Basics for installing the device in a pipe
HON 512 with HON 650 pilot user manual
41
Depending on the specific system design, the L
uR
lengths of the undisturbed pipes down-
stream of the sensing point must be (1.5
to
4)
x
DN of the pipe:
Undisturbed length of pipe
for
L
uR
min.
1.5
x
DN
Thermowells
L
uR
min.
1.5
x
DN
Reducers and expanders, depending on the
specific system conditions
L
uR
min.
3
x
DN
Shut-off devices (gate valves, check valves, and
reduced bore ball valves)
L
uR
min.
4
x
DN
Tees
▪
Shut-off devices with an undisturbed flow pattern (such as full bore ball valves) and, if
applicable, pipe bends (depending on the design) are considered to be non-disturbing
elements in terms of measuring impulse line connections.
▪
For gas meters (turbine gas meters including quantometers, ultrasonic gas meters, and
vortex flow meters, but NOT rotary piston gas meters), there are no restrictions in terms
of measuring impulse line configurations, as these meters are not considered to be
flow-disturbing within this context.
▪
The following applies to rotary piston gas meters: Minimum distance between gas
pressure regulator or reducer / expander and gas meter:
L
uR
min.
3
x
DN
.
▪
Measuring impulse line connections downstream of gas meters must be at a distance of
L
uR
min.
2
x
DN
.
▪
If shut-off valves are used (reduced bore), the recommended distance downstream of a
measuring impulse line is
L
uR
min. 3 x DN
.
▪
Gas meter pressure losses must be taken into account based on system conditions if
applicable.
Downstream of the
sensing point
Details
Summary of Contents for HON 512
Page 185: ...Appendix HON 512 with HON 650 pilot user manual 185 X Fail to open version Y Amplifying valve ...
Page 205: ...Appendix HON 512 with HON 650 pilot user manual 205 ...
Page 206: ...Appendix HON 512 with HON 650 pilot user manual 206 ...
Page 207: ...Appendix HON 512 with HON 650 pilot user manual 207 ...
