Edge distance of the opening point

Symbol	u
Unit	mm
Attribute-ID	vdi_2230_edge_distance_of_the_opening_point
Numeric ID	12114
Value Type	PMTechValue

The edge distance u of the opening point U from the axis of the imaginary laterally symmetrical deformation solid 0 is required to design the bolted joint in such a way that opening is prevented.

0	Axis of the imaginary laterally symmetrical deformation solid
S	Bolt axis
F_S	Bolt load
F_A	Axial load
a	Distance of the axial force from the axis of the imaginary laterally symmetrical deformation solid
s_sym	Distance of the bolt axis from the axis of the imaginary laterally symmetrical deformation solid
u	Edge distance of the opening point U from 0
U	Opening point
v	Distance of the edge bearing point V from 0
V	Edge bearing point

Loading case/ variant		Tensile working load			Compressive working load
		I	II	III	IV	V	VI
Dimensional ratios		position of a and s_sym at 0			position of a and s_sym at 0
		on same side		different sides	on same side		different sides
		a≥s_sym	a<s_sym		a≥s_sym	a<s_sym
Sign	s_sym	+	+	-	+	+	-
	u	+	-	+	-	-	-
Explanations		The distance a of the substitutional line of action of the axial working load is always positive. Point U always lies at the outermost location of that side of the interface which is at risk of opening, and consequently point V lies at the outermost location of the other side. The distance v is always positive.

Note: Cases V and VI can only lead to opening in exceptional instances. Case IV is only illustrated for the sake of completeness; opening cannot be expected.

Table from: VDI 2230 Part1, VDI Verlag Düsseldorf, 2015, p. 69, "Table 4. Sign rules"