SA-106-B Normalized
SA-106-B Normalized
(OP)
Sorry to anyone who read this already, I also posted in the Vessel forum.
Is there any merit in normalizing SA-106-B?
I'm on a job now where the request is as per above for use on vessels subject to sulfide stress cracking. I've heard people say that SA-106-B has no merit to normalizing as it will not move it from curve B material to curve C material as per UCS-56, as UCS-56 indicates not only a normalizing requirement but also a 'fine grain practice' requirement. ASME defines 'fine grain practice' as it applies to SA-20 as per interpretation VIII-1-92-100, SA-20 is a plate spec and would therefore not apply to SA-106-B. We could probably all agree that you could normalize it, normalizing is really a heat treatment and anything (within reason) can be heat treated.
So, if someone requests SA-106-B normalized, does this request have any value?
Is there any merit in normalizing SA-106-B?
I'm on a job now where the request is as per above for use on vessels subject to sulfide stress cracking. I've heard people say that SA-106-B has no merit to normalizing as it will not move it from curve B material to curve C material as per UCS-56, as UCS-56 indicates not only a normalizing requirement but also a 'fine grain practice' requirement. ASME defines 'fine grain practice' as it applies to SA-20 as per interpretation VIII-1-92-100, SA-20 is a plate spec and would therefore not apply to SA-106-B. We could probably all agree that you could normalize it, normalizing is really a heat treatment and anything (within reason) can be heat treated.
So, if someone requests SA-106-B normalized, does this request have any value?





RE: SA-106-B Normalized
Normalizing as a separate heat treatment step for this plate will result in a more uniform grain size and slightly better ambient temperature strength. Note that I stated ambient temperature service, not elevated temperature service. That is it - I see no reason to specify normalizing for SA 106 material, considering this material by specification is for elevated temperature service.
RE: SA-106-B Normalized
RE: SA-106-B Normalized
RE: SA-106-B Normalized
we refuse to go to the hassle of normalizing small pieces of pipe and running new physical tests for something that adds no value because someone asks for it.
it is normally because some "expert" thinks that if the plate is normalized, that everything that touches that plate, internal or external, pressure or non-pressure, should be normalized.
if they insist, we offer a-333 pipe
if they don't want that,or some other normalized pipe.. sorry.
RE: SA-106-B Normalized
Steve Jones
Materials & Corrosion Engineer
http://www.pdo.co.om/pdoweb/
RE: SA-106-B Normalized
It is being considered to get acceptable charpy values (17/12 ft-lbs @ 0 deg F) from A106-B. Other material options are not available in sizes needed.
It appears the critical variable to get acceptable charpy values from A106-B is the Mn level. The higher the Mn the higher the charpy.
Has anyone verified or disproved this statement?
Would NQT or QT yield better charpy values than normalizing?
RE: SA-106-B Normalized
is this pipe over 1" thick?
RE: SA-106-B Normalized
What are the current absobed energy values? It is quite possible that normalizing will prove effective. Appropriate normalizing will refine the current grain structure. I have often seen a 20 F delta due to normalizing in both A-106 and A-105 - even greater through double normalizing.
RE: SA-106-B Normalized
SA-106 Grade B pipe material is permitted for use down to -20 deg F by ASME B&PV Code without having to conduct impact tests for material thickness 3/8" or less. This means that for lower temperature service conditions, SA 106 Grade B that is 3/8" or less posses adequate notch toughness to satisfy 15 ft-lbs at -20 deg F (using Curve B as shown in Figure UCS-66). You can normalize until the cows come home and you will not gain relief from the impact exemption curve because you need both a fine grain practice AND N&T or N heat treatment.
RE: SA-106-B Normalized
RE: SA-106-B Normalized
Keep in mind that Grade B has by specification 0.30% C max, and this will be your limiting factor for notch toughness at lower temperatures for material that is not fine grain.
RE: SA-106-B Normalized
I have seen absobed energy values of 17/12 at 0 F in the hot formed condition of A-106 B. I have also seen the same values between 32 F an 40 F. I recommend that you determine what the absorbed energy values are in the pipe now at at 0 F before normalizing or define the transition temperature of the material, unless you do not have adequate material for conducting the tests.
If insufficient material exists, I recommend that you double normalize, test and hope for the best.
RE: SA-106-B Normalized
My supplier has contacted the mill and found that impact values in excess of our needs are obtain consistently when the available material is normalized, quenched and tempered. That procedure is currently being tested on a 6" sample of the 2-1/2" wall thickness A106-B tubing.