Start-Up; General; Installation With By-Pass: See; Installation Without By-Pass: See - ITRON Quantometer Delta QD Mode D'emploi

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5 Start-up

5.1 General

The procedure of start-up is always dependent on
the installation 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 second .
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 allow this
pressure loss to be measured while the meter is
pressurised (up to 20 bar) .
5.2 Installation with by-pass:
See Annex 6
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 variation 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
depressurise the meter . The pressure variation
should not exceed 0 . 3 bar per second .
• Some gas still inside the meter and the pipe,
therefore sufficient ventilation is required .
6

5.3 Installation without by-pass: See

Annex 7
START-UP:
Begin with all valves closed .
• Slightly open the upstream valve to pressurise
the meter line . The pressure variation should
not exceed 0 . 3 bar per second . When the pres-
sure 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
downstream 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 pres-
sure variation 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
technical manual of the specific regulator . During
pressurisation and depressurisation, insure that
the pressure variation should not exceed 0 . 3 bar
per second .

6 Maintenance

6.1 Maintenance of the meter

Once installed, the meter does not require any
specific attention except a periodical check or
change of the lubricant filled in the covers .
After start-up:
Natural gas: After the preliminary term of service,
the lubricant level should be checked .
Other gases: After a working period of 100 hours
from commissioning, the lubricant level should be
checked .
If the lubricant level is appreciably low, if the lubri-
cant is emulsified or if there is a chemical reaction
between the lubricant and the gas, the lubricant

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