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1、STD*UL SUBJECT 448A-ENGL L775 H 7275795 Ob89673 344 December 11, 1995 1 SUBJECT 448A OUTLINE OF INVESTIGATION FOR FLEXIBLE COUPLINGS FOR CONNECTING FIRE PUMPS TO DRIVERS Issue Number 2 DECEMBER I I , 1995 COPYRIGHT o 1995 UNDERWRITERS LABORATORIES INC. Copyright Underwriters Laboratories Inc. Provid
2、ed by IHS under license with ULLicensee=North Carolina State University/5618801100 Not for Resale, 10/21/2006 22:44:38 MDTNo reproduction or networking permitted without license from IHS -,-,- STD-UL SUBJECT 448A-ENGL 1775 E 7275775 Ob87b74 280 2 FLEXIBLE COUPLINGS FOR FIRE PUMPS TO DRIVERS - SUBJEC
3、T 448A DECEMBER 11,1995 No Text on This Page Copyright Underwriters Laboratories Inc. Provided by IHS under license with ULLicensee=North Carolina State University/5618801100 Not for Resale, 10/21/2006 22:44:38 MDTNo reproduction or networking permitted without license from IHS -,-,- DECEMBER 11,199
4、5 FLEXIBLE COUPLINGS FOR FIRE PUMPS TO DRIVERS - SUBJECT 448A 3 CONTENTS FOREWORD INTRODUCTION 1 Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 2 Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5、. . . . . . . . . . . . . . . . . . . . . . . 5 3 Units of Measurement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 4 Undated References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 CONSTRUCTI
6、ON 5 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 6 Sizes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 7 Hubs and Covers . . . . . . . . . . .
7、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 PERFORMANCE 8 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 9 Endurance and Starting Cycle . . . . . . . . . . . . . . . . . . . . . . .
8、. . . . . . . . . . . . . . . . . . . 6 10 Aging Tests, Polymeric Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . , . . . . . . . . 7 MARKING 11 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 12 Instal
9、lation Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Copyright Underwriters Laboratories Inc. Provided by IHS under license with ULLicensee=North Carolina State University/5618801100 Not for Resale, 10/21/2006 22:44:38 MDTNo reproduction o
10、r networking permitted without license from IHS -,-,- STD-UL SUBJECT 44A-ENGL 1795 9275795 UbAb9b U53 m 4 FLEXIBLE COUPLINGS FOR FIRE PUMPS TO DRIVERS - SUBJECT 448A DECEMBER 11,1995 FOREWORD A. This Outline of Investigation contains basic requirements for products covered by Underwriters Laboratori
11、es Inc. (UL) under its Follow-Up Service for this category within the limitations given below and in the Scope section of this Outline of Investigation. They are subject to revision as further experience and investigation may show is necessary or desirable. B. The observance of these requirements by
12、 a manufacturer is one of the conditions of the continued coverage of the manufacturers product. C. A product which complies with the text of this Outline of Investigation will not necessarily be judged to comply with the Outline of Investigation if, when examined and tested, it is found to have oth
13、er features which impair the level of safety contemplated by these requirements. D. A product employing materials or having forms of construction differing from those detailed in the requirements of this Outline of Investigation may be examined and tested according tolhe intent of the requirements a
14、nd, if found to be substantially equivalent, may be judged to comply with the Outline of Investigation. E. UL, in performing its functions in accordance with its objectives, does not assume or undertake to discharge any responsibility of the manufacturer or any other party. The opinions and findings
15、 of UL represent its professional judgment given with due consideration to the necessary limitations of practical operation and state of the art at the time the Outline of Investigation is processed. UL shall not be responsible to anyone for the use of or reliance upon this Outline of Investigation
16、by anyone. UL shall not incur any obligation or liability for damages, including consequential damages, arising out of or in connection with the use, interpretation of, or reliance upon this Outline of Investigation. F. Many tests required by the Outline of Investigations of UL are inherently hazard
17、ous and adequate safeguards for personnel and property shall be employed in conducting such tests. Copyright Underwriters Laboratories Inc. Provided by IHS under license with ULLicensee=North Carolina State University/5618801100 Not for Resale, 10/21/2006 22:44:38 MDTNo reproduction or networking pe
18、rmitted without license from IHS -,-,- - STD-UL SUBJECT Li4AA-ENGL 1775 = 7275775 Ob87b77 T7T DECEMBER II, 1995 FLEXIBLE COUPLINGS FOR FIRE PUMPS TO DRIVERS - SUBJECT 448A 5 INTRODUCTION 1 Scope 1 .I These requirements ,cover flexible couplings intended to connect the shaft of centrifugal fire pumps
19、 to the shaft of centrifugal fire pump drivers. 1.2 Flexible couplings covered by this Outline of Investigation are intended for installation and use in accordance with the Standard for Centrifugal Fire Pumps, NFPA 20-1993. 1.3 A product that contains features, characteristics, components, materials
