| abstract |
The invention relates to means for the chemical treatment of metal surfaces, in particular, to pastes for rust removal of metal vertical metal surfaces that work in ammonia production environments. The aim of the invention is to increase the cleaning efficiency of rust thickness up to 150 microns. A paste for cleaning metal surfaces contains, in% by mass phosphoric acid (85%) 62.1-68.1-acetic acid 2.1-2.4; liquid glass 9.0-10.0; glycerol 0.8-1.0; NP-3 sulfonal 3.53-4.25; polyvinyl alcohol 2.39-3.23; solvent 1,2-1,8; tetrafurfuryl oxysilane 0.03-0.06; water - the rest. Increasing the efficiency of cleaning from rust with a thickness of up to 150 microns is achieved by additionally adding acetic acid to the paste, as well as using sulfonol NP-3 and polyvinyl alcohol as surface-active substances, and solvent and tetrafurfuryl oxysilane as organic solvents. , and as alcohol - glycerin. 2 tab. (Ls |