AIR VALVES & CHECK VALVES CATALOGUE
Content Control and Effect of Air in Irrigation Systems 3 Calculating the Number of Valves Required for Installation at Different Points in a System 4 Critical velocity required for transporting air bubbles 5 DG-10 PN 10 6 SG-10 PN 10 8 AV-010 PN 10 10 D-040 PN 16 12 D-040 C 16 S-050 PN 16 17 NR-010 PN 10 19 NR-020 PN 16 21 Installation Guide 24 2
Control and Effect of Air in Irrigation Systems Air in an irrigation system must be controlled because the presence of air bubbles and air pockets, or their absence (vacuum), can cause problems and damage to the system. Problems and Damages Caused by the Presence of Air Pockets and Air Bubbles in Water Pipelines 1. Uneven flow through the pipe sometimes even stopping water flow altogether. 2. High losses of water head and consequently, energy losses. 3. Water hammer (not surge) effects cause damage to the pipes, accessories and connectors. 4. False water meters readings and automatic regulators (and consequent payment for water not supplied, virtual use of water above licensed pumping limits, under utilization of available water supplies, inadequate supply of water to crops because plants receive less water than the volume measured by the hydrometer or water meter). 5. Inadequate supply of water to agricultural crops caused by inhibition of flows and accumulated pressure losses at system ends. 6. Extensive damage to impeller systems in water meters, hydrometers, sprinklers and sprayers. 7. Corrosion damage problems 8. Physical risk - when large volumes of air are released at high velocity, flying parts can cause bodily harm to operators. The problems exacerbated by the presence of a vacuum: 1. Mud and dirt are sucked into the system through drippers. 2. Seals, drippers and other accessories are sucked into the main distribution lines. 3. Uncontrolled entry of chemicals and fertilizers injected into agricultural and landscape irrigation systems. 4. Vacuum induced collapse of pipes and accessories (sub-atmospheric pressures). 5. Increased risk of Surge and Slam conditions during the release of air pockets. 6. Cavitation damage problems. Control of air in irrigation systems using Netafim air valves There are three main types of air valve installed in irrigation systems: Kinetic, Automatic release and combination (double) valves. Kinetic air valves release large quantities of air from non-pressurized pipes and are used mainly when filling a line. Kinetic valves also make it possible to admit large quantities of air when lines are drained and at water column seperation. Kinetic valves are also known as: Air / vacuum valves; large orifice air valves, vacuum breakers, low-pressure air valves and air-relief valves. Automatic air valves continuously release relatively small quantities of air from a pressurized line. The automatic air valve is also known as an: Air release valve; small orifice air valve and as a pressure air valve. Combined air valves fulfill the tasks required of both types of valve kinetic and automatic. In other words they release large volumes of air when filling and admits air while emptying a system and continuously release small volumes air when the line is pressurized. Combination air valves are also known as double orifice air valves. The Advanced Air Valves Range from Netafim flow Control Accessories Technologically, the range is based on A.R.I. s patented rolling seal mechanism, which replaces the old system, which uses the valve float to seal air valve orifices. The rolling seal mechanism and the aerodynamically designed float in the plastic air valves manufactured by A.R.I provide much higher efficiency (much larger orifices) and have greater resilience to withstand dynamic valve closure. The new sealing mechanism enabled the development of small, lightweight air valves with a high cost / benefit ratio. The width of the SG-10 automatic air valve from A.R.I. is a mere 87 millimeters; it stands no more than 140 mm high and weighs just 330 grams. Despite its tiny dimensions, the area of air orifice in this valve reaches 12 mm, which permits the release of 152 cubic meters of air per hour and it can withstand pressures of up to 10 bar. The valves integral self-cleaning mechanism prevents blockages, leaks and particles from sticking to the sealing faces. The DG-10 model valve is just 180 mm wide, (including the protruding drainage funnel) 209 mm tall and weighs only 1.1 kg. With 12mm of automatic orifice area and 804 mm of kinetic orifice area, admission and release of air is very efficient even more efficient than much larger and much heavier air valves, which are overwhelmed and slam closed at lower differential pressures. The R&D team at A.R.I has also developed the AV-010 Guardian kinetic air valve made of composite materials and available in ¾, 1, 2 and 3 sizes to provide solutions for agricultural and landscaping irrigation systems. This product is lightweight, compact and very competitively priced. Most irrigation systems on individual farms have relatively uncomplicated conditions and decisions can be based on the following table: 3
