Alstom FKG1X, Инструкция по эксплуатации

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GRID
High Voltage Switchgear
PS 0004EN 03 G. BERNARD
1998-08-12
J . VIAT
2011-03-21
1 / 3
Sheet N° Revision Written by Date Signature Approved by Date Signature Page
SAFETY SHEET
SF6
Use and Handling
CAUSE OR ORIGIN OF HAZARD .
Sulphur hexafluoride (SF
6
) is a ga s whic h in its ba sic state is colourless, od ourless and ta steless. It is
not toxic, but it cannot sustain life. It is a hea vy gas that is dispersed slowly into the atmosphere.
In its natural state, SF
6
is delivered and stored in pressurized tanks (bottles or spheres) at a pressure
of a pp roximately 20 bar at 20°C (in its liquid form) and complies with IEC stand ard 376.
However, under the effect of the electric arc, the SF
6
molecules break up and the elements mostly
recombine during cooling either due to extinction of the arc or by regeneration caused by the
presenc e o f active a bsorbent charges within the c ircuit brea ker.
Various chemical reactions, associated with the volatilization of the materials in contact with the
electric arc, create either fluoridized or sulphurous secondary gas products or solid products in the
form of metallic fluoride powder ; or again, in the presence of traces of water or moisture,
hydrofluoric acid or sulphur dioxide.
In the life-cycle o f the equipment, SF
6
can be observed not only in its pure state, but also in its
contaminated state :
- the use of new SF
6
for filling or adding,
- leaks unde r normal op erating cond itions,
- maintenanc e involving the ope ning of circuit breakers containing old SF
6
(decomposition
products),
- ab normal conditions (internal arc fault causing the shielding to brea k),
- circuit breaker rec ycling on end of life-cycle.
WORK REQUIREMENTS.
Follow the instruc tions for the transpo rt of pressurized c ontainers.
The storag e of these containers is governed by the same storage regulations as compressed gas
bo ttles :
- keep awa y from any source of heat and in a cool, dry and well-ventilated area ,
-
always fit a pressure reducing valve.