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English to Serbian: Bill of materials General field: Tech/Engineering Detailed field: Electronics / Elect Eng
Source text - English 4.5. Determine the right location of the levelling elements (Fig. 1) and put them in place. Fix in place the levelling elements using preferably a bonding agent like Sikadur or similar. Put the machine with the bedplates on the levelling elements and adjust the level. The machine axis position must be approximately in accordance with the indication of the machine outline drawing.
4.6. Exactly align the motor to the coupling half of the mating machine by sliding it horizontally and adjusting vertically by means of the levelling screw.
5. Grouting guidelines
Site management is responsible for ensuring that the work is carried out in a proper and professional manner. Foundation and fastening components must be absolutely clean and unpainted. Never grout in parts which are oily or have been coated with normal paint.
5.1. Grouting in the foundation bolts (Fig. 2). Check again that the foundation surfaces is clean and wet. Fill the holes for foundation anchor bolts with thin-bodied concrete up to approximately 10 mm below the top edge and vibrate if possible. Minimum setting time is 72 hours. After this period of time, the fastening nuts (16) may be tightened up (move the motor if necessary). Care has to be taken when tightening up that neither the machine housing nor the sole plates or bedplated are distorted. After tightening, check again shaft alignment and correct if necessary.
5.2. Grouting in the foundation through-bolts (Fig. 3). If foundation through-bolts are provided fit anchor plates (8) and tighten up bolts. Care has to be taken when tightening up that neither the machine housing nor the sole plates or bedplated are distorted. After tightening, check again shaft alignment and correct if necessary. Dry foundation holes for bolts (6) and pack out with elastic filler (13) to 5-10 mm below top edge. ABB recommend a granular synthetic filling compound, e.g. LUSTREX-Polystyrene 2220 or 4220. Supplier: MONSANTO PLASTICS & RESINS CO. 800 N. Lindbergh Blvd., St. Louis, No. 63166 (USA). Sand may not be used as a filler. After packing out with filler (13), seal top of foundation holes with an oil-resistive elastic sealing compound (14), e.g. with Sikaflex - 11 FC.
5.3. Finish grouting foundation in conformity with the corresponding outline drawing and foundation plan. Vibrate enclosed concrete (12). Cast foundation plinth as close as possible to finished size (5-10 mm below top face of sole plate). Take care that the sole plates are completely filled with grout, tamping if necessary. (Mixture, pt. 5.5).
5.4. Using concrete from a ready-mix concrete company subjected to quality control reduces risks in quality and should be procured if available. As a basic rule, higher standards of quality are to be set when ordering smaller quantities. One should try to attain a concrete strength B25 = 25 N/mm2.
If the services of a ready–mix concrete company are not available and in the absence of concrete mixture ratios, the figures given below may be taken as a guide.
5.5. The concrete mixtures P300 and P350 are suitable for grouting machine foundations and contain 300 kg and 350 kg cement per 1 m3 of concrete, respectively. The sand and gravel proportions for 1 m3 of finished concrete (1.2 m3 mixture) are as follows:
40% Fine sand Grain size 0-5 mm
25% Coarse sand Grain size 6-15 mm
35% Gravel Grain size 16-35 mm
100-110 litres of water
The following mixture can be used for grouting the anchor bolt holes:
2/3 Fine sand Grain size 0-5 mm
1/3 Coarse sand Grain size 6-15 mm
When using any other mixtures, always cast and test a specimen block. Only clean, washed materials must be used.
A high concrete strength will be attained with high standard strength of the cement, low water-cement ratio, and compacting by vibrating.
Water contents (I)
Water-cement ratio = --------------------------------
Cement contents (kg)
The water-cement ratio has a decisive influence on the final strength of the concrete. It is desirable to have a water-cement ratio of 0.3 to 0.45, whereby the water contents of the aggregates must be taken into consideration. It is not permitted to have a water-cement ratio > 0.6.
The concrete shall neither dry out nor freeze during the first 48 hours. During this time the temperature of the foundation should not fall below 10°C. The optimum temperature for the setting process is 20°C ± 10°C. Under normal conditions the foundation can be statically loaded 3 days after casting.
6. Mounting the machine on separately prepared steel base.
In this case it is supposed that the steel frame (already properly fixed to the floor) is correctly aligned with the mating machine.
Check the thread for inserting the fastening bolts and set down the motor. Align the motor with the levelling screws and the shims than tighten the bolts.
7. Test before coupling.
A test run is suggested before the coupling halves of the joint to the mating machine is connected. Refer to the commissioning instruction.
