(2)In the case of cylinders having welded or brazed seam, repairing of minor defects, such as small weld cracks, pin holes, blow holes, undercuts in welding, leaks at the weld (shown in periodical hydrostatic test) may be allowed provided-(a)the defects have been removed by grinding, chipping, gouging or other approved methods;(b)the repairing is carried out by a certified welder at the premises of a manufacturer of cylinders recognised by the Chief Controller under the supervision of a competent person by-(i)welding, if the original seams were welded;(ii)brazing, if the original seams were brazed;(c)the cylinder is properly heat-treated after the repairs;(d)the welded or brazed seams of the cylinder are radiographed if the cylinder was originally required to be radiographed after its manufacture;(e)after repairs and heat-treatment, the cylinder is subjected to the same pneumatic and hydrostatic test or hydrostatic stretch test as was done at the time of manufacture.
