Basic Rules of Engineering Design

1
Basic Rules of Engineering Design

• Safe
• Simple
• Clear

2
Interrelationship Between the Safety Levels
3
Definition Safety

• Safety
• is a state in which the risk is smaller than the
  risk limit
• Risk limit
• is the largest still acceptable system-specific
  risk relating to a particular technical process
  or situation
• Protection
• is the reduction of risk by suitable means to
  reduce the frequency of the occurrence or the
  extent of damage or both

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Safety Aspects of a System
5
Aspects of Safety Technology

• Self-protection product liability
• EC machinery directive DIN EN 292 VDE 100 VDI
  2244
• CE-Certification declaration of conformity
• ISO 9001 document management modification
  management version management

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Aspects of Safety Technology

• Market acceptance
• safe and environment-friendly products are
  received better by the market
• customers are prepared to pay more for safer
  products
• safety leads to a positive brand image Mercedes,
  Volvo, Saab.

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Safe Embodiment Design
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Direct Safety Principles
9
Safe-Life

• Important Measures
• Over-dimensioning of parts
• Clear and simple embodiment design
• Field-tests for determining the actual loads
• Employ experienced interdisciplinary teams for
  the development
• Documented quality assurance over the complete
  life-cycle
• Inspection/maintenance

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Example Fail-Safe
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Redundancy Principle
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Indirect Safety Principles
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Control of a Safety Fence
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Aspects of Warning Safety Technology

• Lowest level of safety technology supplementary
  to other measures
• minimum measure when no other safety principle is
  applicable
• consider aspects of noticability and ergonomics

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Warnings
16
Aspects Concerning Safety Data Sheets

• safety data sheets describe the danger potential
  of materials and substances
• the danger potential of materials and substances
  must be considered over the complete life cycle
  of a product
• - production
• - commissioning
• - operation
• safety data sheets are a part of the product
  documentation

17
Material Aspect of Safety Technology

• The safety of a product can be increased by
  choosing a material that suits the operating
  conditions of the product
• Determining the operating conditions is crucial
  for the choice of materials
• - corrosion resistant materials
• - fatigue resistant materials
• - materials that have a good adhesion to
• lubricants

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Selecting Material Designed for Safety
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The Nature of Principles of Embodiment Design
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Aim of Principles of Embodiment Design

• The application of principles of embodi-ment
  design leads to products that are optimally
  designed regarding the requirements taken into
  account!

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Direct and Short Force Transmission Path
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Direct and Short Force Transmission
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Direct and short force transmission
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Direct and Short Force Transmission

• Flowlines of force must always be closed
• Force transmission must be as short as possible
• Avoid
• deflection of forces
• discontinuous change of cross-section
• change of density of force flowlines

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Direct and short force transmission
Idea of force transmission DefinitionThe basic
idea and illustration of force and moment
transmission is taken from the field of fluid
mechanicsSource
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Direct and short force transmission

• Fundamentals
• The flowlines of force should always be closed.
  (Inertial forces are not taken in to
  consideration)
• The stresses and strains change with in circular
  flowlinesof force.
• The flowlinesof force searches the shortest path
• The flowlinesof force come closer in narrow cross
  sectional areas.-On the other hand, they expand
  in broad cross sectional areas

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Direct, Short Force Transmission Welding
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Direct Force Transmission Bearing Pedestal
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Direct Force Transmission Relief Notches
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Matched DeformationShaft-Hub Connection
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• Principle of Balanced Forces
• Target
• Reached by system is free of forces to the
  outside
• symmetric structure of the system regarding the
  flow of forces