When one of the world’s largest producers of non-ferrous metals decided to use a revolutionary process for Copper Recovery, the operating conditions called for the use of a high performance Super Austenitic Stainless Steel.

They specified Alloy 3127 hMo for the Jacketed Autoclaves, at the core of the process.

Welders N.V. obtained the contract for the design and construction of 4 autoclaves, for an aggregate weight of 60 Tonnes. This being the first use of Alloy 3127 hMo in this application, Welders N.V. had to develop from scratch detailed fabrication procedures, particularly for welding.

Lengthy research and a continuous dialogue with the alloy producers, culminating in a programme of meticulous testing led to the definition of optimal welding parameters and to the formulation of suitable procedures.

The completed equipment was subjected to a comprehensive series of tests, including 100% radiography and passed the final inspection with flying colours.

To date, Welders’ autoclaves have given full satisfaction in service. This success was used by the alloy producer as a show-case and contributed to spreading the use of 3127 hMo in similar applications around the world.