Dewrance Check Valves, High Pressure
Contents
1. WARNING Ensure that there is no pressure in the pipeline or valve The pipeline should be drained prior to dismantling the valve 1 Fully retract the regulating nut on the filter regulator to zero pressure 2 De energize the solenoid to exhaust the air in the pneumatic cylinder A 3 Isolate the compressed air and electrical supplies 4 Label and record cables before disconnecting electrical connections to solenoid valves and limit switches FIGURE 3 Cover 3 Stem guide 160 5 Disconnect compressed air connection 6 Loosen gland nuts 78a then utilizing the eyebolt in the top of the actuator A and suitable lifting equipment support the weight of the actuator Unscrew and remove the lower actuator nuts that secure the actuator to the adaptor plate 88 Carefully raise the actuator to the half way position Slacken set screw 200b Utilizing the hole in stem 4 and the flat portion on the piston rod unscrew stem 4 from the actuator piston rod and remove stem indicator 39 Protect actuator from ingress of foreign matter See Appendix 1 for actuator maintenance instruction 7 Screw three suitable eyebolts into the hreaded holes on the side of the cover 3 Thread size is stamped adjacent to the holes 8 Unscrew all cover nuts 78 9 Utilizing the eyebolts and suitable lifting equipment lift off the cover assembly 10 Remove gland nuts 78a 11 Remove gland 5 gland flang2. 3 5 to 6 turns 2 Loosen nuts 2 and 4 5 to 6 turns 3 Repeat steps 1 and 2 until compression spring reaches its free length Tightening of tie rod nuts Tightening of nuts is the reverse procedure of removal FIGURE 6 WARNING the tie rod fixings on the back face of the cylinder are welded solid no attempt should be made to dismantle the cylinder from this end as this will result in the uncontrolled release of the compression spring 6 Remove the tie rod nuts and lift the back cover and tie rods clear Remove the compression springs and preserve 7 Remove tube from front end cover if necessary by holding tube do not clamp and lightly tapping on the four corners of the front cover with a fiber mallet until the tube is clear of the front spigot 0 ring Preserve 8 Wipe the piston rod clean Remove the piston rod and piston assembly from the front end cover bush Take particular care not to damage seats or bearings when passing rod end through bush Preserve 9 Grip the piston and rod assembly as indicated Figure 7 and tap out the locking roll pin with a 5mm diameter punch Preserve roll pin Loosen piston rod using spanner flats Refer to page 38 for spanner sizes No marking or gripping should be made on the shaft O D Undo the remaining thread engagement by hand supporting both piston rod and piston Preserve 10 Place front end cover on bench with bush fixing screws facing uppermos
3. 8 Refit F R L Filter Regulator Lubricator and junction box mounting plates Clean and reconnect the air supply pipe nut to elbow fitting ensuring an airtight joint refit solenoid cab to solenoid valve 9 Refit cylinder assembly to rig making any trimming adjustments as required D Recommended grease and lubricant Grease rocol MTS2000 or equivalent Air line lubricant Shell Tellus 37 or equivalent E Wrench sizes Piston rods 320 mm bore cylinders 42 mm A F 250 mm bore cylinders 36 mm A F 200 mm bore cylinders 36 mm A F Tie rod nuts 320 mm bore cylinders 36 mm A F 250 mm bore cylinders 30 mm A F 200 mm bore cylinders 38 mm A F SEMPELL DEWRANCE BLEED STEAM CHECK VALVES INSTALLATION AND MAINTENANCE INSTRUCTIONS APPENDIX 2 400 425 450 class body 200 250 300 350 400 425 and 450 class disk Product Torque lb ft Torque Nm Torque wrench values side flange nuts 78b B43EN200QFDN 25 34 B31EV400RFDC 46 62 Torque wrench values cover nuts 78 B43EN200QFDN 219 297 B31EV400RFDC 424 57 5 gt PENTAIR PENTAIR VALVES amp CONTROLS www pentair com valves All Pentair trademarks and logos are owned by Pentair plc All other brand or product names are trademarks or registered marks of their respective owners Because we are continuously improving our products and services Pentair reserves the right to change product designs and specifications without notice Pentair is an equal opportun
