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Reg. 525
STANDARD CONDITIONS FOR THE DESIGN AND
CONSTRUCTION
OF ECONOMISER, FEED PIPES, FEED HEATERS AND OTHER SIMILAR
VESSELS
REGULATIONS FOR REGISTRATION AND INSPECTION OF ECONOMISERS
AND FEED PIPES
Procedure for Registration |
| b) |
The fitness of the economiser parts shall be determined
as per the following formulae:-
| (iii) |
Headers of approximately circular cross-section
| WP
= |
0.6K(t-5) |
Eqn. (126) |
| D |
Where,
t = Thickness in thirty-seconds of an inch.
WP = Design pressure, in pounds per square inch
)gauge).
D = Outside diameter of header in inches.
K = 265 for Grade 16.5 Iron.
= 240 for Grade 14 Iron.
= 220 for Grade 12 Iron.
The minimum thickness of plain cylindrical portions
of a header in that part of the length which does
not contain tube holes shall comply with the requirements
of sub-clause (v).
In no case, however, shall the thickness at any
point may be less than 16 thirty-seconds of an inch. |
| (iv) |
Tubes
Where,
t = Thickness in thirty-seconds of an inch.
WP = Design pressure, in pounds per square inch
)gauge).
D = Outside diameter of header in inches.
K = 265 for Grade 16.5 Iron.
= 240 for Grade 14 Iron.
= 220 for Grade 12 Iron.
C = 4 for portion where gills act as reinforcement.
= 5 for portion not reinforced.
In no case, however, shall the thickness at any
point may be less than 11 thirty-seconds of an inch. |
| (v) |
Manifold
Pipes
| WP
= |
0.8K(t-5) |
Eqn.
(126) |
| D |
Where,
t = Thickness in thirty-seconds of an inch.
WP= Design pressure, in pounds per square inch
)gauge).
D = Outside diameter of header in inches.
K = 265 for Grade 16.5 Iron.
= 240 for Grade 14 Iron.
= 220 for Grade 12 Iron.
In no case, however, shall the thickness of a manifold
pipe or branch be less than 14 thirty-seconds of
an inch. |
| (vi) |
Cast Iron
Economisers with extended surface horizontal tubes,
Connector Bends
Where,
t = Thickness in thirty-seconds of an inch.
WP= Design pressure, in pounds per square inch
)gauge).
D = Outside diameter of header in inches.
K = 265 for Grade 16.5 Iron.
= 240 for Grade 14 Iron.
= 220 for Grade 12 Iron.
“In no case, however, shall the thickness of
a connector bend be less than 10.3 mm (13 thirty-seconds
of an inch) for 18.75 kg/cm² ( 12.0 tons sq.
in.) and 22.00 kg/cm², (14.0 tons/sq. in.)
grade irons and 9.0 mm (11 thirty-seconds of an
inch), for 26.00 kg/cm² (16.5 tons/sq. in.)
grade iron.”
Tubes.
To comply with equation (127).
Manifold Pipes
To comply with equation (128).
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| c) |
The Inspector shall
enter full particulars of the economisers together with
the required calculations of various parts in a Memorandum
of the Inspection Book (Form IX) and submit it to the
Chief Inspector. |
| d) |
If no formula or co-efficient
applicable to any part, other than what is mentioned above,
is contained in the Regulations, the Chief Inspector shall
at his discretion determine the fitness of the part. |
| e) |
After Inspecting the
Economiser and ascertaining, as prescribed, the maximum
working pressure to which it may be worked, the Inspector
shall witness the hydraulic test in accordance with Regulation
No. 527 and may issue a Provisional Order in Form X. |
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