The Axial Flow Valve. Class 300/ SERIES

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1 The Axial Flow Valve SERIES Class 300/600

2 THE AXIAL FLOW VALVE - SERIES 300/600 A UNIQUE REGULATOR What is the Axial Flow Valve? The Axial Flow Valve is a regulating device used to control gas pressure in natural gas transmission and distribution applications worldwide. The Axial Flow Valve is the principle regulator used in most of Elster instromet's Pressure Reduction Stations. The Axial Flow Valve (AFV) has a number of key advantages over similar regulators. It is very compact Greater capacity 'size for size' compared with similar regulators It is very simple in construction and operation Simplicity - reliable and easy to maintain It has a wide range of application using one common design A proven, low risk design which has been in the market for over 30 years The Axial Flow Valve is an industry standard for pressure regulation in distribution and transmission applications. Elster Instromet offer a full range of Axial Flow Valve regulators to cover mbar to Class 600 applications and sizes from 50mm to 300mm. The regulator is pilot controlled and Elster Instromet can provide a full range of supporting controls. Introducing the 'Quiet' Axial Flow Valve (QAFV) The generation of noise during the pressure reduction process can cause problems in sensitive locations. Noise reduction is an increasingly important environmental, social and personnel safety issue. In response to these demands, Elster Instromet has enhanced its range of Axial Flow Valve regulators by incorporating an integral silencer. The novel metal foam insert reduces noise significantly and can eliminate the need for expensive traditional noise reduction measures such as cladding or acoustic enclosures. Based on extensive research and development, Elster Instromet can provide noise prediction calculations specific to your application and operating conditions. The silencing element fits within the body of the Axial Flow Valve and its simplicity and form is unchanged, making it ideal for retrofit applications. Maintenance intervals are unaltered. Elster Instromet can supply fully assembled Quiet Axial Flow Valves, or a silencing kit enabling existing installations to be upgraded.

3 00 regulators. This can be reduced further by fitting THE AXIAL FLOW VALVE - SERIES 300/600 BENEFITS REDUCED COSTS * Greater capacity Compared with similar regulators, the Axial Flow Valve offers greater capacity 'size-for-size'. * Extended service life Long life components and unique 'reversible' sleeve extends service life. * Lower noise The design of the Axial Flow Valve means that it is quieter 'size-for-size' compared with other the quiet trim to the Axial Flow Valve (QAFV). * Common training The common design for all sizes means common training and procedures for operational and maintenance staff. * Lightweight and compact The compact size of the Axial means that the overall size and footprint of a Pressure Reduction Module can be reduced. Back to back installation or with porting ring considerably reduces overall station dimensions. This in turn means smaller kiosk/land requirements. INTERCHANGEABLE VALVE CAGE CLOSURE VALVE BODY VALVE CAGE CLOSURE RUBBER SLEEVE SINGLE WORKING PART QUIET TRIM BOLT WASHER O-RING FAIRING NUT RELIABLE The Axial Flow Valve is renowned for reliability. Some of the design features that contribute to this are: * Only one moving part an expandable sleeve is the only moving part, eliminating friction and sliding wear * Stainless Steel Closure on the inlet and outlet, are hardened to resist abrasion and improve control. * Toroidal Sleeve Design ensures longer sleeve life, positive closure and smoother operation. SIMPLE * Only 4 components The unique axial concept consists of only four main components; A high integrity flexible membrane, inlet and outlet flow cages and a body. * One design concept covers all pressure ratings and sizes * Interchangeable components All components are fully interchangeable and reversible reducing the need for spares and extending operating life. * Compact and lightweight The Axial Flow Valve is the most compact and lightweight regulator in its class * One bolt construction The Axial Flow Valve construction means that no special tools or techniques are required to dismantle or re-assemble. * Wafer design The Axial Flow Valve design allows installation between flanges and compact back to back arrangements.