4. A Radial clearance cold Max 0 35 mm Min 0 18 mm t Assembly check Clearance gap between bushes 96 and 99 with dick in shut position to be 0 6 to 1 0 mm PARTS LIST REFERRING TO FIGURES 1 AND 2 Ref no No off Description Ref no No off Description 1 1 Body 78 ii Cover nut 3 1 Cover 78a 4 Gland nut 4 l Stem 78b 8 Side flange nut 5 1 Gland 80 1 Neck bush 17 1 Cover gasket 80a 1 Guide bush 17a 2 Side flange gasket 88 1 Adaptor plate 24 2 Side flange 96 2 Hinge pin bush 28 m Cover stud 99 2 Hinge pin housing 28a 4 Gland stud 160 Stem guide 28b 8 Side flange stud 160a Limit switch striker plate 39 1 Stem indicator 200 4 Cap head screw 48 4 Pillar 200a 4 Safety washer 51 1 Disk 200b Set screw 58 1 Hinge pin A Pneumatic actuator 68 ie Gland packing B 2 Limit switch Quote product number for quantity SEMPELL DEWRANCE BLEED STEAM CHECK VALVES INSTALLATION AND MAINTENANCE INSTRUCTIONS 5 COMMISSIONING A Connecting to electrical supply For single acting pneumatic actuator with solenoid valve wired for normally closed positions 1 Ensure that the adjusting nut on the filter regulator is fully out anti clockwise then turn on the air supply to the inlet supply of the filter regulator 2 Connect the electrical supply to the solenoid valve 3 Energize the solenoid valve 4 Screw in the adjusting nut on the filter regulator clockwise until the working pressure is obtained
5. consequences of each way Consequently Dewrance has not undertaken any such broad evaluation and thus who uses a procedure and or tool which is not recommended by Dewrance or deviates from Dewrance recommendations must be thoroughly satisfied that neither personal safety nor valve safety will be jeopardised by the method and or tools selected If not so satisfied contact Dewrance if there are any questions relative to tools methods Some of the products manufactured by Dewrance may be used in radioactive environments Consequently prior to starting any operation in a radioactive environment the proper health physics procedures should be consulted and followed if applicable The installation operation and maintenance of valves and or valve products may involve proximity to fluids at extremely high pressure and or temperature Consequently every precaution should be taken to prevent injury to personnel during the performance of any procedure These precautions should consist of but not limited to ear drum protection eye protection and the use of protective clothing i e gloves etc when personnel are in or around a valve work area Due to the various circumstances and conditions in which these operations may be performed on Dewrance products and the possible hazardous consequences of each way Dewrance can not possibly evaluate all conditions that might injure personnel or equipment Nevertheless Dewrance does
6. edge with port uppermost Do not place front cover front face down on the bush head as this will cause distortion to the lip seal Wipe clean and air blast the spigot O ring groove spigot diameter and inside face of the front cover Wipe O ring clean and refit in spigot groove Air blast port Cover in clean cloth and preserve Piston rod assembly wipe out center bore of piston and blast clean Clean piston rod O ring and refit in bore Figure 9 of piston Wipe the piston rod clean insert threaded end of piston rod into bore of piston passing it through piston rod 0 ring until solid Refit piston tail rod and tighten hand tight Grip piston rod assembly by Tail rod in a vice Figure 2 and tighten rod assembly using spanner flats see Paragraph E for wrench sizes until the lockpin hole in the tail rod and threaded part of the piston rod are in line Tap the lock rollpin in such that it is located midway through the tail rod using 5 mm dia punch Clean cut U ring groove and piston tape groove air blast Clean U ring and piston tape refit Preserve assembly Front cover and piston rod assembly support front end cover on one edge on a bench Remove cloth bungs from bush and air blast bore Wipe the piston rod clean and lightly grease the full length and diameter see Paragraph D for grease type Offer the piston rod end up to the back face of the bush carefully passing the rod end through t
