Richard BealeIt’s been a long time, but as promised I have feedback for you on the success of the shop fabrication of 1½†and below SW piping. The general consensus from fabrication and construction is that it is working out well, largely due to the fact that the use of 3D CAD for the modelling of these small bore lines produces a high degree of accuracy in the pipe routing.
The negatives are that the fabricators find it a challenge to move it through the shop efficiently due to fit-up time taking longer than welding time, so they have to schedule the small bore with some larger bore to balance the shop activity. No spool fabricator would outright say it, but inference is that if all they were sent were small bore piping orders they wouldn’t be too interested in the work, but provided they have lots of large bore butt weld spools to fabricate to go along with it, they’re happy to accommodate it.
Damage in shipping and handling is more likely than that of large bore spools and consequently there’s invariably some field repair required at site. To reduce this likelihood the maximum spool length that has been adopted is 20ft (6m) as opposed to the more common 40ft (12m) for large bore.
Overall though, it does save time in the field and has proven to be a worthwhile endeavor.