Stainless Steel Buttweld Fittings

WP347, WP347H, WP321, WP321H, WP317L, WP316, WP316H, WP316L, WP304,304H, WP304L ( ASTM A403 & ASME SA403) - Buttweld Fittings

U.S. Metals is a Premier Worldwide Supplier for All Your Stainless Steel Buttweld Fittings A403 / SA403 Needs.

Our Chrome Alloy Buttweld Fittings inventory is unsurpassed and is considered one of the most extensive chrome inventories in the world!

Turnarounds or outages, planned retrofits or emergency situations, grassroots projects worldwide; U.S. Metals has the experienced staff to assist you on all of your specialty alloy requirements, no matter how detailed the specification, no matter how difficult the situation.

New industry requirements, not an issue. We work closely with agencies like EPRI along with our utility and refining clients to be on the cutting edge of new industry requirements that affect your high energy/high temperature piping systems.

Our inventory is evolving to meet the new specifications that prevent current issues as creep cracking and hardness problems.



  • Trade Name 
    Grade
    UNS #
    Buttweld Fitings
    304
    WP304
    S30400
    A403* / SA403*
    304L
    WP304L
    S30403
    A403* / SA403*
    304H
    WP304H
    S30409
    A403* / SA403*
     
    316
    WP316
    S31600
    A403* / SA403*
    316L
    WP316L
    S31603
    A403* / SA403*
    316H
    WP316H
    S31609
    A403* / SA403*
     
    321
    WP321
    S32100
    A403* / SA403*
    321H
    WP321H
    S32109
    A403* / SA403*
     
    347
    WP347
    S34700
    A403* / SA403*
    347H
    WP347H
    S34709
    A403* / SA403*
     
    317L
    WP317L
    S31703
    A403* / SA403*
    Materials in industry standard designations: 5S, 10S, 40S, 80S per B36.19
    Special customer designated nominal and minimum wall thicknesses can also be furnished.
    Non standard OD & ID are available.
  • This specification covers wrought stainless steel fittings for pressure piping applications.

    Several grades of austenitic stainless steel alloys are included in this specification. Grades are designated with a prefix, based on the applicable ASTM/ASME or MSS standards. For each of the WP stainless grades, several classes of fittings are specified, to indicate whether seamless or welded construction was utilized. Class designations are also utilized to indicate the nondestructive test method and extent of nondestructive examination. A general summary of the fitting classes applicable to all WP grades of stainless steel follows. There are no classes for the CR grades.

    Fitting Classes for WP Grades

    CR Corrosion resistant grade. S through WU Classes do not apply.
    WP-S Seamless
    WP-W Welded, RT or UT all pipe starting material welds made with filler metal. All fitting manufacturer welds except as excluded in A/SA403 paragraph 5.4.3.
    If UT is substituted for RT, all welds must be examined 100% for their length as required by A/SA403 paragraph 5.6
    WP-WX RT all welds with or without filler metal.
    WP-WU UT all welds with or without filler metal.
    WPgrade-grade-class Insert grades (304-304L) and class (S,W,WX, or WU). Applies to fittings meeting all chemical and physical requirements of both grades.
  • Material furnished to A/SA403* shall conform to the requirements of Specification A960/A960M including any supplementary requirements that are indicated in the purchase order. In case of conflict between A/SA403* and Specification A960/A960M, this specification shall prevail.

    Specification A960/A960M identifies the ordering information that should be complied with when purchasing material to this specification.

Information provided in this page is in accordance with the 2013 Edition of the ANNUAL BOOK OF ASTM STANDARDS.
Refer to ASME B & PV Section II for non-identical A/SA requirements