7. gt PENTAIR SEMPELL DEWRANCE BLEED STEAM CHECK VALVES INSTALLATION AND MAINTENANCE INSTRUCTIONS Before installation these instructions must be fully read and understood GENERAL e This covers bled steam check valves fitted with pneumatic actuator and external limit switches e For spare parts refer to sheet giving details of classification When ordering spare parts quote full product number stamped on nameplate e Refer to Appendix 2 for specific product numbers 1 SAFETY NOTICE Proper installation operation and maintenance are essential to the safe and reliable operation of all valve products The relevant procedures recommended by Dewrance and described in this manual are effective methods of performing the required tasks Some of these procedures require the use of tools specifically designed for an intended purpose These special tools should be used when and as recommended It is important to note that this manual contains various safety messages which should be carefully read in order to minimize the risk of personal injury or the possibility that improper procedures will be followed which may damage the involved Dewrance product or render it unsafe It is also important to understand that these safety messages are not exhaustive Dewrance cannot possibly know evaluate and advise any customer of all the conceivable ways in which tasks might be performed or of the possible hazardous
8. is an 3 Ensure gasket faces on body 1 and hinge important factor in obtaining a long term pin housing 99 are clean fit new side ight joint It is essential that the gasket flange gasket 17a slide in hinge pin be pulled down evenly Use feeler gauges housing 99 between the cover 3 and body 1 flange 4 Fit side flange 24 over side flange o ensure this compression is even studs 28a Caution do not lubricate gasket or gasket 5 Screw on side flange nuts 78b and tighten sealing faces Cover nuts 78 must be in a diametrically opposing sequence to a ightened in a diametrically opposing torque value shown in Appendix 2 sequence in a minimum of 3 stages to a 6 Using feeler gauges check that the orque value shown in Appendix 2 minimum clearance gap between hinge 13 Using lifting equipment as previously pin bush 96 and hinge pin housing 99 is described lift up actuator A and lower 0 6 mm to 1 mm 0 024 to 0 040 The valve over valve ensuring that actuator screwed is designed to these tolerances In the event ie rods locate into adaptor plate 88 of tolerances being outside the above limits Lower to half way position then fit position proceed as follows indicator 39 over stem 4 and screw Remove the hinge pin housing 99 on the stem into actuator piston rod secure affected side s referring to diagram below with pin 200b remove by grinding sufficient metal from Lower actuator all the way down onto ace shown to ac
9. offer the safety precautions listed on page 5 for customer information only It is the responsibility of the purchaser or user of Dewrance valves equipment to adequately train all personnel who will be working with the involved valves equipment Further prior to working with the involved valves equipment personnel who are to perform such work should become thoroughly familiar with the contents of this manual Accordingly should any additional copies of this manual be required they can be purchased by contacting Dewrance Nr D129 www pentair com valves 2012 Pentair plc All Rights Reserved VCIOM 01422 EN 15 05 SEMPELL DEWRANCE BLEED STEAM CHECK VALVES INSTALLATION AND MAINTENANCE INSTRUCTIONS 2 SAFETY PRECAUTIONS 4 DESIGN FEATURES AND NOMENCLATURE e Do not attempt to remove the packing gland nuts while valve is under pressure e Do not attempt to eliminate cover seal leakage by tightening the cover nuts while the valve is under pressure e The cover should never be removed while the valve is under pressure e Do not attempt to remove the Actuator while the valve is under pressure e No alteration and or modification should be made to any Dewrance valve except as sanctioned and or authorized by Dewrance e Never install or attempt to use any valve that is not properly identified as to its material and pressure class 3 INTRODUCTION Dewrance bled steam check valves are built to hig
10. response 5 Local on load testing can be achieved by operating the push button on the solenoid valve When the actuator is fully outstroked release the push button and the pneumatic actuator will return to the fully instroked position 6 After satisfactory completion of the above steps fully screw out anti clockwise the adjusting nut on the filter regulator and de energize the solenoid valve The stem 4 will move to the fully outstroked position When the valve is required to be put into service screw in clockwise the adjusting nut on the filter regulator until the working air pressure is obtained The stem 4 will move to the fully instroked position when the valve is ready for service 6 STORAGE Indoor storage of valves is recommended If prolonged storage is anticipated the valves should be stored in humidity controlled storage areas If valves are ordered to a more stringent cleaning and storage procedure the recommendations in that procedure should be followed 7 INSTALLATION AND WELDING When valves are received an enclosed Packing Note will provide an itemised statement of all valves and parts included in the shipment The recipient should check and account for each item on the list and then keep this packing note as a permanent record for these valves parts Unloading the valves should be done with care Remember that although the valve is a rugged piece of equipment it may still be d
