UPVC Pipes
About Rendifield UPVC Pipe
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Enhancing PVC Pipe Properties Through Advanced Manufacturing
PVC is a versatile and durable material, and its unique properties can be further enhanced through the addition of specialised additives. These additives allow the production of strong, tough, and application-specific pipe materials, such as:
- Modified PVC for improved strength and flexibility
- Foamed multilayer sewer and drainage pipes for reduced weight and enhanced efficiency
- Weather-resistant above-ground drainage pipes for long-lasting outdoor applications
Additives and Production Process
During the manufacturing process, essential additives, including heat stabilisers, lubricants, and performance enhancers, are mixed into the raw PVC material. This mixture is created in a high-speed mixer, forming a dry blend that is specially formulated for the pipe extrusion process.
The production process includes:
- Extrusion: The dry blend is fed into an extruder, where a combination of heat and mechanical shear converts it into a homogeneous molten mass.
- Shaping: The molten material is passed through a die and calibrator, creating pipes with precise tolerances for diameter, wall thickness, and mechanical properties.
Environmentally Friendly Advancements
In recent years, manufacturers have shifted from lead-based heat stabilisers and lubricants to more environmentally friendly alternatives, such as organic compounds and calcium/zinc-based stabilisers. This change has improved the sustainability and safety of PVC pipe production.
Proven Performance by Rendifield
For over 15 years, Rendifield Mining and Industrial Piping Solutions has provided reliable, cost-effective, and energy-efficient PVC piping across Southern Africa, Australia, and New Zealand. This success is due to the material’s long-term safety and performance benefits.
The Importance of Toughness and Safety Factors
PVC’s toughness, defined by its resistance to impact and crack propagation, is critical in ensuring long-term reliability. Toughness prevents cracks from forming during handling, installation, or service and also prevents small cracks from spreading through the pipe wall.
Unlike brittle materials that fail unpredictably, tough materials fail predictably through controlled ductile yielding, allowing for the use of lower long-term safety factors. For example:
- PVC-U offers a balance of strength and toughness, allowing lower safety factors while maintaining durability.
- HDPE, which has lower strength but higher toughness than PVC, uses a safety factor of 1.25.
Accepted by Pipe Standards Authorities
Modern pipe standards and the water industry now recognise that a 50-year safety factor is influenced by both the strength and toughness of the material. This predictable performance allows for the efficient design and safe long-term use of Rendifield’s PVC piping solutions in various applications, reducing costs and ensuring reliable infrastructure.
UPVC Pipe composition
Polyvinyl Chloride (PVC) is one of the most versatile and widely used pipe materials, valued for its durability, chemical resistance, and cost-effectiveness. PVC is produced through the polymerisation of vinyl chloride, which is derived from coal (or oil) and common salt. Remarkably, salt accounts for over 50% of the polymer composition, making PVC one of the most environmentally friendly plastics, as it is less dependent on depleting hydrocarbon resources.
Enhancing PVC Properties with Additives
PVC’s performance can be further improved by incorporating special additives to create stronger and more durable pipe materials, including:
- Modified PVC (PVC-M) – Offers enhanced strength and impact resistance.
- Foamed multilayer sewer and drainage pipes – Lightweight and optimised for underground applications.
- Weather-resistant above-ground drainage pipes – Designed to withstand UV exposure and environmental factors.
In addition to these performance-enhancing additives, heat stabilisers and lubricants are essential in the extrusion process. These components are blended with the raw PVC material in a high-speed mixer, forming a dry blend specifically formulated for pipe manufacturing.
Manufacturing Process
- Extrusion – The dry blend is fed into an extruder, where a combination of heat and mechanical shear transforms it into a homogeneous molten mass.
- Shaping – The molten material is passed through a die and calibrator, ensuring precise control over diameter, wall thickness, and mechanical properties.
Environmentally Friendly Advancements
In recent years, lead-based heat stabilisers and lubricants have been replaced with more sustainable alternatives, such as organic compounds and calcium/zinc-based stabilisers. This transition enhances the environmental safety of PVC production, aligning with modern industry standards for sustainable infrastructure development.
With its strong, lightweight, and adaptable composition, PVC remains an ideal choice for a wide range of municipal, industrial, and construction applications.
UPVC Pipe physical properties
(All tables are best viewed in tablet-mode or on a computer/laptop)
The unique properties of PVC can be further improved through the addition of specialised additives, creating stronger and tougher pipe materials for various applications. These enhancements enable the production of:
- Modified PVC (PVC-M) – A more impact-resistant and durable version of standard PVC.
- Foamed multilayer sewer and drainage pipes – Lightweight and optimised for underground use.
- Weather-resistant above-ground drainage pipes – Designed to withstand UV exposure and environmental factors.
