TECHNICAL VALVES PRINCIPLE OF OPERATION DOROT PLASTIC VALVES. 3-Way Control System. 2-Way Control System T48

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2 DOROT PLASTIC VALVES PRINCIPLE OF OPERATION -Way Control System The main valve is controlled by a manually, electrically or pressure actuated selector that: (1) Introduces the upstream pressure or an external pressure source to the valve s control chamnber, thus pressing the valve diaphragm from the top to a closed position. (2) Opens the valve by relieving the pressure from the control chamber and enabling the internal pressure in the line to push the valve diaphragm up and creating an unresticted, full-flow passage. () Shutes all passages to and from the control chamber, thus keeping the main valve in a fixed poition. This position does not exist in devices used for ON / OFF control applications but is necessary in modulating valves. 2-Way Control System A control system that consists of two restrictions: (a) A fixed restriction at the upstream side of the control system (nozzle or needle valve). (b) ON / OFF device (valve, relay or solenoid) or a modulating pilot-valve with a larger passage than restriction a that is installed at the downstream side of the control system. The main valve position is affected by downstream pilot-valve b in the following ways: (1) When the pilot-valve is closed, no water can be vented to the downstream and the main vlave is closed by the upstream pressure, introduced into the valve control chamber through the restriction a. (2) Opening the vlave is enabled when the pilot b is fully open and allows the drainage of pressure in the control chamber to the downstream. At this position the pressure in the control chamber nearly equals that of the downstream. () Throttling pilot-valve b so the flow running through it equals the flow entering through the restriction a, keeps a fixed volume of water in the control chamber and the main valve in a fixed position. T48

3 DOROT PLASTIC VALVES DOROT - 75 VALVE The Dorot-75 series consists of plastic membrane valves for agricultural use. They are resistant to fertilisers and have a large free passage (and therefore a high flow rate and/or low resistance). The membrane minimises the risk of water shock and allows for accurate regulation, even at low flow rates. The Dorot-75 2-way valve is the economical version which is often used for sprinkling and drip irrigation. The unique built-in non-return valve keeps the valve closed even if there is no pressure in the line and thus prevents annoying trickling during start-up. The stand-alone is a special version featuring an automatic device which is fitted directly on the valve and which allows for individual control of the valve, independent of a central control system. A 2-way pulse solenoid is used for battery control by the automatic device. The -way version is used if large flow rates are required or if dirty water is used. The Dorot-75 -way valve also features an industrial solenoid which ensures improved reliability and allows for external pilot pressure (air for example). Basic valves can be used for the construction of pilots, floats etc. and for (hydraulic) remote control. The Dorot 2-way and -way valves are fitted with a throttle, an electric solenoid and a manual control device. The Dorot-75 series is BSPT female threaded. Technical Specification Diameter 2-Way: /4 - Diameter -Way: 1 1/2 - Basic: 1 1/2-2-Way Pulse: Optional: /4 - (for 9V battery) Without throttle 2-Way with G80 (industrial solenoid) Air-controlled (-Way & Basic) 24V DC/AC (50/60Hz); 20V as stand-alone with automatic device /4-1 Basic Max. Pressure: 10 Bar (at 20 o C) Max. Temperature: 60 o C (at decreasing max. pressure) Housing Material: Reinforced Polyamide Membrane: Natural Rubber Spring: INOX 02 Bolts: INOX 04 HEADLOSS CHART psi mwc WAY CONTROL MODEL 75, 95, / /2 75- (BLUE AREA INDICATES RECOMMENDED OPERATING RANGE) 95/ WAY ELECTRIC CONTROL-MODEL 75 psi mwc ƒ" 1" " 1å " 2" 2å " m /h gpm m /h gpm T49

