Beneath the city’s surface, a network of ductile iron pipes forms a vital lifeline, tirelessly supplying water day and night. How can we ensure that every pipe leaving the factory is rock-solid and leak-proof? The answer lies in the extremely rigorous water pressure testing process. Today, DINSEN will guide you through an in-depth look at the pressure testing of ductile iron pipes and fittings, adhering to international standards such as EN545, revealing the ultimate pursuit of quality behind it.
Core Mission: Why Conduct Water Pressure Testing?
Water pressure testing is the “ultimate test” for ductile iron pipes and fittings before they leave the factory. Its main purposes are threefold:
- Verifying structural integrity: Ensuring that the pipes withstand the specified pressure without any cracks, permanent deformation, or structural damage.
- Inspecting sealing performance: Checking whether the pipe body, sockets, and other connections are absolutely sealed under pressure, eliminating the possibility of leakage.
- Ensuring long-term safety: Simulating the peak pressure the pipeline may withstand over the next few decades of use, providing users with long-term, reliable safety assurance.
EN545 Standard Testing Procedure Analysis
Based on the authoritative EN545 standard, we present the complete testing process for ductile iron pipes:
- 1. Test Object: Ductile Iron Pipe
- 2. Testing Procedure:
- Steady Pressure Increase: The internal water pressure of the pipe is continuously and steadily increased to the specific working pressure value specified in the standard table.
- Continuous Pressure Holding: After reaching the target pressure, this pressure is maintained for a sufficient period to ensure pressure stability and facilitate comprehensive inspection.
- Precise Timing: The total pressure test cycle time is no less than 15 seconds, of which the holding time at the target test pressure must be no less than 10 seconds.
- Visual Inspection: During the pressure holding period, inspectors will carefully visually inspect the entire pipe body, observing for any leaks, sweating, or abnormal deformation.
- Key Points: These brief few seconds constitute a high-intensity “physical examination” of the pipe material, casting process, and overall structure. Any minute defects will be exposed under high pressure.
Test Procedures for Pipe Fittings and Other Non-Pipe Castings
For pipe fittings with more complex structures, such as elbows, tees, and sockets, EN545 standard also provides rigorous yet flexible test procedures.
Solution A: Hydrostatic Test (Preferred and Commonly Used Method)
The method is basically the same as that for ductile iron pipes, but the required test pressure must comply with the specific requirements for different pipe fittings in the standard table.
This method is intuitive and reliable, and is the most direct way to check the sealing performance of pipe fittings.
Solution B: Pneumatic Test (Manufacturer’s Choice)
For some special shapes or pipe fittings that are not suitable for water testing, manufacturers may choose to conduct a pneumatic test.
Test Pressure: Internal air pressure at least 1 bar (approximately 0.1 MPa).
Pressure Holding Time: Visual inspection time not less than 10 seconds.
Leak Detection Methods: To ensure that even minor leaks are detected promptly, two highly sensitive methods are typically used:
Foam Agent Leak Detection: A special foam agent is evenly applied to the outer surface of the casting. If there is a leak, obvious bubbles will appear at the leak point.
Water Immersion Leak Detection: Completely immerse the casting in water and observe for any air bubbles.
Solution C: Vacuum Test (Equivalent Effect Test)
The manufacturer may also choose a vacuum test that achieves equivalent leak detection results. This method assesses the sealing performance of the casting by detecting the pressure retention under vacuum conditions.
Understanding these stringent testing standards gives you greater confidence. Every ductile iron pipe and fitting from DINSEN undergoes these rigorous tests before leaving the factory. We firmly believe: Safety is the bottom line: We will never overlook even the smallest leak, completely eliminating potential safety hazards before they leave the factory.
Choosing DINSEN means choosing peace of mind and reliability. Let us work together to build an unbreakable defense for the city’s underground arteries.
Post time: Nov-18-2025
