Operating and Installation Instructions Diaphragm Vacuum Pumps and Compressors Type Range: UN035ANP UN035.3ANP UN035.1.2SNP UN035TTP UN035ATP UN035.3ATP UN035.1.2STP UN035.1.2TTP UN035AVP UN035.3AVP UN035.1.2SVP UN035.2TTP UN035.1.2ANP UN035SNP UN035.3SNP UN035.3TTP UN035.1.2ATP UN035STP UN035.3STP UN035.1.2AVP UN035SVP UN035.3SVP Contents KNF Neuberger, Inc 2 Black Forest Rd Trenton, NJ 08691-1810 Phone: 609-890-8600 Fax: 609-890-8323 www.knf.com/usa.htm Ident#121228-210800 Revision (6/12) 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. Page About this document................................................................ 3 Use.......................................................................................... 4 Safety ...................................................................................... 5 Technical Data ........................................................................ 7 Design and Function ............................................................... 9 Installation and connection .................................................... 11 Operation .............................................................................. 12 Servicing ............................................................................... 14 Troubleshooting .................................................................... 21 Spare parts and accessories ................................................. 23 Product Return ...................................................................... 24 2 Diaphragm Vacuum Pump UN035_P About this document 1. About this document 1.1. Using the Operating Instructions The Operating Instructions are part of the pump. Carefully study the Operating Instructions before using a pump. Always keep the Operating Instructions handy in the work area. Pass on the Operating Instructions to the next owner. Project pumps Customer-specific project pumps (pump models which begin with “PU” or “MPU”) may differ from the Operating Instructions. For project pumps, also observe the agreed upon specifications. 1.2. Symbols and Markings Warning A danger warning is located here. Possible consequences of a failure to observe the warning are specified here. The signal word, e.g. WARNING Warning, indicates the danger level. Measures for avoiding the danger and its consequences are specified here. Danger levels Signal word Meaning DANGER warns of immediate danger WARNING CAUTION Consequences if not observed Death or serious injuries and/or serious damage are the consequence. warns of possible Death or serious injuries danger and/or serious damage are possible. warns of a possibly Minor injuries or damage are dangerous situapossible. tion Tab. 1 Other information and symbols An activity to be carried out (a step) is specified here. 1. The first step of an activity to be carried out is specified here. Additional, consecutively numbered steps follow. This symbol refers to important information. 3 Use Diaphragm Vacuum Pump UN035_P 2. Use 2.1. Proper use The pumps are exclusively intended for transferring gases and vapors. Owner's responsibility Operating parameters and conditions Only install and operate the pumps under the operating parameters and conditions described in Chapter 4, Technical data. Make sure that the installation location is dry and the pump is protected against rain, splash, hose and drip water. Requirements for transferred medium Before using a medium, check whether the medium can be transferred danger-free in the specific application case. Before using a medium, check the compatibility of the materials of the pump head, diaphragm and valves with the medium. Only transfer gases which remain stable under the pressures and temperatures occurring in the pump. 2.2. Improper use The pump may not be operated in an explosive atmosphere. The pump is not suitable for transferring dusts. The pump is not suitable for transferring liquids. Pumps designed to create either a vacuum or an overpressure must not be used for these two purposes simultaneously. An overpressure must not be applied to the suction side of the pump. 4 Diaphragm Vacuum Pump UN035_P 3. Safety Safety Note the safety precautions in sections 6. Installation and connection, and 7. Operation. The pumps are built according to the generally recognized rules of technology and in accordance with the occupational safety and accident prevention regulations. Nevertheless, dangers can result