1、 _ SAE Technical Standards Board Rules provide that: “This report is published by SAE to advance the state of technical and engineering sciences. The use of this report is entirely voluntary, and its applicability and suitability for any particular use, including any patent infringement arising ther
2、efrom, is the sole responsibility of the user.” SAE reviews each technical report at least every five years at which time it may be revised, reaffirmed, stabilized, or cancelled. SAE invites your written comments and suggestions. Copyright 2015 SAE International All rights reserved. No part of this
3、publication may be reproduced, stored in a retrieval system or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without the prior written permission of SAE. TO PLACE A DOCUMENT ORDER: Tel: 877-606-7323 (inside USA and Canada) Tel: +1 724-776-49
4、70 (outside USA) Fax: 724-776-0790 Email: CustomerServicesae.org SAE WEB ADDRESS: http:/www.sae.org SAE values your input. To provide feedback on this Technical Report, please visit http:/www.sae.org/technical/standards/J1792/2_201511 SURFACE VEHICLE STANDARD J1792-2 NOV2015 Issued 1996-09 Revised 2
5、015-11 Superseding J1792-2 APR2007 Self-Propelled Sweepers - Air Flow Performance - Part 2: Suction/Blower Fan Performance RATIONALE The document has been revised to update the referenced documents. 1. SCOPE This SAE Standard establishes a test method and a definition for disclosing the performance
6、of suction/blower fans when applied to self-propelled sweepers that solely use a pneumatic conveyance means for the collection and transfer of “sweepings” into a collection hopper. 1.1 Purpose The purpose of the document describes a test practice for measuring the performance of suction/blower fans
7、used in vacuum and regenerative air street sweepers described in SAE J2130-1. The measured performance considers the air volume movement versus the static depression developed by the fan across a spectrum of different operating conditions. The document also sets-out to propose a format for the prese
8、ntation of the test results. The method in this document can be used to disclose or compare particular operating performance criteria under similar conditions. 2. REFERENCE 2.1 Applicable Documents The following publications form a part of this specification to the extent specified herein. Unless ot
9、herwise indicated, the latest issue of SAE publications shall apply. 2.1.1 SAE Publication Available from SAE International, 400 Commonwealth Drive, Warrendale, PA 15096-0001, Tel: 877-606-7323 (inside USA and Canada) or +1 724-776-4970 (outside USA), www.sae.org. SAE J2130-1 Identification of Self-
10、Propelled Sweepers and Cleaning Equipment Part 1 - Machines with a Gross Vehicle Mass Greater than 5000 kg SAE INTERNATIONAL J1792-2 NOV2015 Page 2 of 7 3. DEFINITIONS 3.1 SWEEPER A self-propelled vacuum or regenerative air street sweeper that is primarily designed to sweep material from highways, p
11、arking lots, airport complexes, industrial and construction sites, and during road maintenance work. The sweeper may use broom means to dislodge and direct material into a pneumatic collection mechanism that is the sole means to convey the swept material into a collection hopper. 3.2 SUCTION/BLOWER
12、FAN Centrifugal fan means for developing the required air movement/pressure employed in the sweepers pneumatic conveyance mechanism. 4. TECHNICAL REQUIREMENTS 4.1 Recommended Apparatus Manometer - Pitot tube - Tachometer - Thermometer - Barometer - Hygrometer (see note in 4.4) - test duct. 4.2 Metho
13、d The machine shall be set up in its optimum running condition according to the recommendations given in its operators instruction manual. The hopper filter meshes shall be clean or may be removed. All air ducts shall be clean and free from debris. Wander hoses, drain off hoses, etc., shall be seale
14、d and blanked-off. The suction pick-up nozzle and flexible conduit shall be removed and substituted with a test duct, a suggested test duct and blanking mechanism is shown in Figures 1 and 2. It is important to monitor the engine and suction/blower fan speed during the test in order that it always r
15、uns at a constant speed. Ideally a digital tachometer connected to the engine or actual fan itself shall be used. An instrument giving a precise speed to the nearest revolution per minute is preferred. The running speed of the fan shall be set to a predetermined level for the test and recorded in th
16、e results. The manometer and pitot tube used in the tests measurements shall be checked to ensure the pitot tube is clean and that the manometer and connecting tubes are perfectly sealed with no leakage to atmosphere. If an electronic manometer is used, first ensure that it is calibrated to zero pre
17、ssure in the inert state. Two small holes shall be provided at 90 degrees to each other in the test duct large enough to permit the insertion of the pitot tube. These holes shall be located mid-way along the test duct to ensure minimum turbulence within the air-stream. Figure 1 - Suggested test duct