20、, or systems new or different from those covered by the requirements in this standard, and that involves a risk of fire, electric shock, or injury to persons shall be evaluated using the appropriate additional component and end-product requirements as determined necessary to maintain the acceptable
21、level of safety as originally anticipated by the intent of this standard. A product whose features, characteristics, components, materials, or systems that conflict with specific requirements or provisions of this standard cannot be judged to comply with this standard. Where considered appropriate,
22、revision of requirements shall be proposed and adopted in conformance with the methods employed for development, revision, and implementation of this standard. 2 Components 2.1 Except as indicated in 2.2, a component of a product covered by this standard shall comply with the requirements for that c
23、omponent. 2.2 A component need not comply with a specific requirement that: a) Involves a feature or characteristic not needed in the application of the component in the product covered by the standard; or b) Is superseded by a requirement in the standard. 2.3 A component shall be used in accordance
24、 with its recognized rating established for the intended conditions of use. 2.4 Specific components are recognized as being incomplete in construction features or restricted in performance capabilities. Such components are intended for use only under limited conditions, such as certain temperatures
25、not exceeding specified limits, and shall be used only under specific conditions for which they have been recognized. 3 Units of Measurement 3.1 If a value for measurement is followed by a value in other units in parentheses, the second value may be only approximate. The first stated value is the re
26、quirement. 4 Undated References 4.1 Any undated reference to a code or standard appearing in the requirements of this standard shall be interpreted as referring to the latest edition of that code or standard. Copyright Underwriters Laboratories Inc. Provided by IHS under license with ULLicensee=Nort
27、h Carolina State University/5618801100 Not for Resale, 10/21/2006 22:44:38 MDTNo reproduction or networking permitted without license from IHS -,-,- 6 FLEXIBLE COUPLINGS FOR FIRE PUMPS TO DRIVERS - SUBJECT 448A DECEMBER II, 1995 CONSTRUCTION 5 General 5.1 The flexible coupling shall comply with the
28、applicable portions of the Standard for Centrifugal Fire Pumps, NFPA 20-1993. 6 Sizes 6.1 A flexible coupling shall be constructed to be compatible with the sizes of centrifugal fire pump and driver shafts specified in the installation instructions. 7 Hubs and Covers 7.1 A flexible coupling shall be
29、 constructed in such a manner that the hub or cover component(s) of the driver shaft is mechanically attached to the hub or cover component(s) of the pump shaft. PERFORMANCE 8 General 8.1 Representative samples of flexible couplings are to be subjected to the tests described in Section 9, Endurance
30、and Starting Cycle and Section 1 O, Aging Tests, Polymeric Materials. 9 Endurance and Starting Cycle 9.1 When tested as specified in 9.2 and 9.3, a flexible coupling shall: a) Remain in the installed position; b) Transmit the specified power from the driver; c) Remain completely intact on the shafts
31、; and d) Not show excessive wear such that it becomes inoperable, causes risk of injury to persons, or causes damage to the coupling or shaft which affects the means of attachment that would impair the intended use. Testing with diesel engines in accordance with 9.2 and 9.3 is considered representat
32、ive of electric motor drivers. Copyright Underwriters Laboratories Inc. Provided by IHS under license with ULLicensee=North Carolina State University/5618801100 Not for Resale, 10/21/2006 22:44:38 MDTNo reproduction or networking permitted without license from IHS -,-,- STD-UL SUBJECT VVA-ENGL 1775
33、9275795 ObA9b97 Ab2 M DECEMBER 11, 1995 FLEXIBLE COUPLINGS FOR FIRE PUMPS TO DRIVERS - SUBJECT 448A ,7 9.2 A flexible coupling is to be installed connecting the shafts of a diesel engine and dynometer or other similar torque transmitting device in a manner, as specified in the flexible coupling manu
34、facturers instructions, to represent: a) 200 percent of the maximum permitted angular and parallel misalignment; and b) The maximum gap between the shaft hubs. The flexible coupling is to be operated continuously for 24 hours while transmitting engine horsepower to provide for a shaft torque equival
35、ent to the maximum torque rating of the flexible coupling specified in the coupling manufacturers installation instructions, and the maximum rated speed specified in the coupling manufacturers installation instructions. 9.3 Immediately before and after the endurance test specified in 9.2, the engine
36、 is to be started and accelerated as quickly as possible to rated speed at rated load, operated at that speed for 30 seconds, and then stopped. A total of 40 starting cycles are to be conducted. Twenty cycles are to be conducted before the endurance test, and twenty cycles after the endurance tests.