4 DOROT PLASTIC VLAVES DOROT - 80 VALVE The hydraulic Dorot-80 valve offers substantial improvements when compared with existing valves. It has been specially designed for the greenhouse industry and is supplied as a right angle model (Dorot-80-AT), and from mid-2005 also as a straight model (Dorot-80-T). The main difference versus the well-known Dorot-75 is the shape of the membrane. The Dorot-80 is a globe type valve, whereas the Dorot-75 is a Gal type valve (with a freely moving membrane). The membrane of the Dorot-80 is entirely supported, whether open or closed, which extends its life and increases reliability. The wide internal passage of the Dorot-80 provides a higher flow rate when compared with similar valves. The Dorot-80 is fitted with a non-return valve and is available in 2-way or -way versions (mid-2005). Its special characteristics render the new Dorot-80 ideally suitable for sprinkling. The right angle design facilitates compact incorporation and the non-return valve prevents annoying trickling during start-up of the system. Thanks to the high flow rate, the valve is ahead of its field in ebb and flood systems and large drip sections. The 80-A is the right angle version in 1 1/2 or 2, while the Dorot-80 is straight. The extension T stands for Throttle. The 2-way version is supplied with an agricultural or industrial solenoid (G80), the -way version with an industrial solenoid (Baccara). The Dorot-8-T-1 is a special quick-closing version, intended for Fogger systems for example. Opening and closing times are approx. 1 second. Benefits of Dorot-80 Features a higher flow rate and less pressure loss than comparable valves Insensitive to clogging due to large inlet filter in control flow. The filter can be cleaned manually without opening the valve The labyrinth provides wide passages for pilot pressure, thus further minimising the sensitivity to clogging The non-return valve prevents partial opening of the valve when the inlet pressure fails* Adjusting screw for flow rate control (throttle). The knob can be removed in order to prevent wrongful adjustment during use Large, simple manual control device with three positions: automatic-open-close: the valve can also be closed manually with an energised solenoid Improved control characteristic Pressure reducing pilot for direct incorporation in the valve Nuts locked in housing, cannot get lost. * Only in 1 1/2 and 2 2-Way versions. Technical Specification Operation: 2-Way -Way Design 80 A: Right angle: 1 1/2-2 80: Straight: 1, 1 1/2, 2 -T: Throttle Flowrate 1 : m / hour 1 1/2-2 : 1-40m / hour Optional: Max. Pressure: Max. Temperature: Housing Material: Seals: Steel Components: 24VAC-DC (agricultural sloenoid) Other voltages 10 Bar 60 o C (at decreasing max. pressure) Glass-fibre Reinforced Polyamide EPDM and NR INOX T50

5 DOROT PLASTIC VALVES 80-1, 80-/4 IRRIGATION VALVES T51

6 DOROT PLASTIC VALVES 80 SERIES 11/2 AND 2 SPECIFICATION Solenoid Valve (2-way model) Position Manual Override (2-way model) Flow Control Stem (optional) Labyrinth Restrictor (2-way model) Diaphragm Support Rings Diaphragm & Plug Trim Integral SST Filter It is recommended to avoid pressure losses across the valve exceeding 0.5 bar. T52 The Dorot-80 valves can be installed in any required position though upright or vertical with solenoid up installation is preferable in order to allow air to escape and to prevent accumulation of dirt behind the solenoid core. The air pressure for air-controlled operation must not exceed the pipe pressure by more than 0.5 to 1 bar when the valves are closed. The air used must be free from lubricants. If there is a chance of frost, the water must be drained from the valves (and solenoids).

7 DOROT PLASTIC VALVES DOROT - 95 / 96 PVC VALVES The Dorot-95/96 series consists of U-PVC valves which are suitable for high flow rates and/or low resistances. They are resistant to fertilisers and have a free passage (and therefore a high flow rate and/or low resistance). The membrane minimises the risk of water shock and allows for accurate regulation. Special, soft membranes are available for applications with minimal pressure downstream of the valve and minimal working pressure (0.5 bar). The 95/96 series is generally supplied as a basic valve with a -way industrial solenoid, which can be used for the construction of manual control devices, pilots, floats etc. and for (hydraulic) remote control. A PR-pilot (29-100) can be used as a throttle and for automatic pressure regulation. The Dorot-95-PVC valve is supplied with female thread, the 96-series with a glued connection. (90 or 110 mm). Technical Specification Diameter 95: Diameter 96: Optional: Control Signal: Optional: (Female threaded) mm 160mm 24V DC/AC (50/60Hz); 20V Air-controlled (max. 1.6mm solenoid nozzle) Manual As a Float Valve As a Control Valve with Pilot Soft Membrane (low-pressure app.) Max. Pressure: 8 Bar (at 20 o C Min. Pressure: 1 Bar (0.5-1 Bar soft membrane rec.) Max. Temperature: 40 o C (at decreasing max. pressure) Weight: 4.2Kg Housing Material: upvc Membrane: NR Spring: INOX 02 The Dorot-95/96 series can be installed in any required position though upright or vertical with solenoid up is preferable in order to allow air to escape and to prevent accumulation of dirt behind the solenoid core. The air pressure for air-controlled operation must not exceed the pipe pressure by more than 0.5 bar when the valves are closed. The air used must be free from lubricants. For comparatively low flow rates (up to approx. 70m/h), the solenoid vent can be connected to the downstream plug or the valve, which will substantially shorten the closing time, though there may be some effect on the resistance. If there is a chance of frost, the water must be drained from the valves (and solenoids). T5

