Precision tubing for the industrial sector
The technical challenge of the industrial environment
Continuous rotation is unforgiving
A conveyor belt roller turns for the whole shift, every day. If the tubing acting as the shaft retains a pronounced internal weld bead, the bearing is forced: friction, heat, vibration and noise appear, and the service life of the assembly is shortened. What begins as a badly resolved hundredth of a millimetre ends as unplanned maintenance downtime.
Long production runs demand repeatabilit
Long production runs demand repeatability, not just precision. Making one perfect part is easy. Making a hundred thousand identical ones is the job. In conveyors and storage systems the customer assembles on an automated line: if the tolerance drifts between batches, the line stops.
The environment punishes the material
Cold stores, humid environments, constant handling, continuous rubbing. The component needs a finish that lasts and, when it is on show, one that also looks right.
Applications where you will find us
Conveyor belt rollers
- Roller shaft The tubing acts as the shaft the roller turns on. With the OPTIM range we control outer diameter, bore and wall thickness simultaneously, with an internal weld bead ≤ 0.15 mm: the shaft enters the bearing with exactly the clearance specified in the drawing, with no play and no parasitic friction.
- Small-diameter roller bodies In light-duty and gravity conveyors and dynamic picking racks, the roller itself is made from small-diameter tubing. The PRECISE range goes up to ⌀ 25 mm with a mirror bore and controlled concentricity.
Storage and materials handling systems
- Industrial wheels and castor axles The same principle as the roller: if the axle is not calibrated, the trolley squeaks, pulls to one side or seizes under load.
- Guides, rails and structures Thin walls with the formability for tight bends without cracking or ovalisation, when the design aims to save weight without losing rigidity.
- Non-circular profiles Square, oval or flat oval section to EN 10305-5, when the structure calls for it.
Components with a finish
- Direct chrome, zinc and brass plating The PREMIUM range leaves the factory with a bright, non-porous outer surface: the processor saves the polishing stage before the plating bath and prevents the imperfections in the steel from surfacing after treatment.
- Screen printing and marking When the component needs graduations, identification or visible differentiation.
The right range for industria
OPTIMRoller shafts and industrial wheel axles. Simultaneous control of bore and outer diameter, weld bead ≤ 0.15 mm
PREMIUMComponents with a finish: direct chrome, zinc or brass plating, with no prior polishing
PRECISERoller bodies, cylinders and mechanisms with internal sliding. Mirror bore. An alternative to seamless tubing at 40% to 80% lower cost
Not just the tubing: the finished part
- Coil format or cut-to-lengthCoil supply eliminates end-of-bar scrap on automated lines and reduces stoppages for bar changes. Cut-to-length delivers the tubing at exactly the length specified in the drawing, ready to load into the machine.
- Tubing transformed into a component ready to assembleWhen the customer needs it, we do not deliver tubing: we deliver the finished part. Cutting, bending, punching, end forming, threading, machining and surface finishing —to drawing— so that it reaches the assembly line ready to fit. Fewer suppliers to manage, less intermediate handling, fewer errors.
- Documentary certification with every deliveryWe issue certification to EN 10204-2.2 (declaration of conformity with non-specific inspection results) or EN 10204-3.1 (inspection certificate with specific results for the batch supplied), depending on what the customer's quality system requires. In-house laboratory at the plant.
Why industrial manufacturers trust Delmàs
A family-owned business in La Roca del Vallès, specialising exclusively in small-diameter welded and calibrated steel tubing (⌀ 3–25 mm).
Below 8 mm, the supply of precision calibrated tubing all but disappears. That is where we have been working for decades.
Against seamless tubing, with uncertain and unpredictable lead times, the PRECISE range offers equivalent performance with reliable planning. For a plant that cannot stop, predictability is worth as much as price.
Manufacturing powered 100% by renewable energy since 2006, with two photovoltaic self-consumption installations. More and more industrial customers need this for their own carbon footprint reporting.
Questions we hear every week
What tubing is used for the shaft of a conveyor belt roller?
Calibrated tubing with a controlled bore and a minimal internal weld bead. In the OPTIM range (⌀ 3–10 mm) we keep the bead at ≤ 0.15 mm, so the inner shaft turns without unwanted friction and the bearing is not forced.
Do you manufacture the tubing or distribute it?
We manufacture it. Delmàs has been a manufacturer of welded and calibrated tubing since 1956, at its plant in La Roca del Vallès (Barcelona). We work from the customer's drawing, not from a standard catalogue.
Can you manufacture non-standard sizes?
Yes. We do not standardise: if your application needs 6.2 mm or 8.25 mm, that is the size we manufacture, controlled to a hundredth of a millimetre.
Can you replace seamless tubing in cylinders and mechanisms?
Yes. The PRECISE range offers a mirror-finish bore to EN 10305-2 and replaces seamless tubing at 40% to 80% lower cost and with predictable lead times.
Do you deliver the finished component or just the tubing?
Both. As well as tubing in coil or cut to length, we transform the tubing into a finished component ready to assemble: bent, punched, end formed, machined and with whatever surface finish the drawing requires.
Is your roller noisy, or does your shaft not fit as it should?
Send us the drawing. Our technical team assesses the application and prepares a physical sample so you can check the internal weld bead and the tolerance on your own line, before committing to a production run.