Levelling spindle
Sole plates/Bedplate with foundation anchor bolts
Sole plates/Bedplate with foundation through-bolt
Fig. 3
Mounting arrangement
The general rules for foundation and mountings are similar to the rules for horizontal mounting arrangement. See Sheet No DMPB 6182 E. In general vertical machine are mounted on a separately prepared steel foundation plate.
Installation on a steel foundation plate
Check fastening holes in steel foundation plate, clean seating surfaces, set down machine and align.
Couple machine and bolt up in operating location. Tighten holding down bolts uniformly, working in opposite pairs.
The machine must rest squarely on its fastening flange around the whole circumference.
After the final checks dowel the motor on the steel plate.
1. Machine fastening flange
2. Steel foundation plate
3. Holding down bolt
Preliminary inspection
Inspection of all functional parts and components is essential before fitting a coupling for the first time. The hub bore and shaft extension should be checked against the dimensions specified on the sketch or drawing.
It should also be ensured that the keyways in the coupling and shaft extension are truly parallel.
The machine rotor is balanced with a half-key. Coupling components should be balanced on a mandrel, with a half-key filling the keyway.
General information
The following are the most frequent causes of poorly seated coupling hubs:
- Damage on the shaft, coupling or keyway (indentations, burrs or pressure marks).
- Non-parallelism of keyways causing jamming and excessive lateral thrust on keys and keyways.
- Key too high causing it to bear top load.
- A key fitted in a tapered shaft extension affects the function of the tapered shrink seat and should therefore be avoided. If a key is nevertheless fitted, the coupling seat must be more accurate than normal. This means not only maintaining all tolerances but also that the exact contact between shaft and hub mating surfaces must be verified with blue oil, keyways in both shaft and hub must be checked for absolute parallelism, and the slightest imperfections such as burrs or pressure marks must be absolutely avoided.
Fitting instructions
Thoroughly clean and dry all mating surfaces. Never coat such surfaces with molybdenum disulphide (Molykote) or similar products. A thin coating of oil on the shaft extension and hub bore is to be recommended.
In general, the coupling manufacturer’s instructions are valid for mounting and removing the coupling hubs.
It is common practice to heat the coupling in order to increase (or make) the clearance between the two fitting parts. If the coupling is keyed there is a certain clearance between the coupling and the shaft extension, so heating the coupling up to 80°C (176°F) will be sufficient for an easy fitting.
Cylindrical and conical couplings (without keyway) are always fitted with interference and must be heated for the assembling on the shaft end. Refer to the specific instruction of the manufacturer.
IMPORTANT! : the couplings assembled with interference must be “enlarged” in case of disassembling from the shaft end. The enlargement is usually obtained by injection of oil under high pressure in circumferential grooves connected to suitable small oil injection channels.
It is very important to take care, during the coupling assembling, to avoid any incision or axial scratch, that would prevent the oil pressurisation. Remember that if the oil can’t be pressurised, the coupling removal become very difficult, and in some case impossible.
The weight of a coupling hub can be considerable, therefore suitable lifting gear must be available.
Axial clearance
The values for permissible axial loading are given on the machine dimension drawing. The axial clearance in the coupling must be chosen large enough to accept shaft displacement from the coupled machine. Our machines are normally fitted with a guide bearing at the drive end. Thermal expansion can therefore act towards the non-drive end without loading the coupling.
Disassembling instruction
Removal of couplings with keyway.
The removal of the coupling from the shaft end can be easily obtained with a pulling tool of suitable dimension. Remember to protect the shaft end, where there is the contact with the pulling device centre pivot, with suitable soft material (see point A).
Removal of couplings fitted with interference.
In this case a suitable device for injecting oil under high pressure (in the order of 1000 bar and more) is required, together with an hydraulic jack capable of generating a force in the order of 100 ton.
The detailed instruction for the whole operation are generally described in the instruction manual of the coupling, so we suggest to refer to this document.
The main steps of the operation are here described for information.
The dismantling operation of a coupling provided for cylindrical shaft end consists mainly of the following steps:
- Place the hydraulic jack between the shaft end and the coupling (through suitable plate and rods) to exert an axial force between the shaft end and the inner surface of the coupling. In other words the force generated with the jack must push the coupling out of the shaft end.
- Sustain with a suitable crane the weight of the coupling to avoid that the coupling will load the shaft end and the fall of the coupling itself.
- Connect the high pressure device at the threaded hole provided for this purpose on the coupling.
- Inject the oil under pressure into the circumferential grooves of the coupling and rise the pressure of the oil, following the operational instructions, to the value indicated on the instruction manual. If the whole system is without oil leakages, the coupling diameter will gradually expand, and the oil will come out laterally after some time (about 15 minutes).
