Wheel operated residual pressure cylinder valve (Inline) in O-ring seal design for technical and medical gases

Transcription

1 Wheel operated residual pressure cylinder valve (Inline) in O-ring seal design for technical and medical gases IRPV-10 I/O IRPV-10 I/C For oxygen, inert, high purity and medical gases For carbon dioxide and carbon dioxide gas mixtures Prevents ingress of contaminants by maintaining positive pressure relative to atmosphere within the cylinder Incorporates non-return function to prevent back flow of fluids into the cylinder from a higher pressure source Eliminates need to vacuum and purge cylinder before filling Increases cylinder life by preventing internal corrosion ISO 9001 and TPED certified valve manufacturer

2 Features and benefits for best-in-class performance Series IRPV-10 I/O a b Residual Pressure Device (RPD) Quad ring requires less squeeze and offers improved life Residual pressure unit secured inside valve outlet using special assembly tool Piston length may be modified to suit buyer s filling connector Oxygen compatible and corrosion resistant copper beryllium spring Close tolerances ensure quick and positive shut off with no popping/noise over full range of flow discharge Three flute housing design provides high flow Dimensions are in mm Dimensions shown are for 25E inlet and DIN 9 outlet Depends upon outlet connection Depends upon inlet connection 3/4 HEX AF 33.0 a Wrench flat 30.0 Main shut-off mechanism High durometer back-up ring protects extrusion of O-ring EPDM O-ring provides external tightness past top spindle over entire temperature and pressure range PA 66 thrust washer reduces friction and provides external tightness at high pressure Metal sealing prevents leakage through gland nut threads Naval brass top and bottom spindle provide resistance to excessive torque. The top spindle is designed to fail first to allow valve repair under pressure PA 66 soft seat, precision machining and effective lubrication of moving parts provides long life and low torque operation Inlet, outlet connection and dip tube threads as per requirement Design Specifications Closing off pressure Opening pressure 3-5 bar 5-8 bar MIN life (RPD) MIN life (main shut-off mechanism) cycles 2000 cycles Operating and storage temperature range -20 C to + 65 C MIN closing torque 3 Nm Gland nut installation torque Nm RPD installation torque 5 Nm Maximum stroke length of piston 3.25 mm Flow coefficient (C v ) 0.35 Maximum test pressure (TP) 276 bar Lubricant (RPD) - For oxidizing gases Gleitmo For non-oxidizing gases Krytox GPL 225 Lubricant (main shut-off mechanism) - For oxidizing gases Krytox NRT For non-oxidizing gases Krytox GPL 225 MAX weight of package mass without valve 100 kg protection Testing and certification Valve meets EN ISO and EN ISO , tested by BAM Berlin Production testing as per EN ISO Certified by BAM Berlin to European Transportable Pressure Equipment Directive (TPED) and available with mark

3 3/4 HEX AF Features and benefits for best-in-class performance Series IRPV-10 I/OV (top outlet configuration) Main shut-off mechanism PA 66 soft seat, precision machining and effective lubrication of moving parts provides long life and low torque operation High durometer back-up ring protects extrusion of O-ring EPDM O-ring provides external tightness past top spindle over entire temperature and pressure range Naval brass top and bottom spindle provide resistance to excessive torque. The top spindle is designed to fail first to allow valve repair under pressure PA 66 thrust washer reduces friction and provides external tightness at high pressure Metal sealing prevents leakage through gland nut threads Inlet and outlet connection as per requirement Dimensions are in mm Dimensions shown are for 25E inlet and BS-3 outlet a b 39.5 Depends upon outlet connection Depends upon inlet connection Wrench flat 30.0 Residual Pressure Device (RPD) Residual pressure unit secured inside valve outlet using special assembly tool Piston length may be modified to suit buyer s filling connector Close tolerances ensure quick and positive shut off with no popping/noise over full range of flow discharge Quad ring requires less squeeze and offers improved life Three flute housing design provides high flow Oxygen compatible and corrosion resistant copper beryllium spring Design Specifications Closing-off pressure Opening pressure 3-5 bar 5-8 bar MIN life (residual pressure device) MIN life (main shut-off mechanism) cycles 2000 cycles Operating and storage temperature range -20 C to + 65 C MIN closing torque 3 Nm Gland nut installation torque Nm RPD installation torque 10 Nm Maximum stroke length of piston 3.25 mm Flow coefficient (C v ) 0.35 Maximum test pressure (TP) 276 bar Lubricant (RPD) - For oxidizing gases Gleitmo For non-oxidizing gases Krytox GPL 225 Lubricant (main shut-off mechanism) - For oxidizing gases Krytox NRT For non-oxidizing gases Krytox GPL 225 MAX weight of package mass without valve 100 kg protection Testing and certification Valve meets EN ISO and EN ISO , tested by BAM Berlin Production testing as per EN ISO Certified by BAM Berlin to European Transportable Pressure Equipment Directive (TPED) and available with mark

