VAG PICO® Diaphragm Valvefor automatic and simple water regulation

Basic valve closedThe control pilot does notdrain liquid. The medium isbeing transported in throughthe inlet side: the main valvecloses progressively.

Basic valve openThe control pilot drains moremedium than is being addedthrough the restriction: themain valve opensprogressively.

Basic valve controlsWhen a balance betweensupply and drain of mediumis reached then the mainvalve is hydraulically placedin the correct position.

NoteIn all situations the mainvalve follows the move-ments of the control pilot

) ( = restriction

Basic valve closed Basic valve regulatesBasic valve open

) ( ) ( ) (

flow flow flow

VAG PICO® Diaphragm Valves

VAG PICO Diaphragm Valves consists of a hydraulicallyoperated main valve and a pilot circuit.The main valve is the basis for all control valve types andconsists of three main parts:

• body• cover• diaphragm assembly

The valve can control a range of applications simply bychanging the pilot circuit. These includes pressurereduction & sustaining, level control, pressure relief andmany more functions. In most cases functions can beadded at a later stage without removing the valve from theline. This opens a wide range of possibilities. The onlymoving parts in the main valve is the diaphragm assembly,which are guided by an exchangeable bearing in the coverand the valve seat. The diaphragm, a resilient syntheticrubber, which is clamped in between body and cover,separates the control pressure from the line pressure.Extensive research and development looking at the ratiobetween the surface areas of the diaphragm and the sealensures that the valve assembly will close if the pressure inthe cover chamber and the inlet chamber are the same. Theseal on the diaphragm assembly attached at the valve seatguarantees a perfect and long lasting seal, allowing thecontrol valve to act as a leak tight on/off valve at the sametime. The pilot circuit is equipped with a high capacitystrainer, which ensures that the pilot valve will not becomeblocked. The valve needs no lubrication, has a simpledesign and therefore requires little maintenance. Also a longservice life is assured. Any work that is required can bedone with the valve in position and therefore maintenancecan be undertaken on site. Due to this fact down times areminimized.

Mode of OperationThe sectional drawings below shows a main valve equippedwith a simple on/off control pilot, mounted in the controltubing connected to the outlet side, and a restriction orneedle valve on the inlet side of the valve. The pilot valvecan perform three tasks:• open• close• control

VAG PICO® Main Valve

For all types of the VAG PICO Diaphragm Valve, the main valveforms the basis of the various models and functionalities.Due to this, only one single main valve is needed for thecombination of different valve functions and the valve can beequipped according to your specific, individual requirements.This versatile valve design provides a lot of benefits to ourcustomers:

• Minimum friction coefficientsThe diaphragm-actuated motion rod allows low-friction motion with very low hysteresis.

• Low maintenance expenditureOnly one moving interior part ensures reliable function and requires little maintenance.

• Epoxy coatingAll cast parts are epoxy-powder coated on the inside and outside.

Bonnet

Spring

Hexagonalscrew

Diaphragmretaining disk

Retaining ring

Seat ring

Stem

Position indicatorwith venting screw

Bearing bush

Stem nut

Diaphragm

Sealing ring

Body

Features and design of the main valve

VAG PICO Main Valve

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VAG PICO® Control Circuit

Features and design of the control circuit

The components of the control circuit assembled to the mainvalve implement the functions of the diaphragm valve.

The stainless-steel pilot valve works according to the'balanced pressure principle', which means that changes ofthe system pressure do not affect the adjusted set-pointvalue.

The filter installed in the control circuit is a high-capacityfilter which can be purged and is equipped with aninspection glass.

The integrated control unit allows the separate adjustment ofthe opening and closing speed.

Stainless-steel casing controlunit for the separateadjustment of the reactionvelocity for “Close” and“Open”

VAG PICO with control circuit

VAG PICO Pilot Valve VAG PICO Control UnitFor separate adjustment of the

opening and closing speedPlastic bonnet

Stainless steel body

Stainless steel body

Opening speed (OS)

Closing speed (CS)

Stainless steel throttling orifice

Stainless steel filter casing

Stop valve for manual purging

Stainless steel pilot valve body

Manometer for easiercommissioning

Piping and screwconnections made of

stainless steel

High-capacity filterequipped with an

inspection glass for easyidentification of the degree

of soiling. Size of filteringsurface 50 cm² min.,

perforation 0.5 mm max.

