WBPSC AE (MCD) 1998
⭕ A. 3 kg/cm²
⭕ B. 5 kg/cm²
⭕ C. 7 kg/cm²
⭕ D. 10 kg/cm²
📚 Explanation:
Cast iron pipes can be subjected to a maximum safe working pressure of 7 kg/cm².
🔹 Cast iron has good compressive strength but limited tensile strength.
🔹 Excess pressure may lead to cracking due to brittle nature.
🔹 Therefore, 7 kg/cm² is taken as a safe design limit.
Cast iron pipes can be subjected to a maximum safe working pressure of 7 kg/cm².
🔹 Cast iron has good compressive strength but limited tensile strength.
🔹 Excess pressure may lead to cracking due to brittle nature.
🔹 Therefore, 7 kg/cm² is taken as a safe design limit.
👉 Therefore, the correct answer is: C. 7 kg/cm²
Key Points on Cast Iron Pipe Pressure:
- CI pipes are brittle: High pressure may cause cracking.
- Safe limit: Maximum operating pressure ≈ 7 kg/cm².
- Above 7 kg/cm²: Thick-walled or ductile iron pipes are preferred.
