5.2.1 Preheating
is to be effected by a method which ensures uniformity of temperature
at the joint. The method of heating and the means adopted for temperature
control are to be to the satisfaction of the Surveyors.
5.2.2 All
welding is to be performed in accordance with the approved welding
procedures in this Section by welders who are qualified for the materials,
joint types and welding processes employed.
5.2.3 Welding
without filler metal is generally not permitted for welding of duplex
stainless steel materials.
5.2.4 All
welds in high pressure and high temperature pipelines are to have
a smooth surface finish and even contour; if necessary, they are to
be made smooth by grinding.
5.2.5 Check
tests of the quality of the welding are to be carried out periodically
at the discretion of the Surveyors.