Page 64 - CITS - Fitter Trade Practical - Volume -2

FITTER - CITS

Job sequence

• Cut the given material in two pieces to size 65 x 70 using hand lever bench shears and check the size using a
steel rule.

• Flatten the sheet on the dressing a plate by mallet.
• Deburr the edges using a flat smooth file.
• Layout the spacing for rivet holes to make double riveted lap joint using a scriber, a divider and a steel rule on
both the pieces of the sheet.
• Mark the centre point for the rivet holes using a centre punch and a setting hammer.
• Drill φ 4.2 mm holes at all the points on one piece of the sheet and two centre holes on another piece of sheet
using a portable drilling machine. (Fig 1)

Fig 1

• Deburr the holes with larger sized drill rotating it on the drilled holes by hand.
• Place the piece of sheet having all holes drilled above another such that the edges of the sheet coincides with
the marked line for lap. (Fig 2)

• Insert φ 4 mm snap head rivet in the centre hole. (Fig 2)

Fig 2

• Form the rivet head with the help of a rivet set and dolly using a ball peen hammer.
• Check that the two sheets are in line using a straight edge.
• Drill the remaining holes on the bottom piece of sheet through the holes, already drilled on the upper piece of
sheet.
• Deburr the holes with larger sized drill, rotating it on the drilled holes by hand.
• Insert the rivets in alternate holes and form the rivet heads one by one to make double riveted lap joint (chain)
with the help of a rivet set, a dolly and a ball peenm hammer. (Fig 3)

Fig 3

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CITS : C G & M - Fitter - Exercise 64