| ASTM
A-139 |
SPECIFICATIONS
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STANDARD
SPECIFICATION
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ASTM
A-139-XX (XX=
Represents year of last revision)
ELECTRIC-FUSION
(Arc)- WELDED STEEL PIPE – 4 IN.
DIAMETER AND MORE
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SCOPE
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This specification covers five
grades of electric-fusion (arc)-welded
straight-seam or spiral-seam steel
pipe in 4" to 92" inclusive with
wall thickness up to 1 " inclusive.
Pipe having other dimensions may
be furnished provided such pipe
complies with all other requirements
of this specification and the
grades of steel of the manufactured
pipes. The pipe is intended for
conveying liquid, gas, or vapor.
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STEEL
FABRICATION PROCESS
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The steel shall be made by one
or more of the following processes :
Martin / Bessemer -open hearth
furnace, basic-oxygen or electric-furnace.
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CHEMICAL
COMPOSITION
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The steel shall conform to the
following chemical requirements:
CHEMICAL
COMPOSITION %
Grade
A Grade B Grade
C Grade
D Grade
E
Carbon
..... 0.30
0.30
0.30
0.30
Manganese
1.00
1.00
1.20
1.30
1.40
Phosphorus
.035
.035
.035
.035
.035
Sulfur
.035
.035
.035
.035
.035
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MECHANICAL
PROPERTIES
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Grade
A
Grade B
Grade C
Grade
D
Grade E
Yield strength,
min, ksi (MPa)
30(205) 35(240)
42(290) 46(315)
52(360)
Tensile strength, min, ksi (MPa)
48(330)
60(415)
60(415) 60(415)
66(455)
% min. elongation/ 2" 35
30 25
23
22
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HYDROSTATIC
TEST
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Each length of pipe shall be tested
by the manufacturer to a hydrostatic
pressure that will produce in
the pipe wall a stress of not
less than 60% of the minimum specified
yield point at room temperature.
The pressure shall
be determined by the following
equation :
P=2St/D
P= hydrostatic test pressure, psi
(not to exceed 2800 psi)
1
S= 0.60 to 0.85 times the minimum
yield point of the grade of steel
(lb/sq. in.)
t = specified wall thickness, inches
D= specified outside diameter
1
When the diameter and wall thickness
of pipe are such that the capacity
limits of testing equipment are
exceeded by these requirements,
the test pressures may be reduced
by agreement between the purchaser
and the manufacturer.
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TIME
OF TESTING
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Test pressure shall be held for
not less than 5 sec., or for a
longer time as agreed upon between
the purchaser and the manufacturer.
When agreed upon by the purchaser
and the manufacturer and so stated
on the order, pipe may be tested :
to 1 1/2 times the working pressure
with condition it does not exceed
2800-psi, nor shall the maximum
fiber stress exceed 85% of minimum
yield point of the grade of steel
used.
to a fiber stress which does not
exceed 85% of the minimum yield
point of the grade of steel used
or exceed 2800-psi test pressure.
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PERMISSABLE
VARIATIONS
IN WEIGHTS
AND DIMENSIONS
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Weight
The weight of any length of pipe shall
not vary more than 10% over the specified
weight.
The weight of any length of pipe shall
not vary more than 5% under the specified
weight when the specified wall thickness
is 0.188" or less or more than 5.5%
under when the wall thickness is greater
than 0.188".
Thickness
The minimum wall thickness at any point
shall be not more than 12.5% under
the nominal wall thickness.
Circumference
The pipe shall be substantially round.
The outside circumference of the pipe
shall not vary more than 1.0%, but
not exceeding ¾ in. from the nominal
outside circumference based upon the
diameter specified, except that the
circumference at ends shall be sized,
if necessary, to meet the requirements
of Section 15.
Straightness
Finished pipe shall be commercially
straight. When specific straightness
requirements are desired, the order
should so state and be agreed upon
between the purchaser and the manufacturer.
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LENGTHS
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The tolerance of the specified
lengths is of ± ½².
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FINISH
OF THE
ENDS
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Pipe shall be furnished
with an angle cut of 90°
or beveled ends as specified. All
burrs at the ends of pipe shall be
removed. When pipe ends have to be
beveled for the welding, the ends
shall be beveled on the outside to
an angle of 35°
with a tolerance of ± 2½°
and with a width of root face 1/16"
± 1/32".
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FINISH
OF THE
PIPES
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The repair by manual or automatic arc
welding of defects in the pipe wall
will be permitted, provided their
depth does not exceed 33% the specified
wall thickness.
Defects in the welds, such as sweats
or leaks, shall be repaired or the
piece rejected at the option of the
manufacturer. Repairs of this nature
shall be made by completely removing
the defect, cleaning the cavity, and
then welding. All repaired pipe shall
be subject to hydrostatic testing.
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NUMBER
OF
PRODUCTION
TEST SPECIMENS
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One longitudinal tension test specimen
shall be made from the steel of each
heat, or fraction thereof, used in
the manufacture of the pipe.
One reduced-section production weld
test specimen shall be taken from
a length of pipe from each lot of
3000 ft. of pipe, or fraction thereof,
of each size and wall thickness.
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MARKING
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Each section of pipe shall be marked
with the manufacturer’s distinguishing
marking, the specification number,
the grade of pipe, and other marking
if required and agreed upon between
the purchaser and the manufacturer.
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NOTE: This
is a summary of ASTM specifications.
For additional details and information, please
refer to these specifications.
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SPECIFICATION
ASTM A-139
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MIN MECHANICAL PROPERTIES
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STEEL
GRADE
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Tensile
strength ,min
Ksi ( Mpa )
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Yield strength,min Ksi
( Mpa )
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Elongation
in 2 inches
(50 mm)% min
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A-139
GRADE A
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48
( 330 )
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30
( 205 )
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A-139
GRADE B
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60
( 415 )
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35
( 240 )
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A-139
GRADE C
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60
( 415 )
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42
( 290 )
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A-139
GRADE D
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60
( 415 )
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46
( 315 )
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A-139
GRADE E
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66
( 455 )
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52
( 360 )
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To contact us : info@spiralco.com
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