4 THE AXIAL FLOW VALVE - SERIES 300/600 BENEFITS VERSATILE The design of the Axial Flow Valve means that it can be used in a wide range of applications. A simple change of sleeve upgrades the axial flow valve from one pressure range to another. A change of control will convert the axial from pressure to volumetric control or to monitor override, or safety control. Conversion from pressure control to relief duty is also achieved in this way - without modification to the axial flow valve. Utilising the appropriate control system, the Axial Flow Valve can be used for: * Pressure reduction from 100 bar down to 30 mbar * Active or monitor mode * Two stage pressure cut * Volumetric flow control * Over and under pressure shut off * Back pressure/relief valve * Pulsation dampening * Remote control via pneumatic or electronic signal * Can be installed in any position * Low operating differential Easy to maintain The simplicity of the Axial Flow Valve makes maintenance easy. Whilst no special tools are strictly required, Elster instromet can provide a range of simple, effective tools to make maintenance even simpler. * Easy to Maintain Fully interchangeable and reversible components and the wafer design construction, ensure that the axial flow valve is simple to install, remove and maintain. * Minimal Spares With only two body ratings, and four models covering a range of pressures from 0.1 bar to 100 bar, spares are kept to a minimum. The only spares required for each size of valve are a sleeve and three 'O'-rings. * Extended Service Life The Axial Flow Valves unique 'reversible' sleeve extends service life * Maintenance Tools Elster Instromet can provide additional tools to make maintenance even simpler.

5 300/600

6 THE AXIAL FLOW VALVE - SERIES 300/600 MAINTENANCE AND ACCESSORIES Fairing nut socket A special socket for fairing nut removal is available from Elster Instromet. The simplicity of the Axial Flow Valve makes maintenance easy. Whilst no special tools are strictly required, Elster Instromet can provide a range of simple, effective tools to make maintenance even simpler. Despite claims that top entry regulators designs are easier to maintain the Axial remains the simplest device in its' class. Try comparing the removal and maintenance of a 300mm Axial Flow Valve with an equivalent sized top entry regulator; the added complexity of the top entry design together with more bolts to remove and heavy covers can make maintenance time consuming and difficult. Additionally, lifting equipment is still required for larger top entry regulators. 300/600 Lifting Eye One lifting eye fits all sizes, however only the two largest sizes generally require lifting equipment. Centering Tubes The Axial Flow Valve is a wafer design which simply bolts between flanges. To ensure exact centering of the valve for full capacity, centering tubes are easily fitted over the existing bolts. (Series 300 only). Flange Spreaders To make removal even easier, the axial flow valve can be supplied with simple flange spreaders.

7 300/600 Lifting davit and mounting post To assist with removal of the larger Axial Flow Valve sizes, Elster Instromet can supply a newly designed lifting davit. This meets all recent approvals and may be supplied as an option on new build stations or fitted to an existing skid by adding the mounting post. The lifting davit is also used with the Elster Series 10 Orpheus, reducing cost and enabling the davits to be used with a mix of station types both above and below ground. Support jig The Axial Flow Valve may be supported in a variety of ways whilst removing the centre bolt. Elster Instromet can provide a jig that supports the control gallery on the AFV and eases bolt removal. Other accessories... Flow Limiter Certain applications such as relief duty require that the maximum flow rate is limited. Elster Instromet can supply restrictors and limiters for regulator and relief applications. Pre-piped pilot loops Elster Instromet can design and supply complete, pre-piped pilot control loops including ancillary systems such as pressure profiling or clock pilots. Please contact us to discuss your requirements. Porting Rings When space is limited, Axial Flow Valves may be fitted back-to-back by use of a porting ring. This enables two stage configuration in a very compact area. Operating indicator An Elster Instromet Model 150 Differential Pressure Gauge can be fitted to indicate valve operation and opening.

8 THE AXIAL FLOW VALVE - SERIES 300/600 HOW IT WORKS The heart of the Axial Flow Valve TM is the unique 'V' form flexible sleeve. This is the only moving part. Throttling and control is performed by the sleeve expanding and contracting in relation to the inlet and outlet slotted cages which fit inside the sleeve and are formed to match the 'V; configuration. An outer cylindrical body surrounds the cage and sleeve assembly forming a 'V' shaped cavity all around the sleeve. All four parts are held together with a single bolt through the centre of the cages. Control is achieved by modulating the pressure in the cavity at the back of the sleeve. View 1 With gas supply pressure at the back of the sleeve equal to inlet pressure, the sleeve is closed against the inlet cage. A closing force equal to inlet pressure acts on the downstream 'V' sleeve area forcing it against the downstream cage to give double closure and completely tight seal. View 2 Reducing the pressure at the back of the sleeve creates a pressure imbalance across the sleeve, inlet pressure now being higher. This expands the sleeve away from the cages thereby allowing flow from inlet to outlet. The pressure at the back of the sleeve can now be referred to as the 'Control' Pressure. View 3 Reducing the control pressure further increases the differential across the sleeve allowing it to expand further until the sleeve is flat against the body for 100% capacity. The position of the sleeve, and therefore flow, is controlled by the pressure at the back of the sleeve.

