1. Q: What non-destructive testing (NDT) methods are critical for these pipes?
A: Ultrasonic Testing (UT) for internal flaws, Magnetic Particle Testing (MPT) or Dye Penetrant Testing (DPT) for surface cracks, and often hydrostatic pressure testing for pressure applications.
2. Q: What are the potential temper embrittlement risks?
A: Like many low-alloy steels, improper tempering in a critical temperature range (e.g., 250-400°C) can reduce toughness. Following correct tempering procedures is crucial.
3. Q: How does the hardenability of 20MnV6 compare to 20MnV?
A: 20MnV6, with its controlled Boron content, is specifically designed for higher hardenability, ensuring greater depth of hardening in thicker sections compared to standard 20MnV.
4. Q: What corrosion resistance can be expected?
A: They are not stainless steels. They have moderate corrosion resistance similar to carbon steels and require protective coatings (painting, plating, galvanizing) for corrosive environments.
5. Q: Are these materials suitable for sour service (H2S environments)?
A: Generally not recommended for severe sour service without special heat treatment and stringent hardness control (typically below HRC 22) to prevent Sulfide Stress Cracking (SSC). Specific grades like L80 types are better suited.
