This specification covers seamless carbon steel pipe for high-temperature service in NPS 1/8 to NPS 48 inclusive, with nominal (average) wall thickness as given in ASME B 36.10M. It shall be permissible to furnish pipe having other dimensions provided such pipe complies with all other requirements of this specification. Pipe ordered under this specification shall be suitable for bending, flanging, and similar forming operations, and for welding. When the steel pipes are to be joined together, it is presupposed that a welding procedure suitable to the grade of steel and intended use or service will be utilized.
Common uses include pressure piping at high temperatures (piping for water, air or steam, etc.). Though the product is described as for “high temperatures”, ASME allows for use as low as -20F (-29C). It can be used upwards of 800F (427C), though the SA106 allowable stresses drop significantly above 400F (200C).
Note that A106 allows only seamless pipe manufacturing techniques. This means that you will never see ERW/HFIW or DSAW A106 pipes.
This ASTM specification is written so that the end user and the manufacturer can agree upon, and clearly understand, the properties and capabilities of the piping product being supplied. In contrast with national codes (like API, ASME or CSA), ASTM A106 is rarely stipulated by national or state-level legal requirements.
Rather than “re-invent the wheel”, ASME has recognized the widespread use of this product, and has adopted the A106 standard for use in pressure vessel (BPVC) and pressure piping (B31.X) applications. The details of this can be found in ASME Boiler and Pressure Vessel Code (BPVC) Section IIA, and is identified as SA106. Note that there may be minor exceptions in the SA version of ASTM standards, and the engineers, end users, purchasers and Manufacturer must comply. Note also that there is often a 5 to 10 year lag between the approved ASTM edition and the approved ASME edition. This means that there can be minor differences between the two specifications. Most engineers who spec SA106 product will also prefer to follow the requirements of the more recent ASTM version (which is usually also more strict), resulting in the common notation ASTM/ASME A/SA106 on the product documentation.
Note that there is a lower limit on manganese (Mn) in ASTM A106 of around 0.30% Mn, though you will typically see at least twice this much (around 0.60% Mn). For products that are hot rolled, it will be more common to see values of 0.80 to 1.20% Mn, as the increased alloying is necessary to attain the strength requirements of the standard. Because of these considerations, this product will commonly have a Mn/C ratio of 3 to 5 depending on the production method. Therefore, ASME B31.3 limits the low temp application of SA106 Grade B products to above -20F (-29C). That being said, for lower temp applications approaching -20F, many engineers may choose to spec specific low-temp products (such as SA333) for these applications.
A106 does not have its own table of pipe dimensions. Rather, like A333 and API 5L, it reverts to ASME B36.10 for the nominal pipe dimensions. Therefore, A106 pipe products are often multi-certified to similar ASTM A53, A333 and API 5L grades, where the requirements of all these specifications are met.
Note that for welding SA106 products, ASME BPVC Section IX considers SA106 GrB to be in the P1G1 alloy grouping (along with SA53 GrB, SA333 Gr6), while SA106 GrC is in the P1G2 alloy grouping.
Though A106 GrA exists in the standard, and most Manufacturer of seamless pipe claim to be able to make it, it is quite rare to see this grade stocked in North America, and it would be considered unusual to spec A106 GrA in a piping system.
It is interesting that hydrotesting is not required for this standard, provided that non-destructive testing has been performed, such as ultrasonics or eddy current inspection, and was determined to be capable of full-thickness inspection (i.e., it must have been volumetric NDT). When the hydrotesting option is chosen instead of NDT, the test pressure will be at 60% of the burst pressure of the pipe.
Basic Product Properties:
30 ksi (205 MPa) min. YS
48 ksi (330 MPa) min. UTS
Not Impact Tested
35 ksi (240 MPa) min. YS
60 ksi (415 MPa) min. UTS
Not Impact Tested
40 ksi (275 MPa) min. YS
70 ksi (485 MPa) min. UTS
Not Impact Tested
ASTM A106 seamless pressure pipe (also known as ASME SA106 pipe) is commonly used in the construction of oil and gas refineries, power plants, petrochemical plants, boilers, and ships where the piping must transport fluids and gases that exhibit higher temperatures and pressure levels.
S/A 106 Grade B specs are listed below. If you’re looking for Grade B-specific product offerings
ASTM A106 Seamless Pressure Pipe (also known as ASME SA106 pipe) covers seamless carbon steel nominal wall pipe for high-temperature service. Suitable for bending, flanging and similar forming operations.
NPS 1-1/2″ and under may be either hot finished or cold drawn. NPS 2″ and larger shall be hot finished unless otherwise specified.
Killed steel, with primary melting process being open-hearth, basic-oxygen, or electric-furnace, possibly combined with separate degassing or refining.
Steel cast in ingots or strand cast is permissible.
Hot-finished pipe need not be heat treated.
Cold-drawn pipe shall be heat treated after the final cold draw pass.
|Grade A||Grade B||Grade C|
|Carbon max. %||0.25||0.30||0.35|
|*Manganese %||0.27 to 0.93||*0.29 to 1.06||0.29 to 1.06|
|Phosphorous, max. %||0.035||0.035||0.035|
|Sulfur, max. %||0.035||0.035||0.035|
|Chrome, max. %||0.40||0.40||0.40|
|Copper, max. %||0.40||0.40||0.40|
|Molybdenum, max. %||0.15||0.15||0.15|
|Nickel, max. %||0.40||0.40||0.40|
The minimum wall thickness at any point shall not be more than 12.5% under the nominal wall thickness specified.
