3 Functional Description
A coiled, drawn brass or stainless steel tube filled with the fluid or gas being monitored is
deformed to an extent depending on the pressure exerted by the fluid or gas. The resulting
movement of the coil is transmitted to an indicator mechanism with a graduated display.
4 Installation
For connections with cylindrical screw threads, use suitable gaskets to seal the pressure gauge
connections to the sealing face. For connections with tapered thread (e.g. NPT screw thread),
apply a sealing component such as Teflon tape directly to the screw threads (EN 837-2). In
order to be able to bring the measuring device into a position where it can be most easily read,
we recommend the use of a tension bushing or gland nut.
During installation and removal, pressure gauges must not be turned by the housing. Be sure
to only tighten and loosen gauges with suitable wrenches at the hexagonal drive points
provided for this purpose.
If the pressure gauge is to be installed below the pressure tapping point, then the process line
must be thoroughly flushed out first to remove any foreign objects before the gauge is
installed. Some device models have a pressure-relief opening that can be vented and closed to
equalize the internal pressure. In as-delivered condition, this pressure-relief opening is closed.
Before checking these devices and/or after installation but before placing them in service,
these devices must be vented (refer to label on housing). When pressure testing or purging
piping systems or tanks, make sure that the pressure gauge is not subjected to pressure
beyond the upper scale value. If this cannot be ensured, the pressure gauge must first be
isolated or removed from the system. Before removing the pressure gauge, be sure to relieve
the pressure in the measuring element. To do this, it may also be necessary to relieve the
pressure in the process line.
Caution:
Exposure to residue and deposits of materials being measured may pose a
danger to people, the environment and the apparatus.
Be sure to follow proper safety procedures. Pressure gauges with measuring elements
filled with water or mixtures containing water must be protected against frost.
PMR06-~1.SAM
18.05.06 Page 3
