KRAL C Series Operating Instructions Manual
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Summary of Contents for KRAL C Series
- Page 1 Operating instructions KRAL screw pumps. Series C / Type CGF/CGH/CGV/CLE Mechanical seal/Radial shaft seal OIC 18en-GB Edition 2020-01 Original instructions www.kral.at...
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Page 2: Table Of Contents
Table of contents 1 About this document ............. 4 Connecting the pump unit to the power supply .... 22 General information ............ 4 10 Operation................ 22 Associated documents .......... 4 10.1 Dangers during operation .......... 22 Target groups .............. 4 10.2 Commissioning ............ 22 Symbols................. 4 10.2.1 Cleaning the pipe system ........ 22 1.4.1 Danger levels ............ 4... - Page 3 Table of contents 14.1 Possible faults ............. 49 14.2 Troubleshooting............ 49 15 Accessories .............. 52 15.1 Heating ................ 52 15.1.1 Possible types of heating ........ 52 15.1.2 Fluid heating system ........ 52 15.2 Overflow valve ............. 54 15.2.1 Adjusting the overflow valve ...... 55 16 Spare parts .............. 56 16.1 Overview of CLE 15 – 660, CLE 880 (inner bearing) .. 56 16.2 Overview of CLE 851, CLE 951 – 3550 (inner bearing) .................. 57...
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Page 4: About This Document
1 About this document 1.1 General information 1 About this document 1.1 General information These instructions form part of the product and must be kept for future reference. Furthermore please observe the associated documents. 1.2 Associated documents o Declaration of conformity according to EU Directive 2006/42/EC o Manufacturer's declaration according to EU Directive 2014/68/EU o Data sheet of the pump o Technical documentation of the supplied components... -
Page 5: Danger Signs
2 Safety 2.1 Proper use 1.4.2 Danger signs Meaning Source and possible consequences of non-observance Electrical voltage Electrical voltage causes serious physical injury or death. Raised load Falling objects can result in serious physical injury or death. Heavy load Heavy loads can result in serious back problems. Risk of slipping Discharging pumped liquid and oils on the foundation or tread sur- faces can cause falls with serious physical injury or death. -
Page 6: Obligations Of The Operator-Owner
3 Identification 2.3 Obligations of the operator-owner 2.3 Obligations of the operator-owner The operator-owner is the person who operates the product commercially or permits a third party to use it and who bears the legal responsibility for the product, the protection of the personnel and third parties during its operation. - Page 7 3 Identification 3.1 Type code Item Classification Description Shaft seal Standard mechanical seal Mechanical seal of hard material Standard radial shaft seal Magnetic coupling Mechanical seal with quench Shaft seal PTFE with quench High-pressure radial shaft seal Mechanical seal balanced Stuffing box packing Mechanical seal with throttle ring Special design...
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Page 8: Rating Plate
ºC ¹ Serial number max. / p max. mm²/s Type Jahr | Year Gewicht | Weight KRAL GmbH, 6890 Lustenau, Austria KRAL GmbH, 6890 Lustenau, Austria www.kral.at www.kral.at Article number Fig. 2: Rating plate Differential pressure Nominal delivery rate Rated speed... -
Page 9: Required Npsh Values
The required NPSH values of the pump depend on the size, the viscosity of the pumped liquid and the speed. The NPSH values are available on the website of the manufacturer: www.kral.at/en/screw-pumps 4.3 Sound pressure level Guide values at 1 m distance, 1450 min... -
Page 10: Function Description
5 Function description 5.1 Cartridge pump structure 5 Function description 5.1 Cartridge pump structure Fig. 3: CLE 15 – 660, CLE 880 structure, inner bearing Fig. 4: CLE 851, CLE 951 – 3550 structure, inner bearing Operating instructions OIC 18en-GB Edition 2020-01... - Page 11 5 Function description 5.1 Cartridge pump structure Fig. 5: CLE 32 – 660, CLE 880 structure, outer bearing 5 10 Fig. 6: Structure CLE 851, CLE 951 – 3550, outer bearing Main screw Shaft seal (mechanical seal) Idle screw Seal housing Cartridge housing Bearing bush Flange cover Counter-pressure valve Balancing cylinder Seal flange Ball bearing Operating instructions...
