Rechnerischer Festigkeitsnachweis für Maschinenbauteile - 7. Auflage 2020 | Print

7th edition 2020
232 pages
This 7th edition of the FKM guideline "Calculated strength verification for machine components" has been completely revised, making it impossible to list all the changes.
The following significant changes have been made to the calculation algorithm:
- ductility was defined with reference to the elongation at break,
- the long-term temperature factors were reformulated,
- for the calculation of the plastic support number, the recoverable reference elongation was increased by the elastic component and the hardening factor was introduced,
- the static strength values of welded aluminum components were formulated with reference to Eurocode 9,
- the stress definition in the fatigue strength verification was extended so that the critical section plane method can always be used,
- the amplitude and equivalent stress verifications were formally presented as equivalent,
- the parameters for the support number calculation according to Siebel & Stieler for cast aluminum were adjusted,
- the applicability of the protective coating factor was extended to galvanized steel,
- formulated the limitation of the maximum amplitude taking into account the mean stress,
- added notes on the Wöhler line system,
- reformulated the sign rule for the comparative load,
- added a clarification of the decisive load factor in the fatigue strength verification,
- completely revised the material tables,
- the material group "Ausferritic cast iron with nodular graphite" (ADI) was added,
- the section with notch coefficients for shafts with hub seats was brought closer to DIN 743,
- the fatigue strength verification for welded components was reformulated on the basis of notch and effective stresses and
- special surface layer factors for post-weld treatment were specified.
The description of overload cases F3 and F4 has been removed due to their relatively rare practical use. However, their use in the sense of the earlier editions of the FKM Guideline is still permissible.

Contents

0 General
0.1 Scope
0.2 Fundamentals
0.3 Required verifications
0.4 Stresses and component types
0.5 Calculation procedure
1 Static strength verification with nominal stresses
1.0 General
1.1 Stress parameters
1.2 Material parameters
1.3 Design parameters
1.4 Component strength
1.5 Safety factors
1.6 Verification
2 Fatigue strength verification with nominal stresses
2.0 General
2.1 Characteristic stress values
2.2 Characteristic material values
2.3 Characteristic design values
2.4 Component strength
2.5 Safety factors
2.6 Verification
3 Structural strength verification with local stresses
3.0 General
3.1 Characteristic stress values
3.2 Characteristic material values
3.3 Characteristic design values
3.4 Component strength
3.5 Safety factors
3.6 Verification
4 Fatigue strength verification with local stresses
4.0 General
4.1 Characteristic stress values
4.2 Characteristic material values
4.3 Characteristic design values
4.4 Component strength
4.5 Safety factors
4.6 Verification
5 Appendices
5.1 Material tables
5.2 Form numbers
5.3 Notch effect numbers
5.4 Component classes for welded components made of structural steel and aluminum alloys
5.5 Estimation of the fatigue strength of surface-strengthened components
5.6 Experimental determination of component strength values
5.7 Load assumptions
6 Examples
6.1 Shaft shoulder
6.2 Cast component
6.3 Compressor flange made of gray cast iron
6.4 Welded perforated bar
6.5 Welded T-section made of aluminum
6.6 Welded aluminum construction
7 Formula symbols
7.1 Abbreviations
7.2 Indexes
7.3 Lower-case letters
7.4 Upper-case letters
7.5 Greek letters
7.6 Underlying formulas
8 Changes