ASTM A335 P91 High pressure boiler pipes

ASTM A335 P91 Chemical Compositions(%)

Mechanical properties for ASTM A335 P91

Material & Manufacture

Heat Treatment

• A / N+T
• N+T / Q+T
• N+T

Mechanical Tests Specified

• Transverse or Longitudinal Tension Test and Flattening Test, Hardness Test, or Bend Test
• For material heat treated in a batch-type furnace, tests shall be made on 5% of the pipe from each treated lot. For small lots, at least one pipe shall be tested.
• For material heat treated by the continuous process, tests shall be made on a sufficient number of pipe to constitute 5% of the lot, but in no case less than 2 pipe.

Notes for Bend Test:

• For pipe whose diameter exceeds NPS 25 and whose diameter to wall thickness ratio is 7.0 or less shall be subjected to the bend test instead of the flattening test.
• Other pipe whose diameter equals or exceeds NPS 10 may be given the bend test in place of the flattening test subject to the approval of the purchaser.
• The bend test specimens shall be bent at room temperature through 180 without cracking on the outside of the bent portion.