11. Ill 95 Class Il Ill and IV 99 4 Consult recommended spare parts list by valve type to determine quantity of parts valves to be covered by the inventory plan 5 Select parts and specify quantities Identification and ordering essentials When ordering service parts please furnish the following information to ensure receiving the correct replacement parts Identify valve by Specify parts required by 1 Full product no 1 Part name 2 Size 2 Part number if known 3 Type 3 Quantity 4 Pressure temperature class 5 Tag number Item N Description 17 Cover gasket 17a Side flange gasket 68 Gland packing 4 Stem Gland 51 Disk 80 Neck bush 80a Guide bush 24 Side flange 30 Gland flange 39 Stem indicator 48 Pillar 58 Hinge pin 88 Adaptor plate 96 Hinge pin bush 99 Hinge pin housing 28 Cover stud 28a Gland stud 28b Side flange stud 78 Cover nut 78a Gland nut 78b Side flange nut Balance SEMPELL DEWRANCE BLEED STEAM CHECK VALVES INSTALLATION AND MAINTENANCE INSTRUCTIONS 11 VALVE REPAIR A Factory refurbishment Many customers find it desirable to return their valves to Dewrance for restoration or modernising Products returned to Dewrance valve repair center are restored to original specifications and returned with a new valve warranty B Service warranty Factory repaired valves carry a warranty that covers workmanship and new parts installed during repair for a period of one year fr
12. Refer to certified General Arrangement drawing for details of air pressure requirements The valve stem 4 will go to the fully instroked position 5 To ensure correct and safe operation check the outstroke by de energizing the solenoid valve As the air pressure is relieved the stem 4 will move to the fully outstroked position WARNING Care must be taken when exhausting the solenoid valve that the area close to the valve is kept clear Do not attempt to obstruct exhausting orifices by hand B Solenoid valve check Next it is necessary to check the functional operation of the solenoid to ensure that it responds correctly via the control system 1 With solenoid valve energized the stem 4 and the indicator plate 39 will move to a fully instroked position This will indicate the correct operation of the solenoid Open limit switch operation can also be checked at this stage 2 Select the close valve position via the control system for on load testing i e solenoid de energized and check the actuator has moved to the fully outstroked position Closed limit switch operation can also be checked at this stage 3 Select the open valve position via the control system for on load testing and check that the actuator has moved to the fully instroked position 4 With the working air pressure still set a simulated turbine trip should now be carried out via the control system to ensure the correct solenoid
13. amaged by abusive handling Skidded or chocked valves should not be unskidded until immediately before installation Improper installation of a valve can have very serious consequences resulting in a possible malfunction which may result in extensive and costly repairs Compliance with the following recommendations will do much to assure optimum performance of the valve after installation It is essential that precautions be taken to prohibit the entry of foreign debris inside the valve which could damage the seating surfaces before and or after installation SEMPELL DEWRANCE BLEED STEAM CHECK VALVES INSTALLATION AND MAINTENANCE INSTRUCTIONS Caution Provisions should be made for supporting the valve and adjacent piping so that the pipeline stresses will not be transmitted to the valve body during site welding of the pipe to the valve Welding and stress relieving procedures should conform to the applicable code or standard Weld with care and beware of weld splatter damaging internal parts Cleaning of pipelines in which the valve is installed and all connecting lines is essential before the unit is put into operation Welding beads scale and foreign debris in the line can cause damage to the valve seats and can result in leakage When raising pressure at any time in the pipeline system the valve gland nuts should be tightened or followed up at regular intervals 8 DISASSEMBLY REFER TO FIGURES 1 AND 2
