1、The Authoritative Resource for Safe WaterANSI/AWWA C510-07(Revision of ANSI/AWWA C510-97)AWWA StandardEffective date: Oct. 1, 2008.This first edition approved by AWWA Board of Directors Jan 27, 1969.This edition approved June 24, 2007.Approved by American National Standards Institute July 24, 2008.D
2、ouble Check Valve Backflow Prevention Assembly6666 West Quincy AvenueDenver, CO 80235-3098T 800.926.7337www.awwa.orgAdvocacyCommunicationsConferencesEducation and TrainingScience and TechnologySectionsiiAWWA StandardThis document is an American Water Works Association (AWWA) standard. It is not a sp
3、ecification. AWWA standardsdescribe minimum requirements and do not contain all of the engineering and administrative information normallycontained in specifications. The AWWA standards usually contain options that must be evaluated by the user of thestandard. Until each optional feature is specifie
4、d by the user, the product or service is not fully defined. AWWApublication of a standard does not constitute endorsement of any product or product type, nor does AWWA test, certify,or approve any product. The use of AWWA standards is entirely voluntary. This standard does not supersede or takeprece
5、dence over or displace any applicable law, regulation, or codes of any governmental authority. AWWA standardsare intended to represent a consensus of the water supply industry that the product described will provide satisfactoryservice. When AWWA revises or withdraws this standard, an official notic
6、e of action will be placed on the first page ofthe classified advertising section of Journal AWWA. The action becomes effective on the first day of the month followingthe month of Journal AWWA publication of the official notice.American National StandardAn American National Standard implies a consen
7、sus of those substantially concerned with its scope and provisions. AnAmerican National Standard is intended as a guide to aid the manufacturer, the consumer, and the general public. Theexistence of an American National Standard does not in any respect preclude anyone, whether that person hasapprove
8、d the standard or not, from manufacturing, marketing, purchasing, or using products, processes, or proceduresnot conforming to the standard. American National Standards are subject to periodic review, and users are cautionedto obtain the latest editions. Producers of goods made in conformity with an
9、 American National Standard areencouraged to state on their own responsibility in advertising and promotional materials or on tags or labels that thegoods are produced in conformity with particular American National Standards.CAUTION NOTICE: The American National Standards Institute (ANSI) approval
10、date on the front cover of this standardindicates completion of the ANSI approval process. This American National Standard may be revised or withdrawn atany time. ANSI procedures require that action be taken to reaffirm, revise, or withdraw this standard no later than fiveyears from the date of publ
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13、AssociationPrinted in USAiiiCommittee PersonnelThe AWWA Standards Committee on Backflow Preventers, which reviewed and approvedthis standard, had the following personnel at the time of approval:James T. Cowgill, ChairRichard A. Coates, SecretaryGeneral Interest MembersS.F. Asay, Drinking Water thatm
14、oving parts do not bind or gall; and that there be no distortion that will interferewith the intended performance of the assembly. Flow channels shall be streamlined toprevent cavitation, minimize pressure loss, and eliminate pockets that could entrapforeign materials.4.3.1.1 Access to internal part
15、s. Internal wetted parts shall be accessible forinspection, repair, and renewal without disturbing either the structural integrity ofthe piping system or the integrity of the shutoff valves to isolate the backflowpreventer by the removal of the assembly from the line, using the shutoff valves toisol
16、ate the assembly.4.3.1.2 Connections. End connections, test cocks, and control pipingconnections to components of the backflow prevention assembly shall be eitherthreaded in accordance with ASME B1.20.1, or flanged in accordance with ASMEB16.1, ASME B16.24, or ANSI/AWWA C110/A21.10, or grooved and s
17、houlderedjoints per ANSI/AWWA C606.4.3.1.3 Test cocks. Resilient-seated full-ported test cocks shall be attached tocorrosion-resistant nipples or shall have male threads to be installed in tapped holes. Ateach location on a valve body where such a tapped hole is required, there shall be a bossto per
18、mit sufficient threading for nipples. Test cocks shall have female iron pipe size(IPS) ends on the discharge side. Test connections of 1/8 in. (3 mm) shall be permittedto be either IPS female threads or male in. (6 mm) flared-type connections perSAE J513. The minimum sizes (IPS) of test cocks shall
