Pipes

Aluminium round tubes are the most ordered profile in our catalogue and the most frequently mis-specified. Not because the product is complicated. Because two words, tube and pipe, get used as if they were interchangeable, and they are not. One is measured from the outside, the other from the inside, and ordering by the wrong number is the single most common reason a delivered length does not fit the fittings waiting for it. We extrude round tubes and pipes at our facility in Indonesia, so this page starts where every quotation should: with the distinction.

Tube or Pipe? Get This Right First

A tube is specified by its outside diameter and wall thickness. A 25 × 2 mm tube has a 25 mm OD, full stop. Tubes are structural and general-purpose products: the outside dimension is what mates with clamps, bearings, brackets, and human hands.

A pipe is specified by its bore, the inside diameter, because a pipe exists to move fluid and the bore is what sets the flow. The outside dimension is a consequence, not the spec.

The practical rule we give every new customer: read your drawing. If it states an OD, order a tube. If it states a bore or a nominal pipe size, order a pipe. Send us the drawing and we will translate either way, but the distinction is worth thirty seconds of checking before any order, ours or anyone else's.

What Buyers Call This Profile Across Markets

In the UK, Australia, Canada, and Europe, the general product family is simply tubes, with structural drawings often specifying a CHS (circular hollow section). In the United States, the search term is round tubes, and fluid applications use round pipe. The metal's spelling splits along the usual line: aluminium in British English markets, aluminum in the US.

Same extrusion, several names. We quote against all of them, and against drawings in either convention.

Seamless vs Semi-Seamless: What the Words Actually Mean

This is where we will save some buyers money. Aluminium tube is produced two ways. Seamless tube is extruded so that no longitudinal joint exists anywhere in the wall. Semi-seamless tube comes from a porthole die: the billet splits around the die's bridge and rejoins under extreme pressure inside the die, producing a solid-state weld line running the tube's length.

That porthole seam is metallurgically bonded, not a crack waiting to happen, and for handrails, furniture, rollers, frames, and architectural work it performs identically to seamless at a lower cost. Our position: most buyers paying a seamless premium do not need it. Reserve seamless for pressure-bearing duty, hydraulic and pneumatic lines, and applications where a regulation or customer specification explicitly demands it. For everything else, semi-seamless is the rational specification, and we will tell you which one your application calls for.

Where Round Tubes and Pipes Get Used

• Architecture and handrails, where the circular section looks the same from every angle and has no edge to catch on.
• Heat exchangers and cooling, because 6063 conducts heat at roughly 200 W/m·K, several times the rate of steel.
• Fluid transport, from compressed-air lines to drainage, in pipe-specified bores.
• Structural and transport frames, since a circular hollow section carries identical bending stiffness in every direction and is the most torsion-efficient shape there is.
• Rollers, sleeves, and machine components, where concentric walls and a clean OD matter.

Specifications

Diameters and walls outside this table can be quoted from our die library or tooled as a custom die.

Choosing the Alloy

6063-T5 is the default for handrails, furniture, heat-transfer work, and anything anodised: it extrudes into thin, concentric walls and finishes evenly. 6061-T6, with a yield strength near 240 MPa against 6063's 145 MPa, belongs in load-bearing frames, machine parts, and any tube that doubles as a structural member. If the tube carries people, as a handrail or a guard does, say so in the enquiry. That detail changes our recommendation on both alloy and wall.

Custom Tubes from Our Factory in Indonesia

The usual three service levels apply:

1. Cut-to-size from standard dies, delivered as finished lengths with square, deburred ends.
2. Non-standard diameters or walls from the existing die library.
3. Custom dies, including internal ribs, screw bosses, or stepped walls for proprietary components.

Material test documentation can accompany the delivery on request. Send your drawing, your fitting schedule, or just the OD and duty, and our team will reply with the tube-or-pipe call, an alloy recommendation, price, and lead time from our factory and warehouse in Indonesia. For tubes chosen on looks rather than load, the patterned profiles on our Decorative Tubing page are the other half of this catalogue.