4 Features and benefits for best-in-class performance Series IRPV-10 I/C a b Residual Pressure Device (RPD) Quad ring requires less squeeze and offers improved life Residual pressure unit secured inside valve outlet using special assembly tool Piston length may be modified to suit buyer s filling connector Corrosion resistant copper beryllium spring Close tolerances ensure quick and positive shut off with no popping/noise over full range of flow discharge Three flute housing design provides high flow Dimensions are in mm Dimensions shown are for 25E inlet and DIN 6 outlet Depends upon outlet connection Depends upon inlet connection 3/4 HEX AF Wrench flat a 5.00 Main shut-off mechanism High durometer back-up ring protects extrusion of O-ring EPDM O-ring provides external tightness past top spindle over entire temperature and pressure range PA 66 thrust washer reduces friction and provides external tightness at high pressure Metal sealing prevents leakage through gland nut threads Naval brass top and bottom spindle provide resistance to excessive torque. The top spindle is designed to fail first to allow valve repair under pressure PRD design uses corrosion resistant nickel burst disc. Copper gasket seals and protects burst disc PA 66 soft seat, precision machining and effective lubrication of moving parts provides long life and low torque operation Inlet, outlet connection and dip tube threads as per requirement Design Specifications Closing off pressure Opening pressure 3-5 bar 5-8 bar MIN life (RPD) MIN life (main shut-off mechanism) cycles 2000 cycles Operating and storage temperature range -20 C to + 65 C MIN closing torque 3 Nm Gland nut installation torque Nm RPD installation torque 5 Nm Maximum stroke length of piston 3.25 mm Flow coefficient (C v ) 0.70 Maximum test pressure (TP) 360 bar Lubricant (RPD) - For CO 2 and CO 2 gas mixtures Gleitmo For inert gases Krytox GPL 225 Lubricant (main shut-off mechanism) Gleitmo 591 MAX weight of package mass without valve 100 kg protection Testing and certification Valve meets EN ISO and EN ISO , tested by BAM Berlin Production testing as per EN ISO Certified by BAM Berlin to European Transportable Pressure Equipment Directive (TPED) and available with mark

5 Material of construction and assembly arrangement SeriesIRPV-10I/O&I/C Wheel cover PA Handwheel nut Brass Plain Washer Brass 9 Handwheel 30%glassfilledPA6V-0with brass insert/aluminium 8 Gland nut 7 Freecuttingbrass 5 3 O-ring EPDM Top spindle Naval brass Back-Up Ring EPDM 6 Thrust washer PA66 4 Bottom spindle assembly for IRPV-10 I/O 2b NavalbrasswithPA66seatinsert OR Bottom spindle Assembly for IRPV-10 I/C NavalbrasswithPA66seatinsert 2a 13 RPD PRD assembly 12 1 Valve body Low tensile brass

6 Material of construction and assembly arrangement Series IRPV-10 I/OV RPD 12 Bottom spindle assembly NavalbrasswithPA66seatinsert 2 Thrust washer PA66 Back-Up Ring EPDM 4 6 Handwheel 30%glassfilledPA6V-0with brass insert/aluminium 9 Valve body Low tensile brass Top spindle Naval brass 1 O-ring EPDM 3 5 Gland nut Free cutting brass 7 Wheel cover PA6 Handwheel nut Brass 10 Plain Washer Brass 8 11

7 IRPV-10 accessories RPD assembly tool (SPHC002) Features Material - High Carbon High Chromium Prevents over tightening and damage to the RPD Residual Pressure checking tool (CTNY001) Features Machined from PA 6 rod to avoid damage to RPD Residual pressure is checked by observing escaping gas by pushing the tool against the piston RPV filling connector Nut Body Connector EPDM O-ring Valve outlet connection EPDM O-ring Monel pin Features One end of the RPV filling connector is machined as per standard outlet connection Monel pin and O-ring seal prevents damage to the RPD and valve outlet Design, length of pin can be customized as per buyer s filling manifold

