APCO SLOW CLOSING AIR/VACUUM VALVES
BULLETIN 613JULY 2011APCO SLOW CLOSINGAIR/VACUUM VALVESSeries 1900
APCO Slow Closing Air/Vacuum ValvesMaximum Air Flow Velocity in Good Pipeline DesignThe Air/Vacuum Valve operates in the normal fashion allowing air to escape freely at any velocity (maximumdischarge velocity is approximately 300 fps (91.44 m/s) at 6.7 psi (46.19 kpa); however, good pipeline designrestricts velocity flows of air to 100 fps (30.48 m/s) which occurs at approximately 1 psi (6.89 kpa).The APCO Slow Closing Air/Vacuum Valve actually consists of a standard Air/Vacuum Valve mounted on topof a Surge Check Unit.The Surge Check Unit operates on the interphase between the kinetic energy in the relative velocity flows ofair and water. The Surge Check is a normally open valve, spring loaded, so that air passes through unrestricted.Then when water rushes into the Surge Check Unit, the disc begins to close against the spring tension andreduces the rate of flow of water into the air valve by means of throttling holes in the disc.This ensures normal gentle closing of the Air/Vacuum Valve regardless of the initial velocity flows involved andminimizes pressure surges when the valve closes.As soon as the Air/Vacuum Valve is closed, the pressure on both sides of the Surge Check Valve disc equalizesand the disc automatically returns to its open position. This means the Air/Vacuum Valve does not needan incipient vacuum to open, but can open at any time the water level drops and line pressure approachesatmospheric and immediately have full re-entry flow of air into the pipeline before a vacuum can form.What It DoesThe APCO Slow Closing Air/Vacuum Valve is designed expressly to eliminate critical shock conditions occurringin those installations where the operating conditions cause a regular air valve to slam open and/or closed.This slow closing feature protects the Air/Vacuum Valve.This type Slow Closing Air/Vacuum Valve should not be considered as relief for shock conditions* whichdevelop elsewhere in the system. However, actual field tests prove the Surge Check Unit may protect theAir/Vacuum Valve in cases where the Air/Vacuum Valve can be destroyed by severe shut-off shock.This protection far outweighs the small cost of the Surge Check Unit when you consider the tremendous fielddamage that can result from an Air/Vacuum Valve failure.* For pipeline shock protection see Bulletin 7000 for details of Hydraulically Controlled Air/Vacuum Valves, or Bulletin 3000 forSurge Relief Valves.Where to Use It1. H igh points in pipelines where the hydraulic gradient and flow conditions are such that a negative pressurecan possibly form.2. High points on sections of pipeline having water velocities in excess of 10 fps (3.048 m/s).3. A djacent to any quick closing valve in a pipeline such as a check or gate valve where a vacuum can beformed upon closure.4. On the discharge of larger deep well turbine pumps between the pump and the check valve.Note to EngineerIf an Air/Vacuum Valve is to be installed inside the pump house, use a threaded or flanged outlet connectionand pipe back into the well or to outside. This will greatly muffle the high noise level caused by the air beingdischarged and provide for drainage of any small amount of water or water vapor that may discharge.Manufactured to AWWA C-512ISO flange connections available2 2011 DeZURIK, Inc.
How To Select Slow Closing Air/Vacuum ValvesStep one: Check pump curve for GPM capacity atno head condition.200AAirReleaseValveSeat DetailAir and VacuumValveAir/VacuumValveGateValve125 lb: 14" (350 mm)250 lb: All SizesStep two: Enter chart with GPM to determine size.Step three: I f valve is to be installed inside pumphouse specify discharge connection.Sizes 4" (100 mm) and 6" (150 mm)available with screwed or flangedconnections. Size 8" (200 mm) andlarger flanged only.*Step four: I f the pump is scheduled to run forprolonged periods (6 - 8 hours) withoutstopping, Automatic Air Release Valvesshould be added.The following method of selection will satisfy normalinstallations. For further information, check with ourengineering department.Air Release ValveandButterfly ValveOptional(See charts on page 4)Surge CheckValveRetainer PlateButterflyValveGuaranteed ASTM qualityMaterials used throughoutPump CapacityGPM/LPMBelow 6300Below 238486301 - 1350023852 - 5110313501 - 3200051107 - 12113332001 - 60000121137 - 22712560001 - 90000227128 - 34068790001 - 140000340691 - 529958140001 - 180000529961 - 681374180001 - 250000681378 - 946353SizeModel(Optional) AirRelease ValveNo.*See Bulletin No. llimeter3