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Page 12: Pump Unit Structure
5 Function description 5.2 Pump unit structure 5.2 Pump unit structure Fig. 7: Pump unit structure Outer housing Coupling intermediate ring Cartridge pump Motor-side coupling half Overflow valve (optional) Motor Pump bracket Pump bracket foot Pump-side coupling half 5.3 Functional principle Screw pumps are rotating pumps. -
Page 13: Shaft Seal
5 Function description 5.5 Shaft seal For the steel material housing variant all flow directions can be realized through different positioning of the flange connections. Fig. 9: Housing variants of flange connection 5.5 Shaft seal The following types of shaft seals are offered: o Mechanical seal standard or hard material o Mechanical seal with quench o Mechanical seal with throttle ring... -
Page 14: Seal Variants Outer Bearing
5 Function description 5.6 Overflow valve (optional) Radial shaft seal standard/high-temperature Depending on the material used, radial shaft seals can be used for temperatures of up to Radial shaft seal ring 150 °C (standard) or 90 °C (high pressure) re- Ball bearing spectively. -
Page 15: Transportation, Storage
6 Transportation, storage 6.1 Dangers during transportation 6 Transportation, storage 6.1 Dangers during transportation The following safety instructions must be observed: o Have all work only carried out by authorized transport personnel. o Use intact and correctly dimensioned hoisting equipment. o Ensure that the means of transport is in a flawless state. -
Page 16: Storing The Pump
7 Preservation 6.5 Storing the pump Fig. 10: Fastening of hoisting equipment - principle diagrams Attach the hoisting equipment to the pump/pump unit and tighten. Ensure that the centre of grav- ity lies exactly under the crane hook. Lift the pump/pump unit carefully and put it down shock-free. Before loosening the transport belts ensure that the pump/pump unit is secured against tilting. -
Page 17: Preserving The Inner Surfaces
7 Preservation 7.2 Preserving the inner surfaces 7.2 Preserving the inner surfaces o Trained personnel Personnel qualification: o Work clothing Personal protective equipment: o Protective gloves o Safety boots Aids: o Preservative (acid-free and resin-free oil) Open the packaging carefully. If the pump is protected additionally by anti-corrosion paper, en- sure that it is not damaged. -
Page 18: Installation, Removal
8 Installation, removal 8.1 Dangers during installation 8 Installation, removal 8.1 Dangers during installation The following safety instructions must be observed strictly: o Have all work carried out only by authorized qualified personnel. o Before installation ensure that the operating limits, NPSH values and ambient conditions are ob- served. -
Page 19: Removing The Pump
8 Installation, removal 8.4 Removing the pump Pressure connection Suction connection Fig. 11: Flow direction Requirement: ü Pump connections protected against soiling, for example by using the protective cover mounted in the factory ü If required, hoisting equipment prepared Bring the pump in the installation position, while observing the position of the motor and the ar- rows for the flow direction on the pump housing (1 pressure connection, 2 suction connection). -
Page 20: Connection
9 Connection 9.1 Dangers during connection work Screw out the fastening elements used to fasten the pump. Dismantle the pump unit on site or transport it to a suitable location Ä Transportation, stor- age, Page 15. 9 Connection 9.1 Dangers during connection work The following safety instructions must be observed strictly: o Have all work on the pump and pipe system only carried out by authorized qualified personnel. -
Page 21: Insulating The Pump
9 Connection 9.3 Insulating the pump 9.3 Insulating the pump o Fitter Personnel qualification: o Work clothing Personal protective equipment: o Protective gloves o Safety boots Aids: o Insulation material WARNING Hot surface. Touching of uninsulated hot surfaces results in burns. ►... -
Page 22: Connecting The Pump Unit To The Power Supply
10 Operation 9.5 Connecting the pump unit to the power supply Check the radial displacement ΔKr of the coupling using a hairline gauge and feeler gauge. Check several points along the periphery of the coupling. Check the angular displacement ΔKw of the coupling using a hairline gauge. Check the axial displacement ΔKa of the coupling using a slide gauge or feeler gauge. -