Weight of any length shall not vary more than 10% over and 3.5% under that specified. NOTE — NPS 4 and smaller — weighed in lots. Larger sizes shall be weighed separately by length.
Outside Diameter at any point shall not vary from standard specified more than:
|NPS [DN Designator]||Over||Under|
|1/8 to 1-1/2 [6 to 40], incl||1/64 (0.015)||0.4||1/64 (0.015)||0.4|
|Over 1-1/2 to 4 [40 to 100], incl||1/32 (0.031)||0.8||1/32 (0.031)||0.8|
|Over 4 to 8 [100 to 200], incl||1/16 (0.062)||1.6||1/32 (0.031)||0.8|
|Over 8 to 18 [200 to 450], incl||3/32 (0.093)||2.4||1/32 (0.031)||0.8|
|Over 18 to 26 [450 to 650], incl||1/8 (0.125)||3.2||1/32 (0.031)||0.8|
|Over 26 to 34 [650 to 859], incl||5/32 (0.156)||4.0||1/32 (0.031)||0.8|
|Over 34 to 48 [850 to 1200], incl||3/16 (0.187)||4.8||1/32 (0.031)||0.8|
|Grade A||Grade B||Grade C|
|Tensile Strength, min., psi||48,000||60,000||70,000|
|Yield Strength, min., psi||30,000||35,000||40,000|
|NPS||On One Length from Each Lot of|
|Tensile||5 and smaller||400 or less|
|6 and larger||200 or less|
|Bending||2 and smaller||400 or less|
|Flattening||2 through 5||400 or less|
|6 and over||200 or less|
Inspection test pressures produce a stress in the pipe wall equal to 60% of specified minimum yield strength (SMYS) at room temperature. Maximum Pressures are not to exceed 2500 psi for NPS3 and must stay under 2800 psi for the larger sizes. Pressure is maintained for not less than 5 seconds.
Tensile Test — NPS 8 and larger — either transverse or longitudinal acceptable Smaller than NPS 8 — weighed in lots. Larger sizes — by length. Flattening Test — NPS 2-1/2 and larger. Bending Test (Cold) — NPS 2 and under.
|Degree of Bend||Diameter of Mandrel|
|For Normal A106 Uses||90||12 x nom dia. of pipe|
|For Close Coiling||180||8 x nom dia. of pipe|
Lengths required shall be specified on order. No “jointers” permitted unless otherwise specified. If no definite lengths required, following practice applies: Single Random — 17′ ~ 24′ lengths Double Random — 36′ ~ 44′ lengths
(On Tags attached to each Bundle in case of Bundled Pipe) Rolled, Stamped, or Stenciled (Mfrs. Option) Manufacturer’s name or brand. Length of pipe. A106 A, A 106 B, A 106 C. ANSI schedule number. Hydrostatic test pressures and/or NDE; Weight per foot (NPS 4 and larger) or NH if neither is specified. Additional “S” if tested supplementary requirements.
Orders for material under this specification should include the following, as required, to describe the desired material adequately:
|Quantity||Feet, centimeters, or number of lengths|
|Name of material||Seamless|
|Grade||Grade A, Grade B, or Grade C|
|Manufacture||Hot-finished or cold-drawn|
|Size||NPS or Outside Diameter and Schedule Number of Average Wall Thickness|
|Special outside diameter tolerance pipe|
|Inside diameter tolerance pipe, over 10 in ID|
|Length||Specific or random|
|Test Report Required|
*ASTM A 106 grade B Seamless Pressure Pipe
B) Unless otherwise specified by the purchaser, for each reduction of 0.01 % below the specified carbon maximum, an increase of 0.06 % manganese above the specified maximum will be permitted up to a maximum of 1.65 %.
*ASME SA 106 grade B Seamless Pressure Pipe
B) For each reduction of 0.01 % below the specified carbon maximum, an increase of 0.06 % manganese above the specified maximum will be permitted up to a maximum of 1.35 %.
ASTM A106 grade B Seamless Pressure Pipe (ASME SA106) is used in power plants, boilers, petrochemical plants, oil and gas refineries, and ships where the piping must transport fluids and gases that exhibit high pressures and temperatures.
At Reliant Pipes Products, we distribute pipe that meets the latest chemistry standards from ASME.
We stock the full range of ASTM A106 grade B (ASME SA106 grade B):
NPS ¼” to 30” diameter
Schedules 10 through 160, STD, XH and XXH
Schedules 20 through XXH
Wall Thickness beyond XXH, including:- Up to 4” wall in 20” through 24” OD- Up to 3” wall in 10” through 18” OD- Up to 2” wall in 4” through 8” OD
* Special note for Customers: Due to changes in A106 versus SA106, please indicate if you specifically need SA106 on your Purchase order. See changes in allowable chemistry on the S/A106 Spec sheet.
Please note that ASTM International, formerly known as the American Society for Testing and Materials (ASTM), is not in agreement with ASME regarding the specifications for grade B seamless pressure pipe. ASTM A106 grade B pipe and ASME SA 106 grade B pipe now have different specification ranges for acceptable proportions of Manganese.