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Reg. 282 b, Reg. 282 c
(b) Limits of cast Iron
Cast Iron shall not be used
for: -
a) |
Temperatures above 220°C; |
b) |
Pressure exceeding 13
bar guage; |
c) |
Valves exceeding 200
mm nominal bore which are connected directly to
the boiler; |
d) |
Wedge or double disc
gate valves which are connected directly to the
boiler; |
e) |
Boiler blow down fittings.
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Explanation: The expression connected directly to
the boiler covers any valve which cannot itself
be isolated from the boiler.
Note:-
Spherodial iron may be used for temperature not exceeding
282 °C and pressure not exceeding 17.58 kg/cm2 provided
it complies with the following requirements in respect
of the physical properties.
(a) 0.2% proof stress 250 kg/mm2
(b) minimum elongation percent-12. |
Reg. 282 c
Limits of copper alloy
Copper alloy shall not be used
for temperatures above 225°C where the valves are
connected directly to the boiler. In the case of valves
not connected directly to the boiler this temperature
limitation may be increased to 260°C. |
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