Bonding makes it possible: simple, good and efficient production of composite steel tubes
By using special adhesives from our partner Huntsman Advanced Materials it has been possible for Bodo Möller Chemie and the Erndtebrücker ironworks (EEW) to produce so-called compound-liner clad tubes (CLC-tubes) inexpensively. These are used where the quality of metallurgically bonded clad pipes is not required and the quality of simply mechanically bonded liner tubes is not sufficient.
The Erndtebrücker ironworks in North Rhine-Westphalia produce steel tubes (tubes for processing, pipelines and construction) for use in offshore facilities, power plants, chemical and petrochemical industries and is well known for building large steel constructions.
Together with the research and development team of the EEW Bodo Möller Chemie has developed a method for economically producing a clad pipe that offers a quality standard between metallurgically bonded clad pipes and mechanically bonded liner tubes and at the same time is inexpensively and easy to produce.
To perform the required tasks composite plates made of CMn-steel and corrosion resistant alloys (CRA) were prepared. The challenge was to find a suitable high-performance epoxy resin adhesive that allows the plating of C-steel heavy plates with Cr-Ni-stainless steel sheets, which then can then be formed and welded to heavy composite tubes.
All competing adhesives were tested: they were cured after production in a press at 180 °C to determine differences in fracture behaviour and elasticity. The adhesive Araldite AV 4600 from Huntsman Advanced Materials provided a strong and lasting glue line with no evidence of separations and showed the highest shear strength of all the products tested.
Araldite AV 4600 is a one-component thixotropic adhesive curing at high temperature, which shows also at low temperatures by up to -40 °C an exceptionally high impact resistance and tenacity. Since this adhesive has also a temperature resistance up to 120 °C, the CLC-tubes produced in this manner can also be used for applications in the offshore or marine industry.
For the manufacture of composite sheets which are required for the production of CLC-tubes, the EEW combined bonding with resistance spot welding. This bond was strong enough to produce tubes even with relatively small diameters up to 180 mm. Thanks to this combination the curing process was possible in a standard bogie hearth furnace, impacting positively on economic production.
The successful introduction of this new production method provides EEW its goals for efficient utilization of existing facilities to achieve cost-effective production of new pipes.
We wish furthermore great success!