You must comply with this standard if you intend to pressure test gas and liquid petroleum pipelines. You may also need to comply with this standard if you are a registered gas fitter. This standard specifies methods for the pressure testing of petroleum pipelines in accordance with AS Please consult the Contact Officer for more information and to ascertain the level of compliance that may be required. A code of practice is a set of rules which details how people in a certain industry should behave.
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AS Liquid hold-up, pressu Flow pattern, pressure History of the Newark Two-phase frictional p It was published on 4 April To maintain their currency, all Standards are periodically reviewed, and new editions are published. Between editions, amendments may be issued. Standards may also be withdrawn. 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.
Alternatively, both organizations publish an annual printed Catalogue with full details of all current Standards. For more frequent listings or notification of revisions, amendments and withdrawals, Standards Australia and Standards New Zealand offer a number of update options. For information about these services, users should contact their respective national Standards organization. We also welcome suggestions for improvement in our Standards, and especially encourage readers to notify us immediately of any apparent inaccuracies or ambiguities.
Please address your comments to the Chief Executive of either Standards Australia International or Standards New Zealand at the address shown on the back cover. This Standard was issued in draft form for comment as Second edition No part of this work may be reproduced or copied in any form or by any means, electronic or mechanical, including photocopying, without the written permission of the publisher.
The objective of this Standard is to set out methods for the determination of the strength and the leak-tightness of a pipeline test section.
It may also be used for testing other pipelines including pipelines designed to, or operated to, AS Hydrostatic testing of a pipeline is usually carried out by testing a number of isolated test sections. Hydrostatic testing is used to establish— a b the strength and leak tightness of a test section; and the pressure strength of a pipeline for the purposes of determining or confirming the maximum allowable operating pressure of the pipeline.
It may also be applicable to high pressure steel pipelines designed and constructed to national Standards of other countries. 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.
The test may also be used to— a b measure certain mechanical properties of the test section or to relieve or reduce residual stress in the test section; and determine the maximum allowable operating pressure MAOP of a pipeline.
The added volume per unit pressure rise at this end point is double that of the obviously elastic portion of the plot after the effects of residual air are overcome. NOTE: An offset volume of 0. The offset volume excludes the volume of water added to compress residual air. The pressure strength is measured or calculated at the highest point in the test section.
NOTE: For the purposes of this Standard, and particularly for purposes of verification, the transducer includes the sensor, signal conditioning, indicating, and recording apparatus integral to its use. Units shall be converted to SI units before any rounding. For examples of interpretation of specified values in accordance with the rounding method, see AS This Section defines the minimum requirements for accuracy, sensitivity and repeatability of test equipment and the practices to be observed to ensure that readings of test instruments reflect test section parameters and avoid spurious influences.
Indicated readings from verified instruments and equipment shall be used without correction. A sensitivity of 0. Where the test pressure is to be used to determine the MAOP, the accuracy of the pressure-measuring-device shall be 0. Pressure gauges Test grade and industrial grade Bourdon tube pressure gauges shall comply with AS Test grade gauges Deadweight testers Pressure transducers Industrial grade gauges shall be verified against a test grade gauge or deadweight tester or equivalent pressure calibrator.
Records of verification tests shall be maintained. Sensitivity better than 0. Leak test If required, pipe wall temperature measurement devices used for test evaluation shall meet the following requirements see Clause 4. NOTE: Such pipe wall temperature-measuring devices for leak test evaluation are used to determine temperature changes on pipe walls where in ground temperatures may show diurnal changes of approximately 0.
The accuracy requirement is sufficient to determine the temperature-pressure response at the prevailing average pipe temperature. NOTE: An ice-point verification is sufficient. Records of each verification shall be maintained.
Precautions shall be taken to protect the equipment against adverse effects such as weather and other threats. Bourdon tube pressure gauges are particularly susceptible to damage from shock loading in transport and in use, and from impurities in the liquid such as sealing tape. More than one pressuremeasuring device shall be used. Any difference between the indication of the pressuremeasuring devices shall be monitored, and shall be investigated.