Page 23: Filling And Venting The Pump
10 Operation 10.2 Commissioning ATTENTION Damage to equipment through additional pressure loss in the commissioning filter/commis- sioning strainer. ► Calculate the flow resistance and determine the remaining pump intake. ► Monitor the suction-side pressure. ► Check the commissioning filter/commissioning strainer regularly. Requirement: ü... -
Page 24: Checking The Direction Of Rotation
10 Operation 10.2 Commissioning Open the screw plug of the vent hole 1 by a max. of 2 rotations so that air can escape during the filling process. Open the suction-side or pressure-side shut-off device and fill the pump via the suction connec- tion or pressure connection until pumped liquid is emitted at the vent hole 1. -
Page 25: Commissioning The Pump
10 Operation 10.2 Commissioning Compare the direction of rotation of the fan impeller with the arrow indicating the direction of rotation 1. If the directions do not match, swap the two electrical connection phases. Repeat Steps 1 and 2. 10.2.4 Commissioning the pump Personnel qualification: o Fitter o Electrician... -
Page 26: During Operation
10 Operation 10.3 During operation Requirement: ü Pump unit set up correctly ü Coupling aligned correctly Ä Connection, Page 20 ü Connections connected sealingly ü Motor connected correctly ü Pipe system is free of impurities ü Safety valve in accordance with EN ISO 4126-1 installed in the pressure-side pipe system before the first shut-off device ü... -
Page 27: Decommissioning
10 Operation 10.4 Decommissioning ATTENTION Damage to seal through pressurizing during standstill. ► Ensure that the maximum permissible system pressure is not exceeded. Switch off the motor. Close the pressure-side shut-off device. 10.4 Decommissioning 10.4.1 Decommissioning the pump Decommissioning is an operation interruption that requires different measures depending on the scope of duration and the interruption as well as the properties of the pumped liquid. -
Page 28: Recommissioning
11 Maintenance 10.5 Recommissioning Behaviour of the pumped liquid Duration of the operation interruption Short Long o Solids sediment Rinse the pump. Rinse the pump. o Congealed/frozen Heat or drain the pump. Drain the pump. o No corrosive burden o Congealed/frozen Heat or drain the pump. -
Page 29: Ball Bearing (Outer Bearing)
11 Maintenance 11.4 Ball bearing (outer bearing) 11.4 Ball bearing (outer bearing) The ball bearings used are lifetime lubricated. Maintenance is therefore not required. The manufacturer recommends renewing the ball bearings every 20,000 operating hours. 11.5 Maintaining the pump Personnel qualification: o Fitter o Work clothing Personal protective equipment:... -
Page 30: Servicing
12 Servicing 12.1 Dangers during servicing 12 Servicing 12.1 Dangers during servicing The following safety instructions must be observed strictly: o Have all work carried out only by authorized qualified personnel. o Before beginning work on the pump ensure that the electrical power supply is deenergized and is secured against being switched back on. -
Page 31: Installing The Coupling
12 Servicing 12.3 Replacing the coupling WARNING Risk of injury and damage to equipment through falling and toppling parts. ► Use intact and correctly dimensioned hoisting equipment in accordance with the total weight to be transported. ► Select the lift points for the hoisting equipment in accordance with the centre of gravity and the weight distribution. -
Page 32: Replacing The Mechanical Seal (Inner Bearing)
12 Servicing 12.4 Replacing the mechanical seal (inner bearing) Ensure that the fixing screw 11 of the pump-side coupling half 10 is loosened. Slide the pump-side coupling half onto the shaft until it stops and tighten the fixing screw. Tighten the socket screws 9 between the pump 2 and pump bracket 3 with torque. Measure and write down the distance X between the face of the coupling claws and the fitting surface of the pump bracket. - Page 33 12 Servicing 12.4 Replacing the mechanical seal (inner bearing) Remove the feather key 5 of the main screw 1. Size 15 – 660, 880 (figure left): Remove the socket screws 4 of the seal housing 3 and take off the seal housing. -or- Size 851, 951 – 3550 (figure right): Remove the socket screws 4 of the seal flange 10 and take off the seal flange.
