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PM HIP valve shafts

The offshore pipes for liquid natural gas (LNG) often require nickel-based so-called super compound materials (e.g. Inconel 625) for their excellent corrosion resistance.

The casting properties of nickel-based materials are not, however, sufficiently good for large and multiform pieces (e.g. valve blocks).

The casting properties of nickel-based materials are not, however, sufficiently good for large and multiform pieces (e.g. valve blocks).

Lifting pipes for the cracking process in oil refineries

Vid The catalysts used in thermophore catalytic cracking (TCC) put a heavy strain on the critical parts of the process and wear them out. The short life cycle of these parts may clearly decrease the cost-efficiency of these operations.

The lifting pipe of the cracking plant is such a component. It brings the regenerated catalyst back into the reactor. Due to high temperatures (> 600 °C) and the large flow rate of the catalyst (~ 40 m/s), there is stable local erosion in the bottom section of the pipe, in particular, where the turbulence is greatest.

The use of a metal matrix composite (MMC), Ralloy DMMC 20, as an internal coating material was selected as a solution to the erosion problem at the bottom of the lifting pipe. This material, 20% of which is CR3C2, was HIP pressed onto the internal surface of the loadbearing structure.

We have supplied several lifting pipe parts thanks to their significantly improved durability.

Slide valve sliding surfaces

Slide valves are used for controlling the flow of catalyst materials, and they are subjected to both erosion and the adhesive and abrasive wear of sliding surfaces.

We manufacture slide valve parts coated with 3 mm of PM. The coating has a tight metallurgic bond with the stainless steel base, and the coating will not crack. These coatings can be used to stretch the maintenance interval to four years.

Initially, the sliding surfaces were coated by thermally spraying a stellite coating, which was, however, poorly adhesive. In addition, the thickness of these coats was not sufficient for the desired maintenance and recoating intervals. Thicker, welded coats caused residual voltages in the components, causing deformations and cracks.