PLS 1 VS. PLS 2 API 5L materials for line pipe

[engr2GW]

Hi,

for liquid gathering pipe (ASME B31.4), API 5L materials are listed, but there was a foot note that recommends the PLS 2 types. apart from a little variation in the chemistry (which I don't understand quite well).
My questions are:
1. is PLS 2 grade B?
2. I believe that PLS 2 is group 1 and P 1(with respect to welding)?
3. a welding procedure qualified for A106 grade B and API 5L X-42, X-46, and X-52, can it be used to also weld the PLS 2 designation (X-42N, X-46N, and X-52N)?
4. hardness testing is one of the ways that can be used to NACE qualify a welding procedure by controlling hardness, is the hardness survey was done on and qualifies A106 grade B and API 5L X-42, X-46, and X-52, can it also be used for the PLS 2 designation (X-42N, X-46N, and X-52N)?
5. is chemistry the only difference between PLS 1 AND 2? because most of the mechanical properties are similar/same.

thanks for your response.

As much as possible, do it right the first time...

 

[DVWE]

First of all, have you thoroughly reviewed API specification 5L? Also, ASME Section IX?

1. No. PSL 2 will be either BR, BN, BQ, or BM. Only PSL 1 can be Grade B. See Table 1 of API 5L.
2. No. See ASME Section IX, QW-422. Find the API 5L list.
3. Yes. See ASME Section IX, QW-422.
4. Not necessarily, because the PSL 1 designations (X42, X46, and X52) can be normalized, normalized and tempered, or quenched and tempered per Table 1 (as well as the other conditions listed). The PSL 2 designations (X42N, X46N, and X52N) are either normalized, or normalized and tempered (as well as the other conditions listed). My opinion is for WPS qualification, they need to be in the same heat treated condition.
5. No, there are other differences such as tensile RANGES for PSL 2, CVN testing for PSL 2. See the API specification 5L.