19、be 1/8 in. (3 mm) forassemblies up to and including 1-in. (25-mm) nominal size; 1/4 in. (6 mm) forassemblies up to and including 2-in. (50-mm) nominal size; 1/2 in. (12 mm) forassemblies 21/2-in. through 4-in. (63-mm through 100-mm) nominal size; and 3/4 in.(19 mm) for assemblies 6 in. (150 mm) and
20、larger. Test cocks shall be installed at thefollowing locations on backflow prevention assemblies:8 AWWA C510-071. On the supply (inlet) side of the supply shutoff valve.NOTE: The #1 test cock is not required for the 1/4-in. and 3/8-in. sizeassemblies.2. Between the supply shutoff valve and the firs
21、t check valve.3. Between the check valves.4. Between the second check valve and the shutoff valve on the outlet side ofthe assembly.4.3.1.4 Valve seats. Provision shall be made for renewal and replacement ofvalve seats.4.3.1.5 Alignment of check valves. Each clapper disk, facing ring, andclamping an
22、d securing bolt or stud shall be concentric to an axis that is normal to theface of the facing ring. When applicable, the unit shall be designed so that the facingring may be clamped and reclamped without warping its face. The clapper must notbe able to tip and catch under the seat ring. When clappe
23、rs or poppets are in awide-open position, they must bear on a definite stop that is so designed and placedthat the action of the water will not twist or bend the valve parts or cause them tochatter. The design shall be such that at any flow rate, from zero to (and including)rated flow, the component
24、 parts shall not create any chatter or noise. Working partsshall be designed and supported in a manner to preclude distortion or misalignment.4.3.1.6 Shutoff valves. Shutoff valves shall be resilient seated. Shutoff valvesshall be considered an integral part of the assembly and shall meet the materi
25、al andhydraulic requirements of this standard. Shutoff valves shall meet the appropriaterecognized standards of AWWA. Shutoff valves on assemblies for fire protectionservice shall meet the appropriate recognized standards of UL and FM.4.3.1.7 Trapped air. Provision shall be made for bleeding trapped
26、 air fromcomponents of the assembly.4.3.2 Operating requirements for double check valve backflow preventionassembly.4.3.2.1 General. The check valves shall be loaded internally so that when thesupply pressure is at least 1 psi (6.89 kPa) and the outlet pressure is atmospheric, eachcheck valve will b
27、e drip-tight in the normal direction of flow. There shall be no leakagepast any check valve when the pressure conditions that cause backflow are present.4.3.2.2 Operation at rated temperature and pressure. Assembly componentsshall operate at, and withstand a thermal test at, the greater of 140F (60C
28、) or at themaximum working water temperature, maximum working water pressure, and theDOUBLE CHECK VALVE BACKFLOW PREVENTION ASSEMBLY 9flow rate as specified in Table 2, for a period of 100 hr without any leakage, damage,permanent deformation, or impairment of operation. During and after the 100 hr a
29、trated temperature and pressure the assembly shall operate satisfactorily per Sec.4.3.2.1.4.3.2.3 Cycle test. The assembly shall withstand operational cycle testingduring which the assembly shall cycle from static to flow to loss of supply pressure fora total of 5,000 cycles as follows: 1,250 cycles
30、 25 percent rated flow 60 psi,1,250 cycles 50 percent rated flow 60 psi, 1,250 cycles 75 percent rated flow 60 psi, 1,250 cycles 100 percent rated flow 60 psi. Note at each cycle, whenthe flow is static, a backpressure shall be applied to the assembly at 150 psi.4.3.3 Installation instructions. The
31、manufacturer shall include with each unitinstallation instructions attached to the unit.4.3.4 Replacement parts. Parts installed during servicing and repair shall beprovided by the original equipment manufacturer (OEM) and be identical to thoseprovided in the assembly when originally approved. In pa
32、rticular, resilient parts suchas valve facing rings, O-rings, and seals fabricated from different materials orcompounds may be identical in appearance but over time may function differentlyfrom the compound originally utilized and approved. Use of non-OEM replacementparts will render the assembly no
33、t in conformance with this standard.Sec. 4.4 Workmanship4.4.1 Foundry and machine work. Foundry and machining work shall beperformed in accordance with the best modern practice for the class of workTable 2 Thermal test minimum flow ratesSize of Assembly Minimum Flow Ratein. (mm) gpm (L/sec)1/4 (6)1(
34、0.63/8 (9)3(19)1/2 (12)7.5 (0.47)3/41 (1925)30 (1.89)11/42 (3150)40 (2.52)21/212 (6430550 (3.15)10 AWWA C510-07involved. Parts shall conform, within allowable tolerances, to the manufacturersrequirements and shall be free from defects.4.4.2 Joints. Flanged joints shall be faced true and machined at
