Alternative Materials for Floor and Lower Waterwall Tubes in Black Liquor Recovery Boilers, 2000 Engineering Conference Proceedings
Angela Wensley, Ph.D.--Cracking or corrosion thinning has necessitated the replacement of type 304L-clad composite tubes in floors and lower waterwalls in many cases. Although replacement is often done in kind, there are a number of alternative materials that may have improved resistance to cracking and thinning. This paper discusses several of these alternatives that range from carbon steel to composite tubes clad with alternative alloys, or to tubes with weld overlaid, thermal sprayed, or diffusion coatings. Also discussed is the damage that can be done to the tubes before they ever enter service.