This large fabrication of HASTELLOY^® C-22^® alloy is shown here being readied for shipment to a papermill in the southeast. C-22 alloy was selected for this application after extensive testing in the actual bleach washer environment. It has already given over 10 years of service with no corrosive attack.

Twenty different materials were tested for this hydrofluoric acid prescrubber after the original material failed. C-22 alloy had four times better corrosion resistance than the original material and 20 percent better than the next candidate. The process involves 20 percent HF, 64 percent H2SO4 and 16 percent water at 150 to 200°F.

Sleeved electrogalvanizing finishing rolls made of HASTELLOY C-22 alloy are ready for placement in a steel finishing manufacturing line. C-22 alloy helps reduce defects on the rolls which is necessary to produce defect free galvanized steel for the automotive industry.

Solid rocket propellant effluents and salt air caused pitting and crevice corrosion attack of stainless steel. C-22 alloy was selected over 19 different alloys for the clamshell bellows after extensive testing. The bellows have been in service for more than 12 years.

Acid pump, fortified with a C-22 alloy sleeve, is still providing excellent service after 9 years in a continuous stainless steel pickling operation. The acid consists of 2 percent hydrofluoric acid, 20 percent hydrochloric acid, and as much as 40 gm/liter of iron, at 170°F.

The largest fabrication of HASTELLOY^® C-22^® alloy known to-date is shown here being thinsheet lined for exposure in a utility flue-gas desulfurization plant. C-22 sheet is still providing excellent service after 10 years.

Conditions were so severe in C-stage bleaching operations at one mill that even C-276 alloy welds were suspect. As a preventive maintenance measure, 3 mm was ground off each weld and replaced with a weld deposit of C-22 alloy. This photo, taken 18 months later, shows the welds virtually unaffected. At this printing, it is still in service after 7 years.

C-22 alloy was selected to replace a FRP fan because of its durability and corrosion resistance. This fan will handle the incineration of radioactive and hazardous wastes.

Haynes International, Inc. 800-354-0806 765-456-6012

HASTELLOY® C-22® alloy Information*

HASTELLOY^® C-22^® alloy Information*