The Application Scope of PVC-O Pipes

Here is a detailed translation of the application scope of PVC-O pipes, elaborating on specific requirements, technical parameters, and application cases across different industries:

I. Municipal Engineering Sector

1. Urban Water Supply Systems

Pressure Rating: Operating pressure ranges from 0.6 to 2.0 MPa, meeting the high-pressure demands of water supply for high-rise buildings and long-distance water transmission (e.g., water from suburbs).
▶ Case Study: A coastal city renovated its aging water supply network with DN600 PVC-O pipes (pressure rating 1.6 MPa), replacing cast iron pipes. The leakage rate dropped from 15% to below 3%, and the pipes resisted seawater backflow corrosion.

Safety: The material contains no heavy metals and complies with GB/T 17219 drinking water hygiene standards, eliminating risks of water contamination.

Construction Advantages: Weighing only 1/5 of cast iron pipes, they can be heat-fused or electro-fused, shortening installation time by 30% for the same pipeline length.

2. Drainage and Sewage Treatment Systems

Corrosion Resistance: Withstands sewage with pH 2–12 (e.g., industrial wastewater mixed with municipal sewage), preventing long-term corrosion and perforation.
▶ Case Study: A chemical park used DN800 PVC-O pipes for industrial wastewater containing hydrochloric acid (concentration ≤5%). The service life reached 15 years, far exceeding the 8–10 years of ordinary PVC-U pipes.

Settlement Resistance: Flexible joints accommodate uneven foundation settlement (allowing axial displacement of ±15 mm and angular displacement of ±3°), reducing cracking risks.

Hydraulic Performance: The inner wall roughness is n=0.009 (lower than n=0.014 for concrete pipes), increasing drainage flow by 20% and reducing waterlogging risks.

II. Industrial Sector

1. Chemical Fluid Transportation

Medium Compatibility:

Strong Acids: Suitable for sulfuric acid (concentration ≤70%), nitric acid (concentration ≤50%), etc.;

Strong Bases: Withstands sodium hydroxide (concentration ≤40%), potassium hydroxide, etc.;

Others: Brine, electroplating solutions, printing/dyeing wastewater.
▶ Comparison: Under the same conditions, PVC-O pipes cost only 1/3–1/2 of stainless steel pipes and require no welding or anti-corrosion coating.

Temperature Range: Short-term resistance up to 60°C (long-term ≤45°C), suitable for most room-temperature chemical processes.

2. Food and Pharmaceutical Industries

Hygiene Standards: Certified by FDA, suitable for direct contact with food-grade fluids (e.g., beer wort, pharmaceutical purified water).
▶ Case Study: A beverage factory replaced pipes in its filling workshop with DN100 PVC-O pipes for conveying carbonated beverage syrup. The smooth inner walls reduced residue, extending cleaning cycles from twice a week to once a week and improving productivity.

Anti-Microbial Adhesion: Surface smoothness reaches Ra≤0.8μm, minimizing bacterial growth and meeting GMP cleanroom requirements.

3. Industrial Circulating Water Systems

Anti-Scaling Performance: At a flow rate ≥1.5 m/s, calcium carbonate deposition is 80% lower than in steel pipes, reducing chemical descaling frequency (saving ~40% in chemical costs).
▶ Data: After 5 years of use in a power plant's cooling water network, the inner wall scale thickness of PVC-O pipes was only 0.2 mm (1.5 mm for steel pipes over the same period).

III. Power and Communication Engineering

1. Cable Protection Pipes

Insulation Performance: Volume resistivity ≥1×10¹³ Ω·m, breakdown voltage ≥20 kV/mm, suitable for electromagnetic environments of 110 kV high-voltage cables.
▶ Application: A city's high-voltage grid renovation used DN150 PVC-O pipes as casings for 110 kV cables buried 1.5 m deep. After 10 years of operation, no leakage or casing damage occurred.

Impact Resistance: Withstands beat by 10 t trucks ( ≥12.5 kN/m² per GB/T 9647), suitable for laying under municipal roads.

2. Utility Tunnel Applications

Multi-Pipeline Integration: Can be laid in the same compartment as thermal pipes (with thermal insulation) and gas pipes, complying with GB 50838 utility tunnel design standards.
▶ Case Study: In a new district's utility tunnel project, PVC-O pipes as communication cable casings were installed in the same compartment as natural gas pipes with a 0.5 m spacing, passing fire safety inspections.