during their use which leads to injuries to the user or others, or to damage to the pump or other property. Only use the pumps when they are in a good technical and proper working order, in accordance with their intended use, observing the safety advice within the operating instructions, at all times. Personnel Make sure that only trained and instructed personnel or specially trained personnel work on the pumps. This especially applies to assembly, connection and servicing work. Make sure that the personnel has read and understood the operating instructions, and in particular the "Safety" chapter. Working in a safetyconscious manner Observe the accident prevention and safety regulations when performing any work on the pump and during operation. Do not expose any part of your body to the vacuum. Open housing parts with notice sticker (see fig. 1) only after separating mains plug from power source. Fig. 1: Notice sticker Handling dangerous media When transferring dangerous media, be sure to observe the safety regulations when handling these media. Handling flammable media Be aware that the pumps are not designed to be explosion-proof. Make sure the temperature of the medium is always sufficiently below the ignition temperature of the medium, to avoid ignition or explosion. This also applies for unusual operational situations. Note that the temperature of the medium increases when the pump compresses the medium. Hence, make sure the temperature of the medium is sufficiently below the ignition temperature of the medium, even when it is compressed to the maximum permissible operating pressure of the pump. The maximum permissible operating pressure of the pump is stated in the technical specifications (see section 4). If necessary, consider any external sources of energy, such as radiation, that may add heat to the medium. In case of doubt, consult the KNF customer service. Environmental protection Store all replacement parts in a protected manner and dispose of them properly in accordance with the applicable environmental protection regulations. Observe the respective national and international regulations. This especially applies to parts contaminated with toxic substances. 5 Safety Diaphragm Vacuum Pump UN035_P Standards The pumps conform to the safety regulations of the EC Directive 2004/108/EG concerning Electromagnetic Compatibility and the EC Directive 2006/42/EG concerning Machinery. The following harmonized standards have been used: IP20 DIN EN 55014-1/2 DIN EN 61000-3-2/3 DIN EN 60335-1 IP44 DIN EN 55014-1/2 DIN EN 61000-3-2/3 DIN EN 60204-1 Tab. 2 Customer service and repairs Only have repairs to the pump carried out by the KNF Customer Service responsible. Only authorized personnel should open those parts of the housing that contain live electrical parts. Use only genuine parts from KNF for servicing work. 6 Diaphragm Vacuum Pump UN035_P 4. Technical Data Technical Data Pump materials Pump type UN035ANP UN035.1.2ANP UN035.3ANP UN035ATP UN035.1.2ATP UN035.3ATP UN035AVP UN035.1.2AVP UN035.3AVP UN035TTP UN035.1TTP UN035.1.2TTP UN035.2TTP UN035.3TTP UN035SNP UN035.1.2SNP UN035.3SNP UN035STP UN035.1.2STP UN035.3STP UN035SVP UN035.1.2SVP UN035.3SVP Material* Pump head Diaphragm Valve Gasket Aluminium CR Stainless steel CR Aluminium PTFE-coated Stainless steel FPM Aluminium FPM Stainless steel FPM Aluminum with PTFE-coated PVDF plating Stainless steel FPM Stainless steel CR CR - Stainless steel PTFE-coated PTFE - Stainless steel FPM FPM - Tab. 3 *According to DIN ISO 1629 und 1043.1 7 Technical Data Diaphragm Vacuum Pump UN035_P Pneumatic Values Pump type UN035ANP UN035SNP UN035ATP UN035TTP UN035STP UN035AVP UN035SVP UN035.1.2ANP UN035.1.2SNP UN035.1.2ATP UN035.1.2TTP UN035.1.2STP UN035.1.2AVP UN035.1.2SVP UN035.3ANP UN035.3SNP UN035.3ATP UN035.3TTP UN035.3STP UN035.3AVP UN035.3SVP Delivery rate* at Maximal operating atm. pressure (l/min) pressure (bar g) 30 4 27 30 2 100 55 4 50 55 2 30 - 13 27 - 20 30 - 13 Tab. 4 8 Ultimate vacuum (mbar abs.) *Liters in standard state (1013 bar) Diaphragm Vacuum Pump UN035_P 5. Design and Function Design and Function Design UN035A_P 1 2 3 4 Pneumatic pump outlet Pneumatic pump inlet On/Off Switch Handle Fig. 2: Diaphragm Pump U 035ANP Design UN035.1.2A_P 1 2 3 4 5 6 Pneumatic pump outlet Pneumatic pump inlet On/Off Switch Pneumatic head connection 1 Handle Pneumatic head connection 2 Fig. 3: Diaphragm Pump UN035.1.2ANP 9 Design and Function Diaphragm