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Stainless Steel pipe specifications STAINLESS STEEL PIPE AND TUBING |
Stainless steels are iron-based alloys usually containing at least 11.5% chromium. Other elements, nickeI being the most Important, may be
added in combination with chromium to obtain special properties.
Stainless steels are highly resistant to corrosive attack and to oxidation at high temperatures. in general, resistance to corrosion and oxidation
increases progressively, though not proportionately, with the increase in chromium content.
Stainless steel pipe and tubing are used for a variety of reasons: to resist corrosion and oxidation, to resist high temperatures, for cleanliness
and low maintenance costs, and to maintain the purity of materials which come In contact with stainless. The inherent characteristics of stainless
steel permits the design of thin wall piping systems without fear of early failure due to corrosion. The use of fusion welding to join such piping
eliminates the need for threading.
Type 304 stainless is the most widely used analysis for general corrosive resistant tubing and pipe applications, it is used in chemical plants,
refineries, paper mills, and food processing industries. Type 304 has a maximum carbon content of .08%. It is not recommended for use in the
temperature range between 800° F and 1650° F due to carbide precipitation at the grain boundaries which can result in inter-granular corrosion
and early failure under certain conditions.
Type 304L. Is the same as 304 except that a .03% maximum carbon content is maintained which precludes carbon precipitation and permits the
use of this analysis in welded assemblies under more severe corrosive conditions. Type 318 is much more resistant to pitting than other
chromium nickel alloys due to the addition of 2% to 3% molybdenum. it is particularly valuable wherever acids, brines, sulphur water, seawater or
halogen salts are encountered. Type 316 is widely used in the sulphite paper industry and for manufacturing chemical plant apparatus,
photographic equipment, and plastics.
Type 316L, like 304L, is held to a maximum carbon content of .03%. This permits its use in welded assemblies without the need of final heat
treatment. It is used extensively for pipe assemblies with welded fitting..
Other fields where stainless steel pipe and tubing are used are: aviation, electronics, automotive, cyrogenic, marine, air conditioning and heating,
medical, architectural and textiles.
Specifications:
ASTM A-312/ASME SA-312 WELDED STAINLESS PIPE
ASTM A-358/ASME SA-358
Scope:
Pipe intended for high temperature and general corrosive service as in A-312, plus electric fusion welded pipe as in A-358 and intended for
high temperature and general corrosive service or both.
General Requirements:
Conforming to the above specifications plus applicable parts us ASTM A-530.
Range:
ASTM A-312 pipe is more commonly found from 1/8" IPS to and including 24” IPS in standard schedules 5, 10, 20, and 40. On special
applications, sizes can be produced to 60” lPS through schedule 80 walls by certain mills. ASTM A-358 is usually produced in sizes 8” IPS
and larger and where filler metal is added to the weld. This specification covers five classes of pipe and are usually determined by the end
application and needs of the pipe.
ASTM A-312 pipe is manufactured by two different processes. Pipe through 6” IPS is manufactured by the continuous welding process and is
very similar to welded tubing.
Coils of flat roll strips are fed into sizing rolls and welded. Material is then annealed (usually in an open air furnace), straightened, cut, pickled,
tested, and inspected.
In full finished pipe, material is cold worked after welding. This can be done by rolling, forging, or drawing the weld bead; but primarily the weld is
rolled.
Pipe 8” IPS and larger is manufactured by the batch method or process. Unlike the continuous welding method. material made by this batch
method is made in single lengths. Plates, cut to length and width, are formed from flat into tubular shape by a press and welded. Material is then
annealed, sized, and straightened, ends trimmed or cut to specific smaller lengths, pickled, and inspected.
Stainless Steel pipe specifications
Pipe and Tubing
“As-Welded” Grade “
“as-welded” pipe and tubing
is straight-seam welded using ASME
qualified automatic gas tungsten-arc
procedures and can be supplied in a wide
range of diameters and wall thicknesses
from any of the weldable corrosion resistant
alloys. Normally furnished with square cut
ends, pipe with beveled, belied, or roilgrooved
ends can be provided. Spot
radiography or 100% radiography of welded
seams can also be performed. Alaskan
pickles and passivates its pipe and tubing to
maintain corrosion resistance and to
prevent surface discoloration from free iron
oxidation. “As-welded” pipe and tubing is
commonly used in pulp and paper mills,
food processing plants. and other industries
where corrosion resistance is essential.
ASTM A 778
This specification covers welded
unannealed stainless steel pipe intended for
low to moderate temperatures and corrosive
service where heat treatment is not required
for corrosion resistance. A 788 is
considered to be the most applicable ASTM
specification for “as welded” pipe and differs
from it only in that a transverse guided-bend
test and a transverse tension test are
required per lot.
