Page 61 - CITS - Fitter Trade Practical - Volume -2

FITTER - CITS

EXERCISE 64 : Layout the spacing for rivet holes to make
a single riveted lap joint

Objectives

At the end of this exercise you shall be able to
• calculate the distance of the lap, the distance between centre of first rivet and edges and the distance of
pitch as per BIS standard
• layout the spacing for rivet holes to make a single riveted lap joint.

Ensure the edges of the workpieces to be joined are free of burr and straight.
Calculate the distance of the lap.
Distance of the lap = 4 x Dia of the rivet (D)
Diameter of the rivet = 2.5 or 3t from the known thickness, calculate the dia of the rivet, and calculate the distance
of the lap.
Mark the line of distance of the lap parallel to the edge, on both workpieces using a scriber and a steel rule. (Fig 1)

Fig 1

Calculate distance of the rivet line from the edge of the sheet.
Distance of the rivet line from the edge = 2 x the diameter of the rivet (D)
Mark the rivet lines parallel to the edge, on both workpieces (Fig 2).

Fig 2

Calculate the distance of the first rivets from the side edge. Distance of the first rivet from the edge = 2 x dia of
rivet (D)
Mark the distance of the first rivets from the side edges on the rivet line, on both the workpieces using a divider.
Calculate the distance between two rivets i.e. pitch. Pitch = 3 x the dia of rivet (D)
Mark the pitch of the rivets on the rivet lines, on both workpieces (Fig 2) using a divider.
Punch the centre points of the reivets using a centre punch and a setting hammer.

Riveting snap head rivet

Objectives: At the end of this exercise you shall be able to
• make proper use of the dolly, rivet set and rivet snap to perform correct riveting
• form the rivet head in round shape, by applying the hammer blows properly by the ball peen hammer
• rivet snap head rivet to make the riveted joint tight without damaging the base metal.

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