Greenlee 884 Manual De Instrucciones página 9

Bending Instructions (cont'd)
Laying Out Offset Bends (cont'd)
Calculating Shrink
When making offsets, it is common practice to make
the offset as close to the obstruction as possible. When
laying out an offset and working away from an obstruc-
tion, no special provisions are required. However, when
approaching an obstruction, the conduit "shrinks."
CENTER-TO-CENTER DISTANCE
To get the second bend closer to the obstruction,
both bends must be adjusted forward. The amount of
this adjustment is referred to as "shrink." The follow-
ing illustration shows the same installation with shrink
factored in.
Bending marks have been moved forward.
Second bend is closer to the obstruction.
Greenlee / A Textron Company
OFFSET
ANGLE
SHRINK
884 and 885 Hydraulic Benders
To find the center-to-center distance and the amount of
shrink per inch of depth for a particular offset, consult
the "Greenlee Offset Multiplier and Shrink Table."
Greenlee Offset Multiplier and Shrink Table
Offset Angle
10°
15°
22-1/2°
30°
45°
60°
To use this table, determine the depth of the offset
and the degree of bend. Calculate the center-to-center
distance by multiplying the amount of the offset by
the multiplier (center column). Calculate the amount of
shrink by multiplying the shrink per inch of offset depth
(right column) by the offset depth.
Example: 6" offset
30° bend
Multiplier for 30°: 2
Multiply the amount of offset by the multiplier to find
the center-to-center distance:
2 x 6 = 12
Find the amount of shrink per inch of offset in the
table:
1/4"
Multiply the shrink per inch by the amount of the
offset:
6 x 1/4" = 1.5"
Mark the conduit: Place the second bending mark
1.5" past the obstruction. Measure back toward the
starting point, and place the first bending mark 12"
before the second bending mark.
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4455 Boeing Dr. • Rockford, IL 61109-2988 USA • 815-397-7070
Shrink Per Inch
Multiplier
of Offset Depth
6.0 1/16"
3.86 1/8"
2.6 3/16"
2.0 1/4"
1.4 3/8"
1.2 1/2"
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Second
bending
mark is
1.5" past the
CENTER-TO-CENTER
obstruction.
DISTANCE IS 12"
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