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O PERATION AND M AINTENANCE FOR JMI S UBMERSIBLE P ROPELLER P UMPS J.M.I CO., LTD.

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Presentation on theme: "O PERATION AND M AINTENANCE FOR JMI S UBMERSIBLE P ROPELLER P UMPS J.M.I CO., LTD."— Presentation transcript:

1 O PERATION AND M AINTENANCE FOR JMI S UBMERSIBLE P ROPELLER P UMPS J.M.I CO., LTD

2 T ABLE OF CONTENTS 1. PRODUCT DESCRIPTION 2. PROTECTION DEVICES - Thermal protector (Stator Winding Temperature Sensor) - Seal Sensor (Leakage Detector) - Bearing Temperature Sensor - Moisture Sensor (optional) 3. INSTALLATION 4. BEFORE STARTING 5. ELECTRICAL WORKS 6. OPERATION 7. INSPECTION 8. TROUBLE SHOOTING 9. DESIGN OF PROPELLER PUMP STATION

3 1. P RODUCTION DESCRIPTION Watertight cable entrance with anti-wicking block prevents incursion of water into the motor even if the power cable is cut or damaged Highly efficient, continuous duty, air filled motor assures low operating cost and maximum life expectancy. Double inside mechanical seal with silicon carbide faces guarantees long-lasting operation without leakage. Simple and compact mechanism prevents twisting of power cables and pump itself Highly reliable thermal protector prevents motor failure caused by heavy overloads, stalling etc. Highly sensitive float type sensor gives warning of impending seal failure in advance. Double shielded, permanently lubricated, high temperature ball bearing rated for 100,000 hours provide for extended operational life. Highly-efficiency and high-capacity impeller offers tremendous advantages Design

4 A. Impeller The pump is equipped with a propeller of Aluminum Bronze or Stainless Steel (optional). B. Shaft The shaft and rotor are integrated as one part. The shaft is completely sealed and will not come into contact with the pumped liquid. Material: Stainless Steel C. Shaft Seal The pump has double mechanical seals, which provides the necessary isolation between the electric motor and the pumped liquid. Material: Upper Seal: Silicon carbide – Silicon carbide Lower Seal: Silicon carbide – Silicon carbide D. Bearings The pump bearings are designed for at least 50,000 hours of operation. The lower bearing consists of ball bearings. The upper bearing consists of a roller bearing. Main parts

5 The features of JPP submersible propeller pumps are: - Compact design provides for easy handling and installation - High capacity with low head design is versatile in application - Simple mechanism provides for easy maintenance special piping or housing is required - Propeller individually designed for duty point. Features Applications JPP submersible propeller pumps are designed especially for: - Flood and storm water control - Drainage/irrigation with large volumes - Raw water intake - Large scale municipal sewage treatment plant - Circulation of large quantity of water in water theme parks and the like.

6 Specification StandardOptions Discharge Size400 ~ 1,800 mmUp to 2,000mm Column Diameter600 ~ 2,000 mmUpon request Power Range22 ~ 750 KWUp to 1,000 KW Water temperature 0 ~ 40 Impeller typePropeller Performance Range - Capacity 20 ~ 480 /min Upon request - HeadUp to 9 m Materials of Construction - Casing & Wearing ringCast Iron - Wearing ringStainless steel - Propeller VaneStainless steelAluminum bronze - ShaftStainless steel - Motor frameCast Iron Submersible Electric Motor - TypeAir filled, Squirrel cage induction motor - InsulationClass F - Power cable length8m

