Plastic-lined pipe
Plastic-lined pipes offer superior corrosion resistance for demanding industrial applications. These specialized pipes combine the structural strength of metal pipes with the chemical resistance of plastic liners, making them ideal for transporting aggressive chemicals, slurries, and high-purity fluids.
Key Features of Plastic-lined Pipes
- Exceptional corrosion resistance against acids, alkalis, and solvents
- Smooth interior surface minimizes friction and prevents scaling
- High temperature resistance up to 300°F (150°C) depending on liner material
- Available in various sizes from 1/2" to 36" diameters
- Pressure ratings up to 300 psi (20 bar)
- Multiple liner material options including PTFE, PP, PVDF, and PFA
Technical Specifications
| Parameter | Specification |
|---|---|
| Base Material | Carbon steel, stainless steel, or other metals |
| Liner Materials | PTFE, FEP, PFA, PP, PVC, PVDF |
| Size Range | 1/2" to 36" NB |
| Pressure Rating | Up to 300 psi (20 bar) |
| Temperature Range | -20°F to 300°F (-29°C to 150°C) |
| End Connections | Flanged, threaded, grooved, or welded |
Plastic-lined Pipe FAQs
What are the main advantages of plastic-lined pipes over solid plastic pipes?
Plastic-lined pipes combine the structural strength of metal pipes with the chemical resistance of plastic liners. The metal outer pipe provides mechanical strength and pressure resistance, while the plastic liner offers corrosion protection. This combination is more durable than solid plastic pipes in high-pressure applications and more cost-effective than solid corrosion-resistant alloy pipes.
How do I select the right liner material for my plastic-lined pipe?
The liner material should be selected based on chemical compatibility, temperature requirements, and mechanical properties. PTFE offers the broadest chemical resistance but is more expensive. PP and PVC are cost-effective for less aggressive chemicals. PVDF provides good resistance to oxidizing chemicals. Always consult chemical resistance charts and consider the maximum operating temperature when selecting liner materials.
Applications
- Chemical processing plants
- Pharmaceutical manufacturing
- Water treatment facilities
- Mining and mineral processing
- Power generation
- Oil and gas industry
Installation Guidelines
Proper installation is crucial for maximizing the performance of plastic-lined pipes:
- Handle pipes carefully to avoid damaging the plastic liner
- Use appropriate gasket materials compatible with both pipe and fluid
- Follow torque specifications when tightening flanges
- Support pipes adequately to prevent sagging
- Inspect liners regularly for signs of wear or damage
Plastic-lined Pipe FAQs (continued)
What maintenance is required for plastic-lined pipes?
Plastic-lined pipes require minimal maintenance compared to unlined pipes. Regular inspections should check for liner damage, flange leaks, and proper support. The smooth interior surface resists scaling and buildup, but periodic cleaning may be needed for some applications. Always use compatible cleaning agents that won't damage the liner material.
Comparison of Liner Materials
| Material | Max Temp (°F) | Chemical Resistance | Relative Cost |
|---|---|---|---|
| PTFE | 500 | Excellent | High |
| PFA | 500 | Excellent | High |
| PVDF | 300 | Very Good | Medium |
| PP | 200 | Good | Low |
| PVC | 140 | Fair | Low |
Quality Standards
Our plastic-lined pipes meet or exceed the following industry standards:
- ASTM F1545 - Standard Specification for Plastic-Lined Ferrous Metal Pipe
- ASTM D4021 - Standard Specification for Glass-Fiber-Reinforced Polyester Underground Petroleum Storage Tanks
- ASME B31.3 - Process Piping
- ISO 14692 - Petroleum and natural gas industries - Glass-reinforced plastics (GRP) piping