Information

5/95e M/P 70168
Care should always be taken during installation of
pneumatic cylinders and valves to ensure that they are
fitted in such a manner that they are protected against dirt,
water or other contamination as well against mechanical
damage. The environmental temperature for normal
cylinders should not exceed 80° C, and the same applies to
normal valves. Cylinders fitted with heatresistant seals
may be used for temperatures up about 150° C.
Installation of the cylinders
In order to prevent premature wear of the seals and piston
rod bearings, the cylinders must be carefully aligned
during installation. It is absolutely imperative that should
be no forces acting at right angles to the cylinders axis. A
wiper is fitted in the bearing to prevent dirt penetrating
into the cylinder. If a cylinder is employed in a dirty
environment (cement dust, residues from flame-cutting
operations etc.) it is advisable to provide special protection
for the piston rod (a bellows sleeve may be used).
Every cylinder is authorized for a certain maximum
working pressure which may be exceeded.
Adjustable cushions are fitted in both ends of the
cylinders. When installing a cylinder care should be taken
to ensure that the cushions adjusting screws remain easily
accessible, so that the cushions can be adjusted at any time
to suit the working conditions.
Installation of valves
Main control valves, i.e. valves which control reversal of
cylinders, should be installed as close to the cylinders as
possible in order to eliminate unnecessary air
consumption. Under no circumstances valves serving as
limit switches may be used as stops.
Routing of pipework
Pipework in the main supply network in the plant should
be installed at a slightly inclined angle. Long runs should
be alternately inclined downwards and upwards. Any
condensate water then collects at the lowest points in the
pipework. At such points a pipe should be fitted leading
vertically downwards to a small condensate receiver. The
latter should be emptied from time to time. An automatic
drain valve will do this automatically if fitted in place of a
condensate receiver. Branches leading from the main line
to consumption points should be installed pointing
vertically upwards and then curving downwards. Do not
use bends of too small radius. Carefully blow out all pipes
before installing them, so as to remove any dirt and chips.
Do not hemp for making seals! Liquid sealing agents or,
still better, sealing tape (Fluflex or Diring) ensure that
contamination, such as fibres when hemp is used, does not
get into the pipework.
Installation and
maintenance instructions
for Norgren pneumatic products
Maintenance
As a rule Norgren cylinders and valves require nardly any
maintenance. All seals (o-rings and packing-rings) are
made of synthetic, oil-resistant rubber. However, the
condition of the compressed air determines the life of the
installation. For this reason the air used should be treated
so that it is suitable for the purpose in the interests of long
life. Clean air, free of water and containing oil fog, ensures
long service life for the equipment. A filter with water
separator incorporated in the line removes small particles
from the air and separates out water. The condensate
collects in a receiver mounted on the filter and should be
drained off from time to time. If an automatic drain valves
is mounted on the filter it is absolutely certain that it will
not be forgotten to drain off the condensate. The cleaned
air now has to have oil added to it. Every engineer knows
that sliding parts have to be lubricated and therefore
provides lubrication for bearings and other moving parts.
In a cylinder, too, the piston and piston rod slide, and the
slides in the valve also move. It is very often not
considered necessary to lubricate such parts- and then the
penalty is paid in the form of premature wear of packings
and bearing. In order to lubricate a pneumatic control
system properly a lubricator is installed in the air line; this
lubricator saturates the compressed air with a fine fog of
oil droplets. These droplets remain suspended in the air
and are carried to the lubricating points in the cylinders
and valves. The size of lubricator selected depends on the
volume of air flowing through the line and NOT on the
consumption. One must differentiate between consumption
per unit time and rate of flow per unit of time.
And now an example
Lubricators have a wide flow range, but care must still be
taken to match the size of lubricator to air flow, and it s
important to distinguish between consumption and air
flow. Thus if a circuit consumes 5 cubic feet of air per
cycle and this cycle occupies 10 seconds and occurs once
every two minutes, the average consumption is 2 ½ cfm
but the rate of flow is 30 cfm when calculating the
capacity of lubricator required. We recommend the
following grades of oil for use in the oilers:
Shell Oil Tellus C32 Fa. Shell
Aral Oil Vitam DE32 Fa. Aral
BP Oil Energol HLP32 Fa. BP
Esso Oil Nuto H32 Fa. Esso
Mobil Oil D.T.E. Oil Light Fa. Mobil Oil
or corresponding oils of other makes.
The micro-lubricators are suitable for oils with a viscosity
from 20 to 200 cSt at an operating temperature of 20° C.
Lighter oils should not be used, as in most cases an excess
of lubrication.