7 Part list

8 NoITEMMATERIALSTANDARD ASTMBSJIS 1Power Cable---- 5Backup Ring304 SSASTM A276, 304BS970-70, 304S15SUS304 6Stuffing BoxCast IronASTM A48, Cl. 30BS , 180FC Hex. Bolt304 SSASTM A276, 304BS970-70, 304S15SUS304 10Propeller VaneSSC 13ASTM A743, CF-8-SCS13 11Propeller CapCast IronASTM A48, Cl. 30BS , 180FC Wrench Bolt304 SSASTM A276, 304BS970-70, 304S15SUS304 13Propeller HubCast IronASTM A48, Cl. 30BS , 180FC Head CoverCast IronASTM A48, Cl. 30BS , 180FC Mechanical sealSiC / SiC--- 26Oil SealNBR--- 29Seal ChamberCast IronASTM A48, Cl. 30BS , 180FC Suction CasingCast IronASTM A48, Cl. 30BS , 180FC Vane Fixed Plate304 SSASTM A276, 304BS970-70, 304S15SUS304 47Discharge CasingCast IronASTM A48, Cl. 30BS , 180FC Motor BracketCast IronASTM A48, Cl. 30BS , 180FC Upper Bearing Thermal Protector Motor Shaft410 SSASTM A276, 410BS970-70, 410S21SUS410 55Rotor Stator Thrust Bearing Bearing HousingCast IronASTM A48, Cl. 30BS , 180FC Bearing CoverCast IronASTM A48, Cl. 30BS , 180FC Upper Bearing CoverCast IronASTM A48, Cl. 30BS , 180FC Motor FrameCast IronASTM A48, Cl. 30BS , 180FC Sunk Key410 SSASTM A276, 410BS970-70, 410S21SUS410 68Lifting RingSteel--- 82Roller Bearing CoverCast IronASTM A48, Cl. 30BS , 180FC Radial Bearing Seal Leakage Sensor Cable BendCast IronASTM A48, Cl. 30BS , 180FC Terminal BoardCast IronASTM A48, Cl. 30BS , 180FC Bearing Temp. Sensor Shaft clamp Washer304 SSASTM A276, 304BS970-70, 304S15SUS Wearing RingSSC 13ASTM A743, CF-8-SCS13 OILISO VG #32--- PAINTEpoxy Paint Black--- PREMIEREpoxy Paint Brown-Red--- Material

9 Exploded diagram No Description No. Description

10 Overhaul sequence 1) Lifting ring 2) Empty Oil 3) Head cover 4) Terminal board 5) Discharge casing 6) Cap 7) Vane washer 8) Vane 9) Key 10) Seal chamber 11) Suction casing 12) Mechanical seal 14) Motor bracket 13) Bearing housing 15) Upper bearing cover 16) Lower seal chamber 17) Lower bearing cover 18) Lower stop ring 19) Bearing

11 2. P ROTECTION DEVICES Sensors for JPP SensorBuilt - inMotor ratingType Thermal protector (TP) Standard22 KW aboveBi-metal Optional 90 KW abovePT-100 Ohm Seal Leakage Sensor (SS)Standard22KW aboveFloat type Bearing Sensor (BS) Optional22KW ~75KW PT-100 Ohm Standard90 KW above Moisture Sensor (MS)Optional90 KW aboveElectrode

12 Location of sensors

13 A temperature sensor is installed in the stator windings of motor Which continuously monitors temperature of the motor. The sensor has two lead wires and is identified by the letters TP. The thermal sensor is a Bimetal (General) or PT-100 Ohms type (Optional). The function operates if the motor stator winding temperature exceeds a programmable preset temperature. This happens when the temperature reach to over 100 °C and The indication lamp (TP) of Monitoring Unit System (MUS) turns on. The use of a MW tester to test this alarm is prohibited due to the low resistance of the sensor circuits. Thermal protector (Winding temperature sensor)

14 A seal leakage sensor is installed on the bearing housing. This is an Float type sensor to determine if water penetrates into the oil chamber due to the abrasion or mechanical seal failure. The sensor has two lead wires and is identified by the letter SS. The function operates if the mechanical seal fails allowing water to penetrate the oil chamber. The indication lamp (SS) of Monitoring Unit System (MUS) turns on. And the mechanical seal must be replaced and the oil chamber refilled with fresh oil to the correct level The use of a MW tester to test this alarm is prohibited due to the low resistance of the sensor circuits. Seal leakage sensor(Seal sensor)

15 Bearing temperature sensor This sensor is installed in the lower bearing housing and monitors the bearing temperature. The sensor has two lead wires and identified by the letter BS. The bearing temperature sensor is a PT-100 Ohms type sensor. The function operates if the temperature of the bearing exceeds a programmable preset temperature. When this happens, The indication lamp (SS) of Monitoring Unit System (MUS) turns off. If this function is activated, the bearings should be replaced and the motor inspected and serviced. The real time bearing temperature can be read from the digital meter on the front of MUS. The factory preset temperature for the bearing temperature alarm is 110°C. If necessary, the value can be changed by authorized engineer. The use of a MW tester to test this alarm is prohibited due to the low resistance of sensor circuits.