8 Frequently asked questions (FAQ) Series IRPV-10 1) Why the need of a Residual Pressure Valve (RPV)? In the past, the industry relied on users not to allow backflow into cylinders. Fillers typically relied on prefill inspection procedures to identify potentially contaminated cylinders returned from customers. Despite these measures, incidents caused by backflow of contaminants into cylinders have occurred, highlighting the need for RPV. Reports from the EIGA Cylinder Data Base indicate that approximately 30% of all cylinder incidents reported were the result of internal corrosion. As a result, cylinder valves that retain a residual positive pressure in a gas cylinder and prevent backflow by means of a non-return device have been available for many years. Important benefits of RPV include preventing moisture ingress and contamination if the valve operating mechanism (main shut-off) is left open. This reduces the potential for internal cylinder corrosion. Additional benefits include productivity improvements in the cylinder fill operation and reducing cylinder maintenance. European regulations and international directives necessitate the need for RPV and even allow a longer period between cylinder retesting if the cylinders are equipped with RPV. 2) What is the basic difference between inline and offline RPV? a) In offline RPV, the valve outlet is offset with respect to the inlet plane and Residual pressure device (RPD) is behind the valve outlet. In inline RPV, RPD is installed within the outlet. Inline RPV is mainly used for valve with external threaded outlet with sealing on the face. Offline RPV design can be designed with any outlet but is mainly used for outlets with internal threads and external threaded outlets having seating in the cone. b) Offline RPV provides larger flow capacity compared to inline RPV because the inline RPV flow capacity is constrained by the need to accommodate the RPD within the space available between the valve outlet threads. c) Offline RPV may be provided with or without a non-return device. Inline RPV is always designed with non-return device. The non-return device requires a RPV filling connector to fill the cylinder. 3) Would the "Tekno" RPV filling connector be compatible with our filling manifold? One end of the RPV filling connector has a Monel pin (fixed or retractable) to overcome the non-return function of the RPD while the other end is machined as per the valve outlet connection. This allows the standard non-rpv filling connector on the filling hose to be connected to the RPV filling connector. The back end of the RPV filling connector can also be designed to directly connect with the filling or evacuation hose. 4) What kind of maintenance is required for IRPV-10 valves? What spares should be stocked for repair? IRPV-10 I/O and IRPV-10 I/C main shut-off mechanism use same parts used in CWH-10/O and CWH-10/C design respectively (Also common with CRPV-10/O and CRPV-10/C valve designs). RPD is supplied as an assembled cassette for replacement. NOTE Special tool is required to disassemble and assemble the RPD. 5) Would IRPV-10 valves be compatible with RPV filling connector provided by other valve manufacturers for their RPVs? The RPV filling connectors may vary between different manufacturers. Therefore the compatibility of IRPV-10 design with RPV filling connector of other manufacturers needs to be determined before use. IRPV-10 piston length can be suitably modified at the design stage to facilitate our valves to be used with the RPV filling connector available at the customer facility.

9 Frequently asked questions (FAQ) Series IRPV-10 6) Are the RPV filling connectors compatible with simple valve? The RPV filling connector with a fixed (rigid) pin may be used to fill simple valve depending upon the outlet connection configuration and length of the pin. RPV filling connector with retractable pin design (spring loaded) can be used to fill simple valve. 7) How do we vacuum the cylinder fitted with IRPV-10 design? To vacuum the cylinders before filling, the RPV filling connector should be used. 8) What pre-fill inspection should be carried out on the RPV? Besides inspecting the RPV visually for abuse, mishandling and damage, the functionality of the RPD should be checked by inserting the checking tool against the piston. The sound of escaping gas indicates residual pressure in the cylinder. 9) As customers handle cylinder roughly and damage / break the handwheel, can RPV be supplied in key operation? The handwheel prevents the user from imparting a greater torque than required to operate the valve. Since a key operated valve invariably results in excessive torque being applied to the operating mechanism invariably resulting in damage, we only offer handwheel operated RPV. 10) When the handwheel is broken or removed, plant operators use adjustable spanners to operate the valves. How resistant is the valve operating mechanism to excessive torque? IRPV-10 design has been tested for excessive torque up to a torque of 38 Nm in both opening and closing direction. This is ten times the minimum closing torque of 3 Nm. 11) Is PA 66 soft seat and thrust washer compatible with oxygen service? As per EN ISO , it is not possible to make simple conclusion regarding compatibility of nonmetallic material with oxidizing gases. The evaluation needs to be made considering a) Ignition property of the non-metallic material and its volume. b) Material's toxic by-products and hazards if combustion/decomposition occurs. c) Valve design's susceptibility to ignition. PA 66 is widely used valve seating material for oxygen service. It is in compliance with EIGA IGC/Doc 73/00/E guideline to not employ fluorinated polymers like PTFE, PCTFE in gas wetted duty whose combustion products are toxic for medical or breathing service. IRPV-10 I/O design has been successfully tested for ignition resistance (OPST) at WP-230 Bar (TP-276 Bar) to ensure compatibility of valve design and material of construction with oxygen and other oxidizing gases. 12) How should the plant operator handle breakage of top spindle on a pressurized cylinder? IRPV-10 design fails safely when the operating mechanism is inadvertently over torqued in both opening and closing direction. The top spindle is designed to fail first leaving bottom spindle intact to allow safe cylinder recovery procedure. The top spindle can be replaced on a closed valve, securing the contents of the cylinder.

