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CN-121991571-A - PCCP pipe outer surface spray polyurea anticorrosive paint system

CN121991571ACN 121991571 ACN121991571 ACN 121991571ACN-121991571-A

Abstract

The invention provides a PCCP pipe outer surface spray polyurea anticorrosive coating system, which consists of, by mass, 60-80 parts of epoxy resin, 0.3-0.5 part of defoamer, 0.3-0.5 part of base material wetting agent and 20-40 parts of reactive diluent, wherein the epoxy primer B component is 18-30 parts of phenolic amine, by mass, the seal putty A component comprises 30-45 parts of isocyanate prepolymer A, 15-30 parts of isocyanate prepolymer B and 30-50 parts of solvent, the seal putty B component is 40-50 parts of wood powder, by mass, the spray polyurea finish A component is 100 parts of isocyanate prepolymer A, and the spray polyurea finish B component comprises 18-30 parts of amine chain extender, 70-80 parts of polyether amine and 0-3 parts of carbon black color paste.

Inventors

  • Meng Linlong
  • WANG WENJING
  • YU HAO
  • YE ZHANGJI

Assignees

  • 厦门双瑞船舶涂料有限公司

Dates

Publication Date
20260508
Application Date
20260325

Claims (9)

  1. 1. The PCCP pipe outer surface spray polyurea anticorrosive paint system is characterized by comprising an epoxy primer, a sealing putty and spray polyurea finish; The epoxy primer comprises, by mass, 60-80 parts of epoxy resin, 0.3-0.5 part of defoamer, 0.3-0.5 part of base material wetting agent and 20-40 parts of reactive diluent, wherein the component B of the epoxy primer comprises 18-30 parts of phenolic amine; The sealing putty comprises, by mass, 30-45 parts of isocyanate prepolymer A, 15-30 parts of isocyanate prepolymer B and 30-50 parts of solvent, wherein the B component of the sealing putty is 40-50 parts of wood powder; The component A of the spray polyurea finishing paint comprises 100 parts of isocyanate prepolymer A, and the component B of the spray polyurea finishing paint comprises 18-30 parts of amine chain extender, 70-80 parts of polyether amine and 0-3 parts of carbon black color paste.
  2. 2. The PCCP pipe outer surface spray polyurea anticorrosive paint system according to claim 1, wherein the anticorrosive paint system is coated with an epoxy primer, a sealing putty and a spray polyurea finish in sequence on the PCCP pipe outer surface.
  3. 3. The PCCP pipe outer surface spray polyurea anti-corrosive paint system of claim 2, wherein the epoxy primer has a film wet film thickness of 200 μm and the spray polyurea top coat has a film wet film thickness of 1500 μm.
  4. 4. The PCCP pipe outer surface spray polyurea anticorrosive coating system according to claim 1, wherein the isocyanate prepolymer A is an MDI modified isocyanate prepolymer with an NCO content of 15.5-18%, and the isocyanate prepolymer B is an MDI modified isocyanate prepolymer with an NCO content of 12-15.5%.
  5. 5. The PCCP pipe exterior surface spray polyurea anticorrosive coating system according to claim 1, wherein in the A component of the epoxy primer, the epoxy resin is E51, the solid content thereof is 100%, the defoamer is Ucat 272s, the substrate wetting agent is one of TEGO Twain 4100 or TEGO Wet 280 or a mixture thereof, and the reactive diluent is one of D131, EPG-270, GE-24 or GE-21 or a mixture thereof.
  6. 6. The PCCP pipe exterior surface spray polyurea anti-corrosive coating system of claim 1, wherein the phenolic amine is one of T-31, NX-2015, or KD-504, or a mixture thereof.
  7. 7. The PCCP pipe exterior surface spray polyurea corrosion protection coating system of claim 1, wherein the solvent in the A component of the sealer putty is a high boiling point solvent comprising one of 100# solvent oil, propylene carbonate, or 200# solvent oil, or a mixture thereof.
  8. 8. The PCCP pipe exterior surface spray polyurea corrosion protection coating system of claim 1, wherein the wood flour is one of 200 mesh wood flour or 400 mesh wood flour or a mixture thereof.
  9. 9. The PCCP pipe outer surface spray polyurea anticorrosive coating system according to claim 1, wherein in the component B of the spray polyurea top coat, the amine chain extender is one or a mixture of diethyl toluene diamine (DETDA), 3-dichloro-4, 4-diaminodiphenyl (MOCA) or dimethyl thiotoluene diamine (DMTDA), the polyetheramine is one or a mixture of D230, D400, D2000, T403 or T5000, and the carbon black color paste is solvent type carbon black color paste with a solid content of 36.8%.