16 An optional moisture sensor may be installed in the electrical junction box to guard against moisture penetration which may cause a short circuit of cable by moisture. The sensor, if fitted, is connected by two lead wires and is identified by letter MS. The moisture sensor is electrode type sensor. The function operates when moisture is detected in the junction Box. When this happens, The indication lamp (MS) of Monitoring Unit System (MUS) turns on. If this happens, the integrity of the cable entry must be restored and the insulation resistance of the motor checked. If less than 1.5 kW, the motor must be dried and preferable serviced before running again. The use of a MW tester to test this alarm is prohibited due to the low resistance of the sensor circuits. Moisture sensor (Optional)

17 Dimension & diagram of MUS To operate MUS in control panel, AC220V and relay to get output through it should be prepared. It also needs a space to be installed in the control panel.

18 Operating manual of MUS J.M.I Monitoring Unit Systems (hereinafter MUS) is installed in MCC (motor control center) and accordingly MCC manufacturer should prepare the wiring work for MUS. So it is strongly recommended to hand over MUS to MCC manufacturer as soon as MUS manufacturer is selected. MUS is very sophisticated instrument and it has many useful functions. So be careful to use it properly. Followings are the operating drills for MUS 1) First of all, please check input line voltage to MUS whether it is within 220V AC, 50 or 60Hz.( both of 50HZ and 60HZ are available) 2) Connect all the sensor wires to proper terminals on MUS There is a marking in the terminal block for the sensors, so it is easy to identify the terminals for each sensor 3) Then set the operating mode with following procedure. (1) Set the bearing temperature (110 ) by using up/down arrow key. (Generally, Centrifugal pump - 80 and Mixed / Axial flow pump ) (2) Turn on power switch of MUS. The display window shows the temperature of bearing. 4) MUS are consist of following, Mode : M/S + S/S + T/P + B/S where, M/S = Moisture detecting sensor in junction box (Optional) S/S = Seal leakage detector T/P = Thermal protection (Bimetal type sensor) B/S = Bearing temperature detector 5) When the pump is working at normal, M/S, S/S and T/P indication lamps are under extinction and Only B/S indication lamp keeps turning on. 6) In return, M/S, S/S and T/P lamps are turning on and only B/S lamp is turning off in case of faulty function in the pump. After acknowledging the error, switch off MUS and remove the faulty source. In case of the faulty source is removed, Go back to the first procedure.

19 Safety precautions In order to minimize the risk of accidents in connection with the service and installation work, following safety precautions should be taken. 1. Make sure all lifting equipment is in good condition. 2. Use safety equipment, i.e. helmet, shoes and goggles. 3. Use a licensed electrician and be aware of the risk of electrical accident. 4. Be aware and do not ignore the risk of drowning. 5. A first-aid kit must be handy at all times. 6. Follow all health and safety rules of local ordinances and codes. 3. INSTALLATION Handling equipment Lifting equipment will facilitate handling of the pump. Only lift and handle the pump using a winch or wire rope attached to the lifting lug of the pump. NEVER HANDLE THE PUMP BY THE POWER CABLE. The capacity of the lifting equipment must be sufficient to handle the load plus an additional 50% safety factor. Make sure that the lifting equipment is securely anchored to a strong base before using. WARNING! DO NOT STAND UNDERNEATH THE PUMP WHEN IT IS BEING LIFTED Cable protection If the pump is not going to be installed immediately, the open end of the power cable must be protected from moisture which could otherwise penetrate the motor winding. This should be done as soon as the pump Delivered..

20 Installation of submersible propeller pump The pump is installed in a stationary discharge tube(Column pipe). The pump operates completely submerged in the discharge flow and does not require any additional protection. In addition to the pump, the following items are required: - Column pipe with bottom locating plate(sole plate) in which the pump installed. - Cable holder for securing the cable and regulating the height of level sensors. Take particular care installing the propeller pump because the installation method is not similar to that of other type of submersible pump. The installation should be carried out by qualified personnel experienced in the installation of this type of pump. The pump must be installed in compliance with this instruction manual. 1.First measure the depth of the sump (L) and length of the column pipe (L2). This determines the dimension (L1) which must be above the minimum shown in the table below.