37、 10 Aging Tests, Polymeric Materials 10.1 After exposure to air-oven aging as specified in 10.2 - 10.4, a polymeric coupling or coupling component that transmits power shall not show signs of cracking and shall comply with the requirements of the Endurance and Starting Cycle Test, Section 9. A flexi
38、ble coupling incorporating a polymeric component need not be subjected to the Endurance and Starting Cycle Test, Section 9, before aging if tested to determine conformance with the requirements after the aging tests. 10.2 The polymeric coupling and coupling part samples to be aged are to be supporte
39、d in a full-draft circulating-air oven that has been preheated at full draft to 212 k1.8OF (100 11.0“C). Samples are not to touch one another or the sides of the oven. The samples of polymeric coupling and coupling parts are to be aged for 180 days at full draft and then allowed to cool in air at 73
40、.4 +_3.6“F (23.0 22.0“C) for at least 24 hours before conducting any tests or dimensional check. As used in this test, the term “full draft“ refers to use of the oven with inlet and outlet vents open and the air vent damper control at a maximum setting to provide 250 to 350 air changes per hour. 10.
41、3 If a polymeric material cannot withstand the temperature specified in 10.2 without excessive softening, distortion, or deterioration, an equivalent air-oven aging test at a lower temperature for a longer period of time may be used. The exposure equivalent to 180 days at 212F (100C) is to be 430 da
42、ys at 188F (87C). 10.4 If polymeric parts are attached to other polymeric or nonpolymeric parts of assemblies, the securement of the parts shall not be impaired after air-oven aging. Copyright Underwriters Laboratories Inc. Provided by IHS under license with ULLicensee=North Carolina State Universit
43、y/5618801100 Not for Resale, 10/21/2006 22:44:38 MDTNo reproduction or networking permitted without license from IHS -,-,- 8 FLEXIBLE COUPLINGS FOR FIRE PUMPS TO DRIVERS - SUBJECT 448A DECEMBER II, 1995 MARKING 11 General 1 I .1 A flexible coupling shall be marked with the following: a) Name or iden
44、tifying symbol of the manufacturer or private labeler; b) Size; c) Distinctive model number, catalog designation, or the equivalent; d) Torque rating; and e) Year of manufacture. Exception: Flexible couplings produced in the last three months of a calendar year may be marked with the following year
45、as the date of manufacture. Couplings produced in the first six months o f a calendar may be marked with the previous year as the date of manufacture. 11.2 Markings required by 11.1 shall be permanent and legible. 11.3 If a manufacturer produces flexible couplings at more than one factory, each indi
46、vidual coupling shall have a distinctive marking to identify it as the product of a particular factory. 12 Installation Instructions 12.1 A copy of the installation and design instructions shall be provided for use as a guide in the examination and testing of flexible couplings. 12.2 The installatio
47、n instructions shall reference the information required for the proper installation of the flexible couplings and shall include at least the following items: a) Model designation; b) information on intended shaft size and dimensional compatibility; c) Torque rating and formula for determining maximu
48、m horsepower; d) Maximum speed in rpm; e) Coupling weight; 9 Coupling dimensions; Copyright Underwriters Laboratories Inc. Provided by IHS under license with ULLicensee=North Carolina State University/5618801100 Not for Resale, 10/21/2006 22:44:38 MDTNo reproduction or networking permitted without license from IHS -,-,- STD-UL SUBJECT LiLiBA-ENGL 1795 W 7275775 Ob87701 240 DECEMBER 11,1995 FLEXIBLE COUPLINGS FOR FIRE PUMPS TO DRIVERS - SUBJECT 448A 9 g) Maximum permitted angular and parallel misalignment;