ASTM A790 Standard Specification

deals ith seamless and straight-seam lded ferritic/austennitic intended for general corrosive service.  Hoever, these are susceptible to embrittlement if used for prolonged period of time at extreme high temperature.

Large Diameter Austenitic Welded Steel Pipe

Large Diameter Austenitic Welded Steel Pipe

ASTM A790 Standard specification covers seamless and straight-seam welded ferritic/austenitic steel pipe for general corrosive service, with particular emphasis on resistance to stress corrosion cracking. The pipe shall be made by the seamless or an automatic welding process, with no addition of filler metal in the welding operation. Heat analysis shall be made to determine the percentages of the elements specified. Tension tests, hardening tests, flattening tests, hydrostatic tests and nondestructive electric tests shall be made to conform to the specified requirements.

This abstract is a brief summary of the referenced standard. It is informational only and not an official part of the standard; the full text of the standard itself must be referred to for its use and application. ASTM does not give any warranty express or implied or make any representation that the contents of this abstract are accurate, complete or up to date.

Significance and Use

This test method may be used for product development and design, production validation, manufacturing process control, lot acceptance, or for a combination thereof.

The rate of inflation in this method does not attempt to mimic that of an actual cushion deployment, nor is it intended to subject the cushion to the dynamic loads, stress, and temperatures during such an event. It is also recognized that the compressed air used for this tests may not leak through the cushion at the same rate as the gas or mixture of gasses typically used in cushion inflators. Rather this method is intended to give a relative indication of the pressure holding ability of the cushion.

The internal volume and internal design of cushions varies greatly. This test method is most useful when comparing data from cushions of the same design and volume. This test method does not provide any data concerning the volume of gas leaking from the bag. At certain higher levels of the initial internal pressure, this test method will irreversibly damage the cushion and change its leakage properties for future testing or for commercial use. The damage to the bag is dependent on the design or shape of a specific bag and the type of coating applied. It is the responsibility of the supplier and / or purchaser to determine if the parameters under which a cushion is tested will be destructive and render the cushion unfit for future use

Within the limits of variance expressed in Section 12, this test method is useful for design and production validation and may be suitable for incorporation in a cushion specification or for lot acceptance testing of commercial shipments.

Scope

1.1 This specification covers seamless and straight-seam welded ferritic/austenitic steel pipe intended for general corrosive service, with particular emphasis on resistance to stress corrosion cracking. These steels are susceptible to embrittlement if used for prolonged periods at elevated temperatures.

1.2 Optional supplementary requirements are provided for pipe when a greater degree of testing is desired. These supplementary requirements call for additional tests to be made and, when desired, one or more of these may be specified in the order.

1.3 Appendix X1 of this specification lists the dimensions of welded and seamless stainless steel pipe as shown in ANSI B36.19. Pipe having other dimensions may be furnished provided such pipe complies with all other requirements of this specification.

1.4 The values stated in either SI units or inch-pound units are to be regarded separately as standard. Within the text, the SI units are shown in brackets. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in non-conformance with the standard. The inch-pound units shall apply unless the M designation of this specification is specified in the order.

Note 1—The dimensionless designator NPS (nominal pipe size) has been substituted in this standard for such traditional terms as nominal diameter, size, and nominal size.

Chemical Composition:

UNS C(max) Mn(max) P(max) S(max) Si(max) Ni Cr Mo N Cu
S31803 0.03 2 0.03 0.02 1 4.5 - 6.5 21.0 - 23.0 2.5 - 3.5 0.08 - 0.20
S32205 0.03 2 0.03 0.02 1 4.5 - 6.5 22.0 - 23.0 3.0 - 3.5 0.14 - 0.20
S31500 0.03 1.2 - 2.00 0.03 0.03 1.40 - 2.00 4.2 - 5.2 18.0 - 19.0 2.50 - 3.00 0.05 - 0.10
S32550 0.04 1.5 0.04 0.03 1 4.5 - 6.5 24.0 - 27.0 2.9 - 3.9 0.10 - 0.25 0.15 - 2.50
S31200 0.03 2 0.045 0.03 1 5.5 - 6.5 24.0 - 26.0 1.2 - 2.00 0.14 - 0.20
S31260 0.03 1 0.03 0.03 0.75 5.5 - 7.5 24.0 - 26.0 2.5 - 3.5 0.10 - 0.30 0.20 - 0.80
S32304 0.03 2.5 0.04 0.04 1 3.0 - 5.5 21.5 - 24.5 0.05 - 0.6 0.05 - 0.20 0.05 - 0.60
S39274 0.03 1 0.03 0.02 0.8 6.0 - 8.0 24.0 - 26.0 2.5 - 3.5 0.24 - 0.32 0.20 - 0.80
S32750 0.03 1.2 0.035 0.02 0.8 6.0 - 8.0 24.0 - 26.0 3.0 - 5.0 0.24 - 0.32 0.5
S32760 0.05 1 0.03 0.01 1 6.0 - 8.0 24.0 - 26.0 3.0 - 4.0 0.20 - 0.30 0.50 - 1.00
S32900 0.08 1 0.04 0.03 0.75 2.5 - 5.0 23.0 - 28.0 1.00 - 2.00
S32950 0.03 2 0.035 0.01 0.6 3.5 - 5.2 26.0 - 29.0 1.00 - 2.50 0.15 - 0.35
S39277 0.025 0.8 0.025 0.002 0.8 6.5 - 8.0 24.0 - 26.0 3.0 - 4.0 0.23 - 0.33 1.2 - 2.00
S32520 0.03 1.5 0.035 0.02 0.8 5.5 - 8.0 24.0 - 26.0 3.0 - 5.0 0.20 - 0.35 0.5 - 3.00
S32906 0.03 0.8-1.5 0.03 0.03 0.05 5.8-7.5 28-30 1.5-2.6 0.3-0.4 0.8
S32003 0.03 2 0.03 0.02 1 3.0 - 4.0 19.5 - 22.5 1.5 - 2.00 0.14 - 0.20

Leave a Reply

Your email address will not be published. Required fields are marked *

You may use these HTML tags and attributes: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <strike> <strong>