21 2. The anchor bolts should be pre-installed prior to concrete pour as part of the civil works. If this is not done then mark out and install the anchor bolts during the installation of the column pipe. 3. To install the column pipe a. Fit a waterproof membrane between the mounting flange and the concrete support structure. b. Slowly lower the column pipe into the sump using overhead lifting equipment. c. Confirm that column pipe is perpendicular and resting securely on the concrete surround. d. Last, tighten the nuts of anchor bolts ensuring pipe does not move. 4. To install the pump a. Slowly lower the pump into the column pipe using the overhead lifting equipment. Carefully guide the pump into position at the bottom of column pipe and rotation stoppers. The pump is secured by its own weight and the rotation stoppers. No additional fixing is required. b. Secure the cable to the cable holder. Route the cables through the cable gland and run the cables to the extend to electric junction box. Secure the cable in the cable gland with the O-ring and the bolts. c. Pull up the cable coming from stuffing box of pump up to the column pipe cover and keep it tighten up and tense in order not to be moved from side to side by discharging water. 5. Fit the column pipe cover on the upper part of column pipe using a waterproof gasket & tighten the bolts.

22 Rotate the propeller by hand in a clockwise direction as viewed from above (see figure) before installation. When starting the pump the motor torque will jerk the pump in the opposite direction to the propeller rotation. Exercise caution as the resulting jerk on large pump can be powerful. Check that the supply voltage and frequency agree with the specification on the pump name plate. If not, do not start the pump. Check that the outer sheathing on the cables is not damaged to ensure water cannot enter the junction box through the cable. If refitting the cable, cut off a short piece to ensure the cable entry sealing sleeve does not clamp around the cable at the same point again. Check that cable entry seal sealing and washers conform to the outside diameter of cable. When preparing power cable leads for connection to the pump and control panel, it is essential that the ground lead must have at least 50 mm slack remaining after connection. This is to ensure that if the cable is accidentally pulled out, the ground lead connection will be the last to be broken. Your pump is delivered connected for the voltage and frequency on the name plate and was factory prior to shipment under these conditions. 4. B EFORE STARTING

23 To minimize the risk of accidents and damage to the pump, all electrical work must be carried out by an electrician suitably qualified under local licensing laws. All local codes and health and safety rules must be followed. Before starting work on the pump, the power supply must be locked off or disconnected in such a way that it cannot be accidentally re-energized during the installation process. 5. E LECTRICAL WORKS Check of power cable insulation resistance After completion of the pump installation, check the insulation resistance of the primary and secondary power cables by measuring between each phase and earth using Mega tester. The result should be over 10MW. DO NOT test the wires of the protective device. Damage will result. Now measure the insulation resistance between phases as described overleaf for the appropriate starting method.

24 Direct on Line - Connect one of the three phase leads in the power cable to the to lead of the earth link of a Mega tester. - Measure the insulation resistance between the above phase and each of the other two phase leads. -If the insulation resistance is less than 1 MW in each case the connection is correct. Connect the motor than 1 MW there could be a partial open circuit or incorrect internal connection of the motor. In this case, do not connect the pump. Check the cable and motor connections, rectify and measure again before connecting. Star-Delta - Connect one of the six phase wires in the phase cable to the earth link of a Mega Tester. - Measure the insulation resistance between the above phase line and each of the remaining five phase wires. -Only one measurement should be 0 MW (closed circuit). If more than one measurement is 0 MW then there is a fault with the internal connection of the motor or the motor is damaged. -If the above test is passed connect the leads to the appropriate terminals in the control panel. When checking pumps wired Star-Delta to D.O.L or Reactor, Follow the table below. U, Z (1, 6) R V, X (2,4) S W,Y (3,5) T Reactor -Connect one of the six phase wires in the phase cable to the earth link of a Mega tester and test the wires in accordance with the same procedure as for star-delta -If this test is passed then the cables should be connected to the appropriate terminals in the control panel making sure to combine the wires from the pump in pairs of U & Z, V & X, and W & Y, which should then be connected to U, V and W in the panel respectively.

25 Grounding The earth wire (green color, labeled as E) must be connected to ground in the control panel. Verification that grounding continuity has been established must be confirmed by checking that the grounding wire is electrically conductive with a bolt on the motor (strip paint on bolt first).

