12:24 PM , Posted in Reamers and its types
A reamer is a rotating cutting tool generally of cylindrical shape which is used to enlarge and finish holes to accurate dimensions to previously formed hole. It is a multiple edge cutting tool having the cutting edge on its periphery.
Parts of Reamer:
A reamer consists of three mean parts:
1. Fluted section
The fluted part consists of chamfer, starting taper, sizing section and back taper length. Chamfer length or bevel lead insures proper and easy entry of the reamer into the hole. The main cutting action of reamer is done by starting taper, the sizing section and to guide the reamers and also smooth or size the hole. The back taper reduces friction between reamers and the whole surface.
Types of Reamers:
There are following types of reamers:
· Hand Reamer
· Machine Reamer
· Chucking Reamer
· Fluting Reamer
· Expanding Reamer
· Adjustable Reamer
· Shell Reamer
1: Hand Reamer:
These reamers are operated by hand with a tap wrench fitted on the sequence of the reamer. The work is hold in a vice. The flutes may be straight or helical. Shank is straight with a square tang for the wrench.
2: Machine Reamer;
These are similar to hand reamer, except that the shank is tapered.
3: Chucking Reamers:
These are machine reamers with shorter flutes. These may be either of the type known as rose reamers or fluted reamers. These are using for heavy roughing cuts.
4: Fluting Reamers:
There the holder are not rigid but are fluting this permits the reamer. To flow the previously made hole naturally and without restrained resulting in a better hole.
5: Expanding Reamers:
These reamers allow slight increase in their size to allow for wear to remove an extra amount of material. For this the body of the reamers is bored tapered and is slitted. A taper plug runs through the hole end is operated by a screw so that it acts as the expander.
6: Adjustable Reamers:
In these reamers separate blades are inserted in the grooves provided in the body of the reamer. The blades can be moved up or down of the reamer.
7: Tapered Reamers:
These reamers are used to finish the taper holes for cutting the taper things used to secure the collars, pulleys etc to the shaft.
8: Shell Reamers:
Solid reamers (upto about 20mm diameter or usually made of Hss) to reduce the cost of larger reamers the cutting portion is made as separate shell which are mounted on standard shanks made of lower cost steel. These reamers are however do not very rigid and accurate inserted tooth or plates in shells in further reduced the cost of reamers can tip with cemented carbides.