General Information
In order to obtain the best service from any
particular hose application, two important
conditions must be fulfilled:
1.
To select the right hose for the job.
2.
To make sure, that after having obtained the
right hose, it is fitted correctly and used in a
proper manner.
When considering a particular hose application,
the following basic factors should be considered:
1.
Inside diameter.
2
.
Outside diameter.
3.
Materials being conveyed (e.g., air, water, acids,
oils, steam).
4.
Precise composition of substance (important in
the case of oils, solvents, spraying media, foods,
beverages, petroleum products, gases, etc.).
5.
Concentration (in the case of chemicals).
6.
Maximum temperature of substance.
7
.
Maximum pressure (including any possible
surge or back pressure).
8.
Degree of vacuum (in the case of suction hose).
9.
External conditions. The scope of this factor is
possibly the widest of all and covers such things as:
Abrasion
Climactic conditions
Direct heat
Radiated heat
Contamination from oil, grease, solvents,
acids, etc
End loads
Flexings — degree and cycle
Crushing conditions
Kinking conditions
10.
Details of couplings (particularly in specialized
applications).
Steam Hose
Air, steam and water hoses are the three types of
hose most used in industrial plants. The following
instructions apply in general to these types of
hose. Since steam service is usually the most
severe in the average plant, particular attention
is directed to steam hose. In selecting a hose
for a steam installation it is important that the
type recommended is sufficient to handle the
maximum working pressure. Your Continental
ContiTech representative will assist in making
recommendations.
At elevated temperatures, steam severely affects
rubber hose of all types, so it is important that
temperature be considered in the choice of a
steam hose. High steam temperature and pressure
can cause deterioration in certain reinforcing
members used in hose and a relatively small
increase in temperature can greatly affect hose
performance.
The steam pressure is important in that it
determines the minimum temperature condition
under which the hose will be used. If the steam is
saturated, its temperature is directly related to its
pressure. The temperature may be determined
from the Saturated Steam Table on page 322.
However, if steam is superheated, the degree
of superheating must be known to determine
the actual temperature which the hose must
withstand.
The flex factor takes into consideration the
magnitude of the flexing and its time cycle. A
flexing that is rapid and continuous, even though
of small magnitude, would be considered as severe
as flexing that is large in magnitude but with an
extremely long time cycle. The degree of flexing is
an important factor in the ultimate life of the hose.
Refer to R.M.A. Technical Information Bulletin
#1
P-11-1.
Air Hose
Many fine types of air hose, equipped with tough,
abrasion-resisting covers are offered tube stocks
which will successfully resist oil mist, if present.
Where tools are lubricated through hose, only the
very best quality air hose with highest grade oil-
resisting tube should be used. The recommended
working pressure should be sufficient to withstand
the maximum pressures encountered.
Water Hose
In the selection of the correct water hose for any
service, the same principles apply as for air and
steam hose.
Suction Hose
Most Continental ContiTech vacuum or suction
hose are designed to withstand full vacuum.
However, in some of the lighter styles, less than full
vacuum is recommended.
Use the information in this catalog to help
determine the best hose for your application. To
assist your efforts to collect the data necessary
to make a proper hose recommendation, use the
form on the next page.
How to Select the Right Hose
334
Appendix
C
Air & Multipurpose
General Purpose
Heavy Duty
Push-on
Chemical Transfer
Cleaning Equipment
Food
Transfer
Washdown
Marine
Material Handling
Abrasives
Bulk Transfer
Cement & Concrete
Mining
Petroleum
Aircraft Fueling
Dispensing
Dock
Transfer
Spray
Steam
Vacuum
LPG Delivery
Water
Discharge
Suction & Discharge
Washdown
Welding
Coupling Systems
Equipment
Appendix