Abstract: This paper investigates the selection, application, and durability of corrosion-resistant water supply pipe materials. It analyzes the characteristics of the water supply environment in high-rise residential buildings and their impact on pipeline corrosion, while also discussing common types and mechanisms of corrosion. For corrosion-resistant pipe materials currently used in engineering projects, this study provides a detailed comparison of the corrosion resistance, cost-effectiveness, and durability of metal, non-metallic, and composite pipes. It further evaluates the performance of different materials in high-rise residential applications. The findings indicate that careful material selection, optimized construction processes, and effective maintenance management are essential for improving the long-term durability of water supply pipes.
Water supply systems in high-rise residential buildings typically employ zoned or variable-frequency supply methods to meet the varying water pressure requirements across different floors. Under high-pressure conditions, pipes must have sufficient mechanical strength to prevent bursting or leakage. Since valve operations and pump cycling can cause water hammer effects, the pipe material should possess good toughness to withstand impact pressures. Prolonged exposure to water pressure can cause stress corrosion cracking, especially at welded sections, elbows, and joints—areas prone to stress concentration and increased corrosion risk. Water quality in high-rise supply systems directly affects the rate of pipeline corrosion. Low pH levels accelerate the dissolution and corrosion of metal pipes, while high pH levels can lead to carbonate deposits that reduce water flow efficiency. Dissolved oxygen is a key factor driving oxidative corrosion; in oxygen-rich environments, metal pipes—particularly those made of iron or copper—are susceptible to rusting. In some water systems, microorganisms such as sulfate-reducing bacteria may be present. These microbes produce acidic byproducts that accelerate corrosion and contribute to microbiologically influenced corrosion (MIC) of metal materials.
(1) Uniform Corrosion and Localized Corrosion
Uniform corrosion refers to the even chemical or electrochemical degradation of the entire pipeline surface, resulting in a gradual decrease in wall thickness. Although this type of corrosion is generally predictable and manageable, prolonged exposure can weaken the pipeline and increase the risk of leaks. Localized corrosion, by contrast, occurs only in specific areas—such as pipe joints, welds, or surface defects—and typically appears as pitting or crevice corrosion. This type of corrosion is less visible and more hazardous, as it can cause sudden leaks or even perforation of the pipeline.
(1) Electrochemical Corrosion and Microbiologically Influenced Corrosion (MIC)
Electrochemical corrosion occurs due to the presence of electrolytes in water, which create localized potential differences on metal pipe surfaces, leading to electron transfer and the dissolution of metal ions. For example, stainless steel pipes are susceptible to pitting corrosion in chloride-rich water environments, while copper pipes are prone to pitting in low-pH conditions. Microbiologically influenced corrosion (MIC) is caused by bacteria such as sulfate-reducing bacteria, which form biofilms on the inner pipe surfaces. These microorganisms produce corrosive substances like hydrogen sulfide that accelerate the degradation of metal materials. MIC is especially common in underground pipelines or in pipes where water remains stagnant for extended periods.
(3) Synergistic Effects of Mechanical Wear and Chemical Corrosion
In the water supply systems of high-rise residential buildings, the high flow velocity causes continuous erosion of the pipe’s inner walls, particularly at elbows, valves, and other fittings where wear pits may develop and accelerate corrosion. Additionally, chemical components in the water—such as chloride and sulfate ions—can directly react with the pipe material, significantly accelerating the corrosion rate. Under the combined effects of high-velocity flow and aggressive chemical environments, the corrosion rate of pipelines is typically much higher than when either factor acts alone.
Stainless steel contains chromium, which forms a dense, protective chromium oxide layer on its surface, effectively preventing oxidation and corrosion. In low-chloride environments, stainless steel pipes offer corrosion resistance that significantly exceeds that of traditional metal pipes. Stainless steel pipes have high mechanical strength, enabling them to withstand the elevated water pressures typical of high-rise supply systems. They also resist rupture caused by water hammer effects. Suitable for both hot and cold water transport, stainless steel pipes resist deformation and degradation over time. They do not release harmful substances, comply with drinking water hygiene standards, and help ensure water quality safety. In coastal areas or regions with high salt spray and severe metal corrosion, higher-grade stainless steel such as 316L should be used to enhance corrosion resistance. Copper pipes have long been used in water supply systems for their excellent corrosion resistance and natural antibacterial properties. Copper ions possess inherent bactericidal effects, which help inhibit bacterial and microbial growth on the inner pipe walls, thereby reducing the risk of water contamination. In oxidizing environments, copper forms a dense patina that acts as a protective barrier against corrosion. However, in low-pH or high-chloride conditions, copper pipes are vulnerable to pitting and localized corrosion. Copper is well-suited for high-temperature water supply systems, as it resists aging and deformation under prolonged exposure to hot water. In environments with high chlorine levels or acidic water, internal coatings or other anti-corrosion treatments should be applied to extend the service life of copper piping. Galvanized steel pipes were once widely used in traditional water supply systems, but due to their limited corrosion resistance, they have been gradually phased out. These pipes are coated with a layer of zinc that provides initial protection; however, over time, the zinc layer oxidizes and deteriorates, exposing the underlying steel to water and accelerating corrosion. In water with high oxygen content, the dissolution of the zinc coating is accelerated, promoting rust formation and reducing the pipe’s flow capacity. Corrosion and scaling increase the internal surface roughness of galvanized pipes, leading to higher flow resistance and possible deterioration of water quality. Today, galvanized steel pipes have largely been phased out in new construction and renovation projects, remaining in use only for certain industrial applications or non-potable water systems.