IV. Agricultural and Water Conservancy Projects

1. Farmland Irrigation Systems

UV Resistance Design: Added 2.5% nano-grade carbon black ensures an outdoor service life of 50 years (retaining ≥85% tensile strength after 5000 h of UV aging testing per GB/T 16422.2).
▶ Case Study: A cotton field in Xinjiang used DN63 PVC-O pipes for drip irrigation. After 8 years of outdoor use, no aging or cracking occurred, and irrigation water utilization increased from 60% to 85%.

Topographic Adaptability: Can bend along terrain (minimum bending radius 25D, D=pipe diameter), reducing elbow usage and head loss.

2. Rural Safe Drinking Water Projects

Cost Advantage: For the same pressure rating, DN100 PVC-O pipes cost ~35 RMB/m, lower than PE pipes (~45 RMB/m) and ductile iron pipes (~60 RMB/m).
▶ Data: A mountainous rural water supply project using DN50–DN200 PVC-O pipes saved 18% in total investment compared to a PE pipe scheme.

3. Water Conservancy Water Transmission Projects

Foundation Deformation Resistance: Allows settlement of up to 300 mm in soft soil foundations (adjusted via flexible joints), preventing rigid pipe fractures.
▶ Case Study: A reservoir water transmission pipeline in Southwest China crossed karst terrain using DN1200 PVC-O pipes. After 5 years and three earthquakes below magnitude 4, no pipeline damage occurred.

V. Mining and Quarrying Engineering

1. Slurry and Tailings Transportation

Abrasion Resistance Test: Per ASTM G75 erosion testing, the wear rate for slurry containing quartz sand (particle size ≤2 mm) is only 0.05 g/m² (0.15 g/m² for ordinary PVC-U pipes, 0.3 g/m² for steel pipes).
▶ Case Study: A copper mine's tailings pipeline (transporting 35% concentration slurry at 2.5 m/s) used DN400 PVC-O pipes with a service life of 10 years (standard steel pipes last only 3–5 years).

Impact Resistance Design: Withstands occasional impacts from large stones in slurry (impact energy ≤50 J), preventing pipeline rupture and tailings leakage.

2. Underground Ventilation and Drainage

Anti-Static Treatment: Special formula pipes have surface resistivity ≤1×10⁶ Ω, meeting explosion-proof requirements for mines (e.g., gas mines).
▶ Application: A coal mine used DN300 anti-static PVC-O pipes for underground drainage, connected via flanges, with a drainage capacity of 200 m³/h. No electrical leakage issues occurred in 5 years of operation.

VI. Special Scenarios

1. High-Seismic Risk Areas

Seismic Performance: Passed ISO 13679 earthquake simulation testing, with ≤5 mm joint displacement and no leakage under 8-degree seismic intensity.
▶ Case Study: After the Wenchuan earthquake, a county's water supply network in post-disaster reconstruction used PVC-O pipes. No damage was detected after a magnitude 6 aftershock in 2022.

2. Trenchless Construction Scenarios

Traction Capacity: Maximum allowable traction stress ≤20 MPa, enabling long-distance trenchless laying (single traction length up to 500 m).
▶ Case Study: A sewage pipe crossing a river in an urban area used DN800 PVC-O pipes via pipe jacking, with a crossing length of 300 m and a construction period 40% shorter than open-cut methods.

3. Marine Engineering and Salt Industry

Seawater Corrosion Resistance: After soaking in seawater with 35 g/L NaCl for 1000 h, tensile strength decreased by ≤5% (per GB/T 10703 salt spray testing).
▶ Application: A coastal salt farm used DN500 PVC-O pipes for brine transportation (25% NaCl solution). After 10 years, no corrosion or perforation occurred, reducing costs by 25% compared to traditional FRP pipes.

VII. Specification Selection and Design Recommendations

1. Pipe Diameter and Pressure Rating Matching

2. Environmental Adaptation Design

High-Temperature Areas: Add 0.3% antioxidant to increase long-term temperature resistance to 50°C (e.g., South China);

Cold Regions: Use -20°C freeze-resistant formula with low-temperature impact performance reaching TIR≤5% (e.g., Northeast and Northwest China);

Strong UV Areas: Increase carbon black content to 3.0% to delay aging (e.g., Tibetan Plateau).

VIII. Comparative Advantages Over Other Pipe Materials

Conclusion: PVC-O pipes break through the performance limitations of traditional PVC pipes via molecular orientation, demonstrating significant advantages in high-pressure, corrosive, abrasive, and complex geological scenarios. They also offer environmental and economic benefits, making them an ideal choice for pipeline systems across multiple industries. In practical applications, precise selection should be based on engineering standards (e.g., Technical Code for Buried Plastic Drainage Pipeline Engineering CJJ 143) and third-party test reports (e.g., ring stiffness, hygiene performance).