ASTM A335 Pipe Specifications

ASTM A335 pipe may be either hot finished or cold drawn with the finishing treatment as required in Grade P2 and P12 – The steel shall be made by coarse- grain melting practice. Specific limits, if any, on grain size or deoxidation practice shall be a matter of agreement between the manufacturer and purchaser.

ASTM specification pipe with grades P1, P2, P5, P5b P9, P11, P15, P21, P22, P24, P36, shall be reheated and furnished in the full-annealed, isothermal annealed, or normalized and tempered condition. If furnished in the normalized and tempered condition,the minimum tempering temperature for Grades P5, P5b, P9, P21, and P22 shall be 1250°F [675°C], the minimum tempering temperature for Grades P1, P2, P11, P12, and P15 shall be 1200°F [650°C]. ASTM specification pipe of Grades P1, P2, and P12, either hot finished or cold drawn, may be given a final heat treatment at 1200°F [650°C] to 1300°F [705°C]. ASTM specification pipe with grade P5c, P23, P91, P92, P122, and P911 shall have the following heat treatments; All pipe of Grades P5c shall be given a final heat treatment in the range from 1325°F [715°C] to 1375°F [745°C]. Grades P92 and P911 shall be normalized at 1900°F [1040°C] minimum and tempered at 1350°F [730°C] minimum as a final heat treatment. Grade P122 shall be normalized at 1900°F [1040°C] minimum, and tempered at 1350°F [730°C] minimum as a final heat treatment. Grade P23 shall be normalized at 1900°F [1040°C] minimum with air cooling or accelerated cooling and tempered at 1350°F [730°C] minimum as a final heat treatment. Except when Supplementary Requirement S7 is specified by the purchaser, Grade P91 shall be normalized at 1900°F [1040°C] minimum, and tempered at 1350°F [730°C] mini- mum as a final heat treatment. Alternatively, liquid quenching and tempering is allowed for thicknesses above 3 in. when mutually agreed upon between the manufacturer and the purchaser. In this case the pipe shall be quenched from 1900°F [1040°C] minimum and tempered at 1350°F [730°C] minimum as final heat treatment. Alternative Heat Treatment-Grade P91 Grade P91 shall be normalized in accordance with 5.3 and tempered at a temperature, to be specified by the purchaser, less than 1350°F [730°C]. It shall be purchaser-s responsibility to subsequently temper at 1350°F [730°] minimum. All mechanical tests shall be made on material heat treated. The certification shall reference this supplementary requirement indicating the tempering temperature applied. The notation -S7– shall be included with the required marking of the pipe.

ASTM Specification pipe confirming to ASTM A335 shall have the following chemical properties. Tensile and Hardness Requirements The tensile properties of the ASTM A335 pipe shall conform to the requirements as prescribed. Pipe of Grades P91, P92, and P122 shall have a hardness not exceeding 250 HB/265 HV [25 HRC]. For pipe of Grades P91, P92, P122, and P911, Brinell, Vickers, or Rockwell hardness tests shall be made on a specimen from each lot (see Note 7).

The pipe manufacturer shall explore a sufficient number of visual surface imperfections to provide reasonable assurance that they have been properly evaluated with respect to depth. Exploration of all surface imperfections is not required but may be necessary to ensure compliance with 7.2. Surface imperfections that penetrate more than 121-2 % of the nominal wall thickness or encroach on the minimum wall thickness shall be considered defects. Pipe with such defects shall be given one of the following dispositions: The defect may be removed by grinding provided that the remaining wall thickness is within specified limits.Repaired in accordance with the repair welding provisions.The section of pipe containing the defect may be cut off within the limits of requirements on length. To provide a workman like finish and basis for evaluating conformance with the pipe manufacturer shall remove by grinding the following: Mechanical marks, abrasions and pits, any of which imperfections are deeper than 1-16 in. [1.6 mm]. Visual imperfections, commonly referred to as scabs, seams, laps, tears, or slivers, found by exploration in accordance with 7.1 to be deeper than 5 % of the nominal wall thickness. At the purchaser-s discretion, ASTM A335 pipe shall be subject to rejection if surface imperfections acceptable are not scattered, but appear over a large area in excess of what is considered a workmanlike finish. Disposition of such pipe shall be a matter of agreement between the manufacturer and the purchaser. When imperfections or defects are removed by grinding, a smooth curved surface shall be maintained, and the wall thickness shall not be decreased below that permitted by this specification. The outside diameter at the point of grinding may be reduced by the amount so removed. Wall thickness measurements shall be made with a mechanical calliper or with a properly calibrated non-destructive testing device of appropriate accuracy. In case of dispute, the measurement determined by use of the mechanical calliper shall govern. Weld repair shall be permitted only subject to the approval of the purchaser and in accordance with Specification A 999/A 999M. pipe may be evaluated in accordance with the provisions of Section 7, if the test Signals were produced by visual imperfections such as those listed below:

