Page 28 - 2010-2022 hose manufactureing ability and guide

GENERAL

Chapter 1

A hose is a reinforced, flexible conduit used to move materials from one point to another or to
transmit energy. It is flexible to accommodate motion, alignment, vibration, thermal expansion and
contraction, portability, ease of routing, and ease of installation.

Most hoses are made up of three elements: (1) a tube, (2) reinforcement, and (3) an outer cover.
Each of these components is usually adhered to the adjacent components by bonding agents or
thin layers of specially compounded rubber. Figures 1-1 through 1-5 show five types of hose.
Components are designated as follows: “A” - tube, “B” - reinforcement, “C” - cover.

Tube Figure 1-5 shows how a layer of the
reinforcement can also serve as a cover for fire
The tube is the innermost rubber or plastic hose. The prime function of the cover is to
element of the hose (see Figures 1-1, 1-2, 1-4 protect the reinforcement from damage and the
and 1-5). The tube may be placed over environment in which the hose will be used.
reinforcing elements as in Figure 1-3. For Covers are designed for specific applications
suitable service, the tube must be resistant to the and can be made to be resistant to oils, acids,
materials it is intended to convey. The abrasion, flexing, sunlight, ozone, etc.
characteristics of the rubber or plastic
compound from which the tube is made and the MANUFACTURING MATERIALS
thickness of the tube are based on the service The basic materials in the manufacture of
for which the hose is designed. hose are rubber, plastics, textile yarns, textile

Reinforcement fabrics, and metal in the form of wires and
cables. Throughout this book, the term “rubber”
Reinforcement can be textile, plastic, or will be used in its broadest sense. This will
metal, alone or in combination, built into the include all elastomeric materials that are
body of the hose to withstand internal pressures, compounds of natural or synthetic elastomers or
external forces, or a combination of both. The combinations of these materials.
type and amount of reinforcing material used Rubber
depends on the method of manufacture and on
the service requirements. For example, a To provide a wide range of physical properties
residential garden hose does not need the same for specific service needs, elastomers are mixed
level of reinforcement as required for high with various chemicals. Space does not permit
pressure air hose used in construction and discussion of the compounding ingredients or
mining applications. Figures 1-1, 1-2 and 1-4 compounding methods, so only the basic
show reinforcement applied over the tube. elastomers will be discussed. There are many of
Figure 1-3 is a good example of divided these available to the hose manufacturer. In
reinforcement with part under the tube and part addition, many types may be blended in almost
over it. unlimited combinations to obtain the most
desirable properties.
Cover
The cover is the outer element and can be made

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