Australian New Zealand Standard AS / NZS Pipelines – Gas and Liquid Petroleum – Field Pressure Testing – Western Australia. AS – , Field Pressure Testing, Revision committed formed, Expected AS – , Safety Management Studies, With. AS/NZS Accessed by CITIC PACIFIC MINING PTY LTD on 03 Dec AS/NZS Australian/New Zealand Standard?.
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The Standard warns that the traditional practice of cutting flattened strap samples from a number of pipes in the section as a means of investigating a premature end-point should be treated with great caution because a number of inaccurate steps are taken in series and the accuracy of the end result is low. The reliability of laboratory tensile tests for assessing premature end-points is further reduced because they are often performed on flattened strap test pieces removed from pipe by oxy-cutting.
T ambient multiplied by the percentage of exposed pipe and combine these ad with the effects of changes in the buried pipe temperature. Hydrostatic with captive caps on a G frame Test pressure There is an additional uncertainty due to a possible 2858.5 between the measured probe tip temperature and the actual pipe and water temperatures.
Dissolution takes place slowly, however, resulting in a slow pressure decline.
This Standard may be applied for pretesting of pipe and components and for testing sections of pipe separate from the field test see Clause 4. Subject to their length, road, rail and river crossings are generally pre-tested to 285.5 appropriate maximum test pressure before being included in a test section that may have different wall thickness or steel properties.
Time-dependent straining takes place for some time, often for several hours in yield tests. The instrument measures precisely both pressure and pressure change.
Some researchers have suggested that a short hold period is preferable to limit the growth of defects. 288.5 indicates that exposed pipe temperatures tend to follow ambient rather than direct exposed sun temperatures due to shading, heat exchange and time lag effects.
The most likely causes are the following: A statement that the test section has been tested and does or does not comply with the requirements of the pipeline specification.
SCOPE OF ACCREDITATION
The accuracy of determination of the pressure strength should not contribute to uncertainty about the MAOP, that is, it should be done with improved accuracy if the result of the division is critical to MAOP.
The requirements are, wherever possible, based on an engineering assessment of what is qs and useful, rather than on what currently available equipment is a most accurate. The values in Column 4 are derived from those in Column 3 by the subtraction of each reading in Column 3 from the highest reading in Column 4. Where the test pressure is to be used to determine the MAOP, the accuracy of the pressure-measuring-device ss be 0.
The precautions should include the provision of appropriate safety warning signs. The number adjacent to each line is the diameter of the equivalent hole.
In the absence of any better information, the radial stress may be taken as zero. It is important that readers assure themselves they are using a current Standard, which should include any amendments which may have been published since the Standard was purchased.
This Standard was prepared to provide a basis on which approving authorities could assess tests or testing programs. Pressure-controlled tests are most commonly used where the stresses produced by the testing pressures are low.
These characterisations tend to show distinct differences in calculated values when changing between ranges. End-points xs this order can be expected in the field pressure test.
At higher pressures, however, the effect may be significant. In the calculation method, this linear equation is drawn and the slope measured. An understanding of the uncertainty of the assessment 28855 whether the test section is leaking or not is an integral element of the assessment of the test.
T is less than? It will continue to dissolve throughout the test and may give rise to a falling pressure readings during the leak test, falsely indicating that a leak is present. History of the Newark Standardized spreadsheet routines could be supplied to testers undertaking such work, requiring insertion of density and pipe aas to derive the variables.
AS Pipelines-Gas and liquid petroleum – Field pressure testing_图文_百度文库
Traceable measurements of ring-expansion yield stress for each pipe based on heat testing. Copies of the verification or calibration records for the — i ii primary pressure measurement instrument; device used for measurement of added volume in volume-strain tests; and iii devices used for measurement of temperature in temperature-correlated leak tests.
Where a test section is wholly or partly submerged, the pressure strength may be considered to be that determined in accordance with this Clause, Where the depth of submergence is subsequently reduced by more than the pressure equivalent of 0.