• Scratches
• Surface roughness
• Dings
• Straightener Marks
• Cutting Chips
• Steel Dies Stamps
• Stop Marks, or
• Pipe Reducer Ripple

Product Analysis At the request of the purchaser, an analysis of two pipe from each lot shall be made by the manufacturer. A lot of ASTM A335 pipe shall consist of the following: NPS Designator Under 2 400 or fraction thereof 2 to 5 200 or fraction thereof 6 and over 100 or fraction thereof

For pipe ordered to NPS or outside diameter, variations in outside diameter shall not exceed those specified. For ASTM A335 pipe ordered to inside diameter, the inside diameter shall not vary more than 6 1 % from the specified inside diameter.

Each length of ASTM A335 pipe shall be subjected to the hydro- static test, except as provided Unless otherwise specified in the purchase order, each length of pipe shall, at the option of the manufacturer, be subjected to the non-destructive electric test as in lieu of the hydrostatic test. When specified by the purchaser, pipe shall be furnished without hydrostatic test and without non-destructive examination. When specified by the purchaser, pipe shall be furnished with both the hydrostatic test and a non-destructive examination having been performed.

When selected by the manufacturer or when specified in the order, as an alternative to the hydrostatic test or when specified in the purchase order in addition to the hydro- static test each pipe shall be examined by a non-destructive examination method in accordance with Practice The following information is for the benefit of the user of this specification: The reference standards defined in 12.8 are convenient standards for standardization of non-destructive examination equipment. The dimensions of these standards should not be construed as the minimum size imperfection detectable by such equipment. Ultrasonic examination can be performed to detect both longitudinally and transversely oriented discontinuities. It should be recognized that different techniques should be employed to detect differently oriented imperfections. The examination may not detect short, deep imperfections. The eddy current examination referenced in this specification has the capability to detect significant discontinuities, especially of the short abrupt type. The flux leakage examination referred to in this specification is capable of detecting the presence and location of significant longitudinally or transversely oriented discontinuities. It should be recognized that different techniques should be employed to detect differently oriented imperfections. The hydrostatic test of Section 11 has the capability to find imperfections of a size that permit the test fluid to leak through the pipe wall so that it may be either visually seen or detected by a loss of fluid pressure. This test may not detect very tight, through-wall imperfections, or imperfections that extend into the wall without complete penetration.

In addition to the information required by Specification A 999/A 999M, the certification shall state whether or not the ASTM A335 pipe was hydrostatically tested. If the pipe was non-destructively examined, the certification shall so state and shall show which practice was followed and what reference discontinuities were used. In addition, the test method information shall be appended to the specification number and grade shown on the certification.

In addition to the marking prescribed in Specification A 999/A 999M, the marking shall include the length, an additional symbol -S-, if the ASTM A335 pipe conforms to any of the Supplementary Requirements S1 to S6, the schedule number, if the pipe is ordered to a schedule number, and the heat number or manufacturer-s number by which the heat can be identified. Furthermore, the marking designated to indicate the test method(s) shall be included. Marking may be by stenciling, stamping, or rolling. Pipe that has been weld repaired in accordance with 7.6 shall be marked -WR.-

A transverse tension test shall be made on a specimen from one end or both ends of each pipe NPS 8 and over. If this supplementary requirement is specified, the number of tests per ASTM A335 pipe shall also be specified. If a specimen from any length fails to meet the required tensile properties (tensile, yield, and elongation), that length shall be rejected subject to retreatment in accordance with Specification A 999/A 999M and satisfactory retest.