Journeyman Plumber ExamWater Supply SystemsMedium
A plumber is installing a water distribution system in a new commercial building. The design calls for a main water service line that must withstand high pressures and be highly resistant to corrosion and physical damage, as it will be buried under heavy vehicle traffic areas. Which pipe material is best suited for this application?
- APEX (Cross-linked Polyethylene)
- BType M Copper
- CPVC (Polyvinyl Chloride)
- DDuctile Iron
Show answer & explanationAnswer & explanation
Correct answer: D. Ductile Iron
Ductile iron pipe is renowned for its exceptional strength, durability, and resistance to high pressures, corrosion, and external loads, making it ideal for buried water mains in heavy traffic areas where other materials might fail.
Why the other options are wrong
- A. PEX is flexible and corrosion-resistant but is generally not used for main water service lines under heavy traffic due to its lower crush resistance compared to metallic pipes.
- B. Type M copper is a thinner-walled copper pipe, generally not suitable for high pressure, heavy traffic, or direct burial applications without significant protection.
- C. PVC pipe can be used for water service but may not offer the same level of impact resistance or strength as ductile iron for heavy traffic areas and can become brittle in cold temperatures.
Ductile Iron Pipe
A strong and durable pipe material, commonly used for municipal water mains and large commercial service lines, known for its high pressure rating and resistance to external loads and corrosion.
- High strength and durability
- Excellent pressure rating
- Resistant to external loads (e.g., traffic)
- Good corrosion resistance with proper coatings
Memory trick: Heavy traffic? Ductile iron's the magic!