Description

PCCP pipe outer surface spray polyurea anticorrosive paint system Technical Field The invention relates to the technical field of special paint, in particular to a system for spraying polyurea anticorrosive paint on the outer surface of a PCCP (prestressed concrete cylinder pipe) pipe, and especially relates to a system for spraying polyurea anticorrosive paint on the outer surface of a PCCP-C pipe. Background The Prestressed Concrete Cylinder Pipe (PCCP) has high strength, high impermeability and durability, and is widely applied to large-scale water-regulating projects such as urban water transmission main lines. However, PCCP pipes are subjected to severe conditions such as complex water environments (e.g., corrosive media including chloride ions, sulfate salts, etc.), soil stress, alternation of dry and wet conditions, etc., for a long period of time, and steel cylinders and concrete structures thereof are susceptible to chemical corrosion, electrochemical corrosion, and microbial attack, resulting in reduced strength of the pipes and increased risk of leakage. According to statistics, the PCCP pipe which does not adopt effective anti-corrosion measures can have local corrosion perforation of the steel cylinder within 5-10 years, and seriously threatens the water delivery safety and the engineering service life. Therefore, the development of high-performance corrosion-resistant coatings has become a key to ensure long-term stable operation of PCCP pipes. In recent years, due to the advantages of high construction efficiency and attractive appearance of spray polyurea, various large-scale factories gradually begin to try to spray polyurea coating on the outer surface of a PCCP pipe. The PCCP-DE pipe is coated with cement mortar on the outer surface, has fewer surface pores, is directly coated with spray polyurea finish, has a smoother appearance, has a small number of through holes, and can be repaired by adopting anti-corrosion cement at the later-stage holes; However, for PCCP-C pipes, the outer surface is a cement pouring surface, the surface is extremely smooth, a large number of air holes exist, if a spray polyurea or a 'primer plus spray polyurea' coating system is directly adopted, dense through holes appear on the surface of the coating, the appearance is extremely attractive, the through holes are repaired by using cement at a later stage, the time and the labor are wasted, the repair is difficult to complete, the coating system is in a failure state after the coating construction is finished, and the anticorrosive effect cannot be achieved. Disclosure of Invention In view of the above, the invention aims to provide a PCCP pipe outer surface spray polyurea anticorrosive paint system, which solves the problem of dense holes in the prior art caused by spraying polyurea or primer and spray polyurea on the PCCP-C pipe outer surface. In order to achieve the above purpose, the technical scheme of the invention is realized as follows: a PCCP pipe outer surface spray polyurea anticorrosive paint system consists of epoxy primer, sealing putty and spray polyurea finish; The epoxy primer comprises, by mass, 60-80 parts of epoxy resin, 0.3-0.5 part of defoamer, 0.3-0.5 part of base material wetting agent and 20-40 parts of reactive diluent, wherein the component B of the epoxy primer comprises 18-30 parts of phenolic amine; The sealing putty comprises, by mass, 30-45 parts of isocyanate prepolymer A, 15-30 parts of isocyanate prepolymer B and 30-50 parts of solvent, wherein the B component of the sealing putty is 40-50 parts of wood powder; The component A of the spray polyurea finishing paint comprises 100 parts of isocyanate prepolymer A, and the component B of the spray polyurea finishing paint comprises 18-30 parts of amine chain extender, 70-80 parts of polyether amine and 0-3 parts of carbon black color paste. Furthermore, the coating sequence of the anticorrosive coating system on the outer surface of the PCCP pipe is sequentially epoxy primer, sealing putty and spray polyurea finish. Further, the wet film thickness of the epoxy primer is 200 mu m, and the wet film thickness of the spray polyurea finish is 1500 mu m. Further, the isocyanate prepolymer A is an MDI modified isocyanate prepolymer with an NCO content of 15.5-18%, and the isocyanate prepolymer B is an MDI modified isocyanate prepolymer with an NCO content of 12-15.5%. Further, in the A component of the epoxy primer, the solid content of the epoxy resin is 100%, the defoamer is Youka 272s, the base material wetting agent is one or a mixture of TEGO Twain 4100 or TEGO Wet 280, and the reactive diluent is one or a mixture of D131, EPG-270, GE-24 or GE-21. Further, the phenolic amine is one of T-31, NX-2015 or KD-504 or a mixture thereof. Further, in the A component of the sealing putty, the solvent is a high boiling point solvent, and comprises one or a mixture of 100# solvent oil, propylene carbonate or 200# solvent oil. Further, the wood p