14. e 30 and gland packing 68 12 Refer to the diagram below Check guide bush 80a for wear or scoring Should a new bush be required then first remove the old bush Do this by knocking back the places where the stem guide has been peened over the bush and then knocking guide out with suitable punch Guide bush 80a Peened over to retain guide bush as shown SEMPELL DEWRANCE BLEED STEAM CHECK VALVES INSTALLATION AND MAINTENANCE INSTRUCTIONS 13 Ensure that the disk 51 is in the closed position 14 Referring to Figure 2 check and record the gap between hinge pin bush 96 and hinge pin housing 99 15 Remove indicator locking nut 78 and indicator bracket 160 Refer to Figure 1 Appendix 1 16 Unscrew and remove side flange nuts 78b 17 Remove side flange 24 18 Remove hinge pin housing 99 A tapped hole is provided in the end of the housing o facilitate the removal 19 Withdraw the hinge pin 58 A tapped hole is provided in both ends of the hinge pin to acilitate the removal This tapped hole is he same size as the one in the hinge pin housing 99 20 To remove the disk 51 place a nylon sling hrough to hinge pin bush holes 96 in lugs on the disk then using lifting equipment hoist out the disk CAUTION When lifting out the disk 51 the tendency is for the disk to swing away from the body seat Care must be taken not to damage the body and disk seating faces when
15. g guidelines be utilized to establish meaningful inventory levels 1 Identify the total number of valves in service by size type number pressure temperature class and tag number 2 Identify the frequency of replacement tendency of specific parts Class Parts most frequently replaced Class II Parts less frequently replaced but critical in the event of an emergency requirement Class II Parts seldom replaced Class IV Hardware e g nuts bolts pins etc Class V Parts practically never requiring replacement 3 Need probability coverage is defined as the probable percent of total uninterrupted operational time which can be expected by stocking predetermined valve component classifications CLASSIFICATION OF SPARE PARTS Classification Class Parts most frequently replaced Class II Parts less frequently replaced but critical in the event of an emergency requirement Class IIl Parts seldom replaced Class IV Hardware e g nuts studs pins ect Class V Parts practically never requiring replacement Determine need probability coverage which is computable with a specific company s operational objectives and service parts inventory investment philosophy Then relate need probability coverage to parts classifications which will satisfy that need Guidelines are as follows Parts classification Need probability coverage Class 70 Class and II 85 Class Il and
16. ged order spare 0 ring If not damaged preserve 0 ring Remove wiper seat from front end of bush and U ring from back end of bush with FIGURE 8 FIGURE 9 2 5 mm gap in piston tape Bearing Wiper seal Piston rod O ring Note orientation Position piston rod O ring Piston rod O ring Note orientation Bush O ring SEMPELL DEWRANCE BLEED STEAM CHECK VALVES INSTALLATION AND MAINTENANCE INSTRUCTIONS C Cleaning and re assembly i Bush see Figure 8 After inspection of bearings and re fitting if required the wiper seal and U ring grooves should be wiped out and air blasted the wiper seal and O ring wiped clean and then re fitted in the positions indicated in Figure 8 Bung up each end of the bush with clean cloth Wipe clean the 0 ring groove and outside diameters of the bush and air blast Wipe clean the bush 0 ring and refit Wrap assembly in clean cloth and preserve Front cover wipe out center bore of front cover and air blast Place front face of front cover uppermost on bench Remove outer cloth from bush Align small O D of bush in center bore of front cover and rotate bush to align fixing screw holes Press bush into end cover ensuring O ring and wiper are not sheared or otherwise damaged on assembly Press bush down until flange is seated Refit fixing screws and tighten using 6 mm A F hex wrench Place front end cover on
