Keep this manual easily accessible for all users
Ask for a written approval of the manufacturer for all cas-
es not planned in this instruction manual Please respect
all national rules for installation, operation and service of
gas meters
1 Characteristics
Delta meters are designed to measure gases of the 1st,
2nd and 3rd gas families as specified in EN437 as well
as various filtered and non-corrosive gases (e g Oxygen)
2 Packing
• The meter, depending on the size or version is deliv-
ered:
• In a cardboard box, protected by carton inserts or poly-
ethylene wedges
On a wood pallet, protected by a cardboard cover
The packing shall contain the filling lubricant, plugs for the
installed transmitters and this instruction manual
2.1 Storage
If the meter is not going to be used immediately, it should
be stored under cover in a clean, dry environment, in the
horizontal position
The caps fitted in the inlet and outlet pipe must stay in
place until installation
2.2 Handling
The meter is delivered without lubricant in covers Before
shipping or handling, ensure that the lubricant has been
thoroughly drained from the front and the rear covers
to prevent spillage into the measuring chamber Meters
should be lifted only with belt around the main body or
with the eyelets
3 Installation
3.1 General
Due to the volumetric principle of the Delta meter, its
metrology is not influenced by the installation conditions
Nevertheless the respect of the following rules will insure
the best use of your Delta meter:
Recommended installation: See Annex 1
• Check visually that the meter has not been damaged
during transport
• No welding is allowed with meter installed
• The meter should be installed with the impellers hori-
zontal Allowed deviation: +/- 5°
• Never install a meter at a low point in the piping where
the meter could be subject to the accumulation of wa-
ter or particles
• If Teflon tape is used to tight threaded joint then the
best attention must be taken to avoid introducing tape
in the measuring chamber
• The meter should be installed without stress in the pip-
ing The flanges must be correctly lined up
• The meter should be considered in a possible ground-
ing system
• On flanges with UNC screw-thread, the threads are
NOT metric but defined in inch following ANSI/ASME
B1 1 – 1989
4
Metric threads and threads defined in inch are not
compatible!
• Please tighten bolts in opposite pairs
• A flexible coupling can be used to ensure a stress-free
installation
• The use of a filter, placed upstream of the meter, is ad-
visable in gas with high particulate content See § 3 2
Before installation:
• The piping upstream of the meter should be free of
dust
• Remove the protective caps
• Ensure that the direction of gas flow corresponds with
the arrow situated on the meter body
• Check that the impellers turn freely
• Possible accessories to be assembled onto the meter
must not interfere its corrosion protection
• When mounting the meter, the maximum torque ac-
cording to the table in Appendix 1 must be taken into
account For meters where the recommended torque
is 100 Nm, first tighten all screws to 70 Nm before
tightening to 100 Nm Each fastening step must be
crosswise around the flange
3.2 Filtration
Rotary meters work better if there are no particles within
the gas It is advisable therefore to filter the gas upstream
of the meter Recommended level of filtration is 100 μm
or better
While the meter is in service, periodically check the
cleanliness of the filter, especially in the case of a new
installation or after work has been performed on the up-
stream piping
For installation with flow direction from bottom to top a
particular attention has to be taken to the filtering condi-
tions to avoid that accumulation of dust downstream of
the meter may come back into the meter For example
a second filter can be installed downstream of the meter
3.3 Lubrication
3.3.1 General
Choose the lubricant according to the operating condi-
tions This lubricant should be neutral and non detergent
Important:
• A lack of lubricant could cause premature wear of the
meter
• An excess of lubricant can also induce problems A
surplus of lubricant can contaminate the measuring
chamber, may degrade the metrology and cause dam-
age to the bearings and the impellers due to the mix-
ture of lubricant and small impurities contained in the
gas
• Always drain the end-covers before moving the meter
3.3.2 Choice of lubricant
Viscosity: The viscosity has been calculated to ensure
mechanical and metrological performance of the meter
Commercial references: Annex 2 contains a list of com-
mercial lubricants usable for industrial gas except gases
such oxygen and halogens For other gases, please con-
sult us