Fundamentals of Bristle Blasting Process for Removing Corrosive Layer

This paper describes a recently developed mechanical method for corrosion removal termed the “bristle blasting” process.  The process involves the use of a specially designed rotary bristle tool, which is dynamically tuned to a power tool spindle that operates at approximately 2,500 rpm.  Key issues that are discussed in this paper include:
▪  kinetic energy equivalence between rotary bristles and grit blast media,
▪ unique dynamic response of specially designed bristles which, upon striking the corroded surface, immediately retract (i.e., rebound) from the impact site,
▪ the nature of the post-collision indentation that arises at the interface of hardened bristle tip and steel surfaces, and
▪ corrosion removal capability of the bristle blasting process, including the cleanliness and texture/anchor profile of treated surfaces.
    Surfaces generated by the bristle blast process are shown to be similar to both the visual cleanliness and texture that is characteristic of grit blasting processes.  Finally, a case study is reported that demonstrates the cleaning performance and life expectancy of the tool when used for de-corrosion of API 5L piping, which is commonly used in petroleum industries.