- Apply with the hydraulic jack the axial force between the coupling and the shaft end. The force required for the extraction is normally in the order of 50 tons.
- Take off the coupling in one continuos step, possibly without interruption, maintaining a constant pressure on the oil.
In case of coupling with two or more inner diameter refer carefully to the detailed instructions of the manufacturer.
INSTRUCTION FOR ALIGNING COUPLINGS
The aim of the instruction given in the following is to attain proper alignment of the shaft extension without angular or parallel mismatch. This requirement can be fulfilled, as far as practically possible, by careful and accurate workmanship. The alignment instructions are basically valid for both rigid and flexible couplings and for all kinds of driven equipment.
As well known, the linear dimension of the metallic objects changes with the temperature. Therefore during the alignment at ambient temperature, the evaluation of the rotation centerline position at the working temperature is suggested so it can be decided how much radial displacement is to be set for the cold machine in order to have the ideal condition of zero misalignment at the expected operating temperatures.
For steel structures, like the motor frame, the height rise of the rotational centre of the shaft can be calculated with the following formula
where H = size of the motor (feet height)
Δt = difference between the alignment and the working temperatures (about 30°C)
Remark: the formula is based upon the standard thermal expansion of the steel, say about 0,01 mm for meter and for centigrade degree of temperature difference.
The same formula is applicable even for the driven machine. The driven machine manufacturer must, in any case, give the right calculated value.
The relevant measurements require that the machine rotor can be turned.
If a horizontal machine with plain bearings has been at standstill for a long period of time, then the oil film between the bearings shells and the shaft will have been pressed out by the weight of the rotor i.e. the bearings will be dry.
Therefore, before turning the rotor, approximately 100 - 200 cm3 of oil must be manually fed into each bearing. This can be done through the openings in the top of the bearing housing. The oil should be poured in using a funnel. If the manufacturer has not given details for setting radial displacement on the cold machine, then the rule is that zero displacement should be set.
ALIGNMENT
The following must be observed when coupling two or more machines together.
The coupling halves must be exactly aligned to each other, following the fundamental rule that the shaft train is to be exactly horizontal (or vertical for vertical machines). The shaft being coupled must naturally be exactly concentric to each other and the coupling end faces exactly parallel.
HORIZONTAL MACHINES WITH SLEEVE BEARINGS
Motors with sleeve bearings allow a certain axial float of the shaft. It is very important to remember that the motor cannot withstand any axial force from the driving machine. All axial forces must be withstood by the driven machine. Than the coupling must be of limited axial float type in order to guarantee that the sides of the bearings do not go in contact with the shoulders of the shaft. The motors are designed for 6 mm of total axial float.
The coupling has to be made with the rotor standing on its natural running centre. Consult the specific technical documentation to obtain the exact value of the distance between the coupling shoulder on the shaft and the red mark on the external seals of the DE side bearings. Axially move the motor until it is assured that continuos free axial movement is possible between the coupling halves to allow the thermal expansion of the shaft (without damaging the bearings) and the maintenance or the substitution of the coupling.
INSTRUCTIONS FOR CHECKING ALIGNMENT
Each alignment check is to be preceded by a run-out check on the coupling flanges.
HORIZONTAL MACHINES
Radial misalignment (Table 1) and angular misalignment (Table 2) in the vertical plane can be corrected on electrical machines by inserting shims under the machine feet.
Refer also to the chapter “Machine foundations and mountings”. Lateral radial misalignment (Table 1) and lateral angular misalignment (Table 2) can be corrected on electrical machines by moving the machine in the lateral direction.
VERTICAL MACHINES
Radial misalignment (Table 1: vertical = lateral) can be corrected on electrical machines by moving the whole machines.
If the flanges are provided with spigots, then the correction can be made on either of the two mating flanges.
If flanges are not provided with spigots, correction can be made by moving the whole machine radially within the clearance allowed between the holes and the fastening bolts in the coupling flanges.
Angular misalignment (Table 2: vertical = lateral) can be corrected by inserting shims between the flanges covering the greatest area of flange face as possible.
DOWEL PINS INSERTION.
When the motor design provides the dowels pins between the frame and the basement, the pins must be positioned and fixed. It is also good practice, in every case, to fix the axial and lateral position of the motor with jig locators. The dowel pins insertion shall be done after the positive result of the alignment operation and the check at "warm" condition, after the motor and the driven machine have reached their working steady state temperature.
BELT DRIVE
Motors with belt drives are always equipped with cylindrical roller bearing at the D end.
Do not exceed the design radial force indicated by the specific technical documentation.
Make sure that the driving and the driven pulleys are correctly aligned.
