ASTM A53 Standard specification covers Seamless and Welded, Black
and Hot-Dipped Galvanized nominal (average) wall pipe for coiling,
bending, flanging and other special purposes and is suitable for
The steel for both seamless and welded pipe shall be made by one or
more of the following processes: open-hearth, electric furnace, or
basic-oxygen. The weld seam of electric-resistance welded pipe in
Grade B shall be heat treated after welding.
A53 pipe comes in three types and two grades
- A53 Type F, which is longitudinally furnace butt welded or continuous welded
(Grade A only)
- A53 Type E, which is longitudinally electric resistance welded (Grades A and
- A53 Type S, which is seamless pipe, produced by hot working, and possibly
cold finishing, the steel (Grades A and B). ASTM A53, Type S is now
currently an outdated specification and has been replaced by ASTM
A106 specification for seamless carbon steel pipe.
This is a standard set by the standards organization ASTM
International, a voluntary standards development organizations that
sets technical standards for materials, products, systems, and
This specification covers Seamless and Welded, Black and Hot-Dipped
Galvanized nominal (average) wall pipe for coiling, bending,
flanging and other special purposes and is suitable for welding.
Continuous-Welded pipe is not intended for flanging. Purpose for
which pipe is intended should be stated on order. It shall be
permissible to furnish pipe having other dimensions provided that
such pipe complies with all other requirements of this
specification. Supplementary requirements of an optional nature are
provided and shall apply only when specified by the purchaser.
Note 1. The dimensionless designators NPS (nominal pipe size) [DN
(diameter nominal)] have been substituted in this specification for
such traditional terms as ‘nominal diameter,’ ‘size,’ and ‘nominal
Note 2. The term nominal wall thickness has been assigned for the
purpose of convenient designation, existing in name only, and is
used to distinguish it from the actual wall thickness, which may
vary over or under the nominal wall thickness.
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.
Chemical Requirements ASTM A53
|Type S||Type E||Type F|
|Gr. A||Gr.B||Gr. A||Gr. B||Gr. A|
|Carbon max. %||0.25||0.3||0.25||0.3||0.3|
|P, max. %||0.05||0.05||0.05||0.05||0.05|
|Sulfur, max. %||0.045||0.045||0.045||0.045||0.045|
|Nickel, max. %||0.4||0.4||0.4||0.4||0.4|
|Chromium, max. %||0.4||0.4||0.4||0.4||0.4|
|Mo, max. %||0.15||0.15||0.15||0.15||0.15|
|Vanadium, max. %||0.08||0.08||0.08||0.08||0.08|
The total composition for these five elements shall not exceed
|Properties||SMLS & ERW||Con. welded|
|Grade A||Grade B||Grade|
|Tensile Strength, min., psi||48,000||60,000||45,000|
|Yield Strength, min., psi||30,000||35,000||25,000|
- Seamless and Electric-Resistance-Welded — Bending, flattening,
tensile on one length of pipe from each lot of 500 lengths or less
of a size.
- Continuous-Weld — Bending, flattening, tensile
- Con. welded: Continuous-welded
|Couplings — Applied handling tight. Couplings, 2″ and smaller
straight tapped, other sizes taper tapped.|
|Thread Protection — Applied to pipe 4″ and larger.|
|End Finish (unless otherwise specified) –|
|STD or XS, or wall thicknesses less than 0.500 in. (excluding XXS):
Plain and beveled|
|All XXS and wall thicknesses over 0.500 in.: Plain end square cut.|
Hydrostatic inspection test pressures for plain end and threaded
and coupled pipe are specified. Hydrostatic pressure shall be
maintained for not less than 5 seconds for all sizes of seamless
and electric-resistance-weld pipe.
Mechanical tests specified
- Tensile Test — Transverse required on ERW for NPS 8 and large.
- Sending Test (Cold) — STD and XS-NPS 2 and under XXS-NPS 1 1/4 and
|Application||Degree of Bend||Diameter of Mandrel|
|For Normal A53 Uses||90||12 x nom dia. of pipe|
|For Close Coiling||180||8 x nom dia. of pipe|
Flattening Test — NPS 2 and larger STD and XS. (Not required for