Carbon Steel Seamless Pipe
A106 PIPE SPECIFICATIONS
A/SA106
NPS 1/4″- 30″
Schedules 10 through 160, STD, XH and XXH
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.
Koryo steel Products stocks a full range of A106 pipe (SA106 Pipe) in:
- Grades B and C
- 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
A/SA 106 Grade B specs are listed below. If you’re looking for Grade B-specific product offerings, click here.
Scope
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.
Process
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.
Chemical Requirements
| 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 |
| Silicon, min.% | 0.10 | 0.10 | 0.10 |
| 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 |
| Vanadium, max.% | 0.08 | 0.08 | 0.08 |
Total of Cr, Cu, Mo, Ni, and V shall not exceed 1%
Permissible Variations in Wall Thickness
The minimum wall thickness at any point shall not be more than 12.5% under the nominal wall thickness specified.
Permissible Variations in Weights per Foot
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.
Permissible Variations in Outside Diameter
Outside Diameter at any point shall not vary from standard specified more than:
| NPS [DN Designator] | Over | Under | ||
| in. | mm | in. | mm | |
| 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 |
Tensile Requirements
| Seamless | |||
| 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 |
Number of Tests Required
| 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 |
Hydrostatic Testing
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.
Mechanical Tests Specified
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 |
See our full list of pipe testing services.
Lengths
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
Required Markings on Each Length
(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.
Referenced Documents
- ASTM A 530/A 530M Specification for General Requirements for Specialized Carbon and Alloy Steel Pipe
- ASTM E 213 Practice for Ultrasonic Examination of Metal Pipe and Tubing
- ASTM E 309 Practice for Eddy-Current Examination of Steel Tubular Products Using Magnetic Saturation
- ASTM E 381 Method of Macroetch testing Steel Bars, Billets, Blooms, and Forgings
- ASTM E 570 Practice for Flux Leakage Examination of Ferromagnetic Steel Tubular Products
- ASME B36.10M Welded and Seamless Wrought Steel Pipe
General Information
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 | ||||
| Supplementary requirements | |||||
| Test Report Required | |||||
| Specification designation | |||||
| Hydrostatic test | |||||
| Special requirements | |||||
Click here to request a quote for A 106 pipe.
*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 %.