ASTM A 213 (ASME SA-213 is
identical)
This specification includes minimum wall
thickness seamless austenitic stainless
steel tubing intended for high temperature
usage such as boiler, superheater and heat
exchanger tubes, Production is generally
limited to tubing ‘A” inside diameter to 5”
outside diameter and .015” to ,500”
inclusive in wail thickness. All material is to
be furnished in the heat treated condition.
Alaskan stocks “average wall” austenitic A
213 tubing.
ASTM A 249 (ASME SA-249 is
generally identical)
This specification covers welded austenitic
stainless steel tubing intended for high
temperature usage such as boiler,
superheater, heat exchanger, or condenser
tubes. Production is generally limited to
tubing 1/8" inside diameter through 5”
outside diameter and .01 5” to .320”
inclusive in wall thickness. All material is to
be furnished in the heat treated condition.
The principal manufacturing procedures
specified under A 249 are:
1. Automatic welding process with no
addition of filler metal.
2. Hydrostatic or non-destructive electric
test of each tube.
3. Tension, flattening, flange. reversebend
and hardness tests required each
lot.
ASTMA 269
This specification covers seamless and
welded austenitic stainless steel tubing
intended for low or high temperature and
general corrosive service. Production is
generally
limited to tubing 1/4” inside diameter and
larger and .020” in nominal wall thickness
and heaver. All material is to be furnished
in the heat treated condition, Mechanical
requirements are the same as listed under
A 249. Alaskan stocks A 269 tubing to
4”OD, with up to 8”OD available,
ASTMA 372 (ASME SA-312 is
generally identical)
This specification covers seamless and
straight-seam welded stainless steel pipe
intended or high temperature and general
corrosive service. The A 312 manufacturing
process is suited to high-volume production
and is therefore generally limited to
diameters and schedule wall thick nesses
shown in ANSI B36.10 and ANSI B36.19
(See page 4,40). Alaskan stocks A 312
pipe with immediate delivery available from
a complete inventory of both common and
special alloys.
The principal manufacturing procedures
specified under A 312 are;
1. Welding without the addition of filler
metal.
2. Annealing after welding.
3. Tension and flattening tests per lot.
4, Hydrostactic testing of each length.
Stainless Steel pipe specifications
Pipe and Tubing (Continued)
ASTM A 358 (ASME SA -358 is austenitic stainless steel pipe intended for procedures specified under A 409 are:
generally identical with some additional high temperature service. Among the 1. Either hydrostatìc. air or gas pressure
requirements) grades covered are five H grades and two testing per lot.
This specification covers stainless steel pipe nitrogen grades that are specifically 2. Transverse guided-bend tests and
intended for high temperature and general intended for high temperature service. All transverse tension tests each length.
corrosive service. Production is generally material is furnished in the heat treated
limited to diameters and schedule wall condition unless waived and specifically MIL-P-1144
thicknesses of 8” and larger as shown in marked ‘HT-O”. Hydrostatic tests are This specification covers seamless and
ANSI B36.10 and ANSI B36.19 (See page required for each length of pipe. Tension welded austenitic stainless steel pipe
4.40). Pipe is normally welded with filler and flattening tests are required per lot. intended for elevated temperature and
metal (except the root pass on Class 4) and general corrosive service, including
can be specified as (a) single or double ASTM A 409 (ASME SA-409 Is cryogenic applications. This specification is
welded; (b) 100%. spot, or no radiography; generally identical with some additional approved for use by the Naval Sea
(c) heat treated after welding. made from requirements) Systems Command and is available for use
annealed plate and not heat treated after This specification covers Schedule 5s and by all Departments and Agencies of the
welding, or made from unannealed plate 10s straight-seam or spiral-seam welded Department of Defense. All pipe is to be
and not heat treated after welding. The stainless steel pipe intended for high furnished in the heat treated condition and
principal manufacturing procedures temperature and general corrosive service. subjected to nondestructive electric or
specified under A 358 are: Production is normally limited to sizes of hydrostatic pressure test as applicable.
1. Hydrostatic testing of each length 14” through 30”, however, special Tension, flattening and intergranular
(unless waived). diameters, lengths and alloys can be corrosion tests are required by lot.
2. Transverse guided-bend tests and specified. Pipe manufactured to A 409 may
transverse tension tests per lot. be heat treated after welding, made from
annealed plate and not heat treated after
ASTM A 376 (ASME SA-376) is welding, or made from unannealed plate
generally identical) and not heat treated after welding.
This specification covers seamless The principal manufacturing