INTERVIEW SHORT QUESTION ANSWERS: RIVETED JOINTS

INTERVIEW SHORT QUESTION ANSWERS: RIVETED JOINTS

Q.Write down the important terms used in the design of riveted joints.

A.

(i) nominal pitch or short pitch

(ii) Medium pitch

  • Long pitch
  • Row pitch or back pitch or transverse pitch
  • Diagonal pitch
  • Margin
  • Marginal distance
  • Strap thickness
  • Plate thickness
  •  shank diameter
  •  tail
  •  head
  • Types of rivets
  • Caulking
  • Fullering
  • Clearance before making the second head
  • Types of riveted joints
  • Lap joint-single/double/triple riveted
  • Butt joint with single strap—Single/double/triple riveted
  • Butt joint with double strap– Single/double/triple riveted
  • Chain riveting
  • Zigzag riveting
  • Strength of one rivet
  • Riveted joint efficiency
  • Tearing efficiency
  • Shearing efficiency
  • Crushing efficiency
  • Overall riveted joint efficiency
  • Design of riveted joints
  • Cold working of rivets (for diameter less than 12 mm)
  • Hot working of rivets

 

  1. List the various assumptions used in the design of riveted joints.

A.

(i) Load is uniformly distributed in all the rivets.

(ii) Failure of rivets is by shear.

  • Shear stress is uniformly distributed over the gross area of the rivet.
  • Bending of rivets is neglected.
  • Bearing stress is uniform over the projected area of the rivet.
  • Rivet hole is completely filled after the rivet is driven into the hole.
  • Stresses in the plate is also assumed to be uniform
  • There is no friction between the plates being connected.
  • Riveted joints are used in joining light metals.

Q. List the applications of riveted joints.

A.

These are used in the followings:

  • Structures
  • Pressure vessels
  • Ship building
  • Tanks
  • Bridges
  • Boilers
  • Air crafts
  • Railway wagon and coaches
  • Buses and trucks
  • Used with wood, metal and plastic.

Q. List the advantages and disadvantages of riveted joints.

A.

Advantages of riveted joints

  • Riveting is cheap.
  • It is a superior method of fastening.
  • Rivets are easy to install.
  • Low cost of maintenance
  • Available in variety of materials, types and sizes
  • Riveted joints are reliable since these are permanent joints.
  • These can with stand environmental conditions of heat, rain and dust over a long period.
  • Riveted joints are light weight and high strength.
  • These are used with wood, metal, plastic but more with light materials.

 

Disadvantages of riveted joints

  • Needs skilled persons to do riveting.
  • There can be a leakage problem in case of pressure vessels and boilers (it can be overcome by special techniques of caulking and fullering).

 

Q. List the materials of rivets.

A.

Material of the rivet should be tough and ductile. Special materials are used as per CODE practice in boilers. The following materials are used in different applications.

(i) Wrought iron

(ii) soft steel of less hardness

  • Copper
  • Brass
  • Aluminium
  • Stainless steel

Q. What are assumptions made in the design of a welded joint?

A.

(i) Uniform distribution of stresses in the critical throat plane area

(ii) Failure of fillet welds takes place at the minimum area i.e. the throat area.

  • Failure is due to shear only.