Seepex BN 5-12 Series, Руководство по эксплуатации и техническому обслуживанию

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Number IN-3A
Page 1
1 2 9 5 0 W . E I G H T M I L E R D . • O A K P A R K / M I • 4 8 2 3 7 - 3 2 8 8
P H O N E : 2 4 8 - 3 9 9 - 8 0 0 0 • F A X : 2 4 8 - 3 9 9 - 7 2 4 6
FOR TRERICE PRESSURE GAUGES
Trerice Pressure Gauges are offered in a variety of styles, sizes, and bourdon tube materials.
Gauges should be selected carefully to meet the demands of the situation and, in particular, the
range should be selected so that the working pressure is approximately 50% of the total range.
Principles of Operation
Trerice Pressure Gauges utilize the bourdon type tube construction. When this bourdon tube is
subjected to the pressures of the media being measured, the bourdon tube flexes and this motion
is transmitted to the pointer through a mechanical multiplication-type movement.
Installation
When installing a Trerice Pressure Gauge, care should be taken not to use the instrument case
itself to wrench in the pressure connection. Always use a wrench fitted to the flats on the socket
for this purpose. If the instrument is used to wrench in this connection, it is quite possible that
the movement alignment will be disturbed. The instrument should be mounted upright as nearly
as possible in a vertical plane; however, the instrument will read correctly when mounted with 15
°
of the vertical plane.
The gauge may be installed either surface mounted, flush mounted or rigidly on the line. When
surface mounting the instrument on a wall or a panel, make sure the instrument is connected free
from any piping strains or stresses. Also check to make sure the mounting surface is flat, and
that the instrument, if surface mounted, is mounted on the three pads provided for three point
suspension.
Care should be exercised in selecting a location that is as free from vibration as possible.
Vibration is the pressure gauge’s worst enemy, and these vibrations will tend to wear out the fine
gear sections within the gauge. If there is a vibration in the pipeline and the gauge is remotely
located, it is advisable to a small section of flexible tubing between the gauge and the line to
absorb these vibrations. When a gauge is used on a media is used on a media where pressure
pulsations exist, it is recommended to use either: (1) a choke screw, (2) pressure snubber,
(3) pressure impulse dampener, or a (5) needle valve. Any of the aforementioned will reduce
wear on the gauge.
When a gauge is used on steam service, it is advisable to use a coil siphon filled with water
between the gauge and the pressure media. In selecting a gauge, the method of construction
must be considered; that is, solder, silver, braze or welded construction.
When the gauge is located in a corrosive atmosphere, care should be taken in ordering the
instrument weatherproofed to restrict the entry of these corrosive fumes into the case. In
measuring the pressure media of corrosive materials, the gauge should ordered with socket and
bourdon tube specifications suitable to resist these corrosive media.
Maintenance
Pressure gauges should be kept clean by replacing glass, rings, etc, to keep internal parts from
outside elements. Pressure gauge movement or linkage should never be oiled as oil attracts dirt
and causes the movement to become gummy after a period of time. This will cause the gauge to
act sluggish. If a gauge requires attention due to sluggishness, usually cleaning the movement
with carbon tetrachloride or some similar solvent will correct the problem.
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