Welded Stainless Steel tubes and pipes

Welded Stainless Steel tubes and pipes

Gestión de Compras have the means to produce and supply welded stainless-steel tubes in a wide range of lengths, diameters and thicknesses, supplying in all the alloys to different sectors.

Gestion de Compras is able to supply manufactured products under integrated quality control from raw material through to the final product. We can produce among different welding methods:

  • ERW – High frequency electric resistance welding
  • TIG – Insert gas arc welding
  • Laser welding.
  • SAW – submerged arc welding

Our tubes are mainly used in construction or in the food, pharmaceutical and automotive industries, as well as for domestic installations or decorative purposes, marine industry.


Our welded stainless-steel pipe is made through tube-shape stainless steel sheets and subsequently the seam is welded longitudinally. After welding a grinding is applied on the seam. Final processes are the annealing and the quenching according to the applicable standard or specifications received by our customer.

Depending on the outer dimension, wall thickness and the final application, we are able to produce our stainless-steel tubes and pipes by different ways:

Strip welded stainless tubes

The tube get by this process is mainly produced from hot-rolled slit pre-material or cold-rolled (which have smooth finish, closer tolerances and strong mechanical traits).

These tubes are made from a coil of strip; this strip is unwind into a strip accumulator which enables continuous tube production. The second step is the forming of the tube, the welding and the initial testing which comes before the ground and the calibration. The next steps are the annealing, cooling, straightening and recalibration, pickling and testing.

Finally, we apply the marking, we cut in the specific length and we make the deburring and final inspection according to the requirements of the project in order to pack and deliver the tubes.

Tick wall stainless steel pipe

This manufacturing process uses plates or sheets to produce mainly tubes diameters higher than 500mm and/or tubes with thick wall thickness (>6mm).

These tubes are made rolling a plate using a bending machine or even a hydraulic press, after that, the welding is made. The next step is applying the grinding into the seam, the annealing and the cooling processes. The surface finish is improved applying a sand blasting, a pickling process and the straightening, getting the final tube which is cut, tested and packing according to the requirements of our customers.


  • Lower costs than seamless process
  • More consistent concentricity compared seamless.
  • Good tolerances.
  • Thinner wall, large diameter applications


  • Welded points are vulnerable to cracking up under high pressure
  • Less resistant to corrosion than seamless.
  • Stress concentration
  • Slight impurities

Materials and products

Our range of materials includes the most commercial austenitic grades 304 (1.4301, X5CrNi18-10) , 304L (1.4306, X2CrNi18-10), 316 (1.4401, X5CrNiMo17-12-2),  and 316L (1.4404, X2CrNiMo17-13-2) stainless steel tubes; but also the grades 317, 317L, 321, 310S, 310, 630, 201, 303 (1.4305, X10CrNiS18-9).

304 in seamless pipes is the most used standard commercial grade as it has good corrosion resistance and good machinability

316 seamless pipes have much better corrosion resistance and this grade recommended for marine environments or coastal applications.


Standard and certificates


  • Mill test certificates (MTC) according to EN 10204: 2.1, 3.1, 3.2.
  • PED Pressure equipment directive.
  • Our factories comply with quality management systems as ISO 9001, ISO 14001 and OHSAS 18001.
  • Size reports are issued by our laboratory or by a third party (SGS, TUV, other)
  • Our products comply the general regulation and the specific certificated regulations in manufacturing products that requires them:
    • UNE-EN 10217-7: 2015
    • ASTM A249
    • ASTM A269
    • ASTM A312
    • ASTM A358
    • JIS 3463
    • DIN17440
    • ISO 1127: 1992
    • NFA35-572 / NFA35-576-582 / NFA35-584
    • Etc.