We can process various pipes for water conveyance, including straight seam steel pipes, spiral steel pipes, and TPEP anti-corrosion pipes. The U.S. patent USB discloses an internal cooling method for steel pipe anti-corrosion, which involves placing a pump inside the steel pipe and spraying water onto the inner wall during the pipe's rotation. The cooling sequence is: steel pipe, FBE layer, adhesive layer, and PE layer. If the thickness at thin points is below the specified level, it is deemed不合格. If a random sample still fails to meet the standard, the entire batch is considered不合格. Given the advantages of cement mortar, such as its anti-corrosion properties and cost-effectiveness, it is increasingly recognized by engineering and technical departments at home and abroad. Major and medium-sized cities in China commonly use cement mortar as the primary anti-corrosion material for water supply metal pipelines.
The primary defect of TPEP anti-corrosion steel pipes with epoxy powder coating for water conveyance is the thin film, which is prone to external damage and shows sand holes. The manufacturing technology is demanding, the equipment is complex, and the management of field construction is difficult. Different manufacturers and batches of products may have significant performance differences, so selection should focus on mechanical properties and fit. In addition to heat resistance, it is inferior to polyethylene both as anti-corrosion material and anti-corrosion system. This leads to coatings that are too thick exceeding the standard thickness, resulting in a phenomenon; while coatings that are too thin or not applied at all will reduce the anti-corrosion capability of the steel pipes, leading to eventual rusting.
Anti-corrosion agent drips. When anti-corrosion agents condense on the surface of steel pipes like water droplets, it results in anti-corrosion agent drips. This occurrence does not directly relate to the anti-corrosive properties but it is crucial to ensure the steel pipes meet the required corrosion resistance. However, aesthetically, pipes with anti-corrosion agent drips appear dull and uneven, negatively impacting their appearance.
Corrosion-resistant TPEP steel pipes for water conveyance - Introduction to the production process of TPEP coated steel pipes.
1. Medium-frequency heating steel pipes have a higher conversion rate compared to traditional electric furnace heating methods, effectively saving electrical energy. With medium-frequency heating, the heat in the steel pipes dissipates from the inside out, resulting in a more even heating temperature and effectively ensuring the curing of the epoxy coating.
2. The technique of using internal spraying and external flooding to apply epoxy powder internally and polyethylene powder externally, which is known as curtain coating or flooding coating, employs medium-frequency heating to utilize the residual heat of the tube to cure both simultaneously, without the need for separate curing coatings.
3. The three-layer polyethylene structure is made using sintered winding technology, with the inner surface coated using thermal spray epoxy powder for corrosion resistance. The powder is melted and applied evenly on the inner surface of the pipe. The outer coating is applied using high-pressure extrusion winding, enhancing density. The coating is durable and wear-resistant, with excellent impact and bend resistance, effectively preventing mechanical damage during construction and stress damage from plant roots and soil environment during use.
4. Both internal and external corrosion protection achieved through simultaneous coating of internal epoxy and external 3PE, a core technology that forms a film in one go upon simultaneous curing. Coating both surfaces simultaneously not only significantly reduces coating time and boosts efficiency but also, during the process, minimizes heat loss with the钢管 wrapped by both internal and external coatings, fully utilizing the latent heat within the钢管, thereby enhancing thermal efficiency. In recent years, in response to new issues and requirements encountered during the use of pipeline coatings, coating manufacturers in various countries have either improved materials on the basis of traditional FBE and 3LPE or developed new coatings. Some practical application achievements have been made, and these are gradually being applied in production.
