Page 141 - Turner 1st sem Practicals

Production & Manufacturing Exercise 1.3.40
Turner - Turning

Reaming in lathe using solid and adjustable reamer
Objectives: At the end of this exercise you shall be able to
• drill a hole to size leaving allowance for reaming
• ream through hole with a hand reamer
• check the reamed hole by using a plug gauge
• enlarge the reamed hole by dia 0.1 mm using adjustable reamer.

Job sequence

• Hold the job in a 4 jaw chuck and true it by holding • Drill through hole in the job with Ø 15.75 mm drill
it about 25mm outside the chuck. bit after drilling a pilot hole of Ø10 mm.
• Face one end and turn Ø 30 ± 0.2 mm to the • Chamfer the drilled hole 1 x 45°
maximum length.
• Fix the Ø 16H7 hand reamer in the tailstock,
• Reverse the job and reset it. supporting with the dead centre.
• Face the other end to 30 ± 0.2 mm length. • Ream the hole by using sufficient coolant.
• Turn the outside dia. 30 ± 0.2 mm to the remaining • Give uniform hand feed while reaming.
length.
• Check the hole with a ‘Go’ and ‘No-Go’ plug gauge.
• Hold the centre drill in a drill chuck mounted on to • Enlarge the reamed hole using adjustable reamer
the tailstock barrel, and centre drill the work.
to size of Ø 16.1 mm.
• Check the surface finish, comparing the roughness
with the standard surface roughness set.

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