Stoneware (vitrified clay) pipes: Which of the following is NOT a correct characteristic for stoneware pipes used in gravity sewers?

Introduction / Context:
Stoneware (vitrified clay) pipes are a traditional choice for small gravity sewers and house connections because of chemical resistance and a smooth glazed bore. However, their brittle nature and jointing make them unsuitable as pressure pipes.

Given Data / Assumptions:

• Application is primarily gravity sewerage.
• Glazed, low-absorption vitrified body.
• No internal pressure service expected.

Concept / Approach:

In gravity flows, hydraulic roughness is low and sulphide corrosion resistance is high, favoring stoneware. Pressure service demands tensile strength, flexible joints, and pressure-rated integrity; materials like ductile iron, PVC, HDPE are typically chosen for pressure duties.

Step-by-Step Solution:

Verification / Alternative check:

Standards for vitrified clay pipes specify non-pressure applications; pressure ratings for clay are not standard practice.

Why Other Options Are Wrong:

(a)–(c) are correct traits of stoneware in gravity service; only (d) mischaracterizes usage.

Common Pitfalls:

Using stoneware in areas prone to differential settlement; inadequate flexible joints; assuming it can withstand internal pressure surges.

Final Answer:

Specially suited to pressure-pipe applications