Random copolymer polypropylene (PPR) pipe is among the most commonly used materials for residential water supply systems and is widely employed in both hot and cold water distribution. PPR pipes are chemically resistant to acids and alkalis found in water and are immune to electrochemical corrosion and scaling. They comply with drinking water safety standards, do not leach harmful substances into the water, and help maintain water quality. PPR pipes demonstrate good heat resistance, allowing for long-term use at temperatures below 70 °C and short-term exposure up to 95 °C, making them suitable for hot water supply. Installation is straightforward, using hot-melt connections that are strong and durable without requiring metal threads or adhesives. However, compared to metal pipes, PPR pipes have lower rigidity and are more susceptible to external impacts, especially in low-temperature environments where they become brittle. They also tend to expand and deform when exposed to heat, so adequate expansion allowances must be provided for long pipe runs. PPR pipes are ideal for hot and cold water supply in high-rise residential buildings, particularly for indoor plumbing systems. Polyethylene (PE) pipes are widely used in water supply, gas, and drainage systems because of their excellent flexibility and strong resistance to chemical corrosion. PE pipes exhibit strong resistance to acids, alkalis, salts, and various chemical agents, making them suitable for a wide range of water quality conditions. They can accommodate ground movements, such as foundation settlement and earthquakes, without cracking, which makes them especially well-suited for underground installations. PE pipes also exhibit excellent low-temperature performance; even in sub-zero conditions, they retain good toughness and resist cracking, making them ideal for use in cold regions. However, prolonged exposure to sunlight can cause material degradation, so UV protection is necessary for outdoor use. Composite pipes combine the advantages of metal and plastic, providing excellent corrosion resistance, mechanical strength, and ease of installation. These qualities have made them increasingly popular in high-rise residential water supply systems. Aluminum-plastic composite pipes consist of inner and outer polyethylene layers bonded to a central aluminum core, combining the corrosion resistance of plastic with the mechanical strength of metal. Their excellent flexibility allows easy bending during installation, reducing the need for fittings and simplifying construction. However, over time, the aluminum layer may delaminate, weakening the pipe and compromising its long-term durability. Steel-plastic composite pipes consist of a metal core coated with a plastic protective layer on the inner or outer surface to enhance corrosion resistance. These pipes offer high strength and excellent impact resistance, making them suitable for high-pressure water supply systems. They also effectively reduce problems such as scaling and internal corrosion. However, installation demands precise techniques and specific connection methods, such as clamping or threaded joints, to ensure proper sealing and long-term performance.
3. Analysis of the Application of Corrosion-Resistant Water Supply Pipe Materials in High-Rise Residential Buildings
When selecting materials for water supply systems in high-rise residential buildings, compatibility with water quality must be a key consideration. Ideally, materials should resist the effects of dissolved oxygen, pH fluctuations, and microbial activity to minimize corrosion risk. For example, stainless steel and polyethylene pipes offer excellent corrosion resistance and are well-suited for areas with complex or aggressive water quality. Pressure resistance is another critical factor in high-rise applications. Water supply pressures in tall buildings—particularly in upper zones—are often high, requiring pipes that can withstand elevated operating pressures to prevent rupture or leakage. Stainless steel pipes, due to their superior pressure resistance, are well-suited for main pipelines. While random copolymer polypropylene (PPR) pipes are suitable for indoor branch systems, enhanced or thick-walled variants are recommended in high-pressure environments to ensure sufficient strength. In practical construction, ease of connection is crucial to reducing complexity, minimizing installation errors, and improving overall efficiency. PPR pipes are joined using hot-melt techniques, which are straightforward to perform and provide highly reliable connections. Polyethylene pipes can be joined using either hot-melt or electrofusion methods, making them well-suited for underground pipe network installations. In contrast, stainless steel pipes, despite their excellent performance, require more advanced welding or mechanical crimping techniques, which demand skilled labor and increase installation costs. As a result, stainless steel is typically reserved for critical sections of the water supply system rather than being used throughout. To achieve an optimal balance between performance and cost, materials should be selected based on their long-term value rather than solely on initial price. PPR and polyethylene pipes are cost-effective options well-suited for large-scale deployment, while stainless steel—despite its higher initial cost—offers exceptional durability and minimal maintenance, making it a cost-effective choice for high-end residential buildings or facilities requiring long-term operation. Engineering decisions should be grounded in a comprehensive assessment of functional requirements, anticipated service life, and maintenance costs. By carefully weighing these factors, designers and developers can choose the most suitable and cost-effective piping materials for each project.
