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pipe It is recommended to remove it after approximately
4 to 8 weeks of operation
4.3 External dryer cartridge
The meter can be equipped with an external silicagel car-
tridge for installation in severe environment conditions To
replace the cartridge, unscrew the old cartridge, remove
the protective plug of the new cartridge and screw it into
the totaliser
4.4 Flow limiters
Flow limiters are recommended to be used to protect the
meter against over-flows or pressure pulses caused by not
perfect installation layout
5 Start-up
5.1 General
The procedure of start-up is always dependent on the in-
stallation configuration
Before pressurising the meter, the lubrication procedure
should be performed Pressurisation or depressurisation
should be carried out with very low pressure change The
pressure change should not exceed 0 3 bar/5 P S I per sec-
ond
After start-up, please check the tightness of the installation
The proper installation and functioning of the meter can
be verified by a visual control of the totaliser (to check that
the meter runs properly) and by measuring its pressure
loss while running though the use of Pete's Plugs may al-
low this pressure loss to be measured while the meter is
pressurised (up to 20 bar)
5.2 Installation with by-pass:
See Annex 5
START-UP:
Begin with all valves closed
• Slowly open the by-pass valve to pressurise the
downstream piping
• When the pressure is balanced downstream, slowly
open the small upstream valve V1 The pressure variati-
on should not exceed 0 3 bar per second
• When the pressure is balanced in the meter, slowly
open the main upstream valve and then close V1
• Slowly open the downstream valve and check that the
meter starts to register the flow
• Gradually, close the by-pass valve Check that the flow
rate doesn't exceed the capacity of the meter
SHUT DOWN:
• Slowly open the by-pass valve and then close the
upstream and downstream valves on the meter line
• Carefully open the small bleeder valve V2 and depres-
surise the meter The pressure variation should not ex-
ceed 0 3 bar per second
• Some gas still inside the meter and the pipe, therefore
sufficient ventilation is required
5.3 Installation without by-pass: See Annex 6
START-UP:
Begin with all valves closed
• Slightly open the upstream valve to pressurise the me-
ter line The pressure variation should not exceed 0 3
bar per second When the pressure is balanced, fully
open the upstream valve
• Slightly open the downstream valve The valve should
be opened a small amount to maintain:
– The upstream pressure in the meter line
– A low flow rate in the meter during the downstream
pressurisation (approx 5% Qmax)
When the downstream pressure is balanced, the down-
stream valve can be completely opened
SHUT DOWN:
• Very slowly close the downstream valve and check that
the meter is no longer recording
• Close the upstream valve
• Slowly open the small bleed valve V2 The pressure vari-
ation should not exceed 0 3 bar per second
• Some gas still inside the meter and the pipe, therefore
sufficient ventilation is required
5.4 Meters placed after a regulator
Installation has to be done in accordance with the techni-
cal manual of the specific regulator During pressurisation
and depressurisation, insure that the pressure variation
should not exceed 0 3 bar per second
7
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