The original API specification for 2900 series flanges, integral and weld neck, called for carbon steel 45K minimum yield strength material and a 7,500 psi maximum service pressure. API revised this specification for 2900 series flanges in 1949 to require low alloy steel with 60K minimum yield strength for integral flanges and increased the maximum service pressure to 10,000 psi, but continued the carbon steel 45K minimum yield strength material requirement for weld neck flanges.

The result of this change in maximum service pressure without changing the weld neck flange specifications in any way resulted in over stressed necks on many of these 2900 series weld neck flanges. API has obsoleted all 2900 series flanges, but many remain in use today. Should a need arise for these 2900 series weld neck flanges WOODCO USA will only furnish them in 60K minimum yield strength material and suggests users of such flanges join them to 60K minimum yield strength pipe of the sizes indicated for Flange Weld Neck Dimensions on this web site. Reliable welding of this material requires Qualified Welding Procedures and Qualified Welders. For more about Weld Neck Flanges, Click Here.

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WOODCO USA provides Web Site Tools for identification, estimating, and reference only. Do not use this information for manufacturing or inspection. Users of these tools should not use them as a substitute for professional engineering advice.  Anyone making use of the information presented does so at his own risk and assumes any and all liability resulting from such use.