(3) Expansion reamers. Expansion reamers (fig 24) are adjustable and their
sizes may be changed by 0.125 inch (1/8 inch) for a 1-inch reamer and by 0.3125
inch (5/16 inch) for a 2-inch reamer. The expansion reamer is made of carbon steel
and has longitudinal cuts in some of its flutes. It is hollowed out and threaded
to receive a tapered screw plug. The diameter of the reamer is changed by screwing
in or backing out the screw plug. These reamers are issued with spiral flutes in
two sizes--19/32-and 1-1/4-inch diameters. A straight flute with a floating pilot,
having a range of 1/2 to 17/32 inch and having a length of 9 inches, is also issued.
(4) Adjustable blade reamers. The blades of an adjustable reamer (fig 24)
are separate from the body and are fitted into grooves in the threaded shank of the
tool. Adjusting nuts below and above the blades control the diameter of the
reamer. These reamers are issued with straight or spiral flutes, with or without a
floating pilot, in several sizes. Spiral flute adjustable reamers are issued in
sizes from 0.730- to 0.780-inch range up to 0.980- to 1. 030-inch range. Straight
flute adjustable reamers are issued in sizes from a 1/2-to 9/16-inch range up to a
15/16- to 1-inch range in steps of 1/16 inch. They are also issued in steps of
1/16 inch from a 15/32- to 17/32-inch range up to a 1-25/32- to 2-3/32-inch range.
Adjustable reamers are available in sets. One set contains five spiral flute
reamers with floating pilots on solid mandrels ranging from 0.730 to 1.030 inches.
Another set of the same type contains eight straight flute reamers ranging in size
from 1/2 to 1 inch. Two other sets have reamers with lettered sizes A to H and A
to K, 15/32- to 1-1/16-inch range and 15/32- to 1-17/32-inch range, respectively.
The latter two sets do not have floating pilots or mandrels.
(5) Pipe reamers. Pipe reamers (fig 25) are made of carbon steel, are
tapered, and have straight or spiral flutes. They are issued in three sizes: 1/8-
to 1-inch pipe capacity, 1/4- to 1-1/4-inch pipe capacity, and 1/4- to 2-inch pipe
capacity. Most pipe reamers are designed to receive a T-handle.