Calculating the Number of Valves Required for Installation at Different Points in a System MODEL SUITABILITY W. PRESSURE DIAMETER AIR VOLUME M3/H The number of 2 DG-10 air valves required during the filling of a line according to line filling rate (with a pressure differential of 0.4 Bar) and pipe diameter. DT-040 Landscaping 10 Bar 1/2, 3/4 24 DG-10 DG-10 AV-010 AV-010 Agriculture + Landscaping Agriculture + Landscaping Agriculture + Landscaping Agriculture + Landscaping 10 Bar 1/2, 3/4, 1 47 10 Bar 2 280 10 Bar 3/4, 1 160 10 Bar 2 350 AV-010 Agriculture 10 Bar 3 900 To calculate the number of DG-10 (Barak) air valves required in an irrigation system, two criteria must be considered: The need to protect against vacuum damage (achieved by admitting air into the system) The need to release air from the system when it is filled with water Air release requirements are usually lower than the air admission requirements for a line, because the rates at which lines can be filled are generally lower. Diagram Number 2 can be used to establish air release requirements during line filling. In Diagram Number 1, it can be seen that one DG-10 valve is enough for pipes with a diameter of up to 8 (and sometimes up to 10 ). This diagram is based on the release of air with a differential pressure of 0.6 bar. Vacuum protection demands are usually higher, and this is particularly true when the line has acute angles of ascent and descent and / or when the pipe has a large diameter. Diagram Number 2 is based on the Hazen Williams friction loss equation; a Hazen Williams coefficient of 110 and a negative pressure differential of 0.4 bar. The number of 2 DG-10 air valves required to protect against vacuum damage during line drainage according to pipe diameter and slops of up to 50% (with a negative pressure differential of 0.4 bar) The number of 2 DG-10 air valves required to protect against vacuum damage during line drainage according to pipe diameter and slops of up to 15% (with a negative pressure differential of 0.4 Bar) 4
Critical velocity required for transporting air bubbles When the rate of water flow drops below the critical speed for air movement, air valves should be located at the critical points. Installation of air valves is particularly important along long horizontal sections of line, because flow rates are too low to carry air pockets and bubbles to the downstream air valves. Installation of air valves is also important on long descending sections of pipe, in which the flow of water must overcome the opposing flow of air (flowing naturally to the high spots). See: Graphs describing critical speeds. CALCULATING THE NUMBER OF EMEK VACUUM PROTECTION AIR VALVES TO BE INSTALLED IN BURIED DRIPPER SYSTEM A vacuum breaker used to prevent vacuum conditions as low as a negative pressure of 1 m must be installed in every buried dripper system to prevent suction of dirt into the drippers and subsequent blockages. A vacuum breaking air valve must also be used to prevent the formation of a vacuum in dripper system laterals and thereby prevent their collapse. If the dripper-irrigated field is relatively flat and has no significant topographical changes, planning of air valve location will be based on the system s working pressures and flow. If the dripper-irrigated field contains substantial topographic changes, calculation of the vacuum breaker numbers and locations will be based on the maximum drainage flow or on the flow of fluids during a burst the size of the pipe diameter, or the larger of the two. AN EXAMPLE OF HOW TO EVALUATE THE SIZE OF VALVES REQUIRED FOR VACUUM PREVENTION IN A DRIPPER SYSTEM WITH A NEGATIVE PRESSURE OF 0.1 BAR. 5
DG-10 PN 10 Combination Air Valve (PATENTED) Description The DG-10 Combination Air Valve has the features of both an Air-release valve and an Air/vacuum valve. The Air-release component of the DG-10 was designed to automatically release to the atmosphere small pockets of air as they accumulate at local high points along a pipeline when the pipeline or piping system is full and operating under pressure. The Air/vacuum component was designed to automatically discharge or admit large volumes of air during the filling or draining of a pipeline or piping system. This valve will open to relieve negative pressures whenever water column separation occurs. Applications Downstreem (after) and upstreem (before) shut-off valve On long water supply lines At peaks alon the line At the end of lines Before water meter On strainers and filters Valve Selection The air valve is available: With 1/2, 3/4", 1", 2" male NPT, BSPT connections, as requested. With a ball valve tap BSPT/NPT male connection upon request. Vacuum check - The valve is available as a valve that will only release air from the system and will not admit air to the system when under pressure condition occur. This feature is accomplished by the addition of a check valve inserted in the air outlet. Main Features Working pressure range: 0.2-10 bar (3-150 psi.) Testing pressure: 16 bar (250 psi.) Working Temperature: 60 C Maximum instantaneous working temperature: 90 C Light, simple and reliable structure. Prevents premature closing: The