Vacuum Pump UN035_P Design UN035.3A_P 1 2 3 4 5 6 Pneumatic pump outlet Pneumatic pump inlet On/Off Switch Handle Pneumatic head connection Silencer/filter (accessory) Fig. 4: Diaphragm pump U 035.3ANP Function diaphragm pump 1 2 3 4 5 6 7 Outlet valve Inlet valve Transfer chamber Diaphragm Eccentric Connecting rod Pump housing Fig. 5: Pump head The pump transfers, compresses (depending on pump version) and evacuates gases and vapors. The elastic diaphragm (4) is moved up and down by the eccentric (5) and the connecting rod (6). In the downward stroke it aspirates the gas to be transferred via the inlet valve (2). In the upward stroke, the diaphragm presses the medium out of the pump head via the outlet valve (1). The transfer chamber (3) is hermetically separated from the pump drive (7) by the diaphragm. 10 Diaphragm Vacuum Pump UN035_P Installation and connection 6. Installation and connection Only install and operate the pumps under the operating parameters and conditions described in chapter 4, Technical data. Observe the safety precautions (see chapter 3). 6.1. Installation Before installation, store the pump at the installation location to bring it up to room temperature. Dimensions Cooling air supply Installation location See chapter 4, Technical data, for the dimensions of pump. Install the pump so that the motor fan can intake sufficient cooling air. Make sure that the installation location is dry and the pump is protected against rain, splash, hose and drip water. Choose a safe location (flat surface) for the pump. Protect the pump from dust. Protect the pump from vibrations and jolts. 6.2. Connection Connected components Only connect components to the pump which are designed for the pneumatic data of the pump (see section 4). Pump exhaust If the pump is used as a vacuum pump, safely discharge the pump exhaust at the pump’s pneumatic outlet. Connection A marking on the pump head shows the direction of flow. 1. Remove the protective plugs from the pneumatic connectors of the pump. 2. Mount accessory silencer/filter (where applicable): If the pump is used as a vacuum pump, mount the silencer at the pressure side if necessary. If the pump is used as a compressor (not permitted with series UN 035.3) mount the filter at the suction side if necessary. − Unscrew corresponding hose connector from pump head. − Screw silencer/filter into pump head. 3. Connect the suction line and pressure line (UN035._A _P: tube inner diameter 9 mm; UN035._A _P: tube inner diameter 10 mm). 4. Lay the suction and pressure line at a downward angle to prevent condensate from running into the pump. 5. Insert the power cable’s plug into a properly installed shockproof socket. 11 Operation Diaphragm Vacuum Pump UN035_P 7. Operation 7.1. Preparing for Start-up Before switching on the pump, observe the following points: Pump Operational requirements All hoses attached properly Fan openings not blocked Specifications of the power supply correspond with the data on the pump’s type plate. The pump outlet is not closed or constricted. Tab. 9 7.2. Starting Only operate the pump under the operating parameters and conditions described in chapter 4, Technical data. Make sure the pump is used properly (see section 2.1). Make sure the pump is not used improperly (see section 2.2). Observe the safety precautions (see chapter 3). Hazard of the pump head bursting due to excessive pressure increase Do not exceed max. permissible operating pressure WARNING (see section 4). Monitor pressure during operation. If the pressure exceeds the maximum permissible operating pressure, immediately shut down pump and eliminate fault (see chapter 9. Troubleshooting). Only throttle or regulate the air or gas quantity in the suction line to prevent the maximum permissible operating pressure from being exceeded. If the air or gas quantity in the pressure line is throttled or regulated, make sure that the maximum permissible operating pressure of the pump is not exceeded. Excessive pressure (with all of the related hazards) can be prevented by placing a bypass line with a pressure-relief valve between the pressure and suction side of the pump. For further information, contact our technical adviser. Pump standstill 12 With the pump at a standstill, open pressure and suction lines to normal atmospheric pressure. Diaphragm Vacuum Pump UN035_P Operation Automatic starting can cause personal injury and pump damage When the operation of the pump is interrupted by the WARNING thermal switch, the pump will restart automatically after cooling down. After triggering of the thermal protection or in the event of power failure, remove the pump’s mains plug from the socket so that the pump cannot start uncontrollably. Attempt work on the pump only if the pump is separated from mains power. 