Manufacturing Process & Material Enhancements
To ensure optimal extrusion and processing, essential additives such as heat stabilisers and lubricants are blended with raw PVC material in a high-speed mixer, forming a dry blend specifically formulated for pipe extrusion.
- Extrusion Process – The dry blend is introduced into an extruder, where heat and shear force transform it into a homogeneous molten mass.
- Pipe Formation – The molten material passes through a die and calibrator, ensuring precise control over the pipe’s outside diameter, wall thickness, and mechanical properties.
Environmentally Friendly Material Improvements
In recent years, lead-based stabilisers and lubricants have been replaced with more sustainable alternatives, including organic compounds and calcium/zinc-based stabilisers. These advancements make PVC safer and more environmentally friendly while maintaining high performance and durability.
Proven Reliability & Efficiency
For over 15 years, Rendifield Mining and Industrial Piping Solutions has been successfully used in Southern Africa, Australia, and New Zealand, proving to be one of the most cost-effective and energy-efficient piping materials available. This efficiency is due to the lower long-term safety factor required when using tough, impact-resistant materials.
Understanding Toughness & Long-Term Safety
Toughness in PVC pipes is defined by their resistance to impact and crack formation. This characteristic prevents crack initiation and stops cracks from spreading through the pipe wall, ensuring a longer service life.
Cracks or notches can develop due to handling, installation, or service stresses, such as bending forces and point loads on the pipe. However, tough materials fail in a predictable ductile manner, unlike brittle materials that can fail unexpectedly. The relationship between toughness and long-term safety is well established:
- PVC-U (Unplasticised PVC) offers a balance of strength and toughness, allowing for lower safety factors.
- HDPE (High-Density Polyethylene) has higher toughness but lower strength than PVC-U, resulting in a safety factor of 1.25.
Industry Standards & Performance Considerations
Pipe standards authorities and the water industry now recognise that the 50-year safety factor is influenced by both strength and material toughness. Tough materials allow for predictable performance over time, reducing the need for excessive safety margins.
As with all thermoplastic materials, PVC pipe properties depend on operating temperature and the duration of stress application. When pipes are used at higher temperatures, the working pressure should be adjusted accordingly, either by reducing the operating pressure or selecting a higher pressure class to maintain the long-term design life of the pipeline.
With its proven durability, energy efficiency, and adaptability, PVC piping remains a leading choice for municipal, industrial, and infrastructure applications, offering long-term reliability and cost savings.
| PHYSICAL | UNITS | PVC-U | PVC-M |
| Co-Efficient of Linear Expansion | k-1 | 6 X 10-5 | 6 X 103 |
| Density | Kg/m3 | 1.4 X 103 | 1.1.J X 103 |
| Flammability [oxygen index] | % | 45 | 45 |
| Shore Hardness [DJ | 70-80 | 70-80 | |
| Softening Point [Vicat- minimum] | “C | > 80 | > 80 |
| Specific Heat | J/Kg/K | 1.0 X 103 | 1.0 X 103 |
| Thermal Conductivity [D”C-SO”C] | W/m/K | 0.14 | 0.14 |
| MECHANICAL | |||
| Elastic Modulus [long term: 50 years] | MPa | 1500 | 1400 |
| Elastic Modulus [short term: 100 seconds] | MPa | 3300 | 3000 |
| Elongation at break [Minimum] | % | 45 | 45 |
| Poisons Ratio | 0.4 | 0.4 | |
| Tensile Strength [50 year – extrapolated] | MPa | 26 | 26 |
| Tensile Strength [short-term / Minimum] | MPa | 45 | 45 |
| FRICTION FACTORS | |||
| Manning | 0.008-0.009 |
0.008-0.009
|
|
| Hazen Williams | 150 |
150
|
|
| Nikuradse Roughness [k] | mm | 0.03 | 0.03 |
UPVC Pipe Applications
Water supply
Below-ground pressure applications for the conveyance of potable water in reticulation systems and for other applications in which continuous temperatures in excess of 25 °C are not encountered
SANS 1283 High Impact – Suitable for the conveyance of nonpotable water at temperatures between 5 °C and 50 °C for underground use in mines
Drainage pipes
Above ground drainage
SEWAGE
Sewerage under pressure
UPVC pipe dimensions
UPVC Features
Environment-friendly & Lead free material
Durability and toughness
Resistant to acids and alkalis
Resistant to abrasion, scouring and modern cleaning methods
Inflammable: Does not support
UPVC Benefits
Excellent flow characteristics: reduces friction losses
Best long-term strength [serves in excess of 50 years)
Long-term strength, toughness and stiffness
Large bore and high flow capacity
Light mass: for easy handling and installation
Elastomeric locked-in sealing ring system