8 DOROT SPARES DOROT SOLENOIDS Dorot supplies a complete range of agricultural and industrial solenoids for 2-way and -way valves. The economical, low capacity 2-way solenoids are mounted directly on 2-way valves. Industrial 24V or 20V 2-way solenoids are optionally available (G80, standard on Dorot-80 valves). -way solenoids can be directly mounted on Dorot -way valves or on their own sub-base on basic valves. When mounted directly, the valve is always NC (Normally Closed). When mounted on a basic valve, a NO (Normally Open) or NC solenoid can be used to make the valve NC or NO respectively. NO valves (with NC solenoid) are used if the valves are normally open and will only close upon a pilot signal being given. A special 2.5 W -way solenoid (with special operator and core) is available for applications in which the solenoid is energised for a long time. The components of a -way solenoid are partly interchangeable (see table). Standard solenoids are supplied with a 1.6 mm nozzle in the operator for the 75 series, and with a 2.4 mm nozzle for the PVC series. Other applications are possible (see table). All industrial solenoids are fitted with an INOX operator (core armature). Technical Specification 2-Way Agicultural: 24VAC 50Hz (2.2 W) (Dorot Solenoid) 24VDC (4.5W) 9V pulse (Latch battery)* *Please note that a separate manual control device is required. Optional: (Gem Solenoid) Optional: Connections: Optional: 24VAC 50Hz (8W**) 24VAC 50/60Hz (2.5W) 24VDC (10W**, 2.5W) **Standard until approx. Summer 2001 Larger nozzle diameters (4mm) Solenoids for special applications 1 x 1/8 (female thread) and 2 x 1/4 (female thread) x 1/8 (female thread) T54

9 DOROT SPARES DOROT SPARE PILOT PILOT VALVE (BLACK, -WAY) USED FOR: PRESSURE REDUCING VALVES (PR) ADJUSTMENT RANGE SIZES: 4 " - 4" SPRING NO. COLOR RANGE 54 (STANDARD) GREEN m psi 72 YELLOW 5-25 m 8-5 psi m 65 RED 0-90 psi MAX. LINE PRESSURE: 100 m (140 psi) COMPONENTS 1 ADJUSTING BOLT - 10 O-RING SPECIFICATIONS COMPONENT NO. 1, 5, 6, 4, 9, 11, 12, 1, , 7,16, MATERIAL BRASS PLASTIC NITRILE RUBBER SST SST, NATURAL RUBBER, PLASTIC NATURAL RUBBER LOCKING NUT - SPRING IDENTIFICATION RING 4 BONNET - 5 BONNET NUT - 6 SPRING DISC DIAPHRAGM ASSEMBLY - DIAPHRAGM BOWL - 11 SEALING DISC KIT - 12 PORTS SELECTION BODY - 1 PLUG SEAT - 14 PLUG - 15 BODY - 7 SPRING - 16 BRACKET 8 " BRACKET 8 "- T55

10 DOROT METAL VALVES 44 SERIES Hydraulic Performance Valve Size Max. Flow Continuance Max. Flow Intermittent Minimal Flow mm LF inch / / / m /hr gpm m /hr gpm m /hr gpm Kv m 1 bar Cv 1 psi Kv* m 1 bar Cv* 1 psi * High pressure models T56