APCO Exclusive FeaturesAPCO Air Release ValveBecause the Air/Vacuum Valve and Surge CheckUnit are each self-contained items, the SurgeCheck Unit can be added to any Air/Vacuum Valvealready in service making it into a Slow ClosingAir/Vacuum Valve.It will open while line is in operation againstpressures up to 300 psi to exhaust small pocketsof entrained air. Stainless steel concave float.(Higher pressure valves available.)APCO Air/Vacuum ValveStainless Steel float and trim, synthetic,non-destructible seat. Positively will not blow shuteven at maximum discharge velocities. Regular125 lb. or 250 lb. flange mates with similar flangeon Surge Check Unit.APCO Surge Check ValveBronze or stainless trim and stainless steel springfor ultimate in protection.Replace Shut-Off Valve With DeZURIKButterfly ValveCosts to excavate pipeline trenches can be greatlyreduced by using DeZURIK Butterfly Valves forisolation instead of gate valves. DeZURIK ButterflyValves are economical, reliable and much shorter,permitting a reduction in depth of the trench.Series 1900Series 1700Series 1300Series 1200Air/Vacuum Valve &Surge Check ValveAir/Vacuum Valve,Surge Check Valve &Air Release ValveAir/Vacuum Valve,Surge Check Valve &Butterfly ValveAir/Vacuum Valve,Surge Check Valve,Air Release Valve &Butterfly ValveSize llimeter1904190619081910191219141916HeightMax.Dia. 125# 732"81325.75" 25.75"65465430.25"30.5"76877534.875" 35.375"88689938.875" 39.5"987100345.125" 45.125"1146114646.875" 46.875"1191119149.25" 49.25"12511251Model WidthHeight125# 1.875"106445.5"115627.5"28"69971131.875" 32.25"81081934.625" 35.5"87990238.875" 39.5"987100345.875" 45.875"1165116545.875" 45.625"1165115949.75" imeterSizes 3" (80mm) & smaller, see Bulletin 586Larger sizes readily available – contact factory.4Simplicity of design – no delicate needle valves tofail or need adjustment. Positively will not blow shut.Model .75"857Height125# odel 5"106445.5"1156Height125# 7646.5"118150.875"129252.25"132755.375"1407
Performance Graph For Air/Vacuum ValveAir inflow/outflow through valve in standard cubic feet of free air per second, (scfs).1234524" 20"18"16"14"12" 10" 8"6"4" 3"2" 1 "21"6Valve SizeVacuum across valve in psiInflowTests Conducted By:Phillips Petroleum CompanyEngineering Department – Test DivisionEdmond Plant Plant Feb. 2, 1961Southern Research Research InstituteBirmingham, Alabama May 8, 1959OutflowPress. diff. across valve in psiCurves shown are actual flow capacities at 14.7 psi barometricpressure at 70 F temperature based on actual test.These figures are not merely flow capacities across the orifice,but flow capacities across the entire valve.In the test set-up air approach velocity is negligible, therefore,actual flow capacity exceeds the values shown on chart.6 2"Valve Size1543210.2 0.3 0.4 0.60.8 123 4 5 6 7 81020 30 40 50100200 300 5001000 2000Surge Pressure ComparisonThe graph shows actual surge pressures experienced closing a standard Air/Vacuum Valve under identicalconditions with and without the APCO Surge Check Unit when filling a 150 psi line. Note that without theSurge Check Unit the maximum surge pressure exceeds line pressure by 550 psi, or approximately fivetimes line pressure, whereas with the Surge Check Unit the maximum surge pressure only exceeded theline pressure by 150 psi, or twice line pressure.On especially critical installations further surge dampening can be effected by using two Surge Check Unitsunder the Air/Vacuum Valve.These pressure recordings were taken on a Minneapolis Honeywell No. 906 visicorder high speed oscillographwith a maximum frequency response of 5000 cps and a linograph travel of 10 inches per sec.01 100Hundredths of a Second2 1003 1004 1005 1006 1007 1008 1009 100 10010 100110 10012750 psi750 psi600 psi600 psi450 psi450 psi300 psi300 psi150 psi150 psi0 psi0 psiWith Surge Check Units 1001 1002Hundredths of a Second 1003 1004 1005 1006 1007 1008 1009 10010 10011 10012Without Surge Check Units5
SpecificationsThe Slow Closing Air/Vacuum Valve shall be four valves furnished assembled and tested as a single unit.The Air/Vacuum Valve must have a stainless steel float guided at each end with stainless stems. The stemsshall be guided through stainless steel bushings inside the body and cover. The seat* must be Buna-N fastenedto the cover with stainless shoulder screws without distortion to allow drop tight closure.The cover shall have a male lip to fit the female body register for positive float guide direction into the seat.Cover outlets may be threaded, flanged, or hooded. (Engineer to specify.)The Surge Check Valve shall be a normally open spring loaded valve consisting of a body, seat and plug boltedto the inlet of the Air/Vacuum Valve. The surge check shall operate on the interphase between the kinetic energyand relative velocity flows of air and water. It will allow air to pass through but water shall actually close the surgecheck, reducing the rate of water flow by means of throttling orifices in the plug to prevent shock closure of theAir/Vacuum Valve. The surge check orifices must be adjustable type to suite operating conditions in the field.The inlet Isolation Butterfly Valve shall be wafer (compact) style constructed to AWWA Standards with handlever and variable position locking device. The seat to be freely interchangeable from the body without the needfor special tools or skill. The seat must be Buna-N, molded with a steel flanged insert for high strength and tightseating. The disc must pivot eccentrically from closed position to clear center valve area.The Air Release Valve shall be side connected to the upper valve, but separated with an Isolation Shut-Off Valve.The internal mechanism shall be the compound lever type to permit the valve to open under pressure to ventpockets of entrapped air as they accumulate. The compound mechanism shall be activated by a stainless steelconcave float to lift the Buna-N needle to shut-off the Air Release orifice.The Slow Closing Air/Vacuum Valve shall have been flow tested in the field, substantiated by test data to showreduction of surge pressure in the valve.Materials shall be certified to ASTM specifications:Air/Vacuum Valve/Air ReleaseCast IronValve Covers, BodiesSurge Check Body andButterfly Valve BodyASTM A126 GR.BFloats & SpringStainless SteelASTM A240Surge Check Seat & DiscBronze*ASTM B584Air Release Valve NeedleBuna-NAir/Vacuum Valve Seat*Buna-N (4"-12", 100-300 mm)14" (350mm) and Larger 250# ClassStainless Steel with Buna-N Molded SealASTM A240ARV Leverage AssemblyDelrinASTM D2133Butterfly Valve ShaftStainless SteelASTM A270Exterior PaintUniversal Metal Primer*Bronze components meet current lead-free requirements.Valve to be APCO Series 1200 Slow Closing Air & Vacuum Valves.Other materials available.6FDA Approved forPotable Water Contact
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Sales and ServiceFor information about our worldwide locations, approvals, certifications and local representative:Web Site: www.dezurik.comE-Mail: info@dezurik.com250 Riverside Ave. N. Sartell, Minnesota 56377 Phone: 320-259-2000 Fax: 320-259-2227DeZURIK, Inc. reserves the right to incorporate our latest design and material changes without notice or obligation.Design features, materials of construction and dimensional data, as described in this bulletin, are provided for your information onlyand should not be relied upon unless confirmed in writing by DeZURIK, Inc. Certified drawings are available upon request.Printed in the U.S.A.
The Air/Vacuum Valve operates in the normal fashion allowing air to escape freely at any velocity (maximum discharge velocity is approximately 300 fps (91.44 m/s) at 6.7 psi (46.19 kpa); however, good pipeline design restricts velocity flows of air
APCO ANS 3.101.1-2007 Unique number identifying the standard APCO ANS 3.101.1-2007 The edition of the standard, which will increase after each revision APCO ANS 3.101.1-2007 The year the standard was approved and published, which may change after each revision. The latest edition of an APCO standard cancels and replaces older versions of
APCO Air/Vacuum Valve, one APCO Air Release Valve and an optional one DeZURIK Butterfly Valve, shipped completely piped and assembled. Price of each Custom Combination Air Valve includes 1" (25 mm) piping and 1" (25 mm) gate or ball valve. Available in 125, 250, 600 and 900 psi (862, 1
Vacuum Relief/Air Inlet Valve will immediately admit air into the system and prevent a vacuum from forming. When system pressure returns to positive, the Vacuum Relief/Air Inlet Valve closes air tight. Standard Vacuum Relief/Air Inlet Valves are designed to open with a minimal 0
NATIONAL INSTITUTE OF TECHNOLOGY: TIRUCHIRAPPALLI-620 015.AIEEE - 20111 Details of Opening and Closing Rank (All India Category and Home State Category 1Tamilnadu) RANK DETAILS (Home State Category) 1 Tamilnadu BRANCH Rank OP OPPH OBC OBCPH SC SCPH ST STPH Details Opening Closing Opening Closing Opening Closing Opening Closing Opening Closing Opening Closing Opening Closing Opening Closing
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In the corner where the #1 suspension line meets the skirt, there is an Apco stamp, along with the individual serial number, canopy type and manufacture date. This data is repeated on a label attached to the bridle in post 1995/6 models. In any correspondence to apco regarding your Mayday, please quote this information. Attachment Procedure
ASTRO APCO-25 is Motorola's APCO-25 compatible Digital Trunking Solution. This implementation uses the standard SmartZoneTM 3600 baud data channel, and the digital voice solu-tion is based on the APCO-25 IMBEvocoder. ASTRO-25 is Motorola's implementation of the Project 25 Digital Trunking standard, which uses the TIA 9600 baud control chan-nel.
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