valve discharges air at high velocity. The orifice of the automatic continuous acting valve is larger than in any other air release valve of it's kind, therefore it discharges air at higher flow rates. The size of the automatic orifice makes its obstruction by debris most unlikely. The valve design - rolling seal mechanism: is less sensitive to pressure differentials than a direct float seal. It accomplishes this by having a comparably large orifice for a wide pressure range (up to 10 bar). The body is made of high strength plastic, and all operating parts are made of specially selected corrosion resistant materials. The float is made for low sealing pressure. Due to its light weight, the valve may be installed on plastic piping systems, as well as other lightweight piping. A threaded drainage outlet enables removal of excess fluids (1 1/2" in the 2", 3/8" in the 3/4", 1") 6
Operation The air & vacuum component, with the large orifice, discharges air at high flow rates during the filling of the system and admits air into the system at high flow rates during its drainage and at water column seperation. High velocity air, should not blow the float shut. Water will life the float and cause sealing of the valve. At any time during system operation, should internal pressure of the system fall below atmospheric pressure, air will re-enter the systems, preventing down-surge and cavitation. The smooth release of air prevents pressure surges and other destructive phenomena. Admitting air in response to negative pressure protects the system from destructive vacuum conditions, prevents damage caused by water column separation. Air re-entry is essential to efficiently drain the system. The automatic small orifice air release component releases entrapped air in the pressurized systems. Pockets of accumulated air may cause the following destructive phenomena: Impediment of effective flow and hydraulic conductivity of the system along with a throttling effect as would a partially closed valve. In extreme cases this will cause complete flow stoppage. Accelerate cavitation damages. High pressure surges. Accelerate corrosion of metal parts. Danger of high-energy burst of compressed air. Inaccuracies in flow metering. As the system starts to fill, the valve functions according to the following stages: 1. Entrapped air is released by the valve 2. Liquid enters the valve, lifting the float which draws the "seal plug" to its sealing position. 3. Entrapped air, which accumulates at peaks along the system (where combination air valves should be installed), rises to the top of the valve, which in turn displaces the liquid in the valve's body. 4. The float descends, peeling the "rolling seal", the smaller orifice opens and the accumulated air is released. 5. Liquid penetrates into the valve and the float rises unrolling the rolling seal to its sealing position. When internal pressure falls below atmospheric pressure (negative pressure): 1. Both orifices will be immediately unplugged and the float drops away. 2. Air is admitted to the system. Dimensions and Weights MODEL DIM. MM WEIGHT KG. ORIFICE AREA MM2 A B C AUTO. KIN. 1, 3/4, 1/2 100 143 3/8 BSP 0.33 7.8 100 2 180 209 11/2 BSP 1.1 12 804 Automatic Air discharge 1/2 parts list and specification NO. PART MATERIAL 3/4 1. Body Reinforced Nylon 2. Drainage Elbow Polypropylene 3. Seal Plug Assembly 3a. Screws Stainless Steel 3b. Plug Cover Reinforced Nylon 3c. Rolling Seal E.P.D.M. 3d. Plug Reinforced Nylon 4. Clamping Stem Reinforced Nylon 5. Float Foamed Polypropylene (Blue) 6. O-Ring BUNA-N 7. Base Reinforced Nylon Optional Ball valve Brass ASTM B124 Air and Vacuume flow rate 1/2 7
SG-10 PN 10 Automatic Air Release Valve segev pate.pend Description Lightweight, small dimensions, simple and reliable structure. The body is made of high strength plastic, and all operating parts are made of specially selected corrosion resistant materials. A.R.I patent, Rolling Seal Mechanism: Dramatically reduces the possibility of obstruction by debris. Discharges high air flow rates upto 160 m 3/h. One size orifice for a wide pressure range (up to 10 bar). Self cleaning mechanism. Working pressure range: 0.2-10 bar (3-150 psi). Available in 1/2" (15mm), 3/4" (20mm), 1" (25mm) BSPT/NPT threaded. Option SG-10-VAC: vacuum check. Available as a valve that will only release air from the system and will not admit air to the system in vacuum condition. Ordering Upon ordering, please specify: model, size, working pressure, threads standard and type of liquid. 8
Dimensions and Weights Air And Vacuum Flow Rate Nominal Size 1/2" (15mm) 100 140 3/4" (20mm) 100 140 1" (25mm) 100 140 Dimensions mm Weight Kg. Orifice Area mm2 A B C Auto Kin. 3/8 BSP 3/8 BSP 3/8 BSP 0.3 5 82 0.3 5 82 0.3 5 82 Parts list and specification No. Part Material 1. Body Reinforced Nylon 2. Drainage Elbow Polypropylene 3. Rolling Seal Rubber E.P.D.M. 4. Claping Stem Reinforced Nylon 5. Float Foamed Polypropylene 6. O-Ring BUNA-N 7. Base Reinforced Nylon 8. Strainer Nylon Optional: Ball Valve Brass ASTM B124 9
