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STANDARD
SPECIFICATION
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AWWA
C
200-XX ( XX : represents year
of last revision )
" STEEL WATER PIPE - 6``
DIAMETER AND MORE "
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SECTION
1 : GENERAL
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SCOPE
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This standard
covers electrically butt-welded straight-seam
or spiral-seam pipe and seamless pipe
6 in. (150 mm) in nominal diameter
and larger for the transmission and
distribution of water or for use in
other water system facilities.
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INSPECTION
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All work performed
and material furnished under this
standard may be inspected by the purchaser,
but such inspection shall not relieve
the manufacturer of responsibility
to furnish material and perform work
in accordance with this standard.
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QUALITY
ASSURANCE
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The manufacturer
shall maintain a quality-assurance
program to ensure that minimum standards
are met. It shall include a certified
welding inspector (AWS QC1) to verify
that welders and welding procedures
are qualified, procedures are being
followed with limitation of testing,
and quality-assurance functions are
being implemented.
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DEFECTS
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The finished
pipe shall be free from unacceptable
defects. Defects in seamless pipe
or in the parent metal of welded pipe
will be considered unacceptable when
the depth of the defect is greater
than 12.5% of the nominal wall thickness.
The repair of
defects will not be permitted if the
depth of the defect exceeds 1/3 of
the nominal wall thickness of the
pipe and if the length of that portion
of the defect in which the depth exceeds
12.5% is greater than 25% of the outside
diameter of the pipe. Each length
of repaired pipe shall be tested hydrostatically
in accordance with standard requirements.
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MARKING
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A serial number
or other identification shall be painted
in a conspicuous location on each
section of pipe and each special section.
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SECTION
2 : MATERIALS
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ASTM
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If the pipe is
to be manufactured to meet the requirements
of one or more of the ASTM specifications,
the grades of pipe shall be :
- Type E or
S for ASTM A-53
- A-36, A-283,
A-570, A-572 for ASTM A-134
- All grades
for ASTM A-135
- All grades
for ASTM A-139
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FABRICATED
PIPE
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When the pipe
is to be fabricated to meet the standard
requirements; the plates, the sheets,
or the coils shall be selected in
accordance to the following physical
properties and specifications.
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PLATES
- ASTM A-36/36M,
ASTM A-283/A-283M – Grade C et
D
- ASTM A-572/A-572M
– Grade 42,50 and 60
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COILS AND SHEETS
- ASTM A-570/570M – Grade 30 to
50.
For plates, the
maximum allowable thickness variation
shall be 0.010`` under
the ordered thickness.
For the sheets,
the maximum allowable thickness variations
shall be in accordance to the ASTM
A-568 specifications.
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align="CENTER">SECTION
3 : FABRICATION OF PIPE
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GENERAL
REQUIREMENTS
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Pipe produced in a pipe mill shall
be subjected to AWWA C-200 quality-control
procedures. Such pipe shall be manufactured
to meet the standard requirements
of ASTM A-53, A-134, A-135 and A-139.
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FABRICATION
OF PIPE
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The weld shall
be reasonably uniform width and height
for the entire length of the pipe.
By agreement
between the purchaser and the manufacturer,
the welding can be done either by
automatic or manual means.
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All spiral, longitudinal,
and girth seams used in the manufacture
of the pipe shall be full-penetration
welded butt joints.
The maximum radial
offset tolerance on the plates is :
For thickness
of 3/8 in. or less = 0.1875 times
the thickness or 1/16`` - whichever
is larger.
For thickness
of 3/8 in. and over = 0.1875 times
the thickness or 1/8`` - whichever
is smaller.
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WELDING
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The procedures,
the welding operators as well as all
operators shall be qualified under
Sec. IX, part A, of the ASME Boiler
and Pressure Vessel Code, or under
AWS B2.1, or under any other code
mutually agreed on between purchaser
and manufacturer.
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PRODUCTION
WELD TESTS
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The production
weld tests consists of: a two bend-test
(interior and exterior bends), two
reduced-section tension tests and
a macroetch test.
The frequency
of production weld tests : There
shall be at least one set of weld-test
specimens taken of each size, grade,
and wall thickness from work performed
by each production machine and each
operator at a minimum of every 3000
ft. of pipe.
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SECTION
3.4 : HYDROSTATIC TEST
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TEST
PRESSURE
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Each length of
pipe shall be tested by the manufacturer
to a hydrostatic pressure not less
than that determined by the following
formula : P= 2St/D
Where :
P =
minimum hydrostatic test pressure
(psi).
Note :
By agreement between the purchaser
and the manufacturer, when the diameter
and the wall thickness of the pipe
are such that the capacity of the
testing equipment is exceeded by these
requirements, the test pressures may
be reduced or other non destructive
test methods may be used.
S = stress in
pipe wall during hydrostatic test
which shall be 0.75 times the specified
minimum yield point of the steel used,
or as specified by the purchaser.
T = wall thickness
(in.)
D =outside diameter
(in).
The test pressure
shall be held for sufficient time
to observe the weld seams. There shall
be no leaks.
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SECTION
3. 5 : PERMISSABLE VARIATIONS
IN WEIGHT AND DIMENSIONS
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THICKNESS
AND WEIGHT
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Unless specified by the purchaser,
the wall thickness and weight tolerances
for welded pipe shall be governed
by the requirements of the specifications
to which the plates or sheets are
ordered.
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CIRCUMFERENCE
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The pipe shall be substantially round.
The outside circumference of the pipe
shall not vary more than +/- 1%, but
not to exceed ¾`` from
the nominal outside circumference
based on the nominal diameter.
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STRAIGHTNESS
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Finished pipe shall not deviate by
more than 1/8 in. from a 10-ft.
long straightedge held against the
pipe.
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LENGTHS
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Specified pipe lengths on the order
shall be furnished with a tolerance
of +/- 2 ``.
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PREPARATION
OF ENDS
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If pipe is specified to have the ends
bevelled for field butt welding, the
ends shall be beveled to an angle
of 300 with a tolerance
of +50 , -00 with
a width of root face of 1/16``
+/- 1/32``.
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ENDS FITTED WITH FLANGES
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Ends to be fitted with flanges shall
be grinded (longitudinal and spiral
welds), at ground flush for a sufficient
distance to allow proper installation
of the flange.
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OVALITY
(Out-of-Roundness)
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The out-of-roundness of pipe ends shall
be consistent with the diameter and
wall thickness. Any out-of-roundness
shall be limited to a smooth oval
that may be jacked back to a circular
shape.
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DIAMETER
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The tolerance on the diameter of the
ends is of – 1/16`` and
more than 1/8`` of the
specified diameter.
-1/16`` is equal to -0.196``
on the circumference and +1/8``
is equal to +0.393``
on the circumference.
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SQUARENESS
OF ENDS
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For pipe that is to be butt-welded
in the field, the ends of pipe sections
shall not vary by more than 1/8 in.
at any point from a true plane perpendicular
to the axis of the pipe and passing
through the center of the pipe at
the end.
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SPECIAL
ENDS
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By agreement between the manufacturer
and the purchaser, the ends of the
pipe may be supplied with joint configurations
and tolerances other than those described
herein. In such cases, pipe ends shall
conform to the description of detail
drawings provided by the purchaser.
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