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Page 34: Installing The Mechanical Seal
12 Servicing 12.4 Replacing the mechanical seal (inner bearing) Mechanical seal standard/with throttle ring/with quench: (figure left): Remove the rotary seal ring 16 from the main screw 1. -or- Mechanical seal hard material (figure right): Loosen the fixing screws 17 of the mechanical seal (quantity depends on size). Remove the rotary seal ring 16 from the main screw 1. - Page 35 12 Servicing 12.4 Replacing the mechanical seal (inner bearing) Mechanical seal with throttle ring Size 15 – 660, 880: Use the mounting arbour radial shaft seal ring E to press the throttle ring 14 into the seal hous- ing 3 and insert the circlip 13. Use the mounting arbour stationary seal ring A to press the stationary seal ring 12 with mounted O-ring into the seal housing.
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Page 36: Replacing The Radial Shaft Seal (Inner Bearing)
12 Servicing 12.5 Replacing the radial shaft seal (inner bearing) 12.5 Replacing the radial shaft seal (inner bearing) 12.5.1 Removing the radial shaft seal Personnel qualification: o Fitter o Work clothing Personal protective equipment: o Protective gloves o Safety boots o Tool set, radial shaft seal Ä... -
Page 37: Installing The Radial Shaft Seal
12 Servicing 12.5 Replacing the radial shaft seal (inner bearing) 12.5.2 Installing the radial shaft seal Personnel qualification: o Fitter o Work clothing Personal protective equipment: o Protective gloves o Safety boots o Tool set, radial shaft seal Ä Spare parts, Page 56 Aids: o Thread sealant (for example Loctite 572) o Molybdenum disulphide paste (for example Fenkart T4) -
Page 38: Replacing The Ball Bearing And Screw Set (Inner Bearing)
12 Servicing 12.6 Replacing the ball bearing and screw set (inner bearing) Attention: Take the mounting direction of both radial shaft seal rings 15 into account. Supporting rings 14 of the radial shaft seal can be positioned differently. Use the mounting arbour to carefully press the components of the radial shaft seal into the seal housing in accordance with the sectional view (radial shaft seal ring 15 (2x), supporting ring 14 (2x), distance ring 16 (2x)). -
Page 39: Installing The Ball Bearing And Screw Set
12 Servicing 12.6 Replacing the ball bearing and screw set (inner bearing) Clamp the pump at the main screw. Ensure that the shaft is not damaged in the process. Size 15 – 660, 880 (figure left): Remove the socket screws 6 at the flange cover 5. Size 851, 951 – 3550 (figure right): Remove the socket screws 7 at the flange cover 5. - Page 40 12 Servicing 12.6 Replacing the ball bearing and screw set (inner bearing) Size 15 – 660, 880: Press the balancing cylinder 12 onto the shaft of the main screw 2. Press on the ball bearing 13. Slide the supporting ring 14 onto the main screw and mount the circlip 15. Unclamp the main screw, rotate it by 180°...
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Page 41: Replacing The Mechanical Seal And Ball Bearing (Outer Bearing)
12 Servicing 12.7 Replacing the mechanical seal and ball bearing (outer bearing) Place the idle screws left and right of the main screw so that the fitting surfaces of the bearing bushes contact the shaft of the main screw. Observe the alignment of the positioning pins 16. Attention: Ensure that the adapter sleeve 18/straight pin 19 is not damaged when mounting the cartridge housing. - Page 42 12 Servicing 12.7 Replacing the mechanical seal and ball bearing (outer bearing) Size 32 – 42: Remove the circlip 23 and supporting ring 22 from the main screw. -or- Size 160 – 660, 880: Remove the groove nut 6, locking plate 5 and distance ring 4 from the main screw. -or- Size 851, 951 – 3550: Remove the circlip 25 and distance sleeve 24 from the main screw.
