641/01 AVK SWING CHECK VALVE OPERATION & MAINTENANCE MANUAL. AVK UK Limited OM270710

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1 AVK SWING CHECK VALVE 641/01 OPERATION & MAINTENANCE MANUAL The designs, materials and specifications shown are subject to change without notice due to our continuing programme of product development. AVK UK Limited OM270710

2 1 INTRODUCTION This manual has been prepared to assist you safely install, operate and maintain the Glenfield Swing check valves covered by this manual, giving long and reliable service, and maintaining their maximum efficiency. For ease of reference, it has been divided into sections covering all aspects of use, and it is in the users best interests to read it and ensure that it is fully understood. HEALTH AND SAFETY AT WORK Please ensure that all relevant Health and Safety issues and regulations are strictly adhered to, prior to and during any installation or maintenance work carried out on these valves. It is essential that wherever work is being undertaken on a valve that may involve the release of any internal pressure, the valve is fully depressurised prior to any work being carried out, and the line drained. It is also essential that the user handling the valve is aware of the weight of the components or assemblies to be handled and manipulated during installation and maintenance. It is the end users responsibility to ensure that safe working practices are followed at all times. Whenever Glenfield Valves products are installed, operated, or maintained, the inherent dangers of pressurised liquids and gasses, which can be severe, must be addressed. Therefore, it is essential that staff undertaking these operations are adequately trained and it is the responsibility of the end user to ensure that only trained and competent staff undertake these duties. This manual has been designed to assist, but it can never fully replace quality training in the workplace. However Glenfield Valves technical staff are always available to answer any questions relating to specific problems that may not be covered by this manual. Glenfield Valves products are designed and manufactured to be fit for purpose, and to a high and reliable standard. This provides a safe product with minimum risk to health when used correctly for the purpose for which it was designed. However, this assumes that the equipment is used and maintained in accordance with this manual, and the user is advised to study this manual, and to make it available to all staff that may need to refer to it. Glenfield Valves cannot be held responsible for any incidents arising from incorrect installation, operation or maintenance. The responsibility for this must rest wholly with the end user. Note: These valves are NOT designed for end off line ' services. In the event of a valve being mounted on the end of a pipeline, we strongly advise the use of a blanking flange or plug. Ensure that the main will NOT be re-charged before all on the valve is completed.

3 2 SPARE PARTS The use of inferior materials or parts in a valve can have serious consequences. Therefore it is absolutely essential that in order to guarantee the highest level of safety and performance, only genuine Glenfield Valves spare parts are be used. Glenfield Valves cannot accept any responsibility whatsoever for the fitting and subsequent failure of any non-glenfield Valves or non-approved parts. GENERAL Glenfield Valves Swing Check Valves are primarily designed and manufactured for the prevention of flow reversal and are suitable for potable water or sewage applications. The operation of the valve is fully automatic allowing liquid to flow in one direction only. The function of the external lever and weight, where fitted, is to provide additional weight loading to the valve disk, thus giving mechanical assistance towards closure. The position of the weight is adjustable and allows the closure rate to be varied to suit the actual working conditions. The function of the proximity switch where fitted, is to indicate the position of the valve door i.e. closed or open. The switch is set to operate when there is a flow through the valve and the door is in the open position. Swing check valve options covered by this manual Standard (without lever and weight) Lever and weight (right hand as standard) Lever, weight and guard Lever, weight, guard and proximity switch DESIGN CONSTRAINTS Please consider the following points when selecting your valve: Consideration should be given at the design stage where valves will be located to give access for operation, adjustment, maintenance and repair. If a valve is installed less than 6 diameters downstream of an elbow or tee etc., it will experience very high-localised velocities that are far in excess of the average velocity. This high velocity will result in excessive turbulence within the valve and variations in performance may be experienced, therefore installation in this area should be avoided. Valves must be provided with adequate support. Adjoining pipework must be supported to avoid the imposition of pipeline strains on the body which may impair its performance Heavy Valves may need independent support or anchorage.

