Bending Basics - Greenlee 881GX Cam Track Manual De Instrucciones

Basics of Bending
The following drawings, instructions and bending tables are intended to provide the information necessary to set up
the most common types of bends. The "Special Bending Tables" at the back of this manual, contain precise mea-
surements used for finding the marks for most common bends. Some types of bends have their own tables that
provide numbers for finding the bending marks. Below are some of the most common terms used in bending.
Glossary
Stub/Stub-Up/Rise— The distance
from the end of the vertical section of
conduit or pipe to the bend; mea-
sured from the end to the center line,
inside edge, or outside edge of the
conduit or pipe.
Leg Length—The distance from the
end of a horizontal section of conduit
or pipe to the bend; measured from
the end to the center line, inside edge,
or outside edge of the conduit or pipe.
Gain - The difference between the right
angle distances A & B and the shorter
distance C. Because pipe bends in
a radius and not at right angles, the
C
A
length of pipe needed for a bend will
not equal the total determined length.
B
Springback—The amount, measured
in degrees, that a conduit or pipe
tends to straighten after pressure
is released on the bender ram. For
example, a 90° bend, after pressure is
released, will spring back about two
degrees – to 88°.
O.D.—The size of any piece of
conduit or pipe as measured
by its outside diameter.
Height/Depth of Offset - The distance that the conduit
or pipe must be re-routed to avoid an obstruction.
Center-to-Center Distance—the distance between the
successive bends that make up an offset or a three-
bend saddle.
A
52093598 Rev 00
Snug-up - The process of securing the conduit between
the shoe and saddle by advancing the ram enough
to keep the conduit in place but not enough to start
bending.
Ram Travel - The distance that the ram of a hydraulic
bender must move to reach a specific bend angle.
Developed/Determined Length -The actual length of
the pipe that will be bent.
Min. Stub Length - A stub must be equal to or larger
than this number to avoid crushing threads and bad
quality bends.
Deduct - A calculated number to account for gain while
bending. This number is specific to the size and type of
conduit being bent.
Bend Angle/Angle of Bend - The target bend angle .
Kick - A bend, usually less than 45
the direction of a section of pipe.
Center Line - The imaginary line running through the
center of the conduit.
Bend Radius - The radius as measured from where the
center of the bend is located. This is a fixed number
based on the bending shoe.
Dog Leg Bend/Wow - A bend, usually no more than
45
not on the same plane.
Large Sweep Bends - Any bend which exceeds the
radius of one-shot 90° bending shoes supplied with
one-shot hydraulic power benders.
Comeback - When making a 90° bend having a
definite leg length (or rise) the center of the bend must
be located when using certain benders. To do this, first
measure the leg length from the end of straight section
of pipe. Then, "come back" 1/2 the gain to locate the
center of the bend.
Degree indicator - This is an instrument designed
to indicate the exact degree of bend while it is being
made.
H
Protractor - Made for use with Benders mounted on
Bending Table. Measures degrees – also has scale
for 18°, 20°, 21° and 22° bends when using to make a
large sweep bend.
Segment Bend - Any bend formed by a series of
bends of a few degrees each, rather than a single one-
shot bend.
© 2022 Greenlee Tools, Inc.
Cam Track® Hydraulic Bender
, made to change the direction of a section of pipe
o
made to change
o,
15