17. h standards of precision and accuracy and must pass rigid inspection before leaving the factory It is imperative that these valves are properly installed maintained and operated to ensure optimum performance The purpose of this service manual is to instruct installation crews maintenance personnel and operators in these fundamentals This manual should be made available to these personnel at all times so that they can become and remain familiar with the details of these valves Dewrance bled steam check valves are intended for high pressure service in fluids approved by Dewrance When shipped from the Dewrance factory they are guaranteed to be in good condition however Dewrance cannot assume responsibility for damage to valves due to faulty installation improper operation or other conditions beyond its control This range of valves has been specifically designed for installation in bled extraction steam lines between steam turbines and feed water heaters but are equally applicable to reheater connections and bleed on pass out lines in process plants Their function is to prevent the reverse flow of stored steam and water from the heater or its bled steam pipe to the turbine Installation would be in a horizontal pipe as near to the turbine as possible These valves are free acting whereby the disc moves to the closed position when flow in the forward direction ceases Gravity action on the disc provides a closing moment f
18. he U ring bearings and rod wiper Push piston up to face of end cover 5 Tube lightly grease the outside diameter of the piston U ring and piston tape see Paragraph D for grease type Wipe out and air blast the tube bore and the tube end about to be fitted Fit tube over piston tape U ring and front cover spigot up to spigot 0 ring Tip the assembly up onto the tube end and lightly tap the front cover using a fiber mallet onto the tube past the spigot 0 ring taking care not to shear or otherwise damage the O ring 6 Springs and back cover place the front end cover and tube assembly on its side air blast open end of tube Wipe the springs clean and place them in the open end of the tube resting on the tube bore Wipe clean the tube end Wipe clean and air blast the spigot and inside face of the rear end cover Position the springs in their spring seat in the back of the piston and offer the back cover spring seat up to the springs checking the orientation of the two end covers i e mounting plate holes in line and rear cover silencer on the opposite side to the inlet port on the front cover 7 Refit tie rods as indicated in Figure 6 Fit ie rod front nuts ferrules to front end of cylinder and do up finger tight Check that he springs are correctly seated Then proceed to fully tighten see Paragraph E or wrench sizes in the reverse order to hat described in Figure 6
19. hieve above tolerances adaptor plate face 88 secure with lower Ensure that the face is machined square actuator nuts o C L Refit hinge pin housing 99 4 Tighten gland nuts 78a 7 Ensure gasket faces on cover 3 to body 1 5 Reconnect electrical and compressed air are clean Fit new cover gasket 17 into connections recess in body 1 6 Reinstate electrical and compressed air 8 If guide bush 80a has been replaced supplies ensure that the stem guide 160 has been 7 Screw in adjusting nut on filter regulator peened over to retain the guide bush 80a until the working air pressure is obtained refer to section VII page 14 8 Stroke valve fully open and close to check ease of operation FIGURE 5 Hinge pin housing 99 Material to be removed from this face by grinding SEMPELL DEWRANCE BLEED STEAM CHECK VALVES INSTALLATION AND MAINTENANCE INSTRUCTIONS 10 INVENTORY PHILOSOPHY The basic objective in formulating a service parts inventory philosophy is to provide prompt valve service capability thus preventing maintenance outage time extensions To accomplish this it is necessary to have immediate availability of the proper inventory of service parts for optimum valve quantities This can be achieved at a minimum of cost by defining the inventory on a frequency of need basis To assist towards this objective the field service and repair organisation of Dewrance recommends that the followin
20. ity employer 2015 Pentair plc All rights reserved w
