04:13 Nov-21-2007 John O'Brien Consultant, - Chevron ETC , USA, Joined Jan 2000 278
Re: miters in pipeline Your question is incorrect. API 1104 is not a pipeline design code or specification its intent is the control of welding and associated inspection accept/reject criteria.
You need to refer to the pipeline design specification such as B31.4, B31.8, DNV FS 101 or similar. Even if the specification permits the use of miter bends you then need to investigate the long term effects these will have on your ability to perform other actions on your pipeline such as pigging.