|
�uh ' A 53/A 53M — 06a
<br /> manufacturer shall have the option of obtaining the flattening 9.1.1 The weld seam of each length of electric-resistance-
<br /> test specimens required by 7.3.32 or 7.3.3.3, whichever is welded pipe NPS 2 [DN 501 or larger shall be tested with a
<br /> applicable, either prior to or after such hot reducing. nondestructive electric test in accordance with Practices E 213,
<br /> 7.3.4 Continuous-Welded Pipe—A test specimen at least 4 E 273, E 309, or E 570 as follows:
<br /> in. [100 mm] in length shall be flattened cold between parallel 9.1.2 Ultrasonic and Electromagnetic Inspection—Any
<br /> plates in three steps.The weld shall be located at 900 from the equipment utilizing the ultrasonic or electromagnetic principles
<br /> line of direction of force.During the first step, which is a test and capable of continuous and uninterrupted inspection of the
<br /> for ductility of the weld,except as allowed by 7.3.5,7.3.6,and weld seam shall be used.The equipment shall be checked with
<br /> 7.3.7, no cracks or breaks on the inside, outside, or end an applicable reference standard as described in 9.1.3 at least
<br /> surfaces at the weld- shall be present before the distance once every working turn or not more than 8 It to demonstrate
<br /> between the plates is less than three fourths of the specified its effectiveness and the inspection procedures.The equipment
<br /> outside diameter of the pipe. As a second step, the flattening shall be adjusted to produce well-defined indications when the
<br /> shall be continued as a test for ductility away from the weld. reference standard is scanned by the inspection unit in a
<br /> During the second step, except as allowed by 7.3.6 and 7.3.7, manner simulating the inspection of the product.
<br /> no cracks or breaks on the inside,outside,or end surfaces away 9.1.3 Reference Standards—The length of the reference
<br /> from the weld shall be present before the distance between the standards shall be determined by the pipe manufacturer, and
<br /> plates is less than 60%of the specified outside diameter of the they shall have the same specified diameter and thickness as
<br /> pipe. During the third step, which is a test for soundness, the the product being inspected. Reference standards shall contain
<br /> flattening shall be continued until the test specimen breaks or machined notches, one on the inside surface and one on the
<br /> the opposite walls of the test specimen meet. Evidence of outside surface, or a drilled hole, as shown in fig. 1, at the
<br /> laminated or unsound material or of incomplete weld that is option of the pipe manufacturer. The notches shall be parallel
<br /> revealed by the flattening test shall be cause for rejection. to the weld seam,and shall be separated by a distance sufficient
<br /> 7.3.5 Surface imperfections in the test specimen before to produce two separate and distinguishable signals.The t/s-in.
<br /> flattening, but revealed during the first step of the flattening [3.2-mm] hole shall be drilled through the wall and perpen-
<br /> test,shall be judged in accordance with the finish requirements dicular to the surface of the reference standard as shown in Fig.
<br /> in Section 12. 1. Care shall be taken in the preparation of the reference
<br /> 7.3.6 Superficial ruptures as a result of surface imperfec- standard to ensure freedom from fins or other edge roughness,
<br /> tions shall not be cause for rejection. or distortion of the pipe.
<br /> 7.3.7 For pipe with a D-to-t ratio less than 10, because the
<br /> Note 5—The calibration standards shown in Fig. 1 are convenient
<br /> strain imposed due to geometry is unreasonably high on the standards for calibration of nondestructive testing equipment.The dimen-
<br /> inside surface at the 6 and 12 o'clock locations,cracks at such sions of such standards are not to be construed as the minimum sizes of
<br /> locations shall not be cause for rejection. imperfections detectable by such equipment.
<br /> 8. Hydrostatic Test 9.1.4 Acceptance Limits—Table 3 gives the height of accep-
<br /> S.l The hydrostatic test shalt be applied, without leakage tance limit signals in percent of the height of signals produced
<br /> by reference standards. Imperfections in the weld seam that
<br /> through the weld seam or the pipe body. produce a signal greater than the acceptance limit signal given
<br /> 8.2 Plain-end pipe shall be hydrostatically tested to the in Table 3 shall be considered a defect unless the pipe
<br /> applicable pressure given in Table X2.2, and threaded-and- manufacturer can demonstrate that the imperfection does not
<br /> coupled pipe shall be hydrostatically tested to the applicable reduce the effective wall thickness beyond 12.5 % of the
<br /> pressure given in Table X2.3. It shall be permissible, at the specified wall thickness.
<br /> discretion of the manufacturer, to perform the hydrostatic test 9.2 Type S Pipe—As an alternative to the hydrostatic test at
<br /> on pipe with plain ends,with threads only,or with threads and tLe option of the manufacturer or if specified in the purchase
<br /> couplings;and it shall also be permissible to test pipe in either order, the full body of each seamless pipe shall be tested with
<br /> single lengths or multiple lengths. a nondestructive electric test in accordance with Practice
<br /> Noss 4—The hydrostatic test pressures given herein are inspection test E 213, E 309,or E 570.In such cases,each length so furnished
<br /> pnssuras,are notintmded as a basis for design,and do not have tiny direct shall include the mandatory marking of the letters "NDE."
<br /> relationship to working pressures. Except as allowed by 92.6"it is the intent of this nondestruc-
<br /> 83 The minimum hydrostatic test pressure required to tive electric test to reject pipe with imperfections that produce
<br /> satisfy the requirements specified in 8.2 need not exceed 2500 test signals equal to or greater than those produced by the
<br /> psi [17 200 kPa] for pipe NPS 3 [DN 801 or smaller,or 2800 applicable calibration standards.
<br /> psi (19 300 kPa] for pipe larger than NPS 3 (DN 801;however, 9.2.1 If the nondestructive electric test has been performed,
<br /> the manufacturer has the option or using higher test pressures. the lengths shall be marked with the letters "NDE." The
<br /> For all sizes of seamless pipe and electric-resistance-welded certification, if required, shall state Nondestructive Electric
<br /> pipe, the hydrostatic test pressure shall be maintained for at Tested and shall indicate which of the tests was applied.Also,
<br /> least 5 s. the letters NDE shall be appended to the product specification
<br /> number and grade shown on the certification.
<br /> 9. Nondestructive Electric Test 9.2.2 The following information is intended to facilitate the
<br /> 9.1 Type E Pipe: use of this specification:
<br /> 4
<br />
|