[Code of Federal Regulations] [Title 46, Volume 2] [Revised as of October 1, 2004] From the U.S. Government Printing Office via GPO Access [CITE: 46CFR52.01-100] [Page 128-129] TITLE 46--SHIPPING CHAPTER I--COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PART 52_POWER BOILERS--Table of Contents Subpart 52.01_General Requirements Sec. 52.01-100 Openings and compensation (modifies PG-32 through PG-39, PG-42 through PG-55). (a) The rules for openings and compensation shall be as indicated in PG-32 through PG-55 of the ASME Code except as noted otherwise in this section. (b) (Modifies PG-39.) Pipe and nozzle necks shall be attached to vessel walls as indicated in PG-39 except that threaded connections shall not be used under any of the following conditions: (1) Pressures greater than 4137 kPa (600 psig); (2) Nominal diameters greater than 51mm (2 in.); or (3) Nominal diameters greater than 19mm (0.75 in.) and pressures above 1034 kPa (150 psig). [[Page 129]] (c) (Modifies PG-42). Butt welding flanges and fittings must be used when full radiography is required by Sec. 56.95-10. [CGD 81-79, 50 FR 9432, Mar. 8, 1985]