upper management was driven by ROI (Return on Investment) or ROC (Return on Capital).
You can argue all you want on whether that is good or bad, but it is the way things are. [Read more…]
Recently there was a power outage, that caused approximately 2,000 homes to lose power during a very cold day. The paper headline read, “All-day outage caused by worn wiring”.
This seems like a reasonable comment and probably like many other newspaper headlines also seems to go a long way to explain what caused the 2,000 homes and business to lose power for 5 ½ hours, and the 300 that lost power for a total of 11 ½ hours. [Read more…]
Occasionally, I like to step back and reflect on reliability in basic terms.
In that spirit, the basic premise of reliability is usually stated as “The probability that an item will perform a required function, without failure, under stated conditions, for a stated period of time.”
To use the reliability equation, the definition of failure must be defined, so you can tell if your equipment has indeed failed. This way you can include it in the MTBF (Mean Time Between Failure) calculation.
After you have defined a failure and recorded them appropriately, you can plug the numbers into the reliability equation, R = e ^-(λ*t) where λ is the failure rate which is defined as λ= 1/MTBF and come up with an objective value for the reliability. [Read more…]