Treatment system for oxide skin of main valve rod and valve disc of thermal power plant and treatment method

• Main Authors: LIU FENG, YAO YAO, ZHANG RUIXIANG, WU FANGJIE, HU YANG, HAN CHUANGAO
• Format: Patent
• Language: Chinese; English
• Published: 22.06.2021
• Subjects: BLASTING; CHEMICAL SURFACE TREATMENT; CHEMISTRY; CLEANING OR DEGREASING OF METALLIC MATERIAL BY CHEMICALMETHODS OTHER THAN ELECTROLYSIS; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATIONOR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY IONIMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; COATING MATERIAL WITH METALLIC MATERIAL; COATING METALLIC MATERIAL; DIFFUSION TREATMENT OF METALLIC MATERIAL; HEATING; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION INGENERAL; LIGHTING; MECHANICAL ENGINEERING; METALLURGY; PIPE-LINE SYSTEMS; PIPE-LINES; STORING OF DISTRIBUTING GASES OR LIQUIDS; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THESURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; WEAPONS

The invention discloses a treatment system for oxide skin of a main valve rod and a valve disc of a thermal power plant and a treatment method. After the main valve rod and the valve disc with an oxide skin jamming problem are disassembled, high-temperature-resistant and acid-resistant peelable glue is used for coating threads, bare holes and other parts on parts of the valve rod and the valve disc; then the valve rod and the valve disc are put into citric acid cleaning liquid with the concentration being 6%-8% and the pH value being 3.5-4.0, oxide skin on the surfaces of the valve rod and the valve disc is dissolved under the condition of 85-95 DEG C, and after most of the oxide skin is removed and the oxide skin remaining on the surfaces of the parts is loose and soft, dissolving of the oxide skin is completed; the residual cleaning agent on the parts is washed away with alkaline water, and the parts are blow-dried with cold air; and then the valve rod and the valve disc are polished through a mechanical me