ADVANTAGES OF MECHANICAL LEATHER PACKINGS
Mechanical leather packings, because of the very nature of the material from
which they are produced, have advantages not possessed by other packings. The
hide from which leather for mechanical leather packings is made is a natural
product. Its individual fibers, each consisting of a bundle of fibrils, are
interwoven in a non-directional pattern that is unmatched by any other material.
Leather is pliable, tough and highly resistant to abrasion and wear.
Have Low Coefficient of
Because of an extremely low coefficient of friction, little heat is generated
when leather packings are used. This results in high efficiency and a long
life. The fibrous structure of the leather surface carries a film of the
actuating medium which in most cases functions as a lubricant and still
further reduces the coefficient of friction.
Leather packings operate smoothly and do not cause chattering at low pressures
and slow speeds. Because of their low coefficient of friction, they have a
very low static seizure and do not require a relatively high pressure to start
Readily Cold Flow
Leather packings, properly supported, because of the inherent natural strength
of the leather from which they are made, will withstand the highest pressures
to which any packing may be subjected with a minimum of cold flow or
Low in First Cost
Leather packings, due to their long life and the relative simplicity of die
and tooling requirements, are comparatively low in cost.
for Wide Range of Pressures
Leather packings are called upon and are obtainable
to operate against pressures ranging from a few ounces up to many thousands of
pounds per square inch. In general, the type of leather packing used with high
pressure requirements should be one recommended
by the packing manufacturer as it may involve the application of special
leathers and impregnancs.
Not Score or Abrade
Leather packings are non-abrasive and non-corrosive
and actually tend to polish the metal surfaces which they contact. Most other
packing materials operating under the same conditions have a tendency to score
the metal or abrade the packing.
Adaptable to Different Types of Service
Leather packings are impregnated with suitable materials to make them
adaptable to a wide range of operating conditions.
Since leather packings will not deteriorate due to either oxidation or
sunlight, they can be kept in stock without loss of their desirable and
Leather is unaffected by sub-zero temperatures and packings molded from it,
when properly impregnated will remain operable under those conditions.
Mechanical leather packings are called upon to operate against pressures ranging
from a very few ounces up to many thousand pounds per square inch.
Under the category of mechanical leather packings are found delicate regulator
diaphragms and some leather cup applications in which the actuating pressure
is measured in ounces. At the other end of the range are heavy hydraulic
applications involving pressures as high as 50,000 to 60,000 psi (pounds per
square inch). Leather packings on special applications have been used at
pressures as high as 140,000 psi.
Leather is unaffected by sub-zero temperatures and packings made from it can
therefore be used at these temperatures without cracking, breaking, or
shattering. Almost all leather packings can be used at temperatures ranging from
minus 30° F. to plus 150" F. Special packings are available for temperatures
ranging from minus 70° F. to 210°F.