- Fundamentals of design
- Design of joints, levers and offset links
- Design of shafts, keys and couplings
- Design of power screws
- Design of springs
- Design of bolted and welded joints
- Selection of anti-friction bearings and gears
Design of Bolted and Welded joints
1 Setscrews are- (A) Similar to tap bolts except that a greater variety of shapes of heads are available
- (B) Slotted for screw driver and generally used with a nut
- (C) Used to prevent relative motion between parts
- (D) Similar to studs
2 The designation M 36 x 2 means
- (A) Metric threads of 36 mm outside diameter and 2 mm pitch
- (B) Metric coarse threads of 36 mm outside diameter and 2 mm pitch
- (C) Metric threads of 36 mm pitch diameter and 2 mm pitch
- (D) Metric threads of 36 mm core diameter and 2 mm pitch
3 The designation M 20 means
- (A) Metric coarse threads of 20 mm outside diameter
- (B) Metric fine threads of 20 mm outside diameter
- (C) Metric threads of 20 mm core diameter
- (D) Metric threads of 20 mm pitch diameter
4 The largest diameter of external or internal screw thread is called
- (A) Major diameter
- (B) Minor diameter
- (C) Pitch diameter
- (D) None of the above
5 A screw is specified by
- (A) Major diameter
- (B) Minor diameter
- (C) Pitch diameter
- (D) Mean diameter
6 A washer is specified by
- (A) Outer diameter
- (B) Inner diameter
- (C) Thickness
- (D) Mean diameter
7 Machine bolts are
- (A) Through bolts with rough shank and used with nut
- (B) Used to prevent relative motion between two parts
- (C) Similar to stud
- (D) Turned into a threaded hole in one of the parts
8 The coupler of turnbuckle has
- (A) Right hand threads on both ends
- (B) Left hand threads on both ends
- (C) Left hand threads on one end and right hand threads on other end
- (D) No threads
9 Eyebolts are used
- (A) To prevent relative motion between two parts
- (B) To absorb shocks and vibrations
- (C) To lift and transport machines and heavy objects on shop floor
- (D) To prevent loosening of threads in bolted assembly
10 A stud is
- (A) Screw with long threads
- (B) Screw with circular head
- (C) Screw with hexagonal head
- (D) Headless screw with threads on both sides
11 Bolts are most suitable to carry
- (A) Shear
- (B) Axial tension
- (C) Bending
- (D) Shear and bending
12 The shock absorbing capacity of a bolt may be increased by
- (A) Increasing its shank diameter
- (B) Decreasing its shank diameter
- (C) Tightening the bolt property
- (D) Making the shank diameter equal to the core diameter of the thread
13 If core diameter of bolt is 13.8cm then its nominal diameter is given by?
- (A) 17.27mm
- (B) 15.34mm
- (C) 14.67mm
- (D) 16.34mm
14 Refer to figure. Two plates are fastened by means of two bolts. The yield strength of bolt is 400N/mm² and factor of safety is 4. Determine the permissible shear stress in the bolts.
- (A) 100N/mm²
- (B) 50N/mm²
- (C) 25N/mm²
- (D) 75N/mm²
15 Refer to figure. Two plates are fastened by means of two bolts. The yield strength of bolt is 400N/mm² and factor of safety is 4. Determine the size of the bolts.
- (A) 8mm
- (B) 9mm
- (C) 10mm
- (D) 11mm
16 The structure shown is subjected to an eccentric force P=5kN and eccentricity=500mm. The horizontal distance between two bolts is 200mm and vertical distance between bolts is 150mm. The yield strength of bolts is 400N/mm² and factor of safety is 3. Referring to figure, determine the primary shear force.
- (A) 625N
- (B) 1250N
- (C) 2500N
- (D) 1000N
17 Referring to figure, determine the secondary shear force.
- (A) 2000N
- (B) 2500N
- (C) 1500N
- (D) 5000N
18 Which of the following types is not fillet weld?
- (A) Butt joint
- (B) Lap joint
- (C) T-joint
- (D) Corner joint
19 In gas welding which of the following is generally used?
- (A) Oxygen-Hydrogen
- (B) Oxygen-Acetylene
- (C) Oxygen-Hydrogen or Oxygen-Acetylene
- (D) None of the mentioned
20 Rails in the field are generally welded by using
- (A) Thermit welding
- (B) Gas welding
- (C) Electric arc welding
- (D) Forge welding
21 Which type of joint is used if plate thickness is less than 5 mm?
- (A) Single V butt weld
- (B) Single U butt weld
- (C) Square butt weld
- (D) Double U butt weld
22 Calculate strength of the welded joint shown below, when 70 MPa is the allowable shear stress for the weld material.
- (A) 54.44 x 10^3 N
- (B) 77 x 10^3 N
- (C) 50 x 10^3 N
- (D) None of the above
23 Transverse fillet welded joints are designed for
- (A) Tensile strength
- (B) Compressive strength
- (C) Shear strength
- (D) Bending strength
24 Steels used for welded assemblies are
- (A) Medium carbon steel
- (B) Mild steel
- (C) High carbon steel
- (D) Alloy steel
25 The weakest plane in a fillet weld is
- (A) The throat
- (B) Side parallel to the force
- (C) Smaller of two sides
- (D) Side normal to the force
26 The cross-section of a standard fillet weld is a triangle with base angle of
- (A) 45 deg and 45 deg
- (B) 60 deg and 30 deg
- (C) 50 deg and 40 deg
- (D) 20 deg and 70 deg
27 The parallel fillet welds are designed for
- (A) Tensile strength
- (B) Shear strength
- (C) Bending strength
- (D) Compressive strength
28 The size of the filled weld is given by
- (A) Throat of fillet
- (B) Smaller side of triangle
- (C) Hypotenuse of triangle
- (D) Bigger side of triangle
29 In transverse fillet welded joint, the size of weld is equal to
- (A) 0.5 x throat of weld
- (B) Throat of weld
- (C) 2 x throat of weld
- (D) Sqrt (2) x throat of weld
30 When mild steel components are welded, the ratio of strength of the weld material to that of the parent body is
- (A) More than one
- (B) Less than one
- (C) Equal to one
- (D) None of the three