kisssoft-anl-003-E-din743-intro
kisssoft
KISSsoft, shaft analysis:
Introduction to DIN 743, October 2000
Shafts and axles, calculation of load capacity
Introduction
Purpose
Introduction to DIN 743 The DIN 743 for strength analysis of shafts and axles is a most helpful analysis method available in the KISSsoft software, [1], for analysis of machine elements. The standard however is available in German only and the theory behind the software KISSsoft is not readily available for non german speaking customers. Therefore, a short introduction to the said standard is given herewith. The DIN 743 The German standard DIN 743 [2] has been prepared by the German institute for standardisation and the Institut für Maschinenelemente und Maschinenkonstruktion of the technical university of Dresden, Germany. The objective was to make available for the engineering community a standard focusing on strength analysis of shafts and axles. The standard is based on the standard TGL 19340 of the former German Democratic Republic, the VDI 2226 of the Federal Republic of Germany and the FKM
guideline compiled by the IMA Dresden, Germany, see [3], [4], [13]. The proof of strength is based on the calculation of a safety factor against fatigue and against static failure. The safety factors have to be higher than a required minimal safety factor. If this condition is fulfilled, proof is delivered. The standard consists of four parts:
Part 1: Introduction, analysis method
Part 2: Stress concentration factors and fatigue notch factors
Part 3: Materials data
Part 4: Examples
Limitations
The analytical proof considers bending, tensile/compressive and shear stresses due to torsion.
However, shear stresses due to shear forces are not considered, hence use of this standard for short shafts requires caution.
Only the fatigue limit is used in the proof, no proof for finite life strength is delivered. However, an extension is planned, see section 0.
Materials data are based on 107 stress cycles with a probability of survival of 97.5%.
The safety factor required in the standard covers only the uncertainty in the analysis procedure.
Additional safety factors or an increased safety factor due to uncertainties in the load assumptions and due to the effects of a failure are not defined. They have to be defined by the engineer.