Long Fillet Weld Subjected to Torsion
z
Try
T vertical plane
Torque acting
=
on
l
Length of weld
=
Size (or leg) of weld
E
-
Throat thickness
-
5 Polar moment of inertia (weld section)
H
=
J t t
S
2x
=
=
's T
6
V b
L
S
<
>
I -
Assumption: shearing stress due to torsion varies from zero (at Z axis) from maximum. (at end of plane)
W
I E TIPls-it
= =
4.242T
Imax 0.73x12
=
se2
=
Question : 1
A plate 1 m long, 60 mm thick is welded to another plate at right angles to each other by 15
mm fillet weld, as shown in figure. Find the maximum torque that the welded joint can sustain
if the permissible shear stress intensity in the welded material is not to exceed 80 MPa.
4.242T
Imax =
S2
80 =
4.242 x T
10002
15 x
T 15x80x106
=
4.242
T 282.9 =
100
x Nmm=282.9 kN.m
, Strength of butt joint
Assumption: Load resisting area is equal to the nominal cross section of thin welded parts, neglecting the size
of the reinforcement.
↑
Weld can achive 100% strength, but riveted joint can't achive full strength.
&
Butt joints are designed for tension or compression.
H
-
l
~
S
reinforcement
V
reinforcement v
-A
V
M
P t >P
W
>P
W
S PC 1
ta
V W
~
reinforcement
Single V butt
joint
Double Vbutt joint.
Throat thickness ( t ) = Weld size ( S ) = Plate thickness >butt joints
P tlCm for single V or P-applied force
square
=
t-throat I thickness
l- weld
length
P (t, t)l0 for double
= +
v
Ot-tensile strength
Size of the weld should be greater than the thickness of the plate, but it may be less.
Recommended minimum
size of the welds.
z
Try
T vertical plane
Torque acting
=
on
l
Length of weld
=
Size (or leg) of weld
E
-
Throat thickness
-
5 Polar moment of inertia (weld section)
H
=
J t t
S
2x
=
=
's T
6
V b
L
S
<
>
I -
Assumption: shearing stress due to torsion varies from zero (at Z axis) from maximum. (at end of plane)
W
I E TIPls-it
= =
4.242T
Imax 0.73x12
=
se2
=
Question : 1
A plate 1 m long, 60 mm thick is welded to another plate at right angles to each other by 15
mm fillet weld, as shown in figure. Find the maximum torque that the welded joint can sustain
if the permissible shear stress intensity in the welded material is not to exceed 80 MPa.
4.242T
Imax =
S2
80 =
4.242 x T
10002
15 x
T 15x80x106
=
4.242
T 282.9 =
100
x Nmm=282.9 kN.m
, Strength of butt joint
Assumption: Load resisting area is equal to the nominal cross section of thin welded parts, neglecting the size
of the reinforcement.
↑
Weld can achive 100% strength, but riveted joint can't achive full strength.
&
Butt joints are designed for tension or compression.
H
-
l
~
S
reinforcement
V
reinforcement v
-A
V
M
P t >P
W
>P
W
S PC 1
ta
V W
~
reinforcement
Single V butt
joint
Double Vbutt joint.
Throat thickness ( t ) = Weld size ( S ) = Plate thickness >butt joints
P tlCm for single V or P-applied force
square
=
t-throat I thickness
l- weld
length
P (t, t)l0 for double
= +
v
Ot-tensile strength
Size of the weld should be greater than the thickness of the plate, but it may be less.
Recommended minimum
size of the welds.