AV-010 PN 10 Air and vacuum valve Features Admits air into the pipelines at high flow rates during its drainage. Dynamic design allows high velocity air discharge, up to 0.7 bar differential pressure; Preventing premature closing. Specially suitable for agricultural and landscape irrigation laterals. Drip-tight sealing at low pressure. All parts are UV-protected. Lightweight, small dimensions, simple and reliable structure. The body is made of high strength plastic, and all operating parts are made of specially selected corrosion resistant materials. Working pressure range: 0.2-10 bar (3-150 psi). Available in 3/4 (20mm), 1 (25mm) male threaded, 2 (50mm), 3 (80mm) female threaded NPT/BSPT. Ordering Upon ordering, please specify: model, NPT/BSPT. 10
Dimensions and Weights Air And Vacuum Flow Rate Nominal Size A Dim. mm B Weight Kg. 3/4 (20mm) 60 124 0.1 314 1 (25mm) 60 124 0.1 314 2 (50mm) 73 122 0.2 800 3 (80mm) 104 165 0.6 2000 Orifice Area mm2 Parts list and specification No. Part Material 3/4 Material 2 Material 3 1. Body Polypropylene Reinforced Nylon Reinforced Nylon 2. Cover Polypropylene Polypropylene Reinforced Nylon 3. Disc - Reinforced Nylon Reinforced Nylon 4. Seal BUNA-N E.P.D.M. E.P.D.M. 5. Float Polypropylene Reinforced Nylon Polypropylene 11
D-040 PN 16 Combination Air Valve (PATENTED) Description The D-040 Combination Air Valve has the features of both an Air-release valve and an Air/vacuum valve. The Air-release component of the D-040 was designed to automatically release to the atmosphere small pockets of air as they accumulate at local high points along a pipeline when the pipeline or piping system is full and operating under pressure. The Air/vacuum component was designed to automatically discharge or admit large volumes of air during the filling or draining of a pipeline or piping system. This valve will open to relieve negative pressures whenever water column separation occurs. Applications Pump stations: after the pump and after the check valve Downstreem (after) and upstreem (before) shut-off valve After deep-well pump On long water supply lines At peaks alon the line At the end of lines Before water meter On strainers and filters Valve Selection The air valve is available: With 1/2, 3/4", 1", 2" male NPT, BSPT connections, as requested. With a ball valve tap BSPT/NPT male connection upon request. Vacuum check - The valve is available as a valve that will only release air from the system and will not admit air to the system when under pressure condition occur. This feature is accomplished by the addition of a check valve inserted in the air outlet. 12
Operation The air & vacuum component, with the large orifice, discharges air at high flow rates during the filling of the system and admits air into the system at high flow rates during its drainage and at water column seperation. High velocity air, should not blow the float shut. Water will life the float and cause sealing of the valve. At any time during system operation, should internal pressure of the system fall below atmospheric pressure, air will re-enter the systems, preventing down-surge and cavitation. The smooth release of air prevents pressure surges and other destructive phenomena. Admitting air in response to negative pressure protects the system from destructive vacuum conditions, prevents damage caused by water column separation. Air re-entry is essential to efficiently drain the system. The automatic small orifice air release component releases entrapped air in the pressurized systems. Pockets of accumulated air may cause the following destructive phenomena: Impediment of effective flow and hydraulic conductivity of the system along with a throttling effect as would a partially closed valve. In extreme cases this will cause complete flow stoppage. Accelerate cavitation damages. High pressure surges. Accelerate corrosion of metal parts. Danger of high-energy burst of compressed air. Inaccuracies in flow metering. As the system starts to fill, the valve functions according to the following stages: 1. Entrapped air is released by the valve 2. Liquid enters the valve, lifting the float which draws the "seal plug" to its sealing position. 3. Entrapped air, which accumulates at peaks along the system (where combination air valves should be installed), rises to the top of the valve, which in turn displaces the liquid in the valve's body. 4. The float descends, peeling the "rolling seal", the smaller orifice opens and the accumulated air is released. 5. Liquid penetrates into the valve and the float rises unrolling the rolling seal to its sealing position. When internal pressure falls below atmospheric pressure (negative pressure): 1. Both orifices will be immediately unplugged and the float drops away. 2. Air is admitted to the system. Main Features Working pressure range: 0.2-16 bar (3-230 psi.) Testing pressure: 25 bar (360 psi.) Working Temperature: 60 C Maximum instantaneous working temperature: 90 C Light, simple and reliable structure. Prevents premature closing: The valve discharges air at high velocity, exceeding 11 psi differential pressure. The orifice of the automatic continuous acting valve is larger than in any other air release valve of it's kind, therefore it discharges air at higher flow rates. The size of the automatic orifice makes its obstruction by debris most unlikely. The valve design - rolling seal mechanism: is less sensitive to pressure differentials than a direct float seal. It accomplishes this by having a comparably large orifice for a wide pressure range (up to 16 bar). The body is made of high strength plastic, and all operating parts are made of specially selected corrosion resistant materials. Due to its light weight, the valve may be installed on plastic piping systems, as well as other lightweight piping. A threaded drainage outlet enables removal of excess fluids (1 1/2" in the 2", 3/8" in the 3/4", 1") 13
