forging new generations of engineers. factors of design and safety
Post on 18-Jan-2016
212 Views
Preview:
TRANSCRIPT
Forging new generations of engineers
Factors of Design and Safety
Factors in Design
Complexity of stress analysis
Consequences of failure
Environmental exposure
Material Strength
Potential Misuse of the Product
Factors in Design (continued)
Quality Control
Size or Mass Effect
Stress Concentration Factors
Types of Loads
Type of Material
Cost
Factor of Safety
• Used by engineers to account for uncertainty in applied forces, material properties, model assumptions, etc.
• The allowable stress in the part is determined by the following formula.
• An acceptable design is when the calculated stresses in the part are less than the allowable stress.
Allowable Stress = Material Strength Factor of Safety
Factor of Safety
Multiplier for Factor of Safety
Ductile Materials Brittle Materials
Type of load Yield Strength
Ultimate Strength
Ultimate Strength
Static 2 - 6
Repeated - 8 10
Impact - 12 15
top related