26 Before staring work on the pump, make sure that the pump and control circuits are isolated from the power supply and cannot be energized. Make sure that the pump has been thoroughly cleaned from rubbish and sludge. In an established operation be aware of the risk of infection and follow the local health and safety regulation. 6. OPERATION Safety precautions Direction of propeller rotation Turn on the power and start the pump. The simplest check for correct rotation is the discharge of water from the discharge pipe. If not, check the current on the control panel ammeter. If it is low, it confirms that the pump is under loaded because the pump isnt pumping water due to the wrong rotational direction. To change the direction of rotation of the motor interchange the phases as shown in the diagram overleaf. Direct on line / Reactor starting Star-Delta

27 The Pump should be inspected at least twice a year, more frequently under severe operating conditions. Normally, the pump should be subjected to a major overhaul in a service shop every third year. This requires special tools and should be done by an authorized service shop. When the pump is new or when the seals have been replaced, inspection is recommended after one week of operation. Regular inspection and preventive maintenance ensure more reliable operation. 7. INSPECTION Recommendation inspection Inspectionremedy Visible parts on pump and installationReplace or fix worn and damaged parts. Make sure that all screws, bolts, and nuts are tight. Check the condition of carrying handle/lifting eyes, chains and wire rope Pump casing and propeller Replace worn parts if they impair function. Check clearance between the propeller and the wear rings. This should be not exceeded 2 mm (5/64 in). Liquid in motor casing WARNING, if there has been leakage through the seal, the oil chamber may under pressure, hold a rag over the inspection cover when unscrewing the screw to prevent splatter. Liquid in the motor casing If there is water in the stator casing, the cause may be: - That an O-ring (15-5, 50-5, 60-5) is damaged. - That the cable entry is leaking. If there is oil in the motor casing, the cause may be: - That the inner seal (25) is damaged. - That an O-ring (69-5) is damaged. Cable Entry Make sure that the cable clamps are tight If the cable entry leaks: - Check that the entry is tightened. - Cut off a piece of the cable, so that the sleeve closes around a new position on the cable. - Replace the seal sleeve. - Check that the seal sleeve and the washers conform to the outside diameter of the cables. Cables Replace the cable if the outer jacket is damaged. Make sure that the cables do not have any sharp bends and are not pinched. Starter EquipmentIf faulty, contact an electrician

28 Rotation direction of pumpTranspose two-phase leads if the impeller does not rotate clockwise Check the direction of rotation every time the pump is reconnected. Pipes, valves and other peripheral equipment Repair fault and notify supervisor of any faults or defects. Insulation resistance in the stator Use insulation resistance tester set on 100V-DC. Check phase to phase and phase to earth resistance. Test result should be in accordance with the values set out in section X Check of power cable insulation resistance according to the starting method of the pump. Storage Always lift the pump by its carrying handle of lifting eyes (lifting lugs), never by the motor cable or the hose. The pump is frost proof as long as it is operating or is immersed in the liquid. If the pump shall be operated for a short period after being taken up in order to expect all remaining water. Allowing the pump to stand immersed in the liquid for a short period before it is started can thaw a frozen propeller. Never use an open flame to thaw the pump. For longer periods of storage, the pump must be protected against moisture and heat. The propeller should be rotated by hand occasionally (for example every other month) to prevent the seals from sticking together or if the pump is submersed, operated it for 30 seconds. If the pump is stored for more than 6 months, this rotation is mandatory. After a long period of storage, the pump should be inspected before it is put into operation. Pay special attention to the seals and the cable entry. Clean the pump and spray with rust inhibiting oil, in addition to above, do not store in direct sun. Store in protected area. Changing the oil WARNING, if the primary mechanical seal leaks, the oil casing may under pressure. Cover the oil plug with a rag to prevent splatter whilst unscrewing. Completely pump out the used oil making sure that the removal tube goes all the way to the bottom of the casing. For complete drainage, the pump must be 60°. After refilling, tighten the oil plug. Replacing the wearing ring When clearance between the propeller skirt and the pump casing exceeds 2mm (5/64), the wearing ring must be replaced. Remove screw and lift the pump off the dell-mouth. Replace wearing ring. Assemble in opposite order

