Design Reliability Flashcards
What is Reliability?
It is a characteristic that describes how good a product is.
It is defined as the probability that an item will perform its intended function for a given time period, under a given set of operating conditions.
The probability that a product will still be functioning at time t.
What is Unreliability?
A measure of the potential for failure of a device.
Leads to high cost of repair or replacement, re-design, poor reputation, and maybe injury or death.
What is Failure?
It is the degradation of the performance of a device or process outside of a specified value.
What is a defect?
An imperfection
What is a deficiency?
A lack of conformance to specifications
What is a fault?
Cause of failure
What is a malfunction?
Unsatisfactory performance
What does MTTF stand for?
Mean Time To Failure
What does MTTR stand for?
Mean Time To Recover/Repair
What does MTBF stand for?
Mean Time Between Failures
What does FR stand for?
Failure Rate.
It is defined as the Number of Failures per number of unit-hours of operation
What is series system reliability?
Each component connected in series has a reliability of R. If one component fails, the entire system fails.
What is parallel system reliability?
Each component in parallel has a reliability R. If one component fails, the system can still function, however if both fail, the system fails.