3.2 Maintenance Strategies for Corrosion-Resistant Water Supply Pipes in High-Rise Residential Buildings
(1) Regular Inspections
In high-rise residential buildings, pipeline systems operate under complex conditions and are exposed to significant fluctuations in water pressure. These factors can compromise the sealing performance at pipe joints and around valves. Regular inspections of these critical areas help promptly identify and address issues such as leaks, damage, or wear. This not only ensures the stable operation of the water supply system but also minimizes the risk of unexpected failures. Inspection tasks should include assessing the external condition of the pipes, verifying pressure gauge readings, and testing valve flexibility and responsiveness.
(2) Water Quality Monitoring
Regular monitoring of key water quality parameters—such as pH, dissolved oxygen levels, and microbial concentrations—is essential for early detection of anomalies and for preventing corrosion resulting from poor water conditions. Water quality monitoring also ensures that harmful substances remain within acceptable limits, supporting compliance with drinking water safety standards. When water quality issues are detected, prompt actions—such as adjusting treatment processes or replacing severely corroded pipes—should be taken to prevent further damage.
(3) Pipeline Cleaning
In hot water systems, scale buildup can significantly reduce pipe flow capacity and may eventually cause blockages, disrupting normal water supply operations. Regular descaling of hot water pipes is particularly important in high-rise buildings, where elevated water pressure and higher flow rates accelerate scale formation. Routine pipe cleaning helps maintain unobstructed flow, reduces the corrosive effects of scale on pipe surfaces, and prevents water quality degradation, thereby enhancing the overall durability of the pipeline system.
(4) Pressure Management
Water supply systems in high-rise buildings must withstand elevated pressures, especially on upper floors where pressure-related issues are more pronounced. Unstable or excessive water pressure can cause water hammer effects, resulting in pipe damage and loosening of joints. Installing pressure regulation devices ensures the system operates within a safe and consistent pressure range, effectively reducing water hammer effects and enhancing the overall safety and reliability of the pipeline network.
Applying a corrosion-resistant coating to the interior surface of pipelines effectively prevents direct erosion caused by water quality. Common lining materials include epoxy resin and polyethylene coatings. These coatings not only enhance the pipeline’s corrosion resistance but can also reduce internal friction in some cases, thereby improving flow stability. With advancements in coating technology, researchers are developing coatings that offer enhanced resistance to high temperatures, acidity, and microbial activity, which are expected to further extend pipeline service life and enhance safety.
Many pipeline corrosion problems arise not from the materials themselves but from construction-related defects—especially inadequate interface preparation and poor-quality welding. Joints and welds are the most vulnerable components of a pipeline system. Therefore, during construction, connection quality must be strictly controlled to ensure welds comply with relevant standards and receive appropriate anti-corrosion treatment. Excessive bending or deformation during installation should be avoided to minimize stress concentrations that can lead to localized corrosion. In high-rise buildings, special attention must be paid to preventing damage or joint loosening caused by elevated water pressure during installation.
Integrating real-time intelligent monitoring systems enables continuous tracking of critical parameters such as corrosion status, temperature, and water pressure. When corrosion or abnormal water quality is detected, the system can promptly alert maintenance personnel to intervene before the issue worsens. Intelligent monitoring not only improves pipeline maintenance efficiency and reduces dependence on manual inspections but also provides early warnings that help prevent failures, thereby ensuring the long-term stable operation of the water supply system.
In summary, this paper analyzes the corrosion challenges faced by water supply pipelines in high-rise residential buildings, explores the types and mechanisms of corrosion, and highlights the impact of factors such as water quality, temperature, and pressure. It also evaluates the performance, advantages, and limitations of commonly used corrosion-resistant pipeline materials—including random copolymer polypropylene (PPR) pipes, stainless steel pipes, and polyethylene pipes—and reviews their current applications in high-rise residential buildings. The study further compares the effectiveness, cost efficiency, and durability of these materials. The implementation of anti-corrosion lining technologies, combined with optimized construction practices and the integration of intelligent monitoring systems, provides a comprehensive strategy to enhance the durability and long-term performance of corrosion-resistant water supply pipelines in high-rise residential buildings.
