ASME B16.9-2018 pdf – Factory-Made Wrought Buttwelding Fittings.
A proof test is successful only when the fitting being tested withstands for at least 180 s a continuous proof test pressure of at least the computed minimum (see para. 9.3.2) without exhibiting loss of containment or evidence of cracking, fissuring, tearing, etc. in the fitting under test.
9.4 AppLicabiLity of Test ResuLts
It is not necessary to conduct an individual test of fittings with all combinations of sizes, wall thicknesses, and materials. A successful proof test on one representative fitting may qualify others to the extent described in paras. 9.4.1, 9.4.2, and 9.4.3.
9.4.1 Size Range. One test fitting may be used to qualify similarly proportioned fittings as defined in para. 9.2.1 with a size range from one-half to twice that for the tested fitting.
9.4.2 Thickness Range. One test fitting may be used to qualify similarly proportioned fittings as defined in para. 9.2.1 with t/D ranges from one-half to three times that for the tested fitting.
9.4.3 MateriaL Grades. The pressure-retaining capacity of a fitting of the same basic design configuration and method of manufacture made from material in a material group as listed in Table 5-1 will be directly proportional to the tensile properties of the materials. Therefore, it is necessary to test only a representative fitting to prove the design of a fitting for all materials in a group.
9.5 Maintenance of ResuLts
The manufacturer shall have a quality control (QC) program that verifies the manufacturing process and material used and ensures that the resulting geometry and design thickness of the fittings or joints manufactured reasonably conform to the geometries tested. The QC program shall control the manufacturing drawings and maintain the QC records showing conformance to these drawings.
Tests made in accordance with and at the time of previous editions of this Standard are not intended to be nullified by the changes made in this edition’s test procedure and requirements, provided the design criteria for the type tested can be determined.
Whenever a significant change is made in the geometry or method of manufacture, the manufacturer shall either retest the new production or show by analysis that the change would not affect the results of prior tests. Examples of changes in geometry that require retests are a change in starting thickness or revised tooling configuration.
9.6 Proof Test Report
A report of the testing for each joint configuration shall be prepared and shall include
(a) description of the test, including the number of tests and f factor used to establish the target proof test
(b) instrumentation and methods of calibration used
(c) material test reports for the assembly’s materials (fitting, pipe, and end caps, if used)
(d) actual final test pressures achieved for each test
(e) length of time at or above the required test pressure (see para. 9.3.4)
(1) calculations performed
(g) location of rupture, if any, including a sketch or photographs of the assembly
(h) pressure design thickness required in critical areas
(1) certification by the manufacturer and by a licensed Authorized Inspector or other third party having experience in pressure component design and testing
Hydrostatic testing of wrought fittings is not required by this Standard. All fittings shall be capable of withstanding, without leakage or impairment of serviceability, a hydrostatic test pressure required by the applicable piping code for seamless pipe of material equivalent to the fitting material, and of the size and wall thickness the fitting marking identifies.
Tolerances for fittings are shown in Table 11-1 and apply to the nominal dimensions given in Tables 6.1-1 through 6.1-11. Where given in the tables, the minimum and maximum dimensions are based on these tolerances. The listings with decimals do not imply precision measurement, such as use of vernier, micrometer, or electronic readout equipment.