BERTHOLD TECHNOLOGIES LB 3602, Руководство по эксплуатации

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LB 379
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e) The pipeline must not be subject to heavy vibrations as this could damage the de-
tector. Vibration dampers have to be installed, if necessary.
f) Samples have to be taken for calibration of the measurement. A sampling point has
to be provided in the direct vicinity of the measuring site.
2.1.3 Installation Instructions for PTFE lined Measuring
Paths (LB 379)
Lined parts must not be welded, soldered or burned as this can destroy the plastic material.
The flanges of all parts are provided with protective plates, so that the sealing surfaces are
not damaged during transport and storage. The protective plates should not be removed
until immediately before installation. If plates are taken off for control purposes, they have
to be attached again in any case.
No further seals are required between the sealing surfaces; however, possibly when at-
taching a sealing surface to a flange made of metal, glass, carbon or ceramic, if that flange
is not plane-parallel. This PTFE seal, which should be about 5 mm thick, can then absorb
tensions and inhomogeneities as a resilient sealing element.
The screws should be tightened to a torque of 45 Nm. The sealing surface may get de-
formed if the screws are tightened too much during installation of pipe parts.
During commissioning of a line system the flange screws should be retightened once more
to the specified torque after reaching the final temperature.
Pipeline parts may be disassembled only at max. 40°C so that the sealing surfaces are not
damaged.
If a flange connection leaks, although all screws are tightened, NO LONGER TIGHTEN but
loosen the screws on the side opposite the leak and tighten the other side. If the leak
persists, examine the sealing surfaces for grooves or chips which may be the cause of the
leak. If the impressions or damage are no deeper than about 15% of the flange thickness,
these can be removed with fine emery cloth.
2.1.4 Installation of the Resistance Thermometer Pt 100
A temperature measurement must be carried out such that the measured temperature is
fairly equal to the product temperature at the density measuring site. The resistance ther-
mometer must not obstruct the path of radiation.
If the resistance thermometer cannot be installed in the pipeline, it may also be mounted
on the outside of the pipeline.
The pipeline with the mounted resistance thermometer must be provided with temperature
insulation over a length of 1 - 2 m to ensure that the surface temperature of the pipeline
at the temperature measuring point is fairly equal to the product temperature. Neverthe-
less, it may happen, especially with plastic pipes or lined pipelines that very rapid temper-
ature changes occur in the product to be measured will lead to temperature-induced
measurement errors. The change in density is detected by the measurement without time
delay; however, the necessary temperature correction is delayed due to the inertia of the
temperature measurement. This influence can be reduced by operating the measuring de-
vice with the greatest possible time constant.