Mechanical engineering

Specialised technical expertise

Specialised technical expertise

We have been in business since 1912. Over the years, we have acquired both expertise and hands-on experience. As a result, we know how to comply with international regulations and offer advice on the optimal design code or material type for your process.

All process equipment is tailored to meet your specs.

Numerous design codes

In addition to your specs, we mechanically engineer in accordance with many design codes. These include:

  • ASME VIII Division 1
  • EN 13445
  • AD Merkblatter
  • Dutch Stoomwezen rules (RtoD)
  • PED
  • API 661
  • TEMA
  • British Standard

Thermal design complies with HRTI regulations; we re-mark materials per LRQA’s G0304 certificate.

Furthermore, we ensure optimal quality by extensively testing our products. For instance, we x-ray the weld seams of our products and perform hydrostatic tests up to pressures of 600 barg.

Quality System

We also hold several international certifications, including:

  • ISO 9001
  • PED module H/H1
  • ASME-U
  • ISO 3834

Inspections are performed by LRQA, TUV, ABS and Bureau Veritas, among others.

Please note that this list of design codes and certifications is not complete. For more information, read about our Quality System.

Many material types

Testimony to our customised products is the range of materials we work with. Among these are:

  • Carbon steel
  • Stainless steel
  • Duplex and Super Duplex steel
  • Heat-resisting steel
  • Low-alloy steel
  • High-nickel and cupro-nickel alloys such as Inconel, Hastelloy, Incoloy, Monel, CuNi 90-10, CuNi 70-30
  • Alu-Bronze
  • Titanium
  • 254 SMO

For optimal quality, we separated the work with stainless steel and non-ferrous materials on the one hand and carbon steel on the other. These are carried out in 2 separate hangars.

Specialised welding

All materials are processed using multiple specialised welding techniques, including: 

  • Weld overlay by wire and strip
  • Orbital tube-tubesheet welding (with and without filler metal)
  • Submerged arc welding

The wall thickness of our materials is more varied than that of others, including other Rootselaar Group companies. Combined with our specialised welding techniques, we offer such technical expertise that we are regularly called upon by other Rootselaar Group companies.

More information

Would you like to learn more about our mechanical engineering expertise? Or do you have a question about a specific design code or material type?

Feel free to contact us at any time.

Contact us

More information?

Do you have a question about our products or services? Feel free to contact us at any time. We would love to hear from you!

Contact us

Our story


We work with complex materials and apply specialised (welding) techniques to meet our customers’ demands. Read how we face the challenges of constantly changing industry needs.

About Kooiman