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Pressure reducing / sustaining valve type 02.03 (S)

Pressure sustaining and relief valve which reduces a higherinlet pressure to a constant lower outlet pressure. Thevalve closes, however, to retain the inlet pressure in casethe supply pressure drops below a predetermined value.Pressure reducing function: 2 - 12 barOn request: 0,4 - 2 bar

1 - 5,5 bar5 - 21 bar

Pressure sustaining function: 3 - 21 barOn request: 0,1 - 6 bar

Pressure reducing valve type 02

Pressure Reducing Valve reduces a higher upstreampressure to a constant lower downstream pressure.

The standard pressure range is: 2 - 12 barOn request: 0,4 - 2 bar

1 - 5,5 bar5 - 21 bar

Pressure reducing valve with bypass type 02 (LF)

This pressure reducing valve is additionally equipped witha bypass for low volume control.

Pressure Control

Pressure sustaining valve type 03 (S)

Pressure sustaining/relief valves opens when the presetinlet pressure is achieved.

The standard pressure range is: 3 - 21 barOn request: 0,1- 6 bar

Float valve type 04 (N)

Float valve used to maintain a constant level. The controlvalve is installed in the water tank on site and connectedto the main valve by a pipeline. Opening and closingspeeds can be adjusted. (The DN10 pipeline installedbetween the main valve and control unit is not includedin the scope of supply.)

Float valve type 04 (DI)

Float valve with adjustable minimum/maximum level. The main valve opens when the minimum level isreached and closes when the maximum level is reached.The difference between the minimum and maximum levelcorresponds to the length of the pipeline between thetwo floats. Adjustable opening and closing speed. (Thepipeline installed between the main valve and control unit is not included in the scope of supply.)

Level control valve type 05 (A)

Control valve used to maintain a constant (adjustable)water level. If the water is drained from the reservoir, thepressure in the diaphragm chamber is lowered and themain valve opens.

Standard range: 0.5 - 6 mWsUpon request. 4 - 21 mWs

Adjustable opening and closing speed. (Pipeline frommain valve to reservoir needs to be installed on site.)

Flow control valve type 06 (OC)

Flow control valve used to limit the flow to an adjustablemaximum irrespective of the inlet pressure.

Level Control

Flow Control

Specifications

Differential pressure:Minimum differential pressure:

0.5 bar (lower differential pressure upon request)Maximum differential pressure:

according to cavitation diagram

Application areas and limits

Flow velocity:Maximum flow velocity in continuous operation:

4,5 m/sMaximum flow velocity for short-time operation:

5,6 m/sRecommended flow velocity

2-3 m/s

Cavitation curve when the valve is open

A: No cavitation:The standard valve can be used.

B: Cavitation area:IIn this area two serially mounted valves are to be used or a valve with a special orifice cylinder. Please consult the manufacturer on this issue

C: Transitional area:Please contact the manufacturer for information about this area.

Nominal diameter 50 65 80 100 125 150 200 250 300 400

Q-min 0,7 0,8 1,6 2,7 4,4 5,3 13,5 25 41 110

Q-maxContinuous operation

32 54 82 127 199 286 509 800 1150 2450

Q-maxShort-time operation

40 68 103 159 249 358 636 1000 1438 3070

Flow characteristics [m³/h]:

If in the application of a pressure reducing valve, volumes are to be below the minimum volumes, a bypass with an additionalpilot valve is to be used.

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0 1 2 3 4 5 6 7 8Downstream pressure [bar]

252423222120191817161514131211109876543210

Up

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VAG PICO® Diaphragm Valve

Installation recommendations

The automatic control valves should be installed between twoshut-off valves and strainer in a horizontal pipeline.

A bypass allows the maintenance of the control valve duringoperation. For the protection of the supply network, werecommend the installation of safety valves.

Main line(Basic components)

VAG PICO Diaphragm Valve

VAG Strainer

VAG DUOJET® Air Valve

VAG EKOplus® Gate Valve

VAG FLEXINOX® (Dismantling Piece)

Discharge / safety valve

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Bypass line(horizontal in general and at the same level as the main line)

VAG PICO Diaphragm Valve

VAG Strainer

VAG FLEXINOX® (Dismantling Piece)

VAG EKOplus® Gate Valve

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VAG-Armaturen GmbHCarl-Reuther-Str. 168305 MannheimGermanyPhone +49 6 21 749-0Fax +49 6 21 749-2153info@vag-armaturen.comwww.vag-armaturen.com