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(a) Material.-All plates, rivets and bars used in
the construction of boilers shall be tested and found to conform
with the Regulations hereinafter contained.
(b) Construction.-
| (i) |
All boilers during construction shall be
under the supervision of an Inspecting Officer and shall
be inspected at all stages of construction prescribed in
Appendix J. Tubes and steampipes shall also be inspected
at the makers’ works at the stages prescribed in
Appendix J, and the tests conducted by the makers shall
also be witnessed by the Inspecting Officer. |
| (ii) |
Welders engaged in site welding of boilers,
steam-pipes, economisers and superheaters shall possess
and produce to the satisfaction of the Chief Inspector
the Welders Performance Qualification Certificate issued
by a Competent Authority. |
(c) Certificates, etc. under section 14(1)(c) of
the Act.-In advance of or along with an application for registration
of a boiler the following certificates and drawings or specifications
shall be furnished to the Chief Inspector, namely:-
| (i) |
A certificate in Form-II.- from an Inspecting
Authority certifying that the material was tested and
the boiler was built under their supervision. Together
with such certificate the Inspecting Authority may furnish
a Memorandum of Inspection Book in Form-I prepared in
the manner prescribed by Regulation 386 in respect of
the Inspection of the boiler during construction and the
hydraulic test applied on completion. In case of a boiler
which is to be assembled only at site, requirement of
the hydraulic test on a completely assembled boiler by
the Inspecting Authority shall not apply provided that
the individual parts of such boiler have been hydraulically
tested and certified by the Inspecting Authority separately
as required under these Regulations.
NOTE.-In lieu of Form-II, a certificate in Form-II-B may
be granted by the Inspecting Authority for boilers for
which variations from the standard conditions in respect
of material, design and construction features have been
permitted by the Board or the Inspection Authority under
sub-regulation (5) or sub-regulation (6) of regulation 3. |
| (ii) |
A certificate in Form-III of manufacture and test
signed by the maker or by a responsible representative
of the maker of the boiler containing a description
of the boiler, its principle dimensions, particulars
of the kind of material used in its construction, the
thickness of all plates, the diameter of and method
of forming the rivet holes in the shell plates, particulars
of any departure from ordinary practice in making the
shell such as solid rolling or welding, the hydraulic
test to which the boiler was subjected, the intended
working pressure, the area of heating surface, the maximum
continuous evaporative capacity, the year and place
of make, and the works number of the boiler.
NOTE.-The Chief Inspector may, however, approve a modified
form of certificate wherein items which do not pertain
to a particular boiler may be omitted.
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(iii)
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A drawing or print to a scale, in the case
of large boilers of not less than ¾ inch to the
foot and, in the case of small boilers of not less than
1 ½ inches to the foot, showing the principal dimensions
and a longitudinal section and end view of the boiler,
and bearing the works number of the boiler and Maker’s
office stamp. The drawing shall show details of riveting
of longitudinal and circumferential seams with pitch of
rivets, cross spacing of dished end plates, fillets and
flanges and corners of bent plates, and where gusset stays
are fitted the number and diameter of rivet holes in each
gusset stay.
In the case of water tube boilers, the foregoing scales
shall apply to the main boiler drums only, but in addition
a general arrangement drawing of the boiler to a scale
of not less than ¼ inch to the foot shall be provided.
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| (iv) |
A certificate in Form-IV from the steel maker and
a certificate from the maker of the plates, rivets or
bars, shall show the charge numbers, the plate or bar
numbers and the number and dimensions of the various
plates etc. tested, their chemical analysis, their ultimate
tensile breaking strength in tons per square inch of
section, the percentage of elongation and the length
on which measured, the number, kind and result of bend
or other tests made and the date of tests:
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Provided that where an Inspecting Authority furnished a certificate
in Form-II together with a Memorandum of Inspection Book in
Form-I in accordance with sub-regulation (c)(i) the certificates
prescribed under clauses (ii) and (iv) need not be furnished
to the Chief Inspector when application is made for registration
of the boiler. But should any question arise in respect of
the fitness of the boilers for the working pressure approved
by the Inspecting Authority within a period of three years
from the date of their registration, the owner shall if requested
by the Chief Inspector obtain and furnish the original documents
specified in the said clauses.
Provided further that in respect of the steel made and tested
by Well-known Steel Makers recognised by the Central Boilers
Board in the manner laid down in regulations 4A to 4H, a certificate
of Well-known Steel Maker in Form-IV-A shall be accepted in
lieu of a certificate from an Inspecting Authority:
Provided also that in respect of the tubes/pipes made and
tested by Well-known tube/pipe maker recognised by the Central
Boilers Board in the manner as laid down in regulations 4A
to 4H, a certificate of manufacture and test of Well-known
tube/pipe maker in Form-III-D or III-E, as the case may be,
shall be accepted in lieu of a certificate from an Inspecting
Authority.
In case where certificate in Form-IV is not producible owing
to such certificate containing details of plates used for
other purpose, also, all the relevant information in respect
of the boiler furnished in Form IV-A duly signed by the Makers
of the boiler and countersigned by the Inspecting Authority,
shall be acceptable in lieu of the certificate in Form-IV.
Original steel maker’s certificate or manufacture and
results of tests shall be produced to the Chief Inspector
on demand.
In the case of fusion welded drums the diagram of welded repairs
and temperature charts of heat-treatment shall also be furnished.
In addition, certificates in respect of yield point at service
temperature (0.2 per cent proof stress), the average stress
to produce elongation of 1 per cent (creep) in 100,000 hours
and the average and the lowest stresses to produce rupture
in 100,000 hours in the material, wherever is applicable,
are to be furnished.
| (vi) |
For tubes and pipes subjected to internal pressure,
a certificate giving results of tests regarding chemical
analysis, warm yield point (0.2 per cent proof stress),
the average stress to produce an elongation of 1 per
cent (creep) in 100,000 hours and the average and the
lowest stresses to produce rupture in 100,000 hours
in the material wherever applicable, shall be furnished.
