Fabrication: Spool fabrication follows the design criteria of the project. Producing precise spools with the required material is a given for each project, but how the materials, pipe, etc. are inspected, prepared, preserved, and stored makes all the difference in starting the project out on a positive note.
Steel Segregation: Carbon steel fabrication and stainless-steel fabrication preferably takes place in two different shops. In fabrication shops with carbon steel and stainless-steel lines, segregation of materials and tools such as grinders and clamps is required. Color coding of tools such as clamps and grinding discs is standard practice to ensure tools used during carbon steel fabrication are not used in stainless-steel fabrication. Tools used in carbon steel applications are normally marks in red, and tools used in stainless steel applications are normally marked in blue. Fire blankets should be used to ensure grinding sparks from carbon steel preparation do not come in contact with stainless steel spools and components.
Flange Storage: Loose flanges should be stacked with timbers placed across the bolt hole and not across the raised face…resins in finished wood can actually causes pitting of flange faces over time.
Flange Inspection: Inspecting loose flanges before welding them onto a spool is a good idea. Just because new loose flanges are available to weld to a spool, does not mean the flange face meets B16.5/B16.47 or PCC1 acceptance criteria. Flanges should be inspected for pitting, mechanical damage, etc. and segregated into a “rejected” hold area when additional flanges were purchased for the project. If the viable flanges meeting PCC1/B16.5/B16.47 criteria are not available, the flanges should be marked/tagged with identification letting the end user know rectification efforts are required before final bolting can be performed. Flanges in the 150# class should be handles with care as a minimal amount of material can be removed during flange refacing and still retain pressure rating.
Flange Installation: Flanges are often turned face down for bevel preparation during installation. Protective covering such as flangeMAGS, flangeRINGS, or flangeDOTS are necessary to ensure the flange face is not damaged during the fit-up/installation process.
RT: Commination/coordination with NDT personnel is critical for spools with flanged/un-flanged openings. Spools which have an RT requirement often have protective covers removed. Protective covers should be re-installed as soon as NDT is complete. NDT is normally performed at night…frustration abounds when dayshift personnel arrive to find protective covers laying on the ground after a few hours of rain overnight.
Storage: Completed spools should be place on dunnage 4-6” from grade. Un-flanged spools should be clean and have UV resistant covers installed on beveled end held in place with UV resistant tape. Duct tape, etc. is not appropriate for outdoor use. Flanged spools should be place on dunnage 4-6” from the ground. Flanges spools should be clean and have a corrosion resistant compound applied to the flange face. The flange face and opening should be covered with a “gasket type” covering such as a flangeDOT for storage. Flanges requiring impact protection should also be covered with a HDPE/Steel protector attached with at least 50% bolts/fasteners. Plywood and OSB board is not suitable for long term outdoor storage and is not acceptable when quality is paramount to the project