4 3 STORAGE AND HANDLING Storage If valves are to be stored in the open for some time, protection should be provided to keep the valves clear of sand and mud Protection against weather should be provided. Ideally, valves should be kept indoors, with the actual valve temperature always higher than the dew point. If outdoor storage is unavoidable, valves should be supported off the ground and protected by a weather proof cover Valves may be stacked and the upper open end covered with waterproof material and boarded over Handling When handling valves, it is preferable to lift by means of shackles in the holes provided in the valve body/cover Where slings are employed the valves should only slung by the main body casting only. No contact should be made with the lever or guard where fitted. Valves should be lowered gently onto wooden battens placed on firm ground, clear of mud and water

5 4 INSTALLATION & COMMISSIONING It is essential that the end user of the valve is aware of the weight of the components and / or assemblies that must be handled and manipulated during installation and maintenance. It is the end users responsibility to ensure that safe working practices are followed at all times. Before installing the valve into the pipeline Only suitably qualified and experienced engineers should install valves. All packing material must be removed Valve Installation, as cast on the body, should correspond with the direction of flow in the pipeline Lifting lugs, plates or eye nuts should be used to lift the valve Immediately prior to valve installation, the pipework to which the valve is to be located should be checked for cleanliness and freedom from debris. As far as is practicable, inspect the valve interior through the end ports to determine whether it is reasonably clean and free from foreign matter. Check the mating flange facings (both valve and pipework flanges) for correct gasket contact face, surface finish and condition. If a condition is found which might cause leakage, do not attempt to assemble until the condition has been corrected. Bolting up and tightening of joints should be done in a systematic manner to avoid undue stress in the body valve Ensure that the main is clean and the valve has not closed on any debris. Should limit or proximity switches be fitted, it may be necessary to adjust their position during commissioning. GENERAL MAINTENANCE INSTRUCTIONS All Glenfield Swing Check Valves are automatic in operation allowing flow in one direction only. MAINTENANCE The valve is designed for underground use in mind with little maintenance and no lubrication required. However, attention to the following points will ensure satisfactory working at all times. Removing the cover form the valve and examining the faces and moving parts for wear and if necessary, removing the spindle or shaft, and lifting out the internals for more detailed examination or re-conditioning. New parts can be fitted as required. The frequency of the maintenance depends not on the length of time that the valve has been installed, but on the flow conditions. If the flow is such that the door is held stationary against the open stop, the valve should operate for some years without attention. However, fluctuating flow or low flow causing constant movement of the door and linkage, can result in spindle wear. The need for servicing due to wear and tear is indicated by mechanical noise and/or failure of the valve to prevent backflow. It is usually advisable to renew joints after disturbing them.

6 5 Maintenance schedule 1. Valves that are not operated frequently and which may remain open or closed for long periods should be operated, even partially, about once a month. 2. Inspection Should be carried out thoroughly every six months. 3. Gaskets When faulty gaskets are the cause of leaks, care should be taken to ensure that the replacements are of the correct material. If the cover is removed a new gasket should be fitted before replacing. 4. Vibration After lengthy periods of operation connecting bolts should be checked for tightness. (This should be done more often if vibration is experienced in the pipeline). 5. Freezing Where it is necessary to keep a valve closed in cold weather precautions must be taken to prevent it 'freezing up'. 6. Scouring Routine scouring is of great value in keeping the water free of grit and thus saving unnecessary wear and tear on the faces and seals. instructions Lever, Weight and Guard removal (where fitted) Remove bolts from the guard cover and remove Detach the lever and weight from the spindle by removing the securing bolt located on the level boss. Great care must be taken and the correct handling equipment used when removing the lever and weight due to the weights involved. Remove the lever from the spindle. Mark/note the position of the cam (where fitted), in relation to the proximity switch, to aid refitting. Remove cam by unscrewing the grub screw attaching it to the spindle Remove proximity switch (where fitted) as described in the relevant section later in this manual Remove bolts attaching the guard to the body and remove Assembly is the reverse of the above procedure. With special attention given to the positioning of the cam in relation to the proximity switch

7 6 GLAND PACKING REPLACEMENT End bearings or glands in conjunction with gaskets and or packing are used to prevent water leaking from the valve via the spindle. There are various methods for re-packing the glands depending on the size of the valve and which one or if both are leaking. Some methods will require the spindle to be supported in some way to maintain the shaft alignment. See table below. In the event of leakage from the gland/spindle area or where damage to the door or spindle is suspected the recommended procedures are as follows: Isolate the valve requiring servicing and drain the line Identify the type of spindle sealing method used from the general arrangement drawing of the valve in question. Typical Spindle Sealing Method Guide Valve Size (DN) Standard Door/spindle Extended Spindle Sealing Method Spindle Support 350 & 400mm End bearings (2) Gaskets Yes " " End bearing (1) & Gland bearing (1) Gaskets & 'O' Ring(s) Yes mm End bearings (2) Gaskets Yes " " Gland (1) & Gland/stuffing box (1) Gaskets & Packing Yes 700mm & above Glands (2) Packing No " " Gland (1) & Gland/stuffing box (1) Gaskets & Packing No Remove guard (where fitted) if necessary for access Leaks from the gland (DN450mm >) Where gland packing is used, usually the lever/drive end, tighten the gland flange slightly and evenly until the leak ceases If the leak is still present then additional packing can be added or if the leak is persistent then the gland will require re-packing. Adding Additional Packing Additional packing can be added by loosening the nuts of the gland just sufficiently to insert additional packing. Re-tighten the gland flange nuts evenly until the leak ceases. Warning: DO NOT remove the gland fully as this may result in the valve spindle moving out of alignment in some types of valve