7.3. Switching pump on and off Switching pump on The pump may not start up against pressure or vacuum during switch-on. This also applies in operation following a brief power failure. If a pump starts against pressure, it may block. This activates the thermal switch, and the pump switches off. Make sure that no pressure or vacuum is present in the lines during switch-on. Switch on pump with mains switch (see fig. 2, 3 or 4, position 3). Switching off the pump/removing from operation When transferring aggressive media, flush the pump prior to switch-off to increase the service life of the diaphragm (see section 8.2.1). Switch off pump with mains switch (see fig. 2, 3 or 4, position 3). Open pressure and suction lines to normal atmospheric pressure. 13 Servicing Diaphragm Vacuum Pump UN035_P 8. Servicing 8.1. Servicing Schedule Component Pump Diaphragm, reed valves (valve plate) Silencer/filter (accessory) Servicing interval Regular inspection for external damage or leaks Replace at the latest, when pump output decreases Change if it is dirty Tab. 10 8.2. Cleaning When cleaning, make sure that no liquids enter the inside of the housing. 8.2.1. Flushing Pump Before switching off the pump, flush it with air (if neccesary for safety reasons: with an inert gas) for about five minutes under atmospheric conditions (ambient pressure). 8.2.2. Cleaning Pump Only use solvents for cleaning if the head materials cannot be attacked (check the resistance of the material!). If compressed air is available, blow out the components. 14 Diaphragm Vacuum Pump UN035_P Servicing 8.3. Changing Diaphragm and Valves 8.3.1. Pumps with aluminium head Conditions Spare parts UN035ANP UN035.1.2ANP UN035.3ANP UN035ATP UN035.1.2ATP UN035.3ATP UN035TTP UN035.1.2TTP UN035.3TTP UN035AVP UN035.1.2AVP UN035.3AVP Pump is switched off and mains plug is removed from the socket Pump is clean and free of hazardous materials Tubes removed from pump’s pneumatic inlet and outlet Spare part* Position** Diaphragm Countersunk screw Reed valve Gasket (F) (D) Quantity per pump head 1 1 (M,P) (V) 2 1 Tab. 11 Tools Quantity 1 1 1 1 1 1 1 *According to Spare parts list, chapter 10 **According to Fig. 6. Tools/Material Allen key 3 mm Allen key 4 mm Allen key 5 mm Screwdriver blade width 6.5 Screwdriver blade width 4.0 Fork wrench 16 mm (only for two-headed pumps) Pencil Tab. 12 Information on procedure With multi-head pumps, parts of the individual pump heads can be confused. Replace the diaphragm and reed valves of the individual pump heads consecutively. Health hazard due to dangerous substances in the pump! Depending on the substance transferred, caustic WARNING burns or poisoning are possible. Wear protective clothing if necessary, e.g. protective gloves. Flush pump before replacing the diaphragm and redd valves (see section 8.2.1). 15 Servicing Diaphragm Vacuum Pump UN035_P Fig. 6: Pump parts for versions with aluminium head 1. For pumps UN035.1.2A_P and UN035.1.2TTP: On both pneumatic head connections, open the head connection union nut on one pump head and pull the hose off. 2. For pumps UN035.3A_P and UN035.3TTP: At one pump head open the union nut of pneumatic connection and pull off the tube. 3. Mark the position of the diaphragm head C in relation of the housing A with a pencil. 4. Loosen the four allen screws B and remove the diaphragm head C. 5. Unscrew the countersunk screw D, remove the retainer plate E and the diaphragm F. 6. Loosen the four screws G and remove the cover plate H. 7. Turn the counterweight J so that the connection rod K is in the mid-position; fit the new diaphragm F. 8. Place the retainer plate E on the diaphragm F and carefully but formly tighten the new countersunk screw D (torque: 5.0 Nm). 16 Diaphragm Vacuum Pump UN035_P Servicing The self-locking screw D can only be used once. 9. Change lower reed valve: − Undo the cheese head screw N and exchange the reed valve M. 10. Change upper reed valve: − Loosen the allen screws S, remove the cover plate T and the gasket V. − Undo the cheese head screw U and exchange the reed valve P; tighten the cheese head screw U. − Replace the cover plate T with a new gasket V and tighten the allen screws S. 11. Place the diaphragm head C according to the marks made previously and tighten the screws B uniformly and diagonally (torque: 10.0 Nm). 