NOTE:-
Until 33,000 hours tests are carried out by National
Metallurgical Laboratory or Corporate Research and
Development Laboratory of Bharat Heavy Electricals
Limited for collecting elevated temperature data of
alloy steel produced indigenously against ASME or BS or
EN Code, these grades of steel may be accepted and long
time elevated temperature properties/maximum allowable
stress values given in ASME or BS or EN Code, as the
case may be, may be used for the purpose of design.
Provided that
(I)
a certificate is furnished by the producer of the
steel to the effect that the steel has been manufactured
strictly in accordance with the technical requirements
of the ASME or BS or EN Code to assure that the creep
rupture requirements are complied with.
(II)
the Steel maker furnishes the necessary certificate that
the steel conforms to the chemical analysis, room and
elevated temperature mechanical properties given in ASME
or BS or EN Code as the case may be.
(III)
the short-term stress-rupture tests for 1000
hours as described below are carried out by NML/Steel
Plants for the purpose of checking whether the steel is
up to the specification and also to ensure that the
Steel is capable of meeting the long-term rupture stress
values/ maximum allowable stress values given in ASME or
BS or EN Code, as the case may be, and a certificate is
given by NML/Steel plant to this effect.
(IV)
two numbers of 1000 hour creep rupture tests
shall be carried out at a temperature 50°C
above the service temperature for each grade of steel
for tubing or piping or castings or plates grades; when
in furnace and/or in superheater zone.
However, the forging to be used in valves should
be tested at 550°C
for 1000 hours.
The stress to cause rupture in 1000 hours at
above temperatures may be taken from the master curve
corresponding to –20% line.
At this stress, a minimum rupture life of 1000
hours is expected.
Both the samples should pass 1000 hour tests at
the above stress and temperature.
These samples may be selected at random by the
Chief Inspector of Boilers of the respective State.
The samples could be in the form of semi-finished
products, say, forged bars of about 25mm2
which will undergo heat treatment as prescribed by the
relevant specifications.
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(d) Maker’s Stamp.- The boiler shall have stamped
upon its front plate in a conspicuous position the following
particulars:-
| MAKER’S NAME |
Works’ Number_____________________________________
Year of make__________________ Tested to __________________________
Lbs.________________________ on _______________ W.P.________________________________________________
Lbs._____________
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Inspecting Officer’s or
Inspecting Authority’s Official
Stamp
___________________________________
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(e) Certificates for steam-pipes – A certificate
of manufacture and test in Form III-A, signed by the maker and
the Inspecting Authority shall be furnished.
(f) Certificates for tubes – A certificate of manufacture
and test in Form III-B, signed by the maker and the Inspecting
Authority shall be furnished.
Note: In case of tubes made by Well-known Tube Makers recognised
by the Central Boilers Board in the manner as laid down in regulations
4A to 4H in India or other countries, material testing including
mechanical tests may be carried out by them and the particulars
regarding testing of material including mechanical tests as
certified by them shall be noted in the appropriate column or
paragraphs in the certificate in Form III-B. In case, certificate
from the “Well-known Tube Makers” as aforesaid, is
produced, such certificate may be accepted in lieu of the certificate
from the Inspecting Authority in so far as it relates to testing
of material including mechanical tests specified in this form.
(g) Certificates for mountings and fittings:- A certificate
of Manufacture and Test in Form III-C signed by the Maker and
the Inspecting Authority in respect of boiler mountings and
steam-pipe fittings during manufacture, shall be furnished.
Note-1: For the purpose of this clause certificates issued by
an authority empowered in this behalf by or under the law in
force or the national code in a foreign country, in respect
of mountings and fittings in that country and containing the
particulars required to be specified in this certificate, may
be accepted. Where, however, the material used, is in conformity
with the code of the country of manufacture and is covered by
those Regulations, the permissible stress figures specified
in the Code at different temperatures may be accepted in lieu
of figures computed from the data required to be furnished under
Regulation 271 in any of the following cases, namely:-
| (i) |
Where a certificate is furnished from an
Inspecting Authority to the effect that the steel complies
with the requirements of the grade steel (to be specified)
and the permissible stress for the working conditions
as allowed for in the Code of the country of manufacture
falls within the limit permissible under this Regulation. |
| (ii) |
Where the basis upon which these stresses
have been arrived at is made available and such basis
is not found to be such as to give rise to stresses higher
than those permissible under the Regulations. |
Note-2: For the purpose of clause (c), (e), (f) and (g) of this
regulation, certificates issued by an authority empowered in
this behalf by or under the law in force or national Code or
Standard of any foreign country in respect of plates, bars,
tubes, pipes, forgings and castings manufactured in that country
and containing the particulars required to be specified in the
steel makers certificates referred to in the above mentioned
clauses of regulation 4 may be accepted provided such certificates
contain a statement duly signed by the Inspecting Authority
to the effect that these materials comply with the requirements
of the law or the Code or Standard of the foreign country.
Note-3: Photostat copy of the certificate in Form III-C shall
be accepted provided it is endorsed by the manufacturer or the
Inspecting Authority.
(h) Certificates of inspection during construction of pipes
for which variation from standard conditions have been permitted.-
A certificate of manufacture and test in Form III-A(I), signed
by the maker and the Inspecting Authority shall be furnished.
(i) Certificate of Inspection during construction of tubes
for which variation from standard conditions have been permitted.-
A certificate of manufacture and test in Form III-B(i), signed
by the maker and the Inspecting Authority shall be furnished.
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