Formula Sheet: RIveted and Welded Joint | Design of Machine Elements - Mechanical Engineering PDF Download

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Riveted, Bolted and Welded Joints -
Formula Sheet
1. Riveted Joints
(a) Tearing Strength of Plate
P
t
= (p- d)· t· s t
(b) Shearing Strength of Rivets
P
s
=n· p 4
· d
2
· t (c) Crushing Strength
P
c
=n· d· t· s c
(d) Efficiency of Joint
? =
Least of (P
t
,P
s
,P
c
)
p· t· s t
× 100%
Symbols:
• p: Pitch of rivet, d: Rivet diameter, t: Plate thickness
• n: Number of rivets in shear per pitch
• s t
, t , s c
: Allowable tensile, shear, and crushing stresses
2. Bolted Joints
(a) Axial Load (Preload + External)
F
b
=F
i
+C· P (Bolt load)
(b) Bolt Stiffness
k
b
=
A
b
E
b
l
b
(c) Joint Stiffness
k
j
=
A
j
E
j
l
j
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Riveted, Bolted and Welded Joints -
Formula Sheet
1. Riveted Joints
(a) Tearing Strength of Plate
P
t
= (p- d)· t· s t
(b) Shearing Strength of Rivets
P
s
=n· p 4
· d
2
· t (c) Crushing Strength
P
c
=n· d· t· s c
(d) Efficiency of Joint
? =
Least of (P
t
,P
s
,P
c
)
p· t· s t
× 100%
Symbols:
• p: Pitch of rivet, d: Rivet diameter, t: Plate thickness
• n: Number of rivets in shear per pitch
• s t
, t , s c
: Allowable tensile, shear, and crushing stresses
2. Bolted Joints
(a) Axial Load (Preload + External)
F
b
=F
i
+C· P (Bolt load)
(b) Bolt Stiffness
k
b
=
A
b
E
b
l
b
(c) Joint Stiffness
k
j
=
A
j
E
j
l
j
1
Riveted, Bolted & Welded Joints
(d) Load Shared by Bolt
C =
k
b
k
b
+k
j
(e) Torque to Tighten
T =K· F
i
· d
3. Welded Joints
(a) Throat Thickness (for fillet weld)
t =h· sin(45
? ) =
h
v
2
(b) Weld Strength under Axial Load
P =l· t· t (c) Bending Stress in Weld
t b
=
M· y
I
(d) Torsional Shear Stress in Weld
t t
=
T · r
J
(e) Resultant Weld Stress (Combined)
t res
=
q
t 2
d
+t 2
b
+t 2
t
Symbols:
• h: Leg length of weld, t: Throat thickness
• l: Weld length, t : Allowable shear stress
• M: Moment, T: Torque, I: Moment of inertia, J: Polar moment
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