Clareok,
Agree 100% with David and LI's comments.
Just like to add a bit from personal experience.
Codes / Standards do not give a lot of guidance so it basically comes down to your companies Quality Plan / Quality System requirements for traceability.
As a Clients Representative I do many Quality Audits prior to a contract being awarded and traceability is always on the list.
If I see a company performs transfer of heat numbers professionally then I have confidence that what the client is buying actually matches up with the Quality records supplied.
I performed a pre-award audit on a company in Thailand that was hoping to win a huge contract for supply of fabricated steel to a mine in Australia (hoppers, tanks, gantries, overland conveyor systems etc).
Structural is much harder than piping for traceability as there are so many individual pieces but they had come up with an innovative way to resolve this.
Every single part (even tiny gussets) had the heat number/ plate number stencilled on with a hard stamping machine.
Initially I was sceptical but took about 30 mins to show me how the hard stamping number linked back to the Cutting Plan.
So, a future failed part could be easily traced back to the actual plate it was cut from and all other items from that same plate could be investigated.(previously it would be only the heat number and that may have involved 20 x similar plates)
Sorry if I have rambled on a bit but just trying to show that the more emphasis you place on traceability the more happy clients you will have,
Cheers,
Shane