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Page 43: Installing The Mechanical Seal And Ball Bearing
12 Servicing 12.7 Replacing the mechanical seal and ball bearing (outer bearing) 12.7.2 Installing the mechanical seal and ball bearing Personnel qualification: o Fitter o Work clothing Personal protective equipment: o Protective gloves o Safety boots o Tool set, mechanical seal Ä Spare parts, Page 56 Aids: o Silicone grease Clean the main screw 1 carefully in the area of the mechanical seal and grease it. -
Page 44: Replacing The Screw Set (Outer Bearing)
12 Servicing 12.8 Replacing the screw set (outer bearing) Attention: Ensure that the spring ring is not damaged while mounting the seal housing. Take the holes in the pump flange into account. Carefully slide the seal housing with flat gasket until the pump flange stops at the main screw. Remove the mounting sleeve main screw B. -
Page 45: Installing The Screw Set
12 Servicing 12.8 Replacing the screw set (outer bearing) Size 32 – 42, 55 – 660, 880 (figure left): Remove the socket screws 6 at the flange cover 5. Size 2250 – 3550 (figure right): Remove the socket screws 7 at the flange cover 5. Lift the cartridge housing 1 of the flange cover. Hold the idle screws 3 in the process. Remove the idle screws. - Page 46 12 Servicing 12.8 Replacing the screw set (outer bearing) Clean the fitting surfaces carefully, position the flat gasket 11 in the flange cover. Size 32 – 42, 55 – 660, 880, 2250 – 3550: Position the edge sealing rings 8 in the flange cover. Take the recesses for the edge sealing rings into account. Mount the bearing bush set 9, consisting of the bearing bush and segment washer (segment washer only for Size 32 – 42, 55 – 660, 880), on the shafts of the idle screws 3.
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Page 47: Replacing The Cartridge Pump
12 Servicing 12.9 Replacing the cartridge pump 12.9 Replacing the cartridge pump 12.9.1 Removing the cartridge pump o Fitter Personnel qualification: Personal protective equipment: o Work clothing o Protective gloves o Safety boots o Mounting lever Aids: o Hoisting equipment WARNING Risk of injury and damage to equipment through falling and toppling parts. -
Page 48: Disposal
13 Disposal 13.1 Dismantling and disposing of the pump WARNING Risk of injury and damage to equipment through falling and toppling parts. ► Use intact and correctly dimensioned hoisting equipment in accordance with the total weight to be transported. ► Select the lift points for the hoisting equipment in accordance with the centre of gravity and the weight distribution. -
Page 49: Troubleshooting
14 Troubleshooting 14.1 Possible faults WARNING Danger of poisoning and environmental damage through residues. ► Wear personal protective clothing during all the work. Ensure face protection. ► Before disposal collect any pumped liquid still present safely and dispose of it in an environment- ally compatible manner in accordance with the applicable local regulations. - Page 50 14 Troubleshooting 14.2 Troubleshooting Fault identification Cause Remedy 1 – – – – – – Too little pumped liquid in the pump Fill the pump with pumped liquid. 1 – – – – – – Incorrect pump direction of rotation Swop the two electrical connection phases Ä...
- Page 51 14 Troubleshooting 14.2 Troubleshooting Fault identification Cause Remedy – – – – – – 7 Inlet pressure too high Reduce the inlet pressure at the system side. Replace the shaft seal Ä Servicing, Page 30. – – – – – – 7 Inlet pressure too low Install a non-return valve at the pressure side.
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Page 52: Accessories
15 Accessories 15.1 Heating 15 Accessories 15.1 Heating 15.1.1 Possible types of heating The pump can optionally be equipped with a heating system. The manufacturer recommends a heating system at high-viscosity pumped liquids that do not flow sufficiently if not heated. A flowability that lies too low can result in excessive power draw or to cavitation or sealing problems. - Page 53 15 Accessories 15.1 Heating Pump with outer housing GJS Size Dimensions [mm] Steam amount [kg/h] 15 – 26 R 1/4" 32 – 42 R 1/4" 55 – 85 R 1/4" 105 – 118 R 1/4" 160 – 210 R 1/4" 235 – 275 R 3/8" 370 – 450 R 3/8" 550 – 880 R 3/8" 851 – 951 R 3/8"...