35、right anglesto their respective axes; threaded joints must be concentric and accurately cut.4.4.3 Bronze mounting. Ferrous parts receiving a bronze mounting shall befinished to fit. Such handwork as is required in finishing shall produce a neat,professional, well-fitting, and smoothly operating prod
36、uct.4.4.4 Castings. Castings shall be clean and sound without defects that willweaken their structure or impair their service. Plugging, welding, or repairing ofcosmetic defects is allowed. Repairing of structural defects is not allowed unlessagreed to by the purchaser. Repaired valves shall comply
37、with the testingrequirements of this standard after repairs have been made. Repairs within the boltcircle of any flange face are not allowed.SECTION 5: VERIFICATIONSec. 5.1 Testing and UniformityJoints shall be watertight when subjected to water pressure at twice themaximum working water pressure. A
38、ssembly parts of the same size, model, andmanufacture shall be interchangeable.SECTION 6: DELIVERY*Sec. 6.1 MarkingBackflow prevention assemblies shall be marked distinctly with the size, modeldesignation, and serial number. The markings, which shall not be easily defaced, shallbe either cast or sta
39、mped in the metal or stamped on a brass or stainless-steelnameplate permanently affixed to the assembly. Serial numbers, size, and model shallbe at least 3/16 in. (5 mm) in height. The markings shall include the following:1. Name of manufacturer or trademark.*Governmental marking, packaging, and shi
40、pping references reflect US requirements. Users of ANSI/AWWA C510 outside the United States should verify applicable local and national regulatoryrequirements.DOUBLE CHECK VALVE BACKFLOW PREVENTION ASSEMBLY 112. Type: double check valve or DC.3. Size.4. Model designation.5. Direction of flow (indica
41、ted by an arrow).6. Serial number.7. Maximum working water pressure (MWWP).8. Maximum working water temperature (MWWT) (in degrees Fahrenheitor Celsius).Sec. 6.2 Preparation for ShipmentBackflow prevention assemblies shall be complete when shipped. The manufac-turer shall use due and customary care
42、in preparing the assemblies for shipment sothat no damage as a result of the manufacturers negligence occurs in handling or intransit. The backflow prevention assemblies shall be drained completely and openingsclosed completely before shipment.Sec. 6.3 Affidavit of ComplianceIf required by the purch
43、aser, the supplier shall provide an affidavit certifyingthat the assemblies provided comply with applicable requirements of this standard. Ifrequired by the purchaser, the supplier shall provide a certificate of approval from alaboratory recognized as having expertise in this specialized field.6.3.1
44、 Requirements for approval. Each backflow prevention assemblyapproved by the testing laboratory shall satisfactorily pass a laboratory evaluation andfield evaluation in accordance with the requirements of this section.6.3.1.1 Evaluation in the laboratory. One or more units, selected at randomby the
45、testing laboratory from the manufacturers stock, shall be thoroughly evaluatedby the testing laboratory as to the units design and operating characteristics up to theassemblies rated temperature and pressure. This evaluation shall include a review ofthe working drawings and manufacturers requirement
46、s for parts and materials used,hydrostatic testing, and any other evaluation needed to ensure compliance with thisstandard.6.3.1.2 Evaluation in the field. On completion of a satisfactory laboratoryevaluation, three units of each size and model, selected at random by the testinglaboratory from the m
47、anufacturers stock, shall satisfactorily pass a 12-consecu-tive-month field evaluation under the supervision of the testing laboratory.12 AWWA C510-07Certification by a state health department, a provincial authority, or the regulatoryauthority having jurisdiction with an equivalent field-test progr
48、am shall be acceptableas evidence of satisfactory field-test evaluation.6.3.1.3 Selection of field locations. Field locations shall be selected orapproved by either the testing laboratory or the authority having jurisdiction, orboth.6.3.1.4 Field testing. All three units of each size and model of as
49、semblyundergoing field evaluation shall be examined and tested at least monthly accordingto the operation requirements of this standard. Records of the field examinations andtests shall be kept and any problem and malfunction noted. Any design oroperational problems that prevent the assemblies from meeting the requirements ofthis standard shall be cause for rejection.6.3.1.5 Evaluation report. At the conclusion of the testing program for eachsize and model of assembly, a report shall be compiled by the testing laboratory orauthority, or both, indicating the t
