[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: 46CFR59.10-15] [Page 284] TITLE 46--SHIPPING CHAPTER I--COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PART 59_REPAIRS TO BOILERS, PRESSURE VESSELS AND APPURTENANCES--Table of Contents Subpart 59.10_Welding Repairs to Boilers and Pressure Vessels in Service Sec. 59.10-15 Rivets and staybolts. (a) It is not permitted to reinforce or build up by welding the heads of rivets or staybolts that have deteriorated. Such rivets or staybolts shall be replaced. The seal welding of rivet heads to secure tightness is prohibited. (b) Where leaks develop around staybolts which are otherwise in good condition, the nuts may be replaced with a beveled collar formed around the end of the stay by means of welding. In such cases, the depth of collar measured on the stay and the width measured on the plate, shall be equal to one-half the diameter of the staybolt.