Temperature-measuring devices shall be selected to satisfy the requirements of this document. Temperature-measurement points shall be carefully selected to ensure that the measurement is relevant to the relationship being measured. The sensing element and, where necessary, the instrument shall be protected against the effects of ambient and extraneous temperature sources and electrical interference.
NOTE: Pipe temperature measuring points may be located on the surface of the pipe, or the surface of the pipe coating. Where there is any doubt, experimental work should be carried out to determine its suitability. Unstable liquids shall not be used. Liquefied petroleum gas or any other highvapour pressure liquid that is deemed not to be a suitable liquid shall not be used. The test liquid may contain corrosion inhibitors or other appropriate additives. The test liquid shall be selected after consideration of the consequences of a rupture of the test section or escape of the liquid during the test, with regard to the effects such an incident would have on the general public, operating and testing personnel, testing and operating equipment, and the environment.
The method of disposal of the test liquid shall be considered in the selection of the test liquid, and relevant environment protection requirements shall be established. Adequate warning signs shall be displayed along the test section. Except as provided in Clause 2. The test program shall take into account an assessment of stresses in the pipe wall of the test section resulting from mass of the test liquid, end restraints, any additional loading from other structures, and any other significant loadings.
Where a combination of hoop stress, longitudinal stress and radial stress occurs, the cumulative effect of these shall be determined from the maximum shear stress Tresca theory. The test program shall include details of the following: a b The location and identification of the test section.
The elevations of the measuring points and the highest point and lowest point of the test section. The specification and grade of the pipes in the test section, the mill test pressure and the name s of the manufacturer s.
Test pressure ratings of valves, components, connections, and appurtenances in the test section. Ratings may be taken from specifications. NOTE: Consideration is to be given to the effect of pressure on all components in the test section, e. An assessment of the possibility of longitudinal or circumferential expansion due to pressure causing damage to the pipe coating.
Where not water, the type of test liquid to be used and its— i ii density; cubic thermal expansion coefficient; and iii compressibility. The minimum strength test pressure and leak test pressure at the highest and lowest points of the test section, and their relationship to the pressure at the measuring point.
The values in Table 5. The altered values shall be justified and approved. Procedures for cleaning and filling the test section. Procedures for pressurizing the test section. The location of pressurization injection points. Procedures and precautions for the disposal of the test liquid.
Procedures and precautions for the safety of the general public, operating personnel and testing personnel, and operating and testing equipment see also Clause 2. These should include a warning about excess pressure being developed due to solar radiation. The precautions should include the provision of appropriate safety warning signs. The value of combined stresses, as determined in accordance with AS The value of relevant and significant external loads.
The limit of residual air. All valves and equipment that are not suitable shall be isolated or removed. Where necessary, precautions shall be taken to ensure that specified valve seat pressure differentials are not exceeded. Temporary and permanent connections between the test section and all associated test equipment shall be adequately designed and supported.
Where the test liquid in the test section may experience thermal expansion, provision shall be made for the relief of the resulting increase in pressure. Where the test liquid will be subject to temperatures near freezing, precautions shall be taken to protect the equipment and the test section. Tests for which the maximum pressure has the potential to result in yielding of any pipe under test are required to be conducted in a manner that monitors the amount of straining during the test.
Tests that are assessed as not likely to result in yielding of pipe may be conducted to a predetermined pressure end point. This is called a pressure-controlled test. The duration of strength tests is defined to verify the strength of the test section by allowing time for any near critical defects to grow to failure.
The duration of leak tests depends on the method and sensitivity of leak detection methods. Where it is necessary to use more than one pig, a slug of liquid of adequate volume shall separate the pigs, to ensure that air is not entrained in the test liquid behind the last pig. The effects of any surge pressure on the safety of the filling operation shall be taken into account.
006-AS 2885.5 2002