Project (tender) Specification Type Combination air valve Operation -Kinetic component The valve must discharge air at high velocity during filling of the system and admit air during its drainage. The valve should be designed to prevent premature closing and discharge air. -Automatic component The valve will release accumulated air from the system while it is under pressure and operating. Large dimension automatic orifice of at least 804 mm²,attached to the air & vacuum orifice making it less prone to obstruction by debris. The same orifice for a wide pressure range (up to 16 bar). Pressure - 0.2-16 bar (3-230 psi.) Testing pressure: 25 bar (360 psi.) Ends 3/4", 1", 2" male threads NPT, BSP. Body material Reinforced nylon. Drainage outlets For easy removal of excess fluids. Accessories BALL VALVE Shut-off valve Made of brass ATSM B-124 Suitable for: D-040 1" 2", D-040-C 1" 2" FLANGES Made of reinforced nylon / cast nylon Suitable for: D-040 1" 2", D-040-C 1" 2" Diameter 40/50/60 Internal threads: 3/4" 1" 2" Diameter 40/50/65 Internal threads: 3/4" 1" 2" Diameter 80 Internal threads: 2" 3" FREEZE JACKET Made of polyurethan MODEL ONE WAY The D-040 air valve is available: D040-V -With a vacuum guarding, out-only attachment, which only allows air discharge, not allowing air intake (all models). D-040-I -With a vacuum breaking, In-only attachment, which only allows air intake, not allowing air discharge (D-040 2" only). D-040-NS -With a non-slam, discharge-throttling attachment, which allows free air intake, but throttles air discharge (D-040 2" only). 14
Dimensions and Weights Model Dim. mm Weight Gr. Orifice Area (mm2) A B C Auto. Kin. 1, 3/4, 1/2 D-040 P 100 143 3/8 BSP 0.33 7.8 100 D-040 B 100 143 3/8 BSP 0.70 7.8 100 D-040 ST. 100 143 3/8 BSP 0.65 7.8 100 D-040 ST.ST. 100 143 3/8 BSP 1.40 7.8 100 2 D-040-P 180 209 1½ BSP 1.1 12 804 D-040-B 180 209 1½ BSP 2.2 12 804 D-040-ST. 180 209 1½ BSP 2.1 12 804 D-040 ST.ST. 180 209 1½ BSP 3.1 12 804 Air And Vacuum Flow Rate 1/2, Automatic Air Discharge 1/2 Parts list and specification No. Part Material D-040 P / B / ST D-040 ST ST 1. Body Reinforced Nylon St.St. SAE 316 2. Drainage Elbow Polypropylene Polypropylene 3. Seal Plug Assembly 3a. Screws Stainless Steel Stainless Steel 3b. Plug Cover Reinforced Nylon Polypropylene 3c. Rolling Seal E.P.D.M. Viton 3d. Plug Reinforced Nylon Polypropylene 4. Clamping Stem Reinforced Nylon Polypropylene 5. Float Foamed Polypropylene 6. O-Ring BUNA-N Viton 7. Base Reinforced Nylon St.St. SAE 316 / Brass ASTM B124 / St.St. SAE 316 Optional Ball valve Brass ASTM B124 15
D-040 C Combination Air Valve (PATENTED) Dimensions and Weights Air And Vacuum Flow Rate Model Dim. mm Weight Gr. Orifice Area (mm2) A B C Auto. Kin. 1, 3/4 D-040-C 119 150 3/8 BSP 1.7 5 82 2 D-040-C 203 231 1½ BSP 5.4 12 804 D-040-C F 250 233 1½ BSP 7.3 12 804 Automatic Air Discharge Parts list and specification No. Part Material D-040 P / B / ST D-040 ST ST 1. Body Reinforced Nylon Cast Iron ASTM A48 CL.35B 2. Sleeve Polypropylene Reinforced Nylon 3. Seal Plug Assembly 3a. Screws Stainless Steel Stainless Steel 3b. Plug Cover Reinforced Nylon Reinforced Nylon 3c. Rolling Seal E.P.D.M. E.P.D.M. 3d. Plug Reinforced Nylon Reinforced Nylon 4. Drainage Elbow Reinforced Nylon Polypropylene 5. Clamping Stem Foamed Polypropylene Reinforced Nylon 6. Float BUNA-N Foamed Polypropylene 7. O - Ring Reinforced Nylon Buna-N 8. Base 3/4 1 / Brass ASTM B124 Brass 2 / St.St. SAE 316 9. Bolt & Nut (x4) Brass ASTM B124 Optional Ball valve Brass ASTM B124 Cast Iron ASTM A48 CL.35B Steel Zinc Cobalt Coated 16
S-050 PN 16 Automatic Air Release Valve segev pate.pend Description The Automatic Continuous Acting Air Release valve ("High pressure") discharges accumulated air from the system while it is under pressure. This revolutionary valve is the result of development based on many years of experience. The Automatic Continuous Acting Air Release valve is the first of its kind in the world. In spite of its compact and light weight structure, it has a 12mm² orifice that enables it to discharge air at high flow rates and is not exposed to obstruction by debris. Valve Selection Available in male threaded sizes: 1/2", 3/4", 1" - BSP / NPT Vacuum check valve - The valve is available as a valve that will only release air from the system and will not admit air to the system when negative pressure conditions occur. This characteristic is obtained by adding a check valve to the air outlet. Operation The Automatic Continuous Acting Air Release valve, releases entrapped air from pressurized systems. Pockets of accumulated air may cause the following destructive phenomena: Impediment of effective flow and hydraulic conductivity of the system along with a throttling effect as would a partially closed valve. In extreme cases this will cause complete flow stoppage. Accelerate cavitation damages. High pressure surges. Accelerate corrosion of metal parts. Danger of a high-energy burst of compressed air. Inaccuracies in flow metering. The valve functions while the system is under pressure, according to the following stages: 1. Liquid fills the system and enters the valve. 