10 Frequently asked questions (FAQ) Series IRPV-10 13) We experience ejection of the operating mechanism in some valve designs while the valve is opened. Does the design address this issue? In IRPV-10 design the gland nut thread has a finer pitch than the bottom spindle threads providing a mechanical lock which prevents ejection of the operating mechanism even if the gland nut is loose while the valve is being opened. 14) Why lubrication is provided on oxygen valves contrary to the belief that cylinder valves should be free from oil and grease? Use of compatible and suitably rated lubricants for intended gas service is necessary to reduce wear in moving parts, prevent seizing and galling and ensure smooth operation. 15) What refurbishing tools are required for maintenance? The valve body internal threads or seat area are seldom damaged by frequent use and excessive torque on the operating mechanism. Therefore no special tools except RPD assembly tool are required for refurbishing. 16) Is it possible to replace PA 66 seating? PA 66 seating has a high cycle life and load bearing capacity but if the seating is worn out, the bottom spindle assembly needs to be replaced as the soft seat is fitted in the bottom spindle by special crimping operation which cannot be replicated at users end. 17) How to handle leakage from the gland? In IRPV-10 design, the gland nut abuts with the valve body providing metal to metal seal. This prevents the need to tighten gland nut unless the gland nut is inadvertently loosened in service due to external impact. In case of gland leakage a) If leakage is occurring between top spindle and gland nut bore - Clean O-ring / Back-up ring. Replace if necessary. b) If leakage is occurring through gland nut threads tighten gland nuts between Nm. Caution Do not use PTFE tapes on the gland nut threads. 18) What is the benefit of capsule design safety assembly? PRD design uses Nickel (Copper for hydrogen and carbon monoxide service) burst disc and copper sealing washer. The design allows the PRD assembly to be tightened at 35 Nm providing security from loosening. The PRDs are colour coded to identify the burst disc range. NOTE We supply spare PRD assembly consisting of retainer nut, burst disc and sealing gasket to prevent incorrect installation. 19) Is inspection of RPV filling connector required before filling? Before using RPV filling connector, it should be inspected for significant wear of all components, especially the condition of the actuation pin. RPV filling connectors with a bent or broken actuation pin should be repaired or replaced before use. 20) How should the RPV be removed from the cylinder? During removal of RPV s from cylinders, an additional verification is required to ensure that the cylinder does not contain retained pressure which may lead the operator to believe that a cylinder under pressure is empty because no gas is being emitted from the open valve. The use of a RPV filling connector required for complete depressurisation of the cylinder fitted with RPV. It is recommended to attach a RPV filling connector after venting to allow the residual pressure to be released from the cylinder.

11 Frequently asked questions (FAQ) Series IRPV-10 21) Why does the specification give maximum test pressure and not working pressure of the valve design for liquefiable gases? How does it relate to the burst disc pressure range? As per EN ISO 10297, the term "working pressure" is only used with respect to compressed gases while the term "Valve test pressure" is used for liquefiable gases and is equal to the test pressure of the cylinder depending on the corresponding filling ratio as given in P200 of European agreement concerning the international carriage of dangerous goods by road (ADR). For compressed gases, test pressure = 1.2 X working pressure The rated burst disc pressure depends upon the test pressure of the cylinder and the filling ratio used by the filler. 22) At what torques should the cylinder valve be installed on the cylinder? We recommend valving procedure and torque guidelines as per EN ISO NEVER use wrenches or other persuaders to operate the valve. 2. Valving tools (e.g. sockets or jaws) used to screw the valve into the cylinder must only make contact with the flats provided in the valve body. The tools should fit the valve properly without causing damage. 3. Over-torquing the valve into the cylinder must be avoided as they cause high stresses in the cylinder neck, leading to overload failures. Over-torquing also leads to irreparable damage to the valve stem. Disclaimer 1. While proper use and good maintenance would significantly enhance life of the valve, the recommendations and suggestions in the FAQ are not meant to substitute existing plant procedures. 2. Repair and maintenance should only be carried out by trained personnel who fully understand the valve design.

12 Natun Rasta, Bilkanda, 24 Parganas (N) Kolkata , West Bengal, India Ph , Fax post@teknovalves.com, Web Copying or extraction from this document shall not be done without Tekno Valves permission, since information contained herein includes proprietary information. Last updated 22 nd April, 2016 P.Halder