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Fig. 5-2: Three Ply Splice
Top cover
22° bias
Direction of belt travel
Recommended application and use
for the reverse skive
1. Used at the lead end of the top cover fill unless
the belt carries material in both directions – in this
case be sure to install reverse skive at the lead
end wherever needed.
2. Use a 45° cover skive.
3. Install the reverse skive when the cover gauge is
1/8" and greater.
Ply #2
Lead end reverse skive
4 in. (100 mm) wide top cover fill strip
Top cover
Ply #1
Ply #2
Ply #3
Bottom cover
Direction of belt travel DOT
Directional 45° cover skive
Direction of belt travel
4 in. (100 mm) wide bottom cover fill strip
Noodle placed over
each ply seam
Breaker & Inside
gum sheet
45° cover skive
Trailing end
Ply #1
Ply #3
2.
Illustration Fig. 5-2 shows a schematic of the typical
Three Ply Splice.
3.
The technique for splicing fabric belts using the Bias Step
Splice method is essentially the same for any number of
plies. A four-ply construction is illustrated in the sketches
and instructions that follow.
4.
Draw the master line.
a. A square and straight edge is generally used to mark
the master line on the belt as described in section III
of this manual.
b. After checking both edges, if there is a difference in belt
width, it can be halved and the result will usually give an
accurate line.
c. Check the master line by laying the square along
the opposite edge. As a final check, mark off the bias
lengths on each edge and check that the two diagonal
lengths are equal. Refer to Fig. 5-3.
Master line by straight edge and square
Straight edge
Master line
Square to
validate the
master line
is straight
1
2
3
4
5
6
7
8
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26
Fig. 5-3
5.
Measure off the bias length and draw the bias line to the
end of the master line on the opposite edge (Fig. 5-4).
This line marks the location of the top ply cut after the
cover gum is removed.
Fig. 5-4: Drawing the bias line
Master line
45° cover skive
Bias line and
1st ply
2nd ply
3rd ply
4th ply
V. Belt Splicing
Procedures
Fabric Belt Bias Step Splice
Splice Dimensions
Specified splice dimensions for the various splice types are
documented in the Heavyweight Conveyor Belt Catalog and on
the specified splice schematic.
Splice Bias
1.
The bias is a critical part of the splice and is typically
designed to match the bias of most vulcanizers.
2.
The entire Top and Bottom Insert Rubber Strip must be
cured in a single setting of the vulcanizer. When needed,
to cure the splice in a single cook, the bias length may be
adjusted/shortened. The recommended bias lengths are
shown in the splice schematics, but they can be adjusted
up to 2 in. or 3 in. (50mm or 75mm) if necessary
to accommodate the vulcanizer.
NOTE: Bias can be made to match the bias on the vulcanizer. The
most common are 20° and 22°. The 22° bias angle can be achieved
by multiplying the belt width by 0.40. A shorter 20° bias angle can
be achieved by multiplying the belt width by 0.36.
An example of the 22° bias angle is: 72 in. belt width x 0.40 = 28.8 in.
(round to 29 in.) bias. An example of the 20° bias angle is: 72 in. belt
width x 0.36 = 26 in..
3.
The Bias Step Splice is not currently recommended for the
heavier carcass belts with fabric plies greater than 250#.
These fabric/belt types require the Full Carcass Long Life
Finger Splice method. The Full Carcass Long Life Finger
Splice method allows for better flexibility in the splice as
the belt travels around pulleys while under great tensions.
Belts such as Fortress XP™ and Plylon® Plus (900/2,
1350/3, 1500/3 and 1800/4) require the Long Life Full
Carcass Finger Splice.
Procedures
1.
The illustration Fig. 5-1 below shows the Bias Step Splice
and how the plies from each belt end are stepped down
and aligned to make the splice.
Fig. 5-1: Bias Step Splice
50 mm
45° cover skive
top ply
16 in.
(406 mm)
top ply
16 in.
(406 mm)
#2 ply
16 in.
(406 mm)
#2 ply
16 in.
(406 mm)
#3 ply
16 in.
(406 mm)
#3 ply
16 in.
(406 mm)
#4 ply
16 in.
(406 mm)
#4 ply
16 in.
(406 mm)
#5 ply
16 in.
(406 mm)
#5 ply
16 in.
(406 mm)
2 in.
(50 mm)
Top Cover of the Belt
45° cover skive
Bottom Cover of the Belt
45° cover skive
45° cover skive
Top Cover of the Belt
Bottom Cover of the Belt
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Conveyor Belt
Fabric Splice Manual
Conveyor Belt
Fabric Splice Manual