2. The float rises and rolls the rubber sealing band to its sealing position. 3. Entrapped air, which accumulates at peaks along the system, rises to the top of the valve, which in turn displaces the liquid in the valve's body. 4. The float descends, peeling the rolling seal the orifice opens, and the accumulated air is released. 5. Liquid reenters the valve and the float rises, rolling the rubber sealing band to its sealing position. Note: Automatic Continuous Acting Air Release valves are designed to release air as it accumulates at peaks of pressurized systems. They are not normally recommended for vacuum protection to valve large volumes of air, because of the inherently small orifices. For this purpose kinetic air valves have much larger orifices. However Automatic Continuous Acting valves will permit air to re-enter under vacuum conditions. If this is not desirable specify Vacuum check valves. Main Features Working pressure range: 0.2-16 bar. Testing pressure: 25 bar Maximum working temperature 90 C. The larger than usual orifice enables it to discharge air at higher flow rates than other Automatic Continuous Acting Air Release valves of its kind. The enlarged orifice is not exposed to obstruction by debris. The valve's design Rolling Seal Mechanism, is less sensitive to pressure differentials than a direct float seal. It accomplishes a comparably large, orifice for a wide pressure range (up to 16 bar). Light weight, simple and reliable structure. The body is made of high strength plastic, and all operating parts are made of specially selected corrosion resistant materials. A drainage outlet enables removal of excess fluids. 17
Dimensions and Weights Air And Vacuum Flow Rate Model A B Dimensions mm internal C externa Weight Kg. Orifice Are mm2 S-050 P 87 140 1/8 18 0.3 12 S-050 B 87 140 1/8 18 0.65 12 S-050-C 85 148 1/8 15 1.65 12 S-052 85 148 1/8 15 1.65 9 Parts list and specification No. Part Material 1. Cover 16 bar Cast Steel ASTM A-48 CL35B 25 bar Sphero Nodular ASTM A-536-60-40-18 2. Body Reinforts Nylon 3. Drainage Outlet S-050 Polypropylene S-050-C/S-052 Brass ASTM B-124 4. Rolling Seal E.P.D.M. 5. Clamping Stem Reinforts Nylon 6. Float Foamed Polypropylene 7. O-Ring BUNA-N 8. Base S-050 Reinforts Nylon / Brass ASTM B-124 S-050-C/S-052 Brass ASTM B-124 9. Strainer Nylon 18
NR-010 PN 10 Check Valve Applications Green houses water supply Irrigation systems Corrosive and aggressive fluids Swimming pools and water tanks Water supply systems Main Features Working pressure: 10 bar Working Temperature up to 60 C. Unobstructed flow structure Low head loss Dry Reed micro switch available Advantages and Benefits Compact structure Maintenance free Includes flange rubber seals Improved sealing system Non-corrosive materials Cost effective product NR-010 LS 19
Dimensions and Weights Head Loss Nominal Size Dim. mm A B C Weight Gr. NR -010 3 75 172 132 571 NR -010 LS 3 75 219 132 580 NR-010 4 85 191 151 732 NR-010 LS 4 85 238 151 740 Parts list and specification No. Part Material 1. Body Reinforced Nylon 2. Disc. Reinforced Nylon 3. Seal Rubber E.P.D.M. 4. Bolt (x2) Stainless Steel SAE 316 5. Shaft Stainless Steel SAE 316 6. Shaft Holder Acetal 7. Pusher Acetal 8. Spring Cover Reinforced Nylon 9. O-Ring BUNA-N 10. Spring Stainless Steel SAE 316 11. Arrow Polypropylene 12. Flange Seals Rubber E.P.D.M. 13. Spring Cover Reinforced Nylon 14. Magnet (x2) 15. Magnet Holder Acetal 16. Dry Reed Limit Switch 20
NR-020 PN 16 Check Valve Features A combination air valve (kinetic & automatic) that includes a shut-off valve as an integral part of valve's body. Especially applicable for underground chambers and deep wells Minimum height and width dimensions. Upper operational access to shut-off valve. Optional operation by extended-shaft from without the chamber. NRS valve (Non Raise Stem) Fixed height of shut-off valve. When the shut-off valve is closed, the complete internal mechanism can be removed easily upward as a separate assembly, allowing for easy maintenance. Automatic air release up to 450 m³/h. Saves energy and reduces operation costs. Three Independent Automatic Air release valve working according to A.R.I patented rolling seal principal. Dramaticaly reduces the possibility of obstruction by debris. The Automatic units are implanted inside the kinetic float and are protected from outward damage. An inner "air pillow" protects the valve against damage from freezing. Dynamic design allows high velocity air discharge, Preventing premature closing. Maximum rate: 80mm - up to 3,400 m³/h 100mm - up to 4,500 m³/h "Anti-Slam" shutting as a consequence of "air pillow" inside valve's body that acts as a buffer. Standard cast iron body - baked polyester coating. Working pressure range: 0.2-16 bar. (3-230 psi). Available in 3" (80mm), 4" (100mm) Flanges are available in BS/ISO/ANSI standards. Option Screen outlet. Drainage outlet. NR-020-FV PN 16 NR-020-LS PN 16 21
