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PIPE PATCHES | Up
Aviation Boatswains Mate F - Aviation theories and other practices | Next
Advantages of the Plastic Patch |
Figure 2-23.—Jubilee pipe patches.
In addition to the repair or patching of piping, certain
materials are included in the kit that may be used to
patch small cracks and ruptures in flat metal surfaces.
Materials in the kit may be obtained separately
through appropriate supply channels whenever a need
arises to replace them. You need not obtain another
completely new kit. A complete kit contains the fol-
lowing materials:
4 cans of liquid resin, 400 grams each
4 cans of liquid hardener, 100 grams each
4 cans of paste resin, 300 grams each
4 cans of paste hardener, 75 grams each
1 piece of woven roving cloth 24” x 10”
1 piece of void cover, 8” x 36”
1 piece of polyvinyl chloride (PVC) film, 36” x 72”
1 chalk line, 1/8-lb
4 pairs of gloves
2 eyeshields
4 wooden spatulas
A description of the basic materials and factors
related to plastics is necessary for you to more thor-
oughly understand the discussion of the kit and its
use.
RESINS AND HARDENERS.— The liquid and
paste resins are of the epoxy type. The liquid and
paste hardeners are chemical compounds used to
harden the resins. The resins and the hardeners are
packaged in premeasured amounts. For proper mix-
ture and better results, the complete contents of the
hardener in the smaller can should be mixed with the
complete contents of the resin in the larger can.
CAUTION
Do not mix hardener with resin until all
preparations have been completed, and do not
intermix liquid resin and paste hardener or
paste resin and liquid hardener.
When the hardeners and the resins are mixed, a
chemical reaction occurs that causes the mixture to
harden (liquid mixture, approximately 12 minutes;
paste mixture, approximately 17 minutes).
VOID COVERS.— The void cover is resin-
treated glass cloth that can be cut and formed to cover
the damaged area and is sufficiently rigid to give
support to the patch.
WOVEN ROVING CLOTH.— The woven rov-
ing cloth is made of a short staple glass fiber woven
into a thick, fluffy cloth. During the application of a
plastic patch, this cloth is coated with the resin-hard-
ener mixture and either wrapped around or placed
over the damaged area. The glass cloth provides the
main strength of the patch and also provides a means
of applying the resin-hardener mixture.
FILM (PVC).— The plastic film is a thin, trans-
parent polyvinyl chloride material that is used as a
separating film for the flat patch to prevent the patch
from sticking to the backup plate or other supports. It
is called PVC. In the pipe patch it is used to cover the
entire patch and keep the activated resin around the
patch. Kraft wrapping paper may be used as a substi-
tute if necessary.
1 sheet of emery cloth, 9” x 11”
Chemical Reaction of the Plastic Patch
1 pair of scissors
4 tongue depressors
When the resins and the hardeners are mixed to-
gether, a chemical reaction begins. This reaction is
1 instruction manual
exothermic, meaning heat is given off. For about 12
2-15
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