Shigley’s Mechanical Engineering Design, 8
Class Notes by:
Dr. Ala Hijazi
Page 1 of 16
CH 1: Introduction
what is; Engineering creates
what never was.
System, Input, Output
Input, Output, Laws
System, Input, Laws
System, Output, Laws
The designed product must be
functional, safe, reliable, usable, competitive,
manufacturable, and marketable.
Codes and Standards
Codes and standards are made to organize and unify
the engineering work.
Imagine; what if there was no standard for bolts?
is a set of specifications for the analysis, design, manufacture, and
construction of something.
is a set of specifications for parts, materials, or processes intended to
achieve uniformity, efficiency and specific quality.
Examples of organizations that established standards and design codes: AISI, AGMA,
SAE, ASTM, ISO.
Stress and Strength
When designing a component, the designer need to make sure that the maximum
stress is less than the strength of the material used for making that component.
) depends on geometry
) is a material property
; strength is the stress level at which
something occurs (such as yield strength or ultimate strength).
Laws of nature