12. Turn the counterweight J to check that the pump run freely. 13. For two-headed pumps: Carry out steps 3 to 12 for the second pump head. 14. Replace the cover plate H and secure it with the four screws G. 15. For two-headed pumps: Reattach the tube of pneumatic head connection onto the hose connector and tighten the union nut. For UN035.1.2A_P and UN035.1.2TTP pumps, this applies to both pneumatic head connections. 17 Servicing Diaphragm Vacuum Pump UN035_P 8.3.2. Pumps with stainless steel head Conditions Spare parts UN035SNP UN035.1.2SNP UN035.3SNP UN035STP UN035.1.2STP UN035.3STP UN035SVP UN035.1.2SVP UN035.3SVP Motor disconnected from mains and de-energized Pump is clean and free of hazardous materials Spare part* Position** Diaphragm Countersunk screw Valve plate (F) (D) Quantity per pump head 1 1 (Z) 1 Tab. 13 Tools Quantity 1 1 1 1 *According to Spare parts list, chapter 10 **According to Fig. 7 Tools/Material Allen key 4 mm Allen key 5 mm Screwdriver blade width 6.5 Pencil Tab. 14 Information on procedure With multi-head pumps, parts of the individual pump heads can be confused. Replace the diaphragm and valve plate of the individual pump heads consecutively. Health hazard due to dangerous substances in the pump! Depending on the substance transferred, caustic WARNING burns or poisoning are possible. Wear protective clothing if necessary, e.g. protective gloves. Flush pump before replacing the diaphragm and the valve plate (see section 8.2.1). 18 Diaphragm Vacuum Pump UN035_P Servicing Fig. 7: Pump parts for versions with stainless steel head 1. For pumps UN035.1.2S_P: On the pneumatic connection between the pump heads on the suction side, pull the hose off one pump head. On the pneumatic connection on the pressure side, loosen the hose clip on one pump head and pull the hose off. 2. For pumps UN035.3S_P: Pull the pneumatic head connection hose off one pump head. 3. Mark the position of the head plate W and intermediate plate X in relation of the housing A with a pencil. 4. Loosen the allen screws Y and remove the head plate W, valve plate Z and intermediate plate X. 5. Unscrew the countersunk screw D, remove the retainer plate E and the diaphragm F. 6. Loosen the four screws G and remove the cover plate H. 7. Turn the counterweight J so that the connection rod K is in the mid-position; fit the new diaphragm F. 8. Place the retainer plate E on the diaphragm F and carefully but formly tighten the new countersunk screw D (torque: 5.0 Nm). 19 Servicing Diaphragm Vacuum Pump UN035_P The self-locking screw D can only be used once. 9. Place the intermediate plate X on the top of the diaphragm F so that it corresponds to the marks on the housing. 10. Place the new valve plate Z on the intermediate plate X. 11. Place the head plate W according to the marks made previously and tighten the screws Y uniformly and diagonally (torque: 10.0 Nm). 12. Turn the counterweight J to check that the pump run freely. 13. For two-headed pumps: Carry out steps 3 to 12 for the second pump head. 14. Replace the cover plate H and secure it with the four screws G. 15. For two-headed pumps: Pull the pneumatic head connection hose (or hoses in the case of UN035.1.2S_P pump models) back onto the hose connector. For UN035.1.2S_P pump models: Retighten the hose clip on the pneumatic head connection on the pressure side. 20 Diaphragm Vacuum Pump UN035_P Troubleshooting 9. Troubleshooting Extreme danger from electrical shock! Disconnect the pump power supply before working on the pump. DANGER Make sure the pump is de-energized and secure. Check the pump (see Tab. 15 to 18). Pump does not transfer Cause No voltage in the power source Fault remedy Check room fuse and switch on if necessary. Thermal switch has operated following to over-heating. Disconnect pump from mains. Allow pump to cool. Trace cause of over-heating and eliminate it. Check connections and lines. Remove blockage. Check external valves and filters. Connections or lines blocked. External valve is closed or filter is clogged. Condensate has collected in pump head. Diaphragm or reed valves (valve plate) are worn. Detach the condensate source from the pump. Flush pump (see Section 8.2.1). Replace diaphragm and reed valves (valve