Does AL-6XN Meet Controlled Sulfur Requirements of ASTM A270-S2?

Question: If I purchase AL-6XN alloy (N08367) tubing or fittings to the ASTM A270-S2 specification, will they meet the controlled sulfur requirements?

Many end users in the pharmaceutical industry require the ASTM A270-S2 (pharmaceutical quality) tubing for their application. However, sulfur requirements are commonly misunderstood, and the ASTM A270 specification covers several different alloys.

The Supplementary Requirement S2.1.1 states, "When S31600 and S31603 are ordered, sulfur content shall be restricted to the range of 0.005 to 0.017%." This requirement for a controlled sulfur range applies only to S31600 (316ss) and S31603 (316Lss) alloys.

The answer to the question is yes, but the sulfur range for AL-6XN (N08367) is actually 0.030 maximum. The range statement identified in S2 is not applicable to the other alloys identified in this specification.


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