Anti-corrosion steel boiler frame

1.2.5 The chemical rust removal level shall be Pi level: there shall be no visible grease or dirt on the surface of the steel, and there shall be no trace of unfinished oxide scale, rust and paint. coating on the steel surface. Residual spots are allowed by hand. It must be removed manually or mechanically and eventually the surface must return to its original rust-free appearance.

1.2.6 The surface of the steel structure qwhich has been treated must not be polluted again. When polluted twice, the surface must be treated again. 1.2.7 For heavily polluted steel structures and severe corrosion. In reconstruction and expansion projects, steel structures must be surface pretreated, and the treatment methods must comply with the following regulations:

1 The surface of steel structures contaminated with grease may be removed by organic solvents, hot alkaline solutions or emulsifiers and cooking grease.

2 The surface of the steel structure which is contaminated with oxides or has old layers of paint attached to it can be cleaned by methods such as shoveling and baking.

1.2.8 The base coat of the treated steel structure should be painted with primer in time and the interval should not exceed 5 hours.

How to choose coatingsRobust anticorrosion for thermal power plants

Steel structures exposed in corrosive atmospheric environments mainly include steam turbine islands, boiler islands, wastewater treatment plants and desulfurization systems. steel structure accessories, coal unloaders and its coal transportation system, etc. The corrosion environment of these steel structures exposed to the atmospheric environment is quite harsh. Many power plants are built on the coast and are affected by corrosion caused by the ocean atmosphere. The CO2, SO2 and coal ash particles produced by the plant itself are very corrosive to the steel structure. According to the ISO12944-2 standard, most steel structures of thermal power plants are at corrosion level -2. If they are stand-alone power plants such as oil refineries andsteelworks, they are at the C5-1 anti-corrosion level.

These steel structure coating systems should have an anti-corrosion lifespan of more than 15 years, and the total dry film thickness of the coating system should be more than 240 um if it is It’s a C5; -1 corrosive environment, the total dry film thickness is required to reach 280UM-320UM.

The primer can use a zinc-rich epoxy primer or an inorganic zinc-rich primer. According to the requirements of ISO12944-5:2007, the dry film thickness is 60um (can also be adjusted between 40um and 80um). When using an inorganic zinc-rich primer, mist spraying is required:

Full spray process to avoid pinholes and blisters if a non-rich primer system zinc is used, such as zinc epoxy; Phosphate primer, aluminum epoxy powder primer, etc. The dry film thickness of the primer shouldt be at least 80 um. Under C5-1 corrosion conditions, although non-zinc-rich primer systems can also be used, zinc-rich primers are preferred to ensure better anti-corrosion performance.

The intermediate paint can be epoxy intermediate paint (mircopyrite), which must have good shielding performance, good compatibility with the base paint and a thickness of 50 to 200 um.

The top coat can be an economical acrylic polyurethane top coat, or a cross-linked fluorocarbon top coat or polysiloxane coating with improved gloss and color retention and resistance to fading. corrosion. The dry film thickness is 50 um to 80 um.

Chuangjiang anti-corrosion paint is a high-performance anti-corrosion system consisting of a zinc-rich epoxy primer and an acrylic topcoat. The paint has excellentAnti-rust performance, strong adhesion and dries quickly. room temperature. The paint film contains zinc powder.High, with cathodic protection, this system has excellent chemical resistance and excellent weather resistance, providing high protection to the substrate.

Product Classification

Products are divided into two types: primer and topcoat based on their uses.

Scope of application

Mainly used for steel structure roofs (inside, walls), steel pipes, storage tanks, containers, ships, offshore platforms, port facilities and harsh corrosive environments.

Construction technology

Metal structure roof (wall, interior) anti-rust and anti-corrosion construction technology: rust removal → cleaning → anti-corrosion primer painting (sprayedsation) → inspection and re-coating → Application of an anti-corrosion top coat (spray) → Application of an anti-corrosion top coat (spray)

1. Rust removal process requirements: The base coat is thoroughly cleaned and special equipment is used for grinding and rust removal. removal or sandblasting and rust removal. There should be no rust stains on the base coat and oil, grease, sand, iron sand and metal oxides should be cleaned off. After rust removal, the primer should be sprayed within six hours for anti-corrosion treatment. Before the spraying process, if it rains or causes moisture on the base steel surface, wait until the environment reaches construction conditions and then blow with it. dry compressed air. Remove rust after drying surface moisture; the surface of rusted steele reaches Sa2.5 rust removal level. The surface should be cleaned with brushes and other tools before moving on to the next process. steel after passing rust removal will show a metallic shine. Rust stains and paint on the metal surface should not exceed 5%. If rust returned before priming, re-grind or sand to remove rust. avoid reducing roughness.

2. Cleaning process requirements: Use high-pressure cleaning equipment, the surface of the base should be clean, and the gaps, uneven parts and hidden corners of the base should be thoroughly cleaned. The base surface should be firm and flat, and uneven or cracked parts should be reinforced before construction; the base surface should be thoroughly cleaned and there should be no impurities such as dirt, floating dust, debris, free water, de oil or debris. objects, etc., and keep the base surface clean and hygienic at all times.

3. Anti-Corrosion Primer Process Requirements: Before construction, the base surface should be free from floating rust, wet marks, water accumulation and clean construction should not be carried out in rainy weather. Special equipment for high pressure spraying is used for construction. Building materials must be free of sediment and subject to strict inspection. Once the packaging barrel is opened, it should be used as much as possible on the same day. The materials should be evenly agitated using a special grinder to ensure high-pressure pulverization during the construction process. Special equipment must be free from clogging, and the spraying process must be uniform, without accumulation or omission.

4. Check and repaint: favor the corners,side seams, horizontal overlaps, vertical overlaps, fan openings, protruding roof ducts, air conditioning ducts, junctions between metal plates and parapets and screw fixings (weak corrosion-resistant bonds of other roofs (walls, interiors) such as wall corners, C-shaped steel, H-shaped steel, trunking, ceiling supports, pipes) should be carefully inspected to ensure that all edges and corners are sprayed in place. .

5. Anti-corrosion topcoat process requirements: Topcoat construction can only be done after the primer surface is dry. Special equipment for high-pressure spraying is used for construction.The anti-corrosion coating after construction must have uniform thickness and meet the design requirements; no defects such as falling, accumulatedcracks, edge distortion, bubbling, delamination and loose ends are not permitted. The construction ensures seamless and complete coverage of the base layer. Once the project is completed, it will enter the maintenance period and no one will be allowed to enter the construction site.