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Best Practice Number 4
Allow cements and solvent to dry completely
before assembling the splice. When checking
the cement for wetness/dryness, never use
the palm of the hand or the palm side of the
fingers. Oils may be transferred to the surface,
which may reduce the adhesion value in this
area. It is recommended to use the back side
of the fingers.
When a belt splice is assembled and
cured before the cement has had
sufficient time to dry, the heat from the
vulcanizer will cause the solvents and
carriers in the cement to vaporize and
form bubbles / blisters. These bubbles
/ blisters are called “ply and/or cover
blows.” They will prevent adhesion
between the plies and covers. If the
surface area of the ply or cover blow
is large enough and/or numerous, the
strength of the splice is severely limited.
Ply and cover blows can also occur
when cements and solvents are not
allowed to reach room temperature after
removal from cold storage because
water condensation occurred on the cold
surface.
Reliable splicers will allow sufficient time
for cements to dry before assembly
and for cold materials to warm up.
Additionally, conscientious splicers will
not try to accelerate the drying process
by using heat guns or hair dryers, since
they can cause a skin to form on the
surface of still-wet cements. Space
heaters may be used to accelerate
cement-drying time, as long as safety is
not compromised in any way.
Best Practice Number 5
Avoid over-prodding the fabric when lifting
the plies.
The right tools and methods will ensure that the fabric plies are
not damaged when they are lifted. Prodding tools must have
smooth, rounded corners. Prodding tools should be checked
for possible burrs or nicks before each use.
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Installation, Maintenance & Troubleshooting Guide
Maintenance