How we vet a heavy fabrication shop.
Published in full, because a vetting process you cannot inspect is a marketing claim. Use it on your own suppliers if it is useful, that is a better outcome for us than you taking it on trust.
Verify the equipment
Almost every heavy frame job is decided here, before anyone discusses price. These are numbers, they are checkable, and a shop that cannot produce them quickly does not know its own building.
| Crane capacity, per bay | Not the headline figure. A 50 t fabrication bay with a 15 t machining bay machines 15 t parts. |
|---|---|
| Hook height | Limits what can be turned over. Frequently the real constraint on tall weldments. |
| Stress-relief oven length | A hard number. Shorter than your piece means a subcontract move, a method substitution, or a skipped step nobody mentions. |
| Machining table size and travel | Both figures. A 6 m table with 4 m of X travel machines 4 m parts. |
| Max workpiece weight on the table | Often lower than the crane rating. |
| Distance to a deep-water port | Decides whether an oversize piece needs a road permit and escort. |
Review the documentation
A shop that welds well and documents badly will pass your first order and fail your first audit. We ask for these before a drawing is shared.
| WPS | Welding procedure specifications covering the joint types and thickness ranges we actually send. |
|---|---|
| PQR | The qualification records proving those procedures. A WPS with no PQR is a document, not a qualification. |
| Welder certificates | Dated, current, for named welders, not a folder of everything the shop has ever held. |
| Mill certificate handling | Whether EN 10204 3.1 certs are retained and traceable to heat numbers. |
| Export record | A recent shipment: destination, Incoterm, and who prepared the documentation. |
| Business licence and insurance | Basic, and occasionally revealing. |
What the documents mean in practice is set out in our guide toAWS D1.1 in plain language.
Visit the shop
A video call shows you a tidy corner. This stage is the reason we can only add shops at the rate one person can travel, and it is also the reason the shortlist means anything.
| Positioners and fixturing | Shops with proper turning gear weld in the flat position. Shops without weld overhead, slower and worse. |
|---|---|
| Consumable storage | Low-hydrogen electrodes need heated storage. Open boxes on a damp floor tell you what preheat discipline looks like here. |
| The QC office | Is there one, are there records in it, and can they find last month’s weld map in five minutes? |
| Work in progress | What is on the floor today, and does it resemble the work we would send? |
| How they answer a hard question | We ask what they think the difficult part of a sample drawing is. A shop that says "no problem" has not read it. |
Run a trial job
No shop enters the network on paperwork alone. The first order is sized so that a failure is survivable, a single piece, a fair schedule, and a scope that exercises the capability we actually care about.
What we are buying is not the part. It is the answer to three questions:
- Did the dimensional report match the drawing?
- Did the schedule hold, and was slippage flagged early?
- When something went wrong, did they tell us before or after we asked?
The third question carries the most weight. Every shop has problems. Only some of them have the habit of raising a problem while it is still cheap to fix.
Keep reviewing, and remove shops that drift
Vetting is not a certificate issued once. Ownership changes, the good foreman leaves, the shop takes on work that fills the crane you were relying on. We track on-time delivery, dimensional conformance and repair rate across jobs, and a shop that drifts comes off the list.
This is also why we will not publish a supplier count. A number like "500+ vetted factories" is easy to print and impossible to maintain at the depth described above. We would rather describe the process and let you judge it.
Take this process and apply it to your own suppliers
Everything above works whether or not you ever send us a drawing. If you are qualifying a fabricator anywhere in the world, the equipment numbers in Stage 01 and the three documents in Stage 02 will tell you more in an afternoon than a week of capability brochures.
Spotted something we have missed, or run this process differently? Genuinely interested, .
Want this run on a real drawing?
Send the frame you need built. We will tell you which shops clear Stage 01 for your specific piece, and which do not.
We reply within 24 business hours.