New York Codes, Rules and Regulations › Title 12 - DEPARTMENT OF LABOR › Chapter I - Industrial Board Of Appeals › Subchapter A - The Industrial Code › Part 14 - Construction, Installation, Inspection And Maintenance Of High Pressure Boilers; Construction Of Unfired Pressure Vessels › Subpart 14-3 - Repairs, Alterations And Miscellaneous Requirements › Welded Repairs and Alterations › Section 14-3.8 - Welding repairs of cracks

Current through Register Vol. 46, No. 28, July 10, 2024
(a)
						Removal of defects. A repair of a defect, such as a crack in a welded joint or
						base material, may not be made until the defect has been removed. A suitable
						nondestructive examination method shall be used to assure complete removal of
						the defect. If the defect penetrates the full thickness of the material, the
						repair shall be made with a complete penetration weld such as a double butt
						weld or a single butt weld with or without backing.
Note: Before repairing a cracked area, care should be
						  taken to investigate its cause and to determine its extent. Where circumstances
						  indicate that the crack is likely to recur, consideration should be given to
						  removing the cracked area and installing a patch or other corrective
						  measures.
(b) Cracks in
						unstayed areas. Cracks in unstayed shells, drums or headers of boilers may be
						repaired by welding, provided the cracks do not extend between rivet holes in a
						longitudinal seam or parallel to a rivet seam within eight inches, measured
						from the nearest caulking edge. The total length may be welded, provided the
						complete repair is radiographed and stress relieved in accordance with section
						14-3.15 
						of this Subpart. Cracks in unstayed areas shall be repaired as specified in
						figure 14-3.8(2) or by other equivalent methods.
(c) Cracks in unstayed furnaces. Cracks of
						any length in unstayed boiler furnaces may be welded provided the welds are
						thermally stress relieved in accordance with section
						14-3.15 
						of this Subpart. Welds applied from one side only shall be subject to the
						approval of the inspector. Field repair of cracks at the knuckle or the turn of
						the flange of the furnace opening require immediate replacement of the affected
						area. See Figure 14-3.8 (1) which follows:
FIGURE 14-3.8(1)--UNSTAYED BOILER FURNACES
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(d) Cracks between tube holes in water-tube
						boiler drums or in wrought or cast steel (but not cast iron) sectional headers
						may be repaired by welding, provided the plate thickness does not exceed one
						inch and further provided that there are no more than two such cracks in any
						one row in any direction, nor more than a total of four such cracks in any one
						drum or header. The tubes on each side of a cracked ligament shall be removed
						before any welding is done, and after the welding is completed, the tube holes
						shall be reamed or otherwise properly prepared for reinstallation of the
						tubes.
(e) Cracks in plain
						circular, corrugated, Adamson ring or similar type furnaces may be repaired by
						welding, provided they are locally stress relieved as required by section
						14-3.15 
						of this Subpart.
(f) Cracks in the
						flat portion of tube sheets adjacent to furnaces in Scotch marine boilers
						require immediate replacement of the affected area.
(g) Prior to repairing a crack between tube
						holes in a boiler, the tubes at each end of the crack shall be removed and, if
						considered necessary by the inspector, additional tubes shall be removed. When
						the welding is completed, the tube holes shall be reamed or otherwise properly
						prepared for reinstallation of the tubes.
(h) Circumferential cracks in the knuckle or
						turn of a flange of a furnace or flue opening or adjacent to a manhole opening
						of an unstayed head require immediate replacement of the affected area.
FIGURE 14-3.8(2)--RIVET AND STAYBOLD HOLE CRACKS
Image
(i) Cracks radiating from rivet or staybolt
						holes may be repaired if the plate is not seriously damaged. If the plate is
						seriously damaged, it shall be replaced. The repair method shall be as follows:
(1) Prior to welding, the rivets or staybolts
						from which the cracks extend and the adjacent rivets or staybolts shall be
						removed.
(2) In riveted joints,
						tack bolts shall be replaced in alternate holes to hold the plate laps
						firmly.
(3) The cracks shall then
						be prepared for welding by chipping, grinding or gouging.
(4) In riveted joints, cracks which extend
						past the inner edge of the plate lap shall be welded from both sides.
(5) Rivet holes shall be reamed before new
						rivets are driven.
(6) Threaded
						staybolt holes shall be retapped and new staybolts properly driven and
						headed.