More than 400 ton (881.000 lbs) of 22% Cr duplex stainless steel has been used to construct a number of loop reactors to operate in severe service. The reactor works at an elevated temperature and a high pressure.

Design aspects have been described. Finite element calculations have been used to optimize the geometry of complex reactor parts, in particular the inlet nozzle.

Machining of many components required the utmost accuracy in 3-dimensional measuring and milling techniques. For example, return bends of the loop reactor, made from 300–400mm (12–16") extruded pipe material, wall thickness 50mm (2") have been bent by induction heating into a precise semi-circle of approximately 1m (3') radius. Special conditions had to be applied to assure the required dimensions.

The heat exchanger is also made of duplex stainless steel pipe material, wall thickness 6mm(1/4"). A narrow tolerance on the penetration of the butt welds has been accomplished.

Welding processes include SMAW, orbital and manual GTAW and SAW. The welding procedures and the qualification testing have been reported.