SENG 312 EXAM 3 STUDY GUIDE
Failure Modes and Effects Analysis - Answer -FMEA stands for this
Questions for FM of FMEA - Answer -What could go wrong? and how?
Questions for E of FMEA - Answer -What are the consequences?
Questions for A of FMEA - Answer -Probability of occurrences and severity of the
consequences
Failure - Answer -Departure of an item from its required or intended operation, function
or behavior.
The inability of a system, subsystem, or component to perform its required function.
The inability of an item to perform within previously prescribed limits
Failure Mode - Answer -Manner by which an item fails; the mode or state the items is in
after it fails. The way in which the failure of an item occurs
What is FMEA used for? - Answer -An equipment oriented tool for finding potential
failure modes of subsystems, assemblies, components, or functions.
What questions does does FMEA answer? - Answer -What can fail?
How does it fail?
How frequently will it fail?
What are the effects of the failure?
What is the reliability/safety consequences of the failure?
What are the column titles of the FMEA worksheet? - Answer -Item
Identification
Description
Failure Modes
Effects
Safeguards
Actions
Typical general failure modes - Answer -Failure to operate
premature operation
intermittent operation
failure to cease operation at prescribed time
Loss of output
Degraded output
Example Failure Modes for Switch - Answer -open, partially open, closed, partially
closed, chatter
, Example Failure Modes for Valve - Answer -Open, partially open, closed, partially
closed, wobble
Example Failure Modes for Spring - Answer -Stretch, compress/collapse, fracture
Example Failure Modes for Cable - Answer -Stretch, break, kink, fray
Types of FMEA - Answer -Concept FMEA, Design FMEA, Process FMEA
Design FMEA - Answer -analyze product design before release to production, with a
focus on product function (early concept and design stages)
Process FMEA - Answer --used to analyze manufacturing and assembly processes
after they are implemented
-identify potential product related process failure modes
-assess the potential customer effects of the failures
-identify the potential manufacturing causes
Background info needed for Design FMEA - Answer --Detail Design
-Component list
-Functions of components
-Operating conditions
-Design Specifications
-Details of operating methods
-Critical parameters of design
Background task for process FMEA - Answer --Details of manufacturing
process/process flow chart
-list of critical process parameters (temp, P)
-properties of device material
-manufacturing environment details
-manufacturing tool details
-batch to batch variation
Failure modes, effects, and criticality analysis - Answer -FMECA stands for this. Its
FMEA plus an evaluation of how critical a component is to system success
How are components ranked in FMECA? - Answer -based on Failure mode criticality
number Cm
Failure mode ratio - Answer -alpha in the criticality number:
probability that the component will fail in the identified mode
Failure Modes and Effects Analysis - Answer -FMEA stands for this
Questions for FM of FMEA - Answer -What could go wrong? and how?
Questions for E of FMEA - Answer -What are the consequences?
Questions for A of FMEA - Answer -Probability of occurrences and severity of the
consequences
Failure - Answer -Departure of an item from its required or intended operation, function
or behavior.
The inability of a system, subsystem, or component to perform its required function.
The inability of an item to perform within previously prescribed limits
Failure Mode - Answer -Manner by which an item fails; the mode or state the items is in
after it fails. The way in which the failure of an item occurs
What is FMEA used for? - Answer -An equipment oriented tool for finding potential
failure modes of subsystems, assemblies, components, or functions.
What questions does does FMEA answer? - Answer -What can fail?
How does it fail?
How frequently will it fail?
What are the effects of the failure?
What is the reliability/safety consequences of the failure?
What are the column titles of the FMEA worksheet? - Answer -Item
Identification
Description
Failure Modes
Effects
Safeguards
Actions
Typical general failure modes - Answer -Failure to operate
premature operation
intermittent operation
failure to cease operation at prescribed time
Loss of output
Degraded output
Example Failure Modes for Switch - Answer -open, partially open, closed, partially
closed, chatter
, Example Failure Modes for Valve - Answer -Open, partially open, closed, partially
closed, wobble
Example Failure Modes for Spring - Answer -Stretch, compress/collapse, fracture
Example Failure Modes for Cable - Answer -Stretch, break, kink, fray
Types of FMEA - Answer -Concept FMEA, Design FMEA, Process FMEA
Design FMEA - Answer -analyze product design before release to production, with a
focus on product function (early concept and design stages)
Process FMEA - Answer --used to analyze manufacturing and assembly processes
after they are implemented
-identify potential product related process failure modes
-assess the potential customer effects of the failures
-identify the potential manufacturing causes
Background info needed for Design FMEA - Answer --Detail Design
-Component list
-Functions of components
-Operating conditions
-Design Specifications
-Details of operating methods
-Critical parameters of design
Background task for process FMEA - Answer --Details of manufacturing
process/process flow chart
-list of critical process parameters (temp, P)
-properties of device material
-manufacturing environment details
-manufacturing tool details
-batch to batch variation
Failure modes, effects, and criticality analysis - Answer -FMECA stands for this. Its
FMEA plus an evaluation of how critical a component is to system success
How are components ranked in FMECA? - Answer -based on Failure mode criticality
number Cm
Failure mode ratio - Answer -alpha in the criticality number:
probability that the component will fail in the identified mode
