Page 105 - 2010-2022 hose manufactureing ability and guide

plasticity: (1) a measure of the resistance to pressure, operating: see: working pressure.
shear of an unvulcanized elastomer; (2) a pressure, proof: a specified pressure which
property of vulcanized rubber to retain a shape exceeds the manufacturer's recommended
or form imparted to it by a deforming force. working pressure applied to a hose to indicate
plasticizer: a compounding ingredient which its reliability at normal working pressure. Proof
can change the hardness, flexibility, or pressure is usually twice the working pressure.
plasticity of an elastomer. pressure, service: see: working pressure.

plastometer: (1) an instrument for measuring pressure, working: the maximum pressure to
the viscosity of raw or unvulcanized rubber; (2) which a hose will be subjected, including the
an instrument for measuring the hardness of momentary surges in pressure which can occur
vulcanized rubber. during service. Abbreviated as WP
plied yarn: a yarn made by twisting together pricker mark: a perforation of the cover of a
in one operation two or more single yarns, hose performed before or after vulcanization.
ply: (1) a layer or rubberized fabric; (2) a layer printed brand: see brand.
formed by a single pass through a single deck
of a yarn, cord, or wire braiding machine; (3) a processability: the relative ease with which
layer formed by a single pass through a single raw or compounded rubber can be handled in or
head of yarn, cord, or wire knitting machine; (4) on rubber processing machinery.
a seamless woven jacket consisting of warp and
filler yarns and/or wire; (5) a layer consisting of
multiple strands of cord or wire closely spaced; pressure, operating: see: working pressure.
(6) a layer formed by winding a single strand of pressure, proof: a specified pressure which
cord or wire closely spaced; (7) a single yarn in exceeds the manufacturer's recommended
a composite yarn; (8) a layer of unvulcanized working pressure applied to a hose to indicate
rubber. its reliability at normal working pressure. Proof

ply adhesion: the force required to separate pressure is usually twice the working pressure.
two adjoining reinforcing members of a hose. pressure, service: see: working pressure.
ply separation: a loss of adhesion between pressure, working: the maximum pressure to
plies. which a hose will be subjected, including the
momentary surges in pressure which can occur
pock marks: uneven blister-like elevations,
depressions, or pimpled appearance. during service. Abbreviated as WP
polymer: a macromolecular material formed pricker mark: a perforation of the cover of a
by the chemical combination of monomers hose performed before or after vulcanization.
having either the same or different chemical printed brand: see brand.
composition.
processability: the relative ease with which
popcorn: a term common to steam hose where raw or compounded rubber can be handled in or
small eruptions within the tube wall rip or tear on rubber processing machinery.
material, leaving cavities in the tube.

porous tube: (1) the physical condition of a
hose tube due to the presence of pores; (2) a proof pressure: a specified pressure which
hose tube that has low resistance to permeation. exceeds the manufacturer's recommended
pre-cure: see semi-cure and scorch. working pressure applied to a hose to indicate
its reliability at normal working pressure. Proof
preproduction inspection or test: the pressure is usually twice the working pressure.
examination of samples from a trial run of hose
to determine adherence to a given specification, proof pressure test: a non-destructive pressure
for approval to produce. test applied to a hose to determine its reliability
at normal working pressures by applying
pressure, burst: the pressure at which rupture pressures which exceed the manufacturer's rated
occurs.
working pressure.

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