11 DOROT METAL VALVES Headloss Chart psi mwc /4 1 1/2 1 1/2, 2 2, , , 18 16, , m /hr gpm Cavitation Data Upstream Pressure psi bar Cavitation zone Safe zone for Bronze valves Safe operation zone Downstream Pressure bar psi MODEL SIZE MM INCH Inch mm L H L H 1 1/ /8 5/8 MODEL /8 4 1/2 2 1/ / / /8 51/8 T57

12 DOROT METAL VALVES BACKFLUSH VALVES Mode of Operation The black-flushing control valves are activated by system water pressure or by pneumatic pressure source. Operation is initiated by an electric solenoid, hydraulic relay or manually by a way selector. The back-flush valve has a Normally Open (N.O.) filter port and a Normally Closed (N.C.) drain port. Each port has it s own sealing seat but they share a common stem activating diaphragm. The valve operates as a mutually integrated unit. When one port is open, the other is closed, by this permitting the back-flush valve to perform it s two modes of operation T58

13 DOROT METAL VALVES MODEL 51/52 INTERNAL PARTS FILTRATION MODE FLUSHING MODE 57/58 T59

14 BERMAD VALVES FLOW CONTROL VALVES The BERMAD 200 Series plastic control valves range from /4 to 2 in size, in either globe or angle pattern. These control valves provide superior hydraulic performance, constituting as they do, the state-of-the -art in hydraulics and in plastic technology. Features Constructed of corrosion-resistant, high engineering plastics, synthetic rubber and stainless steel parts. Very high flow rate with very low head loss. Operation over a wide range of pressures. Smooth valve opening and closing prevents pressure surge hazards. Self-cleaning orifice on electric models provides reliable valve operation, even with brackish water. Flow control handle for water flow adjustment. Manual solenoid override for opening valves in case of power failure without external water spill. High performance solenoid with low electrical power consumption. Wide range of models of electric and pressure regulating control valves. Technical Specifications Valve Pattern: Globe, Angle & Y-pattern (1 ) Sizes: /4, 1, 11/2 & 2 End Connections: Female threaded BSP, NPT Pressure Rating: ISO: PN 10 ANSI: Class 125 Operating Pressure Range: Bar ( psi) Temperature Range: Water up to 80 C (180 F) Electrical Data: Standard: Voltage: Current: 24V AC (50-60 Hz) Holding 0.20A, Inrush 0.40A Optional Voltages: 6V DC, 12V DC, 24V DC, 12V AC, 24V AC Materials: Body & Cover: Nylon Reinforced Metal Parts: Stainless Steel Diaphragm: Natural Rubber Seals: Buna-N & NR Dimensions and Weights Pattern Globe Size DN inch ¾ 1 1½ 2 L mm H mm h mm W mm Weight Kg T60

15 BERMAD VALVES Flow Chart Hydraulic/Electric Control Valve Assembly T61

16 BERMAD VALVES 100 SERIES Durable industrial grade valve design and construction uses glass-filled Nylon material to meet rough service conditions. Ultra-high flow capacity with a minimal pressure loss. Valve design for service on a wide range of pressure and flow conditions, from dripping to maximum flow conditions. Simple design with few parts guarantees in-line inspection and service. Positive guided valve plug provides accurate motion and smooth regulation. Avoids chattering and slamming closed. Versatile end connection allows mix of different sizes and connection types. Female thread, Flanged or PVC Slip-on Glue or Grooved adapter (as add-on option). Articulated flange connections isolates the valve from line bending and pressure stresses. ELECTRIC VALVE, MODEL 110-2W-N Look-through design Straight through flow results in ultra-high flow capacity with minimum pressure loss. T62

17 BERMAD VALVES Technical Specifications Sizes: 2,, 4 (DN 50, 80, 100) Ends Connections: NPT ; BSPT female threads Pressure Ratings: ISO PN 10 ; 150 PSI ; JIS 10K Working Pressure Range: bar ; psi Temperature: Water up to 80 C ; 180 F Materials Body, Cover, Valve Plug: Diaphragm: Seals: Spring: Cover Bolts: Glass Filled Nylon NBR [Buna N], Nylon Fabric Reinforced NBR [Buna N] Stainless Steel Stainless Steel T6

18 NOTES T64