Question. You urgently need a replacement carbon steel valve to handle a sour fluid. You are offered a wrought steel valve with 0.020% sulphur from one supplier and a cast one with 0.026% sulphur from another. Both have hardness below 22HRC, but neither has been HIC tested. What is the position of the standard about accepting these two valves?
a. Neither wrought nor cast is acceptable
b. Wrought is not acceptable but cast is acceptable
c. Wrought is acceptable but cast is not acceptable
d. Both are acceptable
Answer D:
The level of sulfur in the steel is of particular importance, typical maximum acceptable levels for flat-rolled and seamless products are 0.003 % mass fraction and 0.01 % mass fraction, respectively. Conventional forgings with sulfur levels less than 0.025 % mass fraction, and castings, are not normally considered sensitive to HIC or SOHIC
a. Neither wrought nor cast is acceptable
b. Wrought is not acceptable but cast is acceptable
c. Wrought is acceptable but cast is not acceptable
d. Both are acceptable
Answer D:
The level of sulfur in the steel is of particular importance, typical maximum acceptable levels for flat-rolled and seamless products are 0.003 % mass fraction and 0.01 % mass fraction, respectively. Conventional forgings with sulfur levels less than 0.025 % mass fraction, and castings, are not normally considered sensitive to HIC or SOHIC
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