Are Your Piping Isometric Drawings Issued for Construction Without Field Welds?
- 20 hours ago
- 2 min read
Do your piping isometric drawings get issued for construction with field welds located, or do you leave that up to the contractor performing the installation?
I started noticing a pattern about ten years ago: engineering firms were issuing piping isometric drawings for construction without identifying field welds. One firm was reprimanded for placing field welds on a project, and management decided to stop locating field welds altogether.
At Turnaround EPC, we believe constructability is key to a practical design and consider off-site fabrication, shipping, and testing with every drawing we issue. If the client plans to pre-fabricate the piping in a controlled shop environment, that matters. If the project needs to pressure-test each piping spool off-site before installation, that, too, must be accounted for.
Our process is to locate field welds and fit-ups during detailed design and collaborate with the installation crew during a constructability review to optimize the field weld locations.
Locating field welds on piping fabrication drawings provides efficiency gains by enabling weld mapping in the office. This allows for a more consistent bid tabulation and fewer surprises because all contractors use the same estimate basis.
Piping connecting to rotating equipment must allow for field-fit-up welds in multiple directions to dial in the precise alignment required on the driver shaft and minimize nozzle loads.
Field welds on pipe spools are required due to shipping dimensional constraints. Replacing field welds with flanges is not recommended due to the increased risk of loss of containment in a bolted flange joint compared with a weld.
Good piping design can make or break a project. If your project is faltering due to poor piping design or sloppy isometrics, we can help.