18、 SAE INTERNATIONAL J1792-2 NOV2015 Page 3 of 7 Figure 2 - Test duct set-up The ambient temperature shall be recorded before and after the tests in order that results may be corrected to a standard of 20 C (68 F). Barometric pressure shall also be recorded so that corrections may be made to a standar
19、d of 760 mm Hg or 1013 mb (norm at sea level). Corrections for temperature and barometric pressure will ensure that quantifiable comparative data is available to a common standard. The pitot tube shall have a calibrated scale marked with six positions - refer to Figure 3, according to the internal s
20、ize of the test duct being used. The pitot tube is then inserted into the test duct with the probe pointing into the air-stream within 5 degrees of the duct axis. Velocity head pressure readings are then read from the manometer at each of the twelve positions, six for each pass (or hole). Readings t
21、aken are the total velocity head (in millimeters water gauge), shown on the manometer. From these twelve results, the average velocity head and hence air flow velocity and volume shall be calculated based on the ducts cross-sectional area. Prior to and after the test pass, the static pressure within
22、 the eye of the fan shall be recorded. The test process shall be repeated a number of times, each time with the test duct inlet progressively blanked by moving it nearer to the ground to reduce and inhibit air flow into it. Each time the negative pressure within the eye of the fan shall be recorded
23、before and after each test pass. Care must be taken while measuring the velocity head readings to ensure that the pitot tube is held parallel to the walls of the duct. This may be checked by reference to the direction pointer on the tail of the pitot tube (this points in the same direction to the pi
24、tot probe). The static depression shall also be measured within the duct in order to make a correction for air density by connecting the side holes in the pitot tube only to the manometer, leaving the other side open to atmosphere. The total deflection (in millimeters water gauge) shall again then b
25、e read from the manometer. Note that in this application the reading will be a negative pressure and shall be used as such when applying the formulae for correction of duct depression. Figure 3 - Pitot tube positions for a six-point pass in circular ducts SAE INTERNATIONAL J1792-2 NOV2015 Page 4 of
26、7 4.3 Results Tabulation The test results can be typically recorded in the format shown in Figure 4, the corrected values would be derived by the calculation methods given in 4.4. Figure 4 - RESULTS CALCULATION 4.4 Calculations See Equations 1 to 6. (Eq. 1)(Eq. 2)(Eq. 3)(Eq. 4)(Eq. 5) (Eq. 6) Averag
27、e velocity head (in mm H2O 62nu12=Correction for temperature (correct to 20 C)ambient temp. (C) + 273293=Correction for barometric pressure(correct to 1013 mb s e a level)1013barometric pressure (mb)=C orre ctio n for duct depression(correct to std. density)1036310363 + static depression (mm H2O in
28、test duct=Air velocity in duct (m/s)4.032 1 2 3 4 uuuu(multiply by 196.8 to convert m s to ft / min)e=Volume of conveying air (m3s)e(5) duct cross section m2 umultiply by 2118.9 to convert m3sto cfme =SAE INTERNATIONAL J1792-2 NOV2015 Page 5 of 7 NOTE: Corrections may also be made for relative humid
29、ity conditions. Usually the results shall be specified at 50% humidity. High humidity will result in lower air volume recordings due to lower density. The effect is often small and can therefore be ignored. 4.5 Typical Test Summary Format The calculated results for corrected air flow volume versus t
30、he negative air pressure (static pressure) within the fan eye may be shown graphically and presented together with the operational criteria in the format in Figure 5: Figure 5 - Typical test summary format SAE INTERNATIONAL J1792-2 NOV2015 Page 6 of 7 5. NOTES 5.1 Marginal Indicia A change bar (l) l
31、ocated in the left margin is for the convenience of the user in locating areas where technical revisions, not editorial changes, have been made to the previous issue of this document. An (R) symbol to the left of the document title indicates a complete revision of the document, including technical r
32、evisions. Change bars and (R) are not used in original publications, nor in documents that contain editorial changes only. PREPARED BY THE SAE MTC2, SWEEPER, CLEANER, AND MACHINERY COMMITTEE SAE INTERNATIONAL J1792-2 NOV2015 Page 7 of 7 APPENDIX A (INFORMATIVE) (BIBLIOGRAPHY) The following reference
33、s are made to these documents which only serve for information and have merely served as a reference in the preparation of this document. ANSI/AMCA 210-85 American National Standard Laboratory - Methods of testing fans for rating ISO 3966:1977 Measurement of fluid flow in closed conduits - Velocity area method using pitot static tubes ISO 7194:1983 Measurement of fluid flow in closed conduits - Velocity area method of flow measurement in swirling or asymmetric flow conditions in circular ducts by means of current meters or pitot static tubes