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Page 54: Overflow Valve
15 Accessories 15.2 Overflow valve Installing the fluid heating system Personnel qualification: o Fitter o Work clothing Personal protective equipment: o Protective gloves o Safety boots 915.8 Requirement: ü Pump unit disconnected from the electrical power supply, deenergized and secured against being switched back on 739.8 739.7... -
Page 55: Adjusting The Overflow Valve
15 Accessories 15.2 Overflow valve It therefore has to be ensured through a safety valve at the system that the maximum operating pres- sure always lies under the opening pressure of the overflow valve. The overflow valve is offered as a circulation valve (figure left) or as a non-return valve (figure right). Notice o A function test of the overflow valve at least every 5 years is essential for the safe operation Ä... -
Page 56: Spare Parts
16 Spare parts 16.1 Overview of CLE 15 – 660, CLE 880 (inner bearing) 16 Spare parts 16.1 Overview of CLE 15 – 660, CLE 880 (inner bearing) 745.1 222.1 745.1 869.2 859.1° 056.1 056.1 056.2 915.1 735* 661.1 056.3 869.2 859.3 745.2 859.2 056.3 222.2 428** 915.2 661.2 739.1 739.2... -
Page 57: Overview Of Cle 851, Cle 951 - 3550 (Inner Bearing)
16 Spare parts 16.2 Overview of CLE 851, CLE 951 – 3550 (inner bearing) 16.2 Overview of CLE 851, CLE 951 – 3550 (inner bearing) 884° 097 222.1 056.1 222.3* 915.3 869.2 054 056.1 739.3 056.2 915.1 661.1 869.1 879.2 739.1 879.1 661.2 915.2 739.2 454* 222.2 1037 Fig. 18: Spare parts CLE 851, CLE 951 – 3550 Qty. -
Page 58: Overview Of Cle 32 - 42, 55 - 660, Cle 880 (Outer Bearing)
16 Spare parts 16.3 Overview of CLE 32 – 42, 55 – 660, CLE 880 (outer bearing) 16.3 Overview of CLE 32 – 42, 55 – 660, CLE 880 (outer bearing) 056.1* 869.3* 222.1 859.1 056.2 739.3**** 056.3 306** 054** 464*** 307** 915.1 661.1 428° 869.1 869.2 859.3 056.3 739.1 222.2 915.2 661.2 739.2 859.2 1037 Fig. 19: Spare parts CLE 32-42, 55-660, CLE 880... -
Page 59: Overview Of Cle 851, Cle 951 - 3550 (Outer Bearing)
16 Spare parts 16.4 Overview of CLE 851, CLE 951 – 3550 (outer bearing) 16.4 Overview of CLE 851, CLE 951 – 3550 (outer bearing) 056.1*** 222.1 868** 056.2 661.1 915.1 428° 879.1 879.2 661.2 915.2 739.1 739.2 454* 222.2 1037 Fig. 20: Spare parts CLE 851, CLE 951-3550 Qty. -
Page 60: Overview Of Outer Housing Gjs Cgf/Cgh/Cgv
16 Spare parts 16.5 Overview of outer housing GJS CGF/CGH/CGV 16.5 Overview of outer housing GJS CGF/CGH/CGV 915.8 540.2 739.7 739.8 915.7 540.1 739.8 739.7 739.7 739.8 540.2 915.9 915.8 915.10 915.8 Fig. 21: Spare parts outer housing GJS Qty. Item No. Part Qty. -
Page 61: Overview Of Accessories Cgf/Cgh/Cgv
16 Spare parts 16.7 Overview of accessories CGF/CGH/CGV 16.7 Overview of accessories CGF/CGH/CGV 915.8 739.8 739.7 739.10 915.9 Fig. 23: Spare parts accessories Qty. Item No. Part Qty. Item No. Part End cover 739.8 O-ring Flat gasket 739.10 O-ring Overflow valve 4/6/8 915.8 Socket screw Fluid heating system... -
Page 62: Tool Set, Radial Shaft Seal
17 Appendix 17.1 Tightening torques for screws with metric screw threads with and without wedge lock washers 16.8.2 Tool set, radial shaft seal Qty. Part Mounting arbour radial shaft seal ring Mounting sleeve main screw Mounting sleeve ball bearing 17 Appendix 17.1 Tightening torques for screws with metric screw threads with and without wedge lock washers Notice In the case of galvanised screw plugs and screw plugs made of stainless steel the inner thread and... -
Page 63: Tightening Torques For Screw Plugs With Thread Measured In Inches And Elastomer Seal
17 Appendix 17.2 Tightening torques for screw plugs with thread measured in inches and elastomer seal 17.2 Tightening torques for screw plugs with thread measured in inches and elastomer seal Notice In the case of galvanised screw plugs and screw plugs made of stainless steel the inner thread and outer thread have to be greased thorough before mounting in order to prevent threads from seizing. - Page 64 KRAL GmbH, 6890 Lustenau, Austria, Tel.: +43/5577/86644-0, E-Mail: kral@kral.at www.kral.at...
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