Pipeline waterproofing and anti-corrosion construction plan

Depending on the different leakage and wear conditions of the pipeline, there are also different material choices for the inner lining of the pipeline. There are lined wear-resistant ceramic pipes (lined with aluminum oxide, silicon carbide, zirconia, silicon nitride, celon, aluminum nitride, boron nitride, etc.); Wear-resistant alloy pipe Turtle shell mesh wear-resistant pipe fittings Steel-rubber wear-resistant pipe Steel-plastic wear-resistant pipe Wear-resistant cast stone pipe Wear-resistant self-spreading composite pipe Rare earth alloy wear-resistant pipes, etc.

Main function

Wear-resistant pipes are not only applied in ash removal, slag discharge pipes, powder feeding and powder return pipes, and desulfurization pipes in coal-fired power plants, but also widely used in the following industries:

Mine: water-coal slurry, coal washing slime, mine filling material, and mine coal powder in the coal industry;

Metal mines: Wear-resistant elbows for the transportation of concentrates and tailings;

Metallurgy: Pipelines for coal injection and slag transportation in blast furnaces for iron smelting in steel plants; CAO and zinc sand conveying pipes, preferred wear-resistant elbows for conveying ferroalloys in steelmaking and ladle refining, etc.

Cement plant: raw slurry conveying, coal powder conveying, discharging of elevators, pneumatic conveying and loading/unloading of finished cement, and wear-resistant elbows for concrete conveying in the rotary kiln wet process production line.

Chemical plant: Coal powder conveying pipelines, wear-resistant elbows for conveying raw materials such as silicon powder.

Restoration process:

(1) Construction Conditions:

During construction, the surface temperature of the base material must be 3℃ higher than the dew point temperature, and the relative humidity must be less than 60%.

2. It is recommended that the construction be carried out in an ambient temperature range of 15℃ to 32℃.

3. The construction area must be isolated from water sources and dust pollution sources.

(II) Formulate the construction plan:

Based on the new equipment or drawings, determine the dimensions of the exterior corridor that the repaired equipment should reach.

2. Make molds of the corresponding size.

(III) Surface Treatment:

For the eroded and damaged parts of the pipeline, repair welding should be carried out, and steel plates/reinforcing bars of the same material or similar to the base material of the equipment should be selected for the frame welding.

2. Degreasing and dehumidification treatment: Remove the grease from the surface of the pipeline and wipe the surface of the workpiece with new cotton yarn. Adjust the flame to 10CM in length with oxygen acetylene and bake the surface of the workpiece repeatedly and evenly at a speed of 5cm/min to remove the grease and moisture on the surface of the workpiece.

3. Sandblasting rust removal: Remove the oxide layer on the surface of the pipe. Visual inspection shows a uniform metallic color on the sandblasted surface. After sandblasting treatment, workpieces are not allowed to be directly touched by oily gloves on the sandblasted surface. Dust and dirt are not allowed to fall. The inner walls and surfaces of the pipes after sandblasting treatment should be protected from moisture. For the parts that do not need to be treated, proper covering and protection should be done.

(4) Selection of wear-resistant and anti-corrosion materials:

1.RJ-C-16 wear-resistant material. This material is a two-component one, water-resistant, wear-resistant and anti-corrosive. Its relative wear resistance is 1 to 3 times that of medium carbon steel.

2.RJ-YHL-C-1.0-2.0 composite ceramic wear-resistant material. This material is a two-component one, water-resistant, wear-resistant and anti-corrosive. Its relative wear resistance is 1 to 4 times that of medium carbon steel.

3.. RJ-YHG-C-1.0-1.4 special wear-resistant material. This material is a two-component one, water-resistant, wear-resistant and anti-corrosive. Its relative wear resistance is 1 to 7 times that of medium carbon steel.

According to the actual working conditions, any one of the above three recommended materials can be selected. The RJ-C series wear-resistant materials are all two-component. A layer of 3mm-8mm thick of this material is applied to the parts of the pipeline that need protection. After the material is applied, during the curing period, it can penetrate to a depth of 3-5mm on the surface of the pipeline and closely combine with the base surface of the pipeline, playing a sealing and blocking role. It effectively prevents water seepage and leakage. The main aggregate in the material is super-hard particulate matter. The above three materials have different materials, and their wear resistance is 1 to 7 times that of medium carbon steel, which can resist the impact of solids (such as sand and gravel) carried in the fluid for a long time. The anti-corrosion polymer materials added to the material, after curing, can play the role of anti-corrosion, anti-oil and anti-acid (alkali) (add corresponding anti-acid (alkali) media according to the working conditions), and are suitable for equipment overcurrent erosion (-20℃ to 80℃), large-scale pipeline repair, and pre-coating of wear-resistant layers on pipelines, which can extend the service life of pipelines and reduce the frequency of equipment maintenance.

(V) Construction of Wear-resistant materials

Precautions for the use of RJ series wear-resistant materials:

①. Mix strictly in accordance with the proportion of the RJ series wear-resistant materials and stir evenly. Uneven stirring may result in local wear resistance. The specific blending ratio and curing time should be referred to the product data sheet.

② After thoroughly mixing the materials, they should be used up within 3 minutes; otherwise, the materials will solidify and harden. The solidified materials cannot be used. If the solidified materials are used, local delamination may occur.

2. The sequence of using repair materials for RJ equipment:

①. First, preheat the sandblasted pipeline. Then, mix and stir the RJ-C-16 wear-resistant material in proportion evenly. Use a trowel or plastic scraper to apply the mixed repair material to the treated part of the pipeline, in one direction, and press it down while applying.

②. Before the material initially sets, use a scraper to smooth out the surface of the coated material.

③. During the period of waiting for curing after large-scale coating of the pipeline, repair the leaking parts of the pipeline. Use heating tools to heat the leaking parts. It is necessary to ensure that there is no water, no oil and no pollution. First, apply two coats of RJ wear-resistant material primer for sealing and penetration treatment. After the surface is cured (not sticky to the touch), apply one layer of RJ-C series wear-resistant material. Then, use reinforcing tape for the first layer of reinforcing treatment. According to the actual situation, apply two or more layers of wear-resistant material coating and reinforcing tape treatment. Both sides of the reinforcing tape need to be extended as needed.

③. After the initial setting, thoroughly mix and stir the RJ-C-100 wear-resistant material in proportion. Use a plastic scraper to evenly apply the stirred material to the surface that has been coated with the wear-resistant material for sealing treatment. Before the initial setting, repair and smooth the surface.

④. When the temperature is relatively low, the RJ-A component wear-resistant material can be heated to 30-40℃ to make the material easy to stir.

⑤. Heating and curing: After the construction is completed, the workpiece should be left to stand for 30 minutes for heating and curing, and the heating should be carried out according to the curing temperature table.

(VI) Grinding Acceptance:

1. Grinding: After the pipe is heated and solidified, it is ground strictly in accordance with the size of the workpiece until it reaches the standard size.

2. Acceptance: Assemble the supporting equipment to ensure normal operation. The sealing mating surfaces should be tested and matched as qualified.

3. Painting: After passing the inspection, the workpiece is painted. The painted surface should be uniform and no sagging is allowed.

The above construction plan is applicable to the repair plans for most pipelines that have leakage, abrasion and cavitation. The specific construction shall be subject to the construction plan formulated by the company's technical department after on-site survey results.