C&N industrial Group, pipe, fitting and flanges manufacturers,fbe epoxy and pe coating for pipeline since 1991,with brand C&N huitong ,C&N hongcheng.
We have chosen proof testing to qualify our production range of fittings. This is to certify that the fittings manufactured by company C&N the requirements of ASME B16.9 Factory-Made Wrought Buttwelding Fittings Edition 2018.
ASME B16.9 22024 DESIGN PROOF TEST as per latest version.
Required Tests
Proof tests shall be made as set forth in this Standard when the manufacturer chooses proof testing to qualify the fitting design. The proof test shall be based on the computed burst pressure of the fitting and its connecting piping as defined in para. 9.3. A factory-made seg mented elbow (see para. 6.2.4) that has a proof test on a geometrically similar 90-deg elbow need not be tested separately. Lap joint stub ends are exempt from proof testing because they are used in a flange assembly, which will have different ratings depending on service application.
9.2 Test Assembly
- 9.2.1 Representative Components. Fittings that have the same basic design configuration and method of manufacture shall be selected from production for testing and shall be identified as to material, grade, and lot, including heat treatment. They shall be inspected for dimensional compliance to this Standard.
- 9.2.2 Other Components. Straight seamless or welded pipe whose calculated bursting strength is at
least as great as the proof test pressure as calculated in para. - 9.2.3 shall be welded to each end of the fitting to be tested. Pipe sections may have the nominal wall
greater than the thickness indicated by the fitting mark ings. That greater thickness shall not exceed 1.5 times the fitting markings wall. Any internal misalignment greater than 1.5 mm (0.06 in.) shall be reduced by taper boring at a slope not over 1:3.
Any other unequal wall welding preparation shall be in accordance with ASME B16.25. Length of pipe
sections for closures shall be as follows:
(a) Minimum length of pipe shall be one pipe O.D. for NPS 14 (DN 350) and smaller.
(b) Minimum length of pipe shall be one-half pipe O.D. for NPS greater than 14 (DN 350).
9.3 Test Procedure
The test fluid shall be water or other liquid. Hydrostatic pressure shall be applied to the assembly.
At least three specimen tests for each fitting, joint size, or configuration are recommended. The testing factor, f, based on the number of specimen tests performed in the table below is used in the computed test equations. Number of Testing Factor,
| Number of Tests | Testing Factor (f) |
|---|---|
| 1 | 1.10 |
| 2 | 1.05 |
| 3 | 1.00 |
NOTE: Tests of geometrically identical fittings that meet the requirements specified in para. 9.4 may be combined to establish the test factor applied to a set of fittings. The test shall be taken to rupture or held at or above the computed minimum proof pressure for a period of at least 3 min. The test is successful if for each of the tests, the fitting withstands without rupture a proof test pressure at least equal to the computed minimum.
where
D = specified outside diameter of pipe
f = test factor from Table 9.3
P = computed minimum proof test pressure for fitting
S = actual tensile strength of the test fitting, deter mined on a specimen representative of the test
fitting, which shall meet the tensile strength requirements of the applicable material of section 5
t = nominal pipe wall thickness of the pipe that the fitting marking identifies
NOTE: Any dimensionally consistent system of units may be used.
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 representa-tive fitting may represent 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 with a size range from one-half to twice that for the tested fitting. The test of a non reducing fitting qualifies reducing fittings of the same pattern. The test of a reducing fitting qualifies reductions to smaller sizes.
- 9.4.2 Thickness Range. One test fitting may be used to qualify similarly proportioned fittings 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 geometrically identical fitting made of various grades of steel as listed in section 5 will be directly proportional to the tensile properties of the materials, provided the yield-to-tensile ratio as specified in the applicable specification of that material is 0.84 or less. Therefore, it is necessary to test only a single material in a representative fitting to prove the design of the fitting.
9.5 Maintenance of Results
The manufacturer shall have a quality control (QC) program that verifies the manufacturing process used
and ensures that the resulting geometry of the fittings or joints manufactured reasonably conforms 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 test are not intended to be nullified by the changes made in this edition’s test procedure and requirement. Whenever a significant change is made in the geome try 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.
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 calibrations used.
(c) material test reports for the assembly’s materials.
(d) actual final pressures for each test.
(e) length of time from test initiation to the time of burst, or the hold time at or above the computed target pressure.
(f) calculations performed.
(g) location of rupture, if any, including a sketch.
(h) certification by a registered Professional Engineer experienced in pressure component design or a licensed Authorized Inspector.