Yokogawa RAMC - Manual (Page 124)

<11. INSTRUCTIONS FOR PED>
11-4
IM 01R01B02-00E-E 10th edition January 01, 2013 -00 All Rights Reserved. Copyright © 2003, Rota Yokogawa
Operation reductions:
The operator is responsible, that no corrosion and/or erosion is caused by the medium, which reduces the safety
of the unit as pressure vessel. In addition one has to take care, that no decomposition of unstable fluids may happen.
Corrosion and erosion make the unit fail and can lead to the endangering of persons and facilities. If corrosion and
erosion are possible, this has to be checked by control at the removed unit.
Note
In the following only the dangers, which may appear with the pressure load of the unit, are considered. In
connection with the accompanying electronics additional risks may appear, which requires corresponding
precautions. Also precautions to reach the measuring precision are not considered.
Endangering by: Description Remarks
Surface temperature
Surface temperature is hot in case of high
process temperature. It is the sole
responsibility of the user to stablish
proper means to prevent touching of the
measuring tube.
max. / min. process temperature see chapter 9.3 and 11
max. process pressure
Tightness of the wetted, PED relevant
volume
A factory test is done before delivery
Corrosion and erosion effects
It is the sole responsibility of the
user to select proper wetted materials
for the medium intended to use
(see chapter 11)
Life time evaluation
Experience shows that the lifetime of
the meas uring tube within the
allowed operation conditions is more
than 10 years.
Without erosion and corrosion.
Temperature shock
Permanent temperature cycles of
more than 100°C temp. difference
have to be avoided. Tube failure can
occur because of material wearing.
Medium
Instable fluids
If instable fluids are transported it is
the sole responsibility of the user
that in case of decomposition the
design limits are not exceeded.
Process pressure / temp. relation
Piping and support forces see chapter 2.3 and 3.1
Cho ice of gaskets and pre-stress of the
process connections
It is the sole responsibility of the
user to select suitable gaskets and
to screw the process connections
with the necessary torques.
Refer to EN 1591 -1
Use of closing and openings see chapter 2.3
Pressure shock, water hammer and
pressure surges
Dynamical exceeding of the given
max. pressure at process temp. has
to be avoided.
Water hammer can lead to tube
failures.
Filling and emptying of the pipe work
The measuring tube is part of a pipe
work. The pipe work has to be filled
slowly (see chapter 4.2)
Disposal, cleaning and return see chapter 1.1
Flow direction of the unit upwards
Installation position of the unit see chapter 2.2 and 3.1
A wrong installation position
gives only measuring
disturbances
Installation
Pipe stress by weight of the instrument see chapter 9.4, table 9.6 through
9.10
Permitted ambient conditions
(temperature, humidity)
see chapter 2.2 and 9.3
External fire
External fire can result in
- Rise in pressure by temperature
- Damage of gaskets
It is in the sole responsibility of the
user to implement suitable means to
prevent large damage in the case of
fire.
The instrument itself does not
contain flammable materials.
Outer
influence
Earthquake resistance - Damage of the mounting screws Check by user
see chapter 9.3 and 11
(see chapter 11)
see chapter 11
T111.EPS