21. lifting 9 RE ASSEMBLY REFER TO FIGURES 1 AND 2 A Pre assembly checks Ensure the following checks are performed prior to assembling the valve FIGURE 4 Disk to be peened over in 3 places Note ensure bush is fully pushed in before peening Body 1 Check the finish of the stem which operates through the gland The stem must be smooth and free from scoring Cover 3 Ensure that the body is cleaned of any other foreign debris which may have accumulated in the valve body 1 Inspect the gasket sealing face for damage 2 Inspect the internal walls of the gland box for steam cuts or pitting e Studs 28 28a and 28b Check for wear or damage replace with new ones as necessary Hinge pin 58 tis important that the pin is straight within 0 06 mm if greater that this pin must be straightened Caution take care not to damage pin during his operation e Neck bush 80 nspect bore of bush for wear or scoring replace with as necessary e Hinge pin bush 96 Check Bush for wear if damaged bush must be replaced in the following manner Using suitable punch knock back the peened metal and tap out the bush Press in new bush and secure by peening in three places as shown below Hinge pin bush 96 Disk 51 Should it be necessary to replace the hinge pin bushes Push the bushes into position and peen over in three places as shown below Note it is not recommended to re use a
22. m for cleanliness 2 Air supply low to actuator 2 Check air pressure and filter regulator 3 Gland nuts too tight Pressure should be as outlined in manual Inspect pipework for leaks 3 Tighten as outlined in manual 4 Clearance between hinge 4 Check clearance as outlined in manual pin housing bush incorrect SEMPELL DEWRANCE BLEED STEAM CHECK VALVES INSTALLATION AND MAINTENANCE INSTRUCTIONS APPENDIX 1 PNEUMATIC ACTUATOR MAINTENANCE A Dismantling procedure 1 Before starting to dismantle cylinder assembly from its installation it is important to note by an appropriate means he position of port and pipework in relation o each other and its installation 2 Remove cylinder assembly from its installation and lift clear using the lifting eye fitted 3 Place cylinder on a service bench with the ront of the cylinder towards you Front of cylinder refers to piston rod end of cylinder 4 Undo the elbow fitting pipe nut on the air supply to the valve remove the solenoid cap and undo and remove the F R L mounting plate and F R L assembly Remove the junction box plate and preserve Preserve parts means keep for later maintenance operation 5 To dismantle the cylinder the tie rod nuts on the front end of the cylinder must be loosened as indicated in Figure 6 until the installed compression springs have reached their free length Removal of tie rod nuts 1 Loosen nuts 1 and
23. ny packings or gaskets In case of defects considered to be outside the acceptable standards replacement parts should be fitted Dewrance provide in house factory repair facility and a fast response spare parts service SEMPELL DEWRANCE BLEED STEAM CHECK VALVES INSTALLATION AND MAINTENANCE INSTRUCTIONS 9 Slide stem 4 through guide bush 80a and into stem guide 160 and neck bush 80 B Assembly procedure 1 Ensure that the disk 51 and body 1 seating faces are clean Place a nylon sling 10 Fit new gland packing 68 gland 5 gland through hinge pin bushes 96 located in disk and using lifting equipment lower disk into body 1 As the disk is being lowered it will have to be pushed over at the same time until the disk comes into contact with the body seat Caution care must be taken to prevent damage to disk and body seating faces the angle of the seat to disk faces will keep the flange 30 and gland nuts 78a Using eyebolts and lifting equipment fit cover assembly over cover studs 28 making sure that the location dowel is lined up correctly Caution care should be taken not to damage cover studs 28 Support stem 4 during this operation as it could become dislodged disk in position 12 Lightly lubricate cover studs 28 with a high 2 Align hinge pin bushes 96 and slide in emperature anti seize compound and fit hinge pin 58 cover nuts 78 Gasket compression
24. om date of repair completion C Dewrance product repair by unauthorized sources Dewrance has not authorized any outside repair companies contractors or individuals to perform warranty repair service on new products or field factory repaired products of its manufacture Therefore customers contracting for such repair services from unauthorized sources must do so at their own risk Likewise if any Dewrance product falls to perform within the scope of its design TROUBLESHOOTING Problem Probable cause Body cover joint leakage 1 Gasket damaged 2 Cover nuts loose Cover gland box leaking 1 Gland packing damaged 2 Gland nuts loose Dewrance must be notified and given the opportunity to inspect and correct the problem Dewrance will not accept any backcharges for unauthorized repair sources performing corrective repairs on its products 12 TROUBLESHOOTING The following table indicates the difficulties which may be encountered the most probable cause and the necessary corrective action Corrective action 1 Disassemble valve and fit new gasket as outlined in manual 2 Tighten cover nuts as outlined in manual PADI condition as outlined in manua sassemble valve and correct discrepant 2 Tighten gland nuts as outlined in manual Disk will not open and 1 Foreign material trapped 1 Disassemble valve and correct discrepant fully close between disk and seat condition as outlined in manual Inspect syste
