PDCPD Lined Pipe Fittings

PDCPD Lined Pipe Fittings

PDCPD-lined pipe fittings are new composite materials that have been widely used in recent years in the chemical, power, municipal, metallurgical, and mining industries. They offer corrosion resistance, abrasion resistance, high temperature resistance, and impact resistance. They are gradually replacing traditional metal pipes and plastic-lined structures, becoming a key component in fluid transport systems operating under harsh conditions. With increasing demands for pipeline service life, maintenance cycles, and economic efficiency, PDCPD (polydicyclopentadiene) is showing strong growth momentum in various industrial piping systems due to its comprehensive performance and processing advantages.

- PDCPD Introduction
PDCPD (Polydicyclopentadiene) is a thermosetting polymer material made from dicyclopentadiene (DCPD) through addition polymerization. Its unique three-dimensional cross-linked structure imparts excellent mechanical strength and environmental resistance, making it a leading high-performance engineering plastic. Compared to traditional thermoplastics, PDCPD performs better under harsh conditions such as high temperature, high pressure, corrosive media, and strong impact, making it an irreplaceable new structural material in many industrial fields.
PDCPD possesses the following remarkable material properties:
High impact toughness, far exceeding that of thermoplastics such as ABS and PP;
Excellent chemical stability, with strong resistance to corrosive media such as acids, alkalis, salts, and organic solvents;
Excellent thermal stability, with long-term operating temperatures of 90-120°C and short-term resistance to temperatures exceeding 150°C;
Extremely low water absorption, ensuring dimensional and performance stability even in humid or submerged environments;
Excellent dimensional stability and shape retention;
High strength and lightweight properties make it suitable for integrated molding of large structural parts or complex lining components. These properties make PDCPD an ideal material for building reliable fluid systems in industrial environments.

- Definition and Function
PDCPD-lined pipe fittings are products constructed by combining a PDCPD lining with a metal or composite outer shell. They are primarily used to transport highly corrosive, high-temperature, or solid-particle-laden fluids, such as chemical raw materials, highly concentrated acids and alkalis, oils, wastewater, and slurries. Compared to traditional all-plastic or all-metal pipes, PDCPD lining solutions offer both structural strength and corrosion resistance, significantly extending the service life of piping systems and reducing maintenance frequency.
Lined fittings are the connecting and reducing components of the system, including elbows, tees, reducers, flanges, and valve housings. Their inner surfaces, like the straight pipe sections, are lined with PDCPD material to ensure chemical stability and mechanical consistency throughout the system.
Typical lining structures include:
Inner lining: Integrally injection-molded or spray-coated with PDCPD, tightly bonded to the outer structure;
Reinforcement layer: Typically made of carbon steel, stainless steel, or a composite material, providing rigidity and structural support;
Interface sealing system: Ensures sealing and durability at the joints in high-pressure, highly corrosive environments.

- Core Advantages
1. Excellent Corrosion Resistance
PDCPD material can withstand long-term exposure to strong acids (such as sulfuric acid, hydrochloric acid, and phosphoric acid), strong bases (such as sodium hydroxide and potassium hydroxide), and various organic solvents (such as alcohols, ethers, ketones, and esters). Its stable molecular structure resists swelling, immersion, and degradation. Therefore, it has a wide range of applications in the chemical, metallurgical, electroplating, and pharmaceutical industries, far surpassing traditional metal or rubber linings.
2. Impact Resistance
PDCPD is a recognized high-impact polymer that maintains excellent toughness even at low temperatures. This makes it particularly suitable for pipeline systems conveying fluids containing solid particles, prone to crystallization, or high-velocity erosive fluids, effectively preventing the delamination and perforation of traditional lining materials due to impact or abrasion.
3. Excellent Wear Resistance
PDCPD exhibits superior wear resistance when conveying abrasive fluids such as slurries, ore pulp, and crystallization solutions. Its low surface friction coefficient significantly extends its particle erosion resistance life compared to common plastics like PE and PP, effectively extending the life of the pipeline system. 

4. Stable High-Temperature Performance
Unlike conventional thermoplastics, PDCPD, as a thermoset material, does not melt or deform. Even under medium- and high-temperature conditions (above 90°C), it maintains excellent structural strength and physical properties without softening, swelling, or cracking. This makes it suitable for applications involving steam cleaning, high-temperature media, or frequent thermal expansion.
5. Flexible Molding and Strong Adaptability to Complex Structures
PDCPD lining products can be produced through reaction injection molding (RIM) or custom molding techniques to create complex pipe fittings with diverse geometries, such as elbows, tees, and internal threaded joints. This meets the needs of integrated system construction and multi-scenario installation, enhancing industrial automation.
6. Easy Maintenance and High Cost-Effectiveness
PDCPD linings are resistant to cracking, blistering, or peeling, and form a smooth, dense protective film on the surface that resists scaling and is easy to clean. Compared to traditional rubber and fiberglass lining systems, they offer a longer service life, lower maintenance costs, and significantly improved overall economic benefits.

- Application Scenario
1. Chemical Industry
PDCPD-lined pipe and fittings can effectively replace stainless steel, rubber-lined, or fiberglass-lined materials in acid and alkali storage and transportation pipelines, reactor conveying systems, and organic solvent processing equipment. They are particularly suitable for conveying highly corrosive liquid media containing impurities.
2. Metallurgical and Mining Systems
In applications such as slurry transportation, smelting waste liquid treatment, and tailings recovery, the wear and impact resistance of PDCPD lining systems significantly extend pipeline life, reducing safety risks and repair costs caused by corrosion perforation during operation.
3. Power and Flue Gas Desulfurization Systems
Wet flue gas desulfurization (FGD) units in thermal power plants widely use fluids containing strong sulfuric acid, placing high demands on pipeline corrosion resistance. PDCPD linings can handle high concentrations of sulfuric acid and byproduct wastewater, ensuring safe and stable system operation.
4. Wastewater and Environmental Engineering
In environmental protection applications such as industrial wastewater discharge, toxic liquid recovery, and concentrate transportation, PDCPD lining systems provide dual protection against chemical corrosion and contamination, enhancing the environmental friendliness and service life of the entire fluid handling system.
5. Salt Chemical and Pharmaceutical Industries
In industries such as salt production, chlor-alkali, and pharmaceuticals involving highly corrosive salts and organic reactants, PDCPD linings provide safe, contamination-free fluid transport paths, meeting the dual requirements of cleanliness and chemical stability.