29 A universal instrument, a test lamp (continuity tester) and wiring diagram are required in order to carry out fault tracing on the electrical equipment. Fault tracing shall be done with the power supply isolated, except for those checks that cannot be performed without voltage. Always make sure that there is no one near the pump when it is connected. Use the following checklist as an aid to fault tracing. It is assumed that the pump and installation have formerly functioned satisfactorily. 8. TROUBLESHOOTING When pump fails to start Is a fault signal indicated on the panel ? Can the pump be Started manually ? Is a fault signal indicated on the starter? Contact Authorized Sever ice center Check the cause: - If the bearing temperature is high, take the pump to the shop for repair. -If the stator temperature is high, check that the cooling system is working and that the propeller rotates easily. -If there is a fault in thermal protectors, contact an authorized electrician. Check that the overload protection is reset. a) Fault in level equipment (start sensor) clean or replace. b) Fault in control panel. Check: - The control voltage is correct. Control fuse is OK. - That all connections are securely tightened. - That relay and contactor coils are functioning. -That the mode selector switch makes contact in each position. Check: - That the supply line voltage is correct on all phases. - That the main power switch is on, fuses intact. - That the overload protection is reset. -That there is no break in the motor cable.

30 When pump starts but stops on motor protection Is the motor protection set too low ? (Check with motor data name plate) Adjust Clean the propeller or clean out the sump Contact an authorized electrician Use an insulation tester set to 1000 V-DC, check insulation between phases and between phases and earth (ground) complies with the correct levels for the type of motor starting. Contact an authorized electrician Dilute the liquid Replace defective motor protection devices Is the propeller difficult to rotate by hand ? Is the installation receiving full voltage on all three phase ? Are the phase currents unbalance or too high ? Is the insulation between the phases and earth in the stator defective ? Is the density of the pumped liquid too high? (Max. density 70 lb/ft3) Fault in motor protection devices Contact Authorized service center

31 When pump does not stop Is the pump able to empty the sump to stop level ? Check: - For leakage in pipe discharge connection - That the propeller is not clogged -The valves are open. Clean the stop sensor Check the contactor and holding circuit Replace defective items Raise the stop level Fault in level sensing g equipment Stop level is set too low Contact Authorized service center Does the pump start due to backflow, Which fills sump to the start level again? Does the contractors self-holding function fail ? Contact Authorized service center When starts-stops-starts in rapid sequence Check: - That distance between the start and stop level is not to small - The valves (if any) -Function of non return valve Check - Contactor connection - The voltage in the holding circuit in relation to the rated voltage on the coil.

32 The recommendations given in this section are intended as a guide only. JMI accepts no responsibility for the incorrect design of the civil works whether or not it is based on these recommendations and dimensions. The provision of a correct & successful design is the responsibility of the project designer. 8. DESING OF SUBMERSIBLE PROPELLER PUMP STATION Recommended sump dimensions The design of the pumping station should aim at positioning the pumps and dividing walls, so as to avoid creating adverse phenomena, such as surface vortices, air ingestion and entrainment, large scale turbulence and a fully developed air core which result from poor sump design and adversely affect performance. The following factors need to be considered in the sump design. - The velocity & distribution of the fluid in the approach channel to the sump should be symmetrical. - The effects of flow disturbances should be dissipated as far as possible from the pump intakes. - Stagnation regions should be avoided in design or post design by filling with concrete. - The maximum velocity of the upstream fluid in the approach channel to the sumps should be 0.3 ~ 0.5 m/sec. - Vortex shedding should be minimized. In consideration of the above points recommended dimensions for approach channels are as shown overleaf..

33 Arrangement of a single pump sump To properly position a single pump, the pumps approach channel should be in line with the station inlet channel. The transition from the station inlet to the sump floor beneath the pump should be as possible to avoid air entrainment and turbulence. The preferred gradient is maximum 15°. Arrangement of a multiple pump sump The same design principles for single pump systems are also applicable to multiple pumps. In addition the uniform flow between each pump must be established by diving walls between adjacent pumps. Each individual sump should be dimensioned as for a single pump installation. In order to ensure a uniform flow on all pumps, a sudden expansion of the station inlet must be avoided. The preferable transition diffuser angle is 20° maximum.


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