8 7 Gland Re-packing (lever/drive end of spindle) (DN450mm >) Isolate the valve requiring servicing and drain the line Remove valve cover Support the door by use supporting/slinging the spindle from a rigid structure i.e. lifting frame, crane etc. and/or by packing/wedges placed at the bottom of the door. Remove the nuts holding the gland flange in place and withdraw the gland. Replace the old packing with new packing and refit gland to spindle Tighten the gland flange nuts sufficiently to support the weight of the spindle - but do not over tighten Remove wedge/packing from the bottom of the door and refit the cover Refill the line and test for leakage. The gland will require to be adjusted to stem any leakage by evenly tightening the gland flange until the leak ceases. End Bearing/Gland Gasket Replacement (DN mm) Remove cover Ensure that the valve door is in the closed position Support the door by use supporting/slinging the spindle from a rigid structure i.e. lifting frame, crane etc. and/or by packing/wedges placed at the bottom of the door. Remove the nuts holding the end bearings/gland flange to the body Remove the end bearings/gland flange and replace the gasket Re-assembly is the reverse of the above procedure Door and Spindle Replacement Isolate the valve requiring servicing and drain the line Ensure that the valve door is in the closed position Remove cover Remove lever, weight, guard and proximity switch (where fitted) Support the door securely in position by packing/wedging the bottom of the door. Remove retaining pin(s) or bolt/screw/key holding the lever arm to the spindle DN350 & 400mm retaining pin(s) DN mm retaining pins(s) or grub screw and key DN700mm & above Hex nut and key

9 68 Remove the end bearings/gland and packing from both ends of the spindle. Withdraw the spindle from the valve taking care to remove any collars present as the they become loose as they are released from the spindle. The door along with the lifting lever (where fitted) can now be removed through the cover opening for servicing, taking care not to damage the seat or face rings. The lever arm being detached from the by removing the bolts holding the lifter plate to the door. Re-assembly is the reverse of the above procedure Proximity Switch Fitting Instructions General Proximity switches fitted to swing check valves are used to indicate the position of the valve door and if the flow through the pipeline has been reversed. The proximity switches are set at the factory during our works test and should not require any adjustments. However, if there is a requirement for the switch to be removed then the following instructions must be followed: Removal Ensure the valve is isolated and the door is in the closed position Remove guard cover from the valve Measure and note the distance from the sensor face of the switch to the cam lever Remove the locking nut, which secures the switch to the inside of the guard. Try not to disturb the position of the other nut on the outside of the guard, as its position will provide a guide for the required gap during the re-fitting of the switch Remove the switch from the guard Fitting Re-fit the switch in its locating hole and secure with the retaining nut Adjust the gap between the sensor face of the switch and the cam lever using the switch mounting nuts, until the required gap is achieved. Tighten switch-mounting nuts To ensure that the switch is operating correctly, test the switch by lifting the lever, which should activate the LED as the cam lever moves out of switches sensing distance. When the door is closed the switch is in the off position and the LED extinguished Note: To prevent injury, always use the correct lifting procedures and never exceed your comfortable lifting limit. Great care should be taken when lifting the lever and weight due to the combined weights (including the door) of the components involved. This is especially relevant on the larger sizes of valves where the lever and weight should only be lifted by mechanical means

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13 68610 AVK UK Limited Northampton Office 8 Rushmills, Northampton, NN4 7YB England, UK. Tel.: +44 (0) Fax.: +44 (0) Chesterfield Office Colliery Close, Ireland Ind. Est., Staveley, Chesterfield, S43 3FH, England, UK. Tel.: +44 (0) Fax.: +44 (0) AVK UK Limited