MANUFACTURING / JAPAN SOURCING

Drawn nonferrous tube RFQ: specify more than outside diameter and wall thickness

State the alloy, temper, delivered length and end condition, then show the fit, straightness and later processing that matter. Ask the supplier to identify the state in which the tube will be inspected and delivered.

Describe the tube you need to receive

Imagine buying aluminium tube that your workshop will cut, bend and join into an equipment assembly. An offer lists the required outside diameter and wall thickness, but omits temper, end preparation and delivered length. The price cannot yet be compared with a quote for ready-cut pieces.

Give the alloy and governing specification, temper, supplied form and intended use. Say whether you need straight lengths, coils or finished cut pieces, and which operations will happen after receipt. Yamato describes both extruded starting tubes and welded starting-tube routes in its manufacturing information.[2] If a seamless construction is required, state it explicitly and ask for evidence; “drawn” alone does not establish it.

Mark fit areas, ends and the length you can use

Identify the outside or inside surface that mates with another part. Put dimensions and tolerances on those functional areas and explain any gauge requirement. Outside diameter, inside diameter and wall thickness describe related geometry; ask the supplier to review the drawing if independent limits on all three would conflict. Keep ovality, wall variation and surface requirements separate when they affect the use.

Give cut length and tolerance, the end geometry and any burr-removal or edge requirement. If the buyer will cut away the ends, agree the usable length and any excluded end regions. Show the insert depth or joining region where it matters, and say whether a coating or later operation changes the final fit. The supplier should flag assumptions rather than silently quoting a different inspection state.

Show the tube features that the supplier must review

1Section: identify the mating diameter and wall requirements
2Length: mark usable length, end preparation and the joining region
3Straightness: agree the assessed length, support and measurement state

Schematic features only. This is not a dimensioned drawing, tolerance zone or bending/pressure design. Numbers identify enquiry topics, not measurement points or a prescribed test fixture.

Keep temper and measurement state with the dimensions

Nihon Shinkan describes straightening, cutting, cleaning and heat treatment as parts of its drawn-tube production example.[1] A drawing that only says “after drawing” can therefore leave important delivery work unresolved. Specify the required temper and ask which operations are included before inspection and packing.

For straightness, agree the length being assessed and how the tube is supported or restrained during the check. Do not treat a local check on a short piece as evidence for the full delivered length. If your workshop bends or heat-treats the tube later, distinguish requirements on the delivered stock from the final assembly requirements. Review the material condition for that later process rather than assuming the strongest temper will be the easiest to form.

What belongs in the tube enquiry?
Requirement	Show in the RFQ	Ask the supplier to confirm
Material and construction	Alloy, specification, temper and any seamless requirement	Exact supplied designation, route and evidence
Functional dimensions	Mating areas, critical diameter and wall requirements	Compatible tolerances, surface state and inspection method
Length and ends	Usable/cut length, end geometry and burr requirements	Preparation included and any excluded end region
Straightness	Assessed length and use that makes it important	Support/restraint and inspection state
Further processing	Buyer’s bending, joining, coating or heat treatment	Material-state assumptions and any trial needed
Internal condition	Use-related cleanliness and protection requirements	Cleaning scope, evidence and packing protection

Compare the offered delivery and inspection scope

Yamato describes dimensional, appearance and mechanical-property checks before packing and shipment.[2] For the offered tube, ask which checks apply, how the lot is identified, and what records accompany delivery. An available process list is not a promise that every test is included in your price.

If internal cleanliness matters, describe the actual use and the required evidence. Washing, a visual check and a quantified contamination limit are different requirements. Agree any end protection and packing with the supplier; a cap is not proof that a cleanliness limit has been met. Pressure-bearing or other regulated uses also need their own design and applicable requirements, beyond this dimensional enquiry.

Compare quotes against the same material state, lengths, end work and inspection package. Ask for deviations and proposed alternatives in writing. For a sourcing enquiry, send HAM the drawing, downstream process, quantity, destination and the decisions still open. A supplier trial can resolve a specific forming or fit question without treating an untested alternative as approved.

Questions to send your supplier

Open supplier questions

Use, mating parts and destination:
Alloy, governing specification/version and temper:
Straight lengths, coil or cut pieces; any seamless requirement:
Drawing revision, functional outside/inside diameter and wall requirements:
Surface, ovality or wall-variation requirements that matter:
Usable length, cut tolerance and excluded end regions:
End geometry, burr removal and joining or insert areas:
Straightness assessed length, support/restraint and inspection state:
Bending, joining, coating or heat treatment after delivery:
Cleaning requirement, evidence and packing/end protection:
Inspection scope, lot identity and accompanying records:
Proposed deviations, trial questions, quantity and delivery timing:

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Sources

Nihon Shinkan — How drawn tubes are made
Read drawing, straightening, cutting, cleaning and heat-treatment sections. Manufacturer process example, not a common process order or capability guarantee.
Yamato Tube Manufacturing — Manufacturing process
Read starting-tube routes, work hardening/annealing, drawing and final dimensional/appearance/mechanical checks. Drawing does not by itself prove seamless origin.