9 THE AXIAL FLOW VALVE - SERIES 300/600 CONTROL SYSTEMS CONTROL To control the pressure on the back of the sleeve, two control systems are available. Inspirator Control (Standard) INSPIRATOR CONTROL EXTERNAL SUPPLY (P1) FIXED INSPIRATOR For general transmission/ distribution, minimal pressure differential and enhanced control applications OPERATOR Operation As the operator opens, a flow and hence pressure drop is created across the inspirator. The inspirator boosts the pressure drop to the back of the axial sleeve by approximately 3:1. SUPPLY FILTER ` TO AXIAL SLEEVE ADJUSTABLE RESTRICTOR P1 P2 RESTRICTOR CONTROL Restrictor Control ADJUSTABLE RESTRICTOR For fast response and applications with minimal downstream volumes. Operation As the operator opens, a flow and hence pressure drop is created across the restrictor. This pressure drop is transferred directly to the back of the axial sleeve. P1 OPERATOR P2 SUPPLY FILTER INTERNAL SUPPLY (P1) TO AXIAL SLEEVE TO OPERATOR In practice there are many different control system configurations. Elster can supply the Axial Flow Valve as a component or with a pre-piped Pilot Control Loop. Please call Elster Instromet to discuss your application.

10 300/600 OPERATORS THE AXIAL FLOW VALVE - SERIES 300/600 CONTROL SYSTEMS There are many ways of operating the Axial Flow Valve, the simplest being the spring loaded pilot. This device simply monitors the condition to be controlled and opens or closes accordingly. The photo below shows a simple pressure controlling pilot, which is spring biased open. As the downstream pressure falls, the pilot opens and bleeds off control pressure downstream. A rise in downstream pressure causes the pilot to close thus increasing the control pressure to the back of the sleeve. Remote operation can be achieved in a variety of ways, using external electronic controllers and suitable I to P converters. Elster Instromet can also supply a motorised actuator for control of pilots.

11 THE AXIAL FLOW VALVE - SERIES 300/600 Technical Elster can provide a PC based design tool that makes sizing calculations quick, accurate and easy. In addition field or office based applications engineers are available to assist with design and selection. Please give us a call. Inlet pressure mbar bar Flow range Sm 3 /h Outlet pressure - 30 mbar - 50 bar Infinite turn down - Suitable for most gases - For very small capacities or relief applications, fitting an internal flow limiter can restrict the range of the Axial Flow Valve. Please call Elster Instromet for details. SERIES 300 Size DN50 DN80 DN100 DN150 DN200 DN300 Weight (kg) SERIES 600 Size DN50 DN80 DN100 DN150 DN200 DN300 Weight (kg) 4 NOT AVAILABLE NOT AVAILABLE ENVIRONMENTAL DATA Noise Noise prediction estimates can be provided for the axial flow valve and complete installation on request. These calculations are based upon a combination of empirical data using established Elster formulae for pressure regulator sizing. Extensive field tests have resulted in very significant improvements in terms of integrity, fluid dynamics and full bandwidth noise attenuation. Key benefits of the Quiet Axial Flow Valve include: Significant noise reduction achievable Integral silencer means simplicity and form of AFV unchanged Ideal for retrofit applications Maintenance intervals identical to standard AFV

12 For further information contact: ELSTER INSTROMET IS A WORLD CLASS SUPPLIER OF TOTAL GAS MEASUREMENT AND CONTROL SYSTEMS Further details on our full range available on request Elster Instromet Axial Flow Valves are CE marked and conform with the Pressure Equipment Directive and EN/334. All rights strictly reserved. No part of this document may be stored in any retrieval system, or any form or by any means without prior written permission from Elster Instromet Limited. Every effort has been taken to ensure the accuracy of this specification. However, Elster Instromet operate a continuous improvement policy and we are continually improving our products and systems which could, without notice, result in amendments or omissions to this specification. We cannot accept responsibility for damage, injury, loss or expenses resulting therefrom. Please contact Elster Instromet for latest product information. Elster Metering Ltd 4 Pate Road, Melton Mowbray, Leicestershire LE13 0RG Main: Tel: +44 (0) Fax: +44 (0) sales@elster-instromet.co.uk Part No D /03