plate), (see Section 8.3). Tab. 15 Flow rate, pressure or vacuum too low The pump does not achieve the output specified in the Technical data or the data sheet. Cause Fault remedy Condensate has collected in Detach the condensate source from the pump. pump head. Flush pump (see Section 8.2.1). There is gauge pressure on Change the pressure conditions. pressure side and at the same time vacuum or a pressure above atmospheric pressure on suction side. Disconnect pump from system to determine output values. Pneumatic lines or connection parts have an insufficient cross Eliminate throttling (e.g. valve) if necessary. section. Use lines or connection parts with larger cross section if necessary. Leaks occur on connections, Check that tubes sit correctly on hose nozzles. lines or pump head. Replace leaky tubes. Eliminate leaks. Connections or lines completely Check connections and lines. or partially jammed. Remove the jamming parts and particles. Head parts are soiled. Clean head components. Diaphragm or reed valves (valve plate) are worn. Replace diaphragm and reed valves (valve plate), (see Section 8.3). 21 Troubleshooting Diaphragm Vacuum Pump UN035_P Flow rate, pressure or vacuum too low The pump does not achieve the output specified in the Technical data or the data sheet. Cause Fault remedy Check the tubing for leaks. After diaphragm and reed valves (valve plate) have been Pumps UN035_A_P and UN035_TTP: replaced Possibly carefully tighten the screws (B) and (S) (see fig. 6) crosswise. Pumps UN035_S_P: Possibly carefully tighten the screws (Y) (see fig. 7) crosswise. Tab. 16 Pump is switched on, but does not run, the on/off-switch on the pump is not lit Cause Pump is not connected with the power source. No voltage in the power source Fault remedy Connect pump to mains power. Check room fuse and switch on if necessary. Tab. 17 Pump is switched on, but does not run, the on/off-switch on the pump is lit Cause The thermal switch has opened due to overheating Cause Remove pump´s mains plug from the socket. Allow pump to cool. Trace cause of over-heating and elimate it. Tab. 18 Fault cannot be rectified If you are unable to determine any of the specified causes, send the pump to KNF Customer Service (see first page for the address). 1. Flush the pump to free the pump head of dangerous or aggressive gases (see Section 8.2.1). 2. Clean the pump (see Section 8.2.2). 3. Send the pump to KNF with a filled out decontamination declaration (see chapter 11) and specification of the medium transferred. 22 Diaphragm Vacuum Pump UN035_P Spare parts and accessories 10. Spare parts and accessories Spare parts UN035ANP UN035.1.2ANP Spare part Diaphragm Countersunk screw Reed valve Gasket Position* (F) (D) (M, P) (V) UN035.3ANP Order No. 001312 110711 001328 001326 Tab. 19 According to Fig. 6 UN035ATP UN035.1.2ATP UN035.3ATP UN035TTP UN035.1.2TTP UN035.3TTP Spare part Diaphragm Countersunk screw Reed valve Gasket Position* (F) (D) (M, P) (V) Order No. 001406 110711 001328 011796 Tab. 20 UN035AVP According to Fig. 6 UN035.1.2AVP Spare part Diaphragm Countersunk screw Reed valve Gasket Position* (F) (D) (M, P) (V) UN035.3AVP Order No. 001405 110711 001328 011796 Tab. 21 UN035SNP According to Fig. 6 UN035.1.2SNP Spare part Diaphragm Countersunk screw Valve plate Position* (F) (D) (Z) Tab. 22 UN035STP UN035.3SNP Order No. 001312 110711 001308 *According to Fig. 7 UN035.1.2STP Spare part Diaphragm Countersunk screw Valve plate Position* (F) (D) (Z) UN035.3STP Order No. 001406 110711 001407 Tab. 23 UN035SVP *According to Fig.7 UN035.1.2SVP Spare part Diaphragm Countersunk screw Valve plate Tab. 24 Position* (F) (D) (Z) UN035.3SVP Order No. 001405 110711 001404 *According to Fig. 7 23 Product Return Diaphragm Vacuum Pump UN035_P 11. Product Return Î KNF provides warranty and non-warranty repair services for all products. Î A Return Material Authorization (RMA) number is required for all product returns. • To receive an RMA number, submit a completed Decontamination Declaration form to [email protected] Î The Decontamination Declaration form can obtained from our website or by contacting KNF Technical Services. KNF Neuberger, Inc 2 Black Forest Rd Trenton, NJ 08691-1810 Phone 609-890-8600 Fax 609-890-8323 www.knf.com/usa.htm 24 • http://www.knf.com/pdfs/decontamdec.doc • Phone: 609-890-8600 Î Product return instructions will be provided when the RMA is issued.
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