25. rom the fully open to fully closed position Where power assistance is required a spring return pneumatic cylinder is accommodated whilst still maintaining the automatic gravity closing feature All Dewrance bled steam check valves are based on the same seat geometry of a conical seated disc in a conical body seat The seating intensity is high enough to give a good seal and yet low enough not to cause any surface scuffing The position of the hinge pin ensures that the disc opens and closes without a rubbing action to effect a tight seal over the full range of pressures The combination of disc geometry and the body shape produce a Seat angle which gives a short disc travel as the flow falls progressively with decreasing flow This disc will be on the seat when flow ceases and before reversal takes place without slamming This arrangement gives a low pressure drop and flow under the disc assists in keeping the valve fully open over a wide range of flows SEMPELL DEWRANCE BLEED STEAM CHECK VALVES INSTALLATION AND MAINTENANCE INSTRUCTIONS FIGURE 1 Safety guard fitted only when solenoid valve has Main air supply in manual push button Filter a regulator O Do not use eyebolts for lifting valve Only use for lifting pneumatic actuator View of limit switches in direction of arrow X FIGURE 2 Scrap view of hinge pin area in direction of arrow A Figure 1 P ama on mE
26. spect for damage or distortion If damaged order spare If not damaged preserve Remove piston U ring from piston Use of a blunt flat bladed screw driver placed in the center of the U stretch the U ring over he piston lip This is permitted but caution should be taken not to damage the seating aces or U ring itself Inspect U ring for damage If damaged order a spare If not damaged preserve Remove piston tape from piston and inspect for wear If piston is worn order spare If not then preserve Note the piston tape is he use of a blunt flat bladed screw driver cut at 45 and should have a 2 5 mm gap aking care not to cause damage to wiper when fitted see Figure 9 U ring seating faces or bearing surfaces 6 Piston rod Inspect for scoring and general nspect wiper and U ring for damage wear If worn order a replacement If not or distortion If either is damaged order worn wrap ina clean cloth and preserve a spare to replace the damaged item If here is no damage preserve 2 Tube clean tube bore and inspect for scoring and wear If damaged order a new ube If not damaged cover with a clean cloth and preserve 3 Front cover spigot 0 ring Remove 0 ring and inspect for damage or distortion f damaged order spare 0 ring If not damaged preserve cover and 0 ring 4 Bush see Figure 8 Remove 0 ring from bush and inspect for damage or distortion f dama
27. t Remove screws with a 6 mm A F hex wrench Turn front end cover over and support it such that the bush is clear of the bench Push bush out from back face of front cover Preserve FIGURE 7 Do not grip on or mark in any way the piston rod surface Loosen piston rod using spanner flats only Grip piston rod piston assy by tail rod only SEMPELL DEWRANCE BLEED STEAM CHECK VALVES INSTALLATION AND MAINTENANCE INSTRUCTIONS B Inspection and spare parts 1 Spares for this cylinder are as follows 1 Spigot 0 ring front cover Bush bearings inspect bearing surfaces If 75 of the bearing surface appears to be Bronze in color the bearings will require II Bush 0 ring replacing This can be done by carefully III Piston rod 0 ring pressing the bearings out or machining IV Piston rod wiper them out Either method must result in V Piston rod U ring VI Piston U ring VII Piston tape no damage to the bush itself as this will cause damage or bad fitting of replacement bearings Replacement bearings should be The above parts can be ordered by quoting Other spares can be ordered quoting the SK o and the description of the part required RK SK SK No is stamped on the end cover ordered to the SK No and pressed in one from each end of the bush until in position shown in Figure 8 Piston Figure 9 remove piston rod O ring from centre bore of piston in
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