Gas Feed System At Average Pressure (A Few Bars) - baltur COMIST 36 Instrucciones

GAS FEED SYSTEM AT
AVERAGE PRESSURE (a few
bars)
(see BT 8058 - BT 8530/1 - BT
8531/1)
When high delivery is required, the
Gas Distributing Company requests
the installation of a unit comprising
a pressure reducer and a meter,
and then connects it to the gas pipe
network at average pressure (a few
bars).
This unit can be supplied by the
Gas Distributing Company or by
the user, but should be according to
the Gas Company's precise instruc-
tions.The unit's pressure reducer
should be large enough to supply
the maximum gas delivery required
by the burner at the rate of pressure
normally estimated for it.
From experience, we would recom-
mend utilising a large-scale reducer
in order to attenuate the notable
increase in pressure which occurs
DIAGRAM FOR CALCULATING THE DIAMETER OF THE PIPES IN RELATION
TO THEIR LENGTH AND GAS FLOW
PRESSURE DROP IN mm OF H
when the burner comes to a stand-
still, with a high delivery.
(Regulations require that the gas
valves close in less than one se-
cond).
As an indication, we would advise
using a reducer capable of produ-
3
cing a delivery (m /h) about double
that of the maximum amount esti-
mated for the burner.
If several burners are to be used,
each one should have its own pres-
sure reducer; this will enable the
gas feed pressure to the burner to
be maintained at a constant level
even if only one burner is operating
at the time.
Consequently, it is possible to ac-
curately regulate the delivery and
therefore the combustion, and thus
improve yield.The dimension of the
gas pipeline should be in function
with the quantity of gas it has to deli-
ver. We advise maintaining the load
loss at a low level (not more than 10
% of the gas pressure value at the
burner); it should be kept in mind
FLOW IN m c /h OF METHANE p.a. 0,60
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that the load loss is added to the
pressure existing when the burner
stops and therefore a subsequent
start up will occur at a pressure that
rises in accordance with an increase
in the pipe's load loss.
Should the gas pressure reach
unacceptable values when the
burner stops (rapid closure of the
gas valves), it is necessary to install
between the reducer and the first val-
ve of the burner an automatic over-
flow valve and relative conveying
pipe, of suitable section, in the open
air. The end of the conveying pipe
in the open air should terminate in
a suitable place, be protected from
rain and have a flame trap.
The overflow valve should be regu-
lated in such a way as to completely
unload excessive pressure.
See diagram n° BT 8058 for gas
pipeline dimensions. Near to the
burner should also be fitted a cut-off
ball cock, a gas filter, an anti-vibra-
tion joint and a flanged fitting (see
BT 8530/1 and BT 8531/1 ).
DIAMETER OF PIPES IN INCHES
N° BT 8058