SCH8O/DIN UPVC/CPVC 90° Elbow

How to correctly select UPVC/CPVC 90° elbows? Detailed explanation of pressure level and size standards

In industrial piping systems, UPVC (unplasticized polyvinyl chloride) and CPVC (chlorinated polyvinyl chloride) 90° elbows are key connectors, and their selection directly affects the safety, durability and operating efficiency of the system. Correct selection requires comprehensive consideration of material properties, pressure levels, size standards and special needs of different industries.

1. Material selection: the key difference between UPVC and CPVC
UPVC is suitable for normal temperature (0°C~60°C) and low pressure environment, has good acid and alkali corrosion resistance, low cost, and is often used in safe drinking water (Safe Drinking Water), industrial water treatment (Industrial Water Treatment), ordinary drinking water delivery (Drinking Water) and other scenarios.

CPVC is resistant to high temperatures (up to 93°C~110°C) and has higher compressive strength. It is suitable for high-temperature corrosive media. Typical applications include pickling liquid transportation in the metallurgical industry, high-purity chemical pipelines in the photovoltaic industry, ultrapure water systems in the electronic semiconductor industry, high-temperature sterilization pipelines in the medicine industry, radiation-resistant pipelines in nuclear power plants, and chemical corrosion environments in industrial wastewater treatment.

2. Pressure grade selection (PN and SCH standards)
The pressure bearing capacity of the elbow depends on the wall thickness grade. Common pressure standards include PN (nominal pressure, such as PN6, PN10, PN16) and SCH (Schedule, such as SCH40, SCH80).

For safe drinking water and ordinary water treatment, UPVC material is usually selected, and the pressure grade PN6~PN10 can meet the needs. In the industrial wastewater and metallurgy industries, due to the strong corrosiveness of the media, it is recommended to choose PN10~PN16 or SCH80 CPVC elbows to ensure long-term pressure resistance and chemical corrosion resistance.

Photovoltaic, electronic semiconductor and medicine industries have extremely high requirements for pipeline cleanliness and chemical resistance, and usually use CPVC SCH40 or SCH80 elbows to ensure that high-purity media are not contaminated. Nuclear power plant applications require special radiation-resistant CPVC materials that meet strict standards such as ASME NQA-1.

3. Size Standards (DN and Inches)
The size of the UPVC/CPVC 90° elbow must match the piping system. Common standards include metric (DN15, DN50, DN100, etc.) and imperial (1/2", 2", 4", etc.).

In the electronic semiconductor and photovoltaic industries, small-diameter elbows (DN15~DN50) are usually used due to the need for high-precision fluid control. Large-diameter elbows of DN80~DN300 are commonly used in industrial wastewater treatment and metallurgical industries due to large flow rates. Nuclear power plants and the pharmaceutical industry must strictly follow industry standards to ensure accurate size matching to avoid leakage or contamination risks.

4. Industry-specific certifications and requirements
Different industries have different certification requirements for elbows:
Safe Drinking Water / Drinking Water: Must comply with NSF/ANSI 61 food safety certification.
Electronic Semiconductor / Photovoltaic: Requires ultra-smooth inner wall to reduce particle deposition, and some applications require SEMI F57 certification.
Medicine: USP Class VI or FDA standards must be met to ensure that no plasticizer is leached.
Nuclear Power: ASME NQA-1 quality certification must be passed and radiation-resistant modified CPVC materials must be used.

5. Installation and maintenance recommendations
Connection method: UPVC/CPVC elbows are usually bonded with solvents (PVC glue). During installation, ensure that the interface is clean and free of oil.
Support spacing: High-temperature (CPVC) or large-diameter pipes require additional support frames to avoid deformation due to thermal expansion or fluid impact.
Regular inspection: In high-risk industries such as chemical and nuclear energy, elbows must be regularly inspected for signs of cracks, aging or corrosion, and damaged parts must be replaced in a timely manner.