Design of Outfit Elements in Ships for Fatigue Technical ... - EWF

Page 2 of DVS 3501
Comments
Description of Type of connection Detail
category
∆σR Equipment Detail Sketch of connection with
fatigue crack and stress
considered σ
Stress concentrations caused by the
opening to be considered as follows
140
(m0 = 4)
Plate edges punched or machine-cut by means of a thermal
cutting process. The cutting surface is free of cracks and
notches. Cutting edges are chamfered or rounded
1.1 Openings uniaxially loaded
∆σmax = K1 ⋅ ∆σN bzw. ∆σRperm ≤ ∆σR /K t
K t: Notch factor according to GL Section 3
∆σN: Nominal stress range related to net
section
alternatively direct determination of ∆σmax from FE-calculation, especially in case of
multiple arrangement of openings
Plate edges which are not meeting the above mentioned
requirements, but are free from cracks and sharp notches
125
(m0 = 3.5)
Machine cut or punched:
or σ x >> σ y
100
(m0 = 3.5)
Manually cut:
Stress concentrations caused by the
opening to be considered as follows
140
(m0 = 4)
Plate edges punched or machine-cut by means of a thermal
cutting process. The cutting surface is free of cracks and
notches. Cutting edges are chamferred or rounded
1.2 Openings biaxially loaded
∆σmax = K1 ⋅ ∆σN K t: Notch factor according to Fig. 2
∆σN : Nominal stress range related to net
section
alternatively direct determination of ∆σmax from FE-calculation, especially in case of
multiple arrangement of openings
Plate edges which are not meeting the above mentioned
requirements, but are free from cracks and sharp notches
125
(m0 = 3.5)
Machine cut or punched:
100
(m0 = 3.5)
Manually cut:
σ x ≈ σ y
Stress concentrations caused by the
opening to be considered as follows
140
(m0 = 4)
1.3 Openings shear-loaded Plate edges punched or machine-cut by means of a thermal
cutting process. The cutting surface is free of cracks and
notches. Cutting edges are chamferred or rounded
∆σmax = K1 ⋅ ∆σN K t: Notch factor according to Fig. 3
∆σN : Nominal stress range related to net
section
alternatively direct determination of ∆σmax from FE-calculation, especially in case of
multiple arrangement of openings
Plate edges which are not meeting the above mentioned
requirements, but are free from cracks and sharp notches
125
(m0 = 3.5)
Machine cut or punched:
100
(m0 = 3.5)
Manually cut: