APCO VACUUM RELIEF/ AIR INLET VALVES

Transcription

1 BULLETIN 500 JULY 0 APCO VACUUM RELIEF/ AIR INLET VALVES Series 500

2 Vacuum Relief/ Inlet Valves Pipeline Vacuum Prevention And Water Hammer Control APCO Vacuum Relief/ Inlet Valves are proven reliable. They were first introduced over thirty years ago in cooperation with a major midwest consulting engineering firm for their water transmission pipeline project in Sao Paulo, Brazil. Forty (00 mm) size valves were installed without a single failure. Vacuum Relief/ Inlet Valves Pictured below: (300mm) /Vacuum (400mm) Inlet APCO Vacuum Relief/ Inlet Valves were selected because they are ruggedly constructed with a cast iron body and heavy bronze internals, utilizing a precisely coiled and annealed stainless steel spring. Shut-off is drop-tight. Our resilient seating is compression molded (not glued or chemically bonded). A Vacuum Relief/ Inlet Valve is generally shut for prolonged periods and often not readily accessible for inspection. Therefore, it is critically important to the design engineer and client to select a reliable high quality valve. Vacuum Prevention The Vacuum Relief/ Inlet Valve is normally closed. Should the system pressure become negative, the Vacuum Relief/ Inlet Valve will immediately admit air into the system and prevent a vacuum from forming. When system pressure returns to positive, the Vacuum Relief/ Inlet Valve closes air tight. Standard Vacuum Relief/ Inlet Valves are designed to open with a minimal 0.5 psi ( kpa) pressure differential across the orifice. Higher or lower relief settings are available to suit the application. Northern California Water Resources delivers water through Penstock (0, 700mm Dia.) to Southern California Devil s Canyon Power Plant. Where to Install The Vacuum Relief/ Inlet Valve should be installed at high points on a pipeline or a tank or level points on a pipeline where it has been determined a vacuum will occur. This vacuum may: - Cause the pipeline or tank to collapse, or - Cause water column separation to take place resulting in water hammer (pressure surge) when the water column rejoins. Damages Due to Vacuum Conditions Note: Severity of damage due to water column separation and resulting pressure surges in a pipeline when the column rejoins will generally cause greater damage than the initial vacuum condition. However, a vacuum condition can be sufficient to collapse a thin wall pipeline or a sealed water tank. Recommended for water or sewage applications. (Slightly different configuration for sewage applications.) 0 DeZURIK, Inc.

3 Sizing Inlet Valve Release Valve In Flow Mushroom Cap (Optional) 500 TC Closed Open out Small orifice 500 T Threaded Type Release Valve Valve Size and Orifice.5" 5 5 Model A B C 500, 5T 50T 50TC.5" 38 4" 356 5" 7 7" 78 0" 508 in Large orifice " 50 50T 50TC 7" " 4 3" 584 3" 80 Inch Millimeter 503T 503TC 0" " 4 6" 660 Closed Inlet Valve Orifice Seletion Chart Open Pressure Range, psi/kpa " " Release Valve 50 Inch Millimeter 500 TC See outflow capacities on page 5 3

4 Sizing Size Model 3" " A 9 B 79 6" C 5.33" D 33 4" E 0.75" F 9 6" G 5 K 00A.5" 3 L 00A 4.75" 375 5# Class 4" 00 5" 5 6" " C 504C 505C 506C 508C 50C 5C 54C 56C 58C 50C 54C 530C 536C 9" 9.5" 38 7" 78.33" " 9 7.5" 9 4.5" " 394 0" " 343 0" 54.33" " 8.5" 6 5" " 356 0" " 9.5" 4 5.5" " " " " ".75" " " " " " 45 9" " " " " 57 9" 483 4" " " " " 476 " " " " " 59.5" " " " " 74 4" " 40.5" 3.75" " 6.5" 540 0" " " " 508.5" 3 5" " 667.5" 565 4" 600 3" 83 36" 94 3" " 48 0" " " 749 9" " " " " " " 35 36" " " " " 68 57" " 8.375" 60 3" 83.65" " " " 870 Inch Millimeter Adjustable vacuum relief available. Contact factory. APCO compression molded seat seal is guaranteed not to come out for the life of the valve (unique shape of molded seat will not be damaged from extrusion when seated). 500 Flanged Type Closed Open 500 C Flow Large Orifice L Small Orifice Out E = No. of holes F = Dia. of holes G = Dia. of bolt circle See Release Valve Orifice Seletion Chart Closed Open K Pressure Range, psi/kpa " " ".56" 4.9" 6 Release Valve 50 00A 00 Flow Flow 4 Inch Millimeter

5 Combination Vacuum Relief- Inlet and Release Valves Water Hammer Control The large orifice Vacuum Relief/ Inlet Valve combined with a small orifice Release Valve operates for water hammer control as follows: Installed at points where water column separation is anticipated, the large valve will open due to vacuum, admitting air into pipeline which fills the void created by water separation. It will then instantly close, trapping air which will be compressed and act like brakes to slow down the rejoining water column and minimize severe pressure surge (water hammer) as system pressure returns to positive. Performance Graphs Meanwhile, the small orifice Release Valve has also opened due to vacuum and stays open regulating a slow discharge of air from the pipeline to enable a gradual return to normal pipeline system operating pressure without damage. A selection of small orifice Release Valves is available to suit the application. Higher pressure ranges available on application. See outflow capacities below. Inflow curves shown are actual flow capacities at 4.7 psi barometric pressure and at 70 f temperature based on tests conducted by: Phillips Petroleum Company, Engineering Department - Test Division, Edmond Plant, February, 96. Southern Research Institute, Birmingham, Alabama, May 8, 959. Note: Values are given as a guide of what can be expected under specific flow conditions. These values approximate capacities and therefore data shown can be used for general application of the Inlet Valves. Inflow Large Orifice Inlet/ Vacuum Valves Inflow Through Valve in Standard Cubic Feet of Free Per Second (scfs) " / " Valve Size Vacuum Across Valve in psi Outflow Small Orifice Release Valves Orifice Sizes / 3 " / 6 3 / 3 / 8 5 / 3 3 / 6 7 / 3 / 4 5 / 6 3 / 8 7 / 6 / 3 / 4 00 Pressure Differential Across Valve in psi Venting Capacity in Cu. Feet of Free Per Minute 5

6 Specifications Series 500T Vacuum Relief/ Inlet Valve Threaded Type The Vacuum Relief/ Inlet Valve shall consist of a body, cover, baffle, float, seat, stainless steel spring with a galvanized iron hood to prevent debris entering. The seat (orifice) shall be Buna-N fastened to the cover without distortion and have a flow area equal or greater than the valve inlet size to insure full vacuum relief protection during draining, pipeline rupture or water column separation. The orifice shall open, allowing air entry when a vacuum/pressure differential exceeds 0.5 psi ( kpa). The stainless steel float shall be center guided for drop tight shut-off and is normally closed by a stainless steel spring. 500 Vacuum Relief/ Inlet Valve Flanged Type The Vacuum Relief/ Inlet Valve shall have globe type body with integrally cast-on flanged ends. The valve shall have a cross-sectional inflow area 0% greater than equivalent pipe size for full vacuum relief protection during draining, pipeline rupture or water column separation. The Vacuum Relief/ Inlet Valve will be covered by a steel hood to prevent debris entering. The internal valve plug and seat shall be heavy cast bronze. The seat is retained in the body by a heavy cover having a (molded, not glued) resilient Buna-N seal, for positive shut-off. The plug is center guided on both ends to prevent jamming. The plug shall be normally closed, by means of a stainless spring and shall open when a vacuum/pressure differential exceeds 0.5 psi ( kpa). Series 500C Combination Vacuum Relief Inlet and Release Valve Combination Vacuum Relief/ Inlet and Release Valves (double body, double orifice) allow large volume air entry through the large diameter air inlet orifice when a vacuum occurs in a system, then close air tight, trapping the air as the system returns to positive pressure. While the large orifice is closed, the smaller / 6 ", 3 / 3 ", 5 / 3 ", 3 / 6 ", 7 / 3 ", 3 / 8 " or / " (, 3, 4, 5, 6, 0, 3mm) size air release orifice remains open to slowly release trapped air in a controlled manner, to prevent water hammer and excess pressure surges. The 3 / 3 ", 3 / 6 ", 3 / 8 " or / " (3, 5, 0, 3 mm) small orifice Release Valve shall operate (open) up to 50 psi (034 kpa) and / 6 ", 5 / 3 " or 7 / 3 " (, 4, 6 mm) small orifice shall operate (open) up to 300 psi (068 kpa). (Engineer to select small orifice to suit Release control equipment.) The small orifice Release Valve shall operate with a compound lever mechanism of stainless steel, actuated by a stainless steel float. The Inlet Valve, internal plug and seat, shall be heavy cast bronze; the seat retained in the body by a heavy cover; have a (molded, not glued) resilient Buna-N seal for positive shut-off and plug center guided both ends to prevent jamming. The plug shall be normally closed by means of a stainless steel spring and shall open when a vacuum pressure differential exceeds 0.5 psi ( kpa). The Combination Inlet Valve shall be rated 5 lb. or 50 lb. Class. Higher pressure available. 6

7 All 500T, 500TC, 500 and 500C Series valve internals shall be replaceable without removing the valve from the line and the materials of construction certified, conforming to following ASTM specifications: Body & Cover Cast Iron ASTM A6 Gr. B or Ductile Iron ASTM A536 Gr Baffle / ",, " (5, 5, 50 mm) Delrin ASTM D48 Baffle 3" Cast Iron ASTM A48 Cl. 30 Plug & Seat Bronze* ASTM B584 Plug 30" & 36" (750 & 900 mm) Ductile Iron ASTM A Exterior paint Universal Metal Primer FDA approved for potable water Float Stainless Steel ASTM A40 Seat Needle Buna-N Nitrile Rubber Spring Stainless Steel ASTM A76 Hood Galvanized Iron or Steel Commercial Grade Lever Mech. Stainless Steel ASTM A35 T36 *Bronze components meet current lead-free requirements. Valve to be APCO Series 500T Vacuum Relief/ Inlet Valve (threaded type) / " (5 mm) through 3" (80 mm) or Series 500 and Series 500C Combination Inlet/ Release (Flanged Type) 3" (80 mm) through 36" (900 mm). 7

8 Sales and Service For information about our worldwide locations, approvals, certifications and local representative: Web Site: Riverside Ave. N. Sartell, Minnesota Phone: Fax: DeZURIK, 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 only and should not be relied upon unless confirmed in writing by DeZURIK, Inc. Certified drawings are available upon request. Printed in the U.S.A.