Welding heating and cutting 744 1 welding shall be

Welding,
Heating and
Cutting
7.44 (1) Welding shall be carried out by welders who possess a
valid welding certificate for the appropriate category of
welding.
(2) Pre-setting, pre-bending, skip welding, back-step
techniques and other measures shall be taken as
necessary to counteract shrinkage or distortion due to
welding, gouging, thermal cutting or heat treatment.
(3) Butt welds shall be complete penetration butt welds
made between fusion faces.
(4) Butt welds in each component part shall be completed
before the final assembly of built-up assemblies.

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(5) Welding of austenitic stainless steel shall be carried
out in accordance with BS4677. Notwithstanding this,
welding of stainless steel members other than pipes
shall comply with BS EN 1011-3. All heat tints shall
be removed and the Contractor shall propose a
method of removal of any heat tint resulting from
welding for the approval of the Engineer.
(6) Temporary welded attachments shall not be used
unless approved by the Engineer. Temporary
attachments shall be removed by cutting which leaves
a remnant at least 3mm proud of the surface. The
remnant shall be removed by grinding flush. The area
shall be tested by Magnetic Particle testing to BS EN
ISO 9934-1.
(7) Welding, heating or thermal cutting processes which
give off toxic or irritant gases shall not be used unless
permitted by the Engineer; if permitted, precautions,
including the provision of exhaust ventilation, breathing
apparatus and display of warning signs, shall be taken
to enable the work to be carried out in safe conditions.
Welding heating or thermal cutting shall not be carried
out within 2 m of lead based, cadmium or
carbonaceous coatings.
(8) Welding shall be carried out only under the direction of
an experienced and competent supervisor. A record
shall be kept to enable welds to be identified with the
welders responsible for the work, but finished work
shall not be marked by hard stamping for this purpose.
(9) All welds which are removed shall be tested by
Magnetic Particle testing to BS EN ISO 9934-1, shall
be carried out before any subsequent re-welding. All
weld repairs shall be subject 100% non-destructive
testing.
Length of Bolts 7.45 The length of HSFG bolts shall comply with BS 4604:Part 1,
or BS 4604: Part 2 as appropriate. The length of bolts
complying with BS 3692, BS 4190 and BS 4933 shall be
such that the end of the bolt will project above the nut by at
least one thread, but by not more than one nominal bolt
diameter, after tightening.
Length of Threads 7.46 The length of threads on bolts shall be determined in
accordance with BS 3692, BS 4190, BS EN 14399 or BS
4933 as appropriate. If additional locknuts or other nuts

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are specified, the thread length shall be increased by one
nominal bolt diameter for each additional nut.