Dimensions and Weights Head Loss Nominal Size Dimensions mm Weight Kg. A B C D E NR-020 NR-020 LS NR-020 FV 3 (50 mm) 77 140 200 282 203 1.15 1.5 1.5 4 (80 mm) 85 157 210 292 226 1.6 2.0 2.0 6 (80 mm) 107 220 307 389 291 3.15 3.6 4.0 8 (80 mm) 127 273 342 424 335 6.5 6.9 7.2 Parts list and specification No. Part Material 1. Spring Chamber Reinforced Nylon 2. Spring Stainless Steel Sae 302 3. O-Ring BUNA-N 4. Spring Seat Acetal 5. Indicator Stem Bushing Stainless Steel Sae 303 6. Flap Shaft Stainless Steel Sae 316 7. Roller Shaft Stainless Steel Sae 316 8. Roller Acetal 9. Flap Reinforced Nylon 10. flap Seal E.P.D.M. 11. Cover Bolts Stainless Steel Sae 304 12. Disc Stainless Steel Sae 303 13. Bolts Stainless Steel Sae 304 14. Cover Seal E.P.D.M. 15. Body Reinforced Nylon 16. Cover Reinforced Nylon 22
NR-020 ls 3-6 with limit switch Parts list and specification No. Part Material 1. Limit Switch 2. Plastic Cover Reinfoced Nylon 3. O-Ring E.P.D.M 4. Indicator Stem Bushing Teflon 5. plastic Nut Reinforced Nylon 6. Spring Chamber Reinforced Nylon 7. Spring Stainless Steel Sae 302 8. Position Indicator Stem Stainless Steel Sae 316 9. O-Ring BUNA-N 10. Spring Seat Acetal 11. Shaft bushing Stainless Steel Sae 303 12. Shaft Stainless Steel Sae 304 13. flap Shaft Stainless Steel Sae 316 14. Roller Acetal 15. Flap Reinforced Nylon 16. Flap Seal E.P.D.M 17. Cover Bolts Stainless Steel Sae 304 18. Disc Stainless Steel Sae 303 19. Disc Bolts Stainless Steel Sae 304 20. Cover seal E.P.D.M 21. Body Reinforced Nylon 22. Cover Reinforced Nylon NR-020 8 Parts list and specification No. Part Material 1. Spring Chamber Reinfoced Nylon 2. Spring Stainless Steel Sae 302 3. O-Ring BUNA-N 4. Spring Seat Acetal 5. Plug Brass 6. O-Ring BUNA-N 7. Roller Acetal 8. Shaft Stainless Steel Sae 304 9. flap Shaft Stainless Steel Sae 316 10. flap Aluminum 11. O-Ring BUNA-N 12. Body Aluminum 23
Installation Guide Characteristics of water systems used in agriculture and landscaping: High frequency changes in flow characteristics. Water must be treated (filtered) in the field. Chemicals and fertilizers are injected into the irrigation system. It is often necessary to use fragile and often complex equipment and instrumentation. Large differences in the characteristics and materials used to manufacture pipes, connectors and accessories. INSTALLATION AT PUMPS The DG-10 combination (double) air valve must be installed directly after the pump and before the pump s non-return valve. Water pumped from an independent supply such as a well, stream or reservoir requires the admission of air into the pump and suction pipes. This air will continue to disperse in the system during pump operation. Now it works: When the pump begins operating, large volumes of air are released through the kinetic orifice in the air valve. Water entering pushes the float that closes the orifice and opens the check (nonreturn) valve. When the pump is shut down or stops working for any other reason, air admitted through the kinetic orifice acts as a vacuum breaker and protects the pump, connectors, accessories and seals from damage caused by sub-atmospheric (negative) pressure. The small automatic air valve continues to release air while the pump is working and the line is pressurized. At its location before the check valve, it prevents cavitation damage to the sealing face in the check valve caused by the presence of small air bubbles in the water. It is a good idea to install a DG-10 air valve after the pump s check valve. This air valve will allow the admission of air when the pump is stopped or shut down and when the check valve closes. It also releases air when the water pressure returns after a sudden drop in head. INSTALLATION IN LOCATIONS WITH CHANGING PRESSURES It is reccomended to install a 1 DG-10 air valve in areas with fluctuating pressure: pressure regulation valves, pressure release valves and where pipe diameter changes. These are the areas where air pockets form and might be released into the line. As the pipe is filled, these areas can be problematic if not provided with an adequate air release system. If pressure fluctuations are not too extreme, the SG-10 air valve will suffice when installed downstream and close to these sensitive areas (close to an accessory or disturbance). INSTALLATION AT THE HIGHEST POINTS IN A LINE It is reccomended to install a DG-10 air valve at all the highest points in each line where flow speeds drop below the critical speed for air movement. The kinetic orifice, installed at line high-points, releases air as the line is filled and admits air during line draining regardless of whether the process is controlled or not (pipe burst or collapse). The automatic air valve releases air accumulating at high points when the line is pressurized during regular operations. Where the land topography is relatively flat, the line has shallow slops and the high points are relatively close, The SG-10 automatic air release valves can replace DG-10 valves at some of the high points. INSTALLATION ON LONG LINES On long lines, DG-10 or SG-10 valves should be installed every 500 meters to 800 meters. Install DG-10 valves on both sides of long sections of horizontal pipe. 24
