ASME PTC 8.2
Centrifugal Pumps
Organization: | ASME |
Publication Date: | 1 January 1990 |
Status: | active |
Page Count: | 88 |
scope:
Prepared in accordance with ASME PTC 1 on General Instructions, this Code provides standard directions for conducting; and reporting performance tests of centrifugal pumps, including those of the mixed flow and axial flow types; hereinafter inclusively covered by the term "pumps."
The objective of this Code is to establish rules for conducting tests of pumps to determine, under specified conditions, the following characteristics:
(a) total head produced by the pump;
(b) pump capacity, (rate of flow through the pump);
(c) power input to the pump;
(d} efficiency;
(e) net positive suction head requirements of the pump.
The above characteristics are hereinafter inclusively covered by the term "performance."
In addition to the foregoing, this Code provides nonmandatory appendices which provide additional guidance related to the application of this Code.
This Code applies to the testing of pumps utilizing liquids or mixtures of miscible liquids which have Newtonian viscosity characteristics.
If specific directions in this Code for any particular measurement differ from those given in a reference code for similar measurements, the instructions of this Code shall prevail. It is the intent of this Code that the meaning of all terms be understood and applied as defined in Section 2 of this Code.
This Code mandates testing procedures and acceptable instrumentation for tests designated Type A and Type B. Subsequent reference in this Code will be made to these as Type A and Type B (see Section 3). Prior to the test, the parties to the test must agree in writing to the type of test to be conducted. If this Code is invoked without reference to type, the test shall be conducted in accordance with criteria estabIished for Type A.
Tests may be designated as "single" or "mixed" type tests.
(a) Single-type tests are conducted when procedures and instrumentation from only one type are specified.
(b) The user of this Code may wish to reduce some aspects of the Type A test to Type B. Procedures specified from both types render the test designation as Type B. Upgrading some Type B criteria to Type A is also permissible but again the resultant designation shall be Type B. Any such tests shall be agreed in writing by the parties to the test.
Only tests which comply with, and do not exclude or violate the mandatory requirements of, this Code may be designated as tests conducted in accordance with this Performance Test Code. Characteristics (a) through (d), inclusive, of para. 1.2 shall be determined for both Type A and Type B tests.
Instruments and methods of measurement to satisfy Type A, Type B, or mixed-type tests are given in Section 4 of this Code. Descriptions of instruments and apparatus beyond those specified, but necessary to the conduct of tests under this Code, may be found in the ASME Performance Test Code Supplements on Instruments and Apparatus (PTC 19 Series). If specific directions in this Code for any particular measurement differ from those given in the PTC 19 Series, the instructions in this Code shall prevail.
The tests specified in this Code may be conducted in the manufacturer's shops, on the user's premises or elsewhere as agreed upon, provided such tests meet the requirements of this Code.
Results of tests conducted in accordance with this Code apply solely to the specific pump actually tested. The measured test data refer only to the pump test system. The record of the test and the final test report may include information on the composite unit, including driving and auxiliary equipment.
Tests of model pumps and/or substitute liquids, if in conformance with all mandatory sections of this Code, may be reported as tests conducted in accordance with this Code but, as specified in para. 1.6 of this Code, pertain solely to that liquid and pump. Results extrapolated from tests of model pumps and/or substitute liquids and presented as another pump's performance in meeting guarantees, are outside the scope of this Code. Although the method of extrapolation of the results to predict another pump's performance may be agreed upon by the parties to the test, such extrapolated results shall not be designated results of a test conducted in accordance with this Code [see para. 14(b) and (g) and Appendix E].
Reference by this Code to other codes or standards shall be interpreted to impose the referenced code or standard in effect at the time the agreement to conduct the test is made by the parties to the test.
Test results adjusted for speeds outside the range noted in Table 1.1.1 are outside the Scope of this Code. Tests shall-be conducted at the specified test speed within the criteria established by Table 1.11.
Measurement Uncertainty. By satisfying the instrument accuracy criteria in Table 1.11, and the balance of the procedural requirements of this Code, Types A and B testing will generally provide 95%o or greater confidence that the measurement of the tested parameters identified in Table 1.11 will yield results for which the bounds of the differences between the reported test results and the true values are closely approximated as follows:
Using PTC 19.1, the foregoing values are based on significant typical experience and precision indices for that experience. They are given in this Code as generic values which closely approximate the bounding values for type A and B tests. If specific test values are required for the overall test, PTC 19.1 shall be utilized to determine the specific test uncertainty. This shall be done only by agreement of the parties to the test. Appendix C of this Code provides an example of the use of PTC 19.1 for pump test uncertainty analysis.