ARI Armaturen ARImetec-S EN - Manual (Page 26)

Page 2-26 Rev. 0040807015 1014
Operating Instructions
ARImetec
®
-S
7.0 Functional testing of steam traps
Steam traps can be tested with the structure-borne sound sensor and the surface
temperature sensor.
You must select logarithmic mode in order to test a steam trap with the ARImetec
®
-S .
Refer to section 6.8.6 Check mode" for a description of the possible settings.
Averaging time: 4 s
Mixer frequency: 40 kHz
Check mode: Logarithmic
Temperature and ultrasonic measurements can be taken in parallel. The surface
temperature sensor is rigidly mounted on the testing device housing, so that the device can
be held in one hand and the ultrasonic sensor in the other.
The temperature measurement can be carried out separately if the test points are difficult to
access.
NOTE !
General:
- The multifunctional testing device can only be used to test valves and steam
traps that are operating at the normal working temperature.
Ultrasound:
- Any sound-emitting components in the system under test must be switched off
prior to testing.
- It is important that the ultrasonic sensor should always be positioned at the
same test point on the body of steam traps of the same type, to enable these
steam traps to be compared and any changes ascertained in repeat tests! Refer
to the Operating Instructions for further details.
Steam traps operate on a number of different principles, each with unique
characteristics.
- A steam trap is evaluated using a limit curve. The operating pressure of the
system must be known for this purpose. If the system pressure is not known, it
can also be determined from the steam table below by taking the boiling
temperature. Please read the notes on temperature measurement!
Temperature:
- Since the "ARImetec
®
-S " measures temperatures on the outside of the pipeline
or steam trap, the temperature loss due to heat transfer through the pipe or
steam trap must be taken into account.
As a rough guide: T
(internal)
= T
(external)
x 1.1
- The boiling temperature can be read off from the steam table if the system
pressure is known.
- If the operating pressure of the system is not known, the boiling temperature
can be determined by measuring the surface temperature of the pipeline well
upstream of the steam trap. The test point must be upstream of all sections
where condensate could accumulate and sub-cool.
i