INSTALLATION CLOSE TO A MAIN LINE VALVE When the line is pressurized and the valve is closed, than an air valve should be installed before main line. Installation of the air valve will protect the valve plate against cavitation damage caused by small air bubbles. If the end valve will be closed when the line is filled, which will slow down the filling process, install a DG-10 valve before the main valve on lines with large diameters and flow volumes. The additional installation of DG-10 air valves after main line valves will protect the line in the negative pressure (vacuum) conditions created when the line is closed suddenly. This valve will also assist in controlling the filling process when the main valve is open. INSTALLATION WHERE A LINE CROSSES UNDER A ROAD OR DITCH It is reccomended to install a DG-10 air valve whenever a large diameter pipe has sharp changes of angle when crossing under a road or ditch. When the crossing point is wide and / or deep, install the air valve at the uppermost point of the angle change on both sides of the road. If the crossing point is short and shallow, it is sometimes possible to install only one DG-10 air valve on the uppermost point of angle change on the downstream side of the crossing point. INSTALLATION BEFORE WATER METERS AND AUTOMATIC REGULATORS Install a DG-10 air valve upstream from a water flow meter and automatic flow regulator. Given that the water flow regulator is a special type of main valve, install another DG-10 air valve after the regulator. Air can flow at speeds up to 29 times faster than water flow speeds. Air moving fast through a water meter or the unit that measures flow in the automatic regulator will spin the impeller used to measure flow at very high speeds. These instruments, which cannot differentiate between water and air will register very high flow volumes that do not in fact exist. Another problem created under such conditions is the inadequate supply of irrigation water to the fields because the measuring instruments record high flow rates. Water both cools and lubricates as it turns the impellers inside the measuring equipment. Air moving through the measuring unit at high speeds causes the impeller to overheat and prevents watercooling, which then results in high temperature damage that can even melt the plastic impeller. Installation of an air valve before the measuring equipment will protect the meter from heat damage and false readings. INSTALLATION ON FILTERS A. On gravel filters, it is reccomended to use a DG-10 air valve, and on screen or ring filters, it is reccomened to install SG-10 air release valve. B. Filtering efficiency - Air flowing through an automatic back flashing filter systems disrupts the filters hydraulic functioning, and creates differencial ressure in the filter consequently, the filter system is flushed frequently, which wastes water and lowers system efficiency. 25
INSTALLATION ON DRIP IRRIGATION SUPPLY LINES AND LATERALS It is reccomended to install a DG-10 air valve directly on the vertical pipe rising from the main line at the head system. Install an AV-010 Guardian model air and vacuum air valve on an irrigation and dripper system after the submain valve. If the lateral line is long, install a number of Guardian valves along the line, with emphasis on the highest points in the field and along the line. Guadrian air and vacuum valves are required to prevent negative pressure in the line (vacuum) which can cause the drippers sucking up mud and dirt when flow stop. INSTALLATION AT PIPE ENDS It is reccomneded to install a DG-10 air valve at the end of each line, before a main valve or submain valve. 26
INSTALLATION IN AN IRRIGATION OR LANDSCAPING SYSTEM CONTROL CABINET It is reccomended to install a DG-10/DT-040 (depending on the flow rates) valve on the line as it enters the control cabinet and before the main valve (electrical or hydraulic valve). Install an SG-10 valve before the water meter and the filter. Install an RP-500 Backflow Prevention Unit with a diameter of 1 or 3/4 before a herbicde filter or fertigation pump. INSTALLATION AT THE MAIN LINE VALVE CONTROL SYSTEM It is reccomended to install a combination DG-10 air valve directly onto the vertical pipe at the Main Line Valve Control System. This will ensure control of air in the water supply and protection for the other accessories in the control system and in the downstream flow, including protection for water meters. It is reccomended to install an AV-010 Guardian model air valve after the tap on the lateral feeding the dripper lines. 27
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