Radial misalignment
a1, b1, c1, and d1, are readings from the dial indicator R at the locations a = top, b = bottom, c = right, d = left. The readings are entered in the formulas to obtain the values of radial misalignment (Table 1, Fig. 1).
Table 1
Measuring location
1st Measurement
2nd Measurement
Example - measures in hundredth of mm
Vertical
Top
Bottom
Difference
Half difference= misalignment
+ Left-hand coupling is higher than the right-h. one
Left-hand coupling raised by 0,03 mm
- Left-hand coupling is lower than the right-h. one
Lateral
Right
Left
Difference
Half difference= Misalignment
+ Left-h. coupl. displaced to right of right-h. coupl
Left-hand coupling
- Left-h. coupl. displaced to left of right-h. coupl.
Moved 0,1 mm to left
Check for measuring error
Fig 1
Schematic for Table 1
Radial misalignment of the two coupling halves must be read in the 4 position each of 90° at same distance.
Maximum permissible radial misalignment (vertical and lateral misalignment)
Gear coupling Δ r = ± 0,05 mm
Flexible coupling (e.g. rubber-bushed coupling) Δ r = ± 0,10 mm
Axial gap and misalignment
The axial gap is determined by taking readings from the two dial indicators A I and A II, whereby the first reading from the top indicator A I is designated by e1 and that from the bottom indicator A II by h1. The values for vertical and lateral misalignment can be determined as shown in Table 2; axial displacement (in example 0,2 mm) during the measurement does not affect the results (Fig. 2).
Table 2
Measuring location
Dial AI
Dial AII
Example - measures in hundredth of mm
Vertical Gap
Top
Bottom
Gap
+ The gap is greater at the top
The gap is greater by 0,1 mm at the top.
- The gap is greater at the right
Lateral Gap
Left
Right
Gap
+ The gap is greater at the left
The gap is greater by 0,06 mm at the left.
Fig. 2
Schematic for Table 2
- The gap is greater at the right
Radial misalignment of the two coupling halves must be read in the 4 position each of 90° at same distance.
In the example it is assumed that an axial movement of the shaft of 0,2 mm took place during the measurement.
Maximum permissible value of vertical and lateral gap:
Gear coupling Δ b = ± 0,05 mm
Flexible coupling (e.g. rubber-bushed coupling) Δ b = ± 0,10 mm
Axial gap and misalignment
The axial gap is determined by taking readings from the two dial indicators A I and A II, whereby the first reading from the top indicator A I is designated by e1 and that from the bottom indicator A II by h1. The values for vertical and lateral misalignment can be determined as shown in Table 2; a minimal axial displacement (in example 0,2 mm) during the measurement does not affect the results (Fig. 2).
Axial displacement.
There must be sufficient axial clearance between the two coupling halves to accept a thermal expansion of 1 to 2 mm from the machine shaft.
Δa = 3 ± 1 mm, or in conformity with coupling manufacturer data
EARTH CONNECTIONS
Connect the machine frame, the terminal box and the associated equipment to the earth with cables of suitable section in order to avoid any harmful potential on the metallic external structure.
Mark the machine and the terminal boxes with earth symbols according to the relevant national standards.
AUXILIARY CIRCUITS
Check the correct connections of all the auxiliary circuits.
Terminals of auxiliary equipments which are normally under voltage when the motor is switched off (i.e. space heaters) are correspondingly labelled.
WARNING!
take all the necessary precaution working on circuits that can be under voltage.
INSULATION RESISTANCE
Before a medium voltage asynchronous motor is started up for the first time (or after a long period of standstill) the stator winding insulation shall be checked. The measured value of the insulation resistance provides information about the humidity and dirtiness of the insulation. Unsuitable transportation or storage conditions might subject the machine to extremely moist condition. If the minimum value of insulation resistance cannot be reached, a drying process must be considered.
Insulation resistance measurement
Measure the insulation resistance before connecting the feeding cables to the motor terminals.
WARNING!
before any measurement of Insulation Resistance be sure that no potentially explosive atmosphere is present in the ambient.
The instruments for the insulation resistance measurement (Megger or similar) apply direct voltage between the winding under test and the metallic parts of the motor connected to earth; the resistance value shall be taken after one minute after the application of the voltage. The windings not under test and the temperature detectors must be connected to earth. Usually the stator three-phase winding is measured as a whole, but if the star point can be opened, the measurement can be done phase by phase. For safety reason, after the measurement the winding under test has to be immediately connected to earth.
The test voltage, according to the available instrument, is normally between 500 and 2500 Volt.
The following criteria are valid:
a) For low voltage machine, the test voltage is 500 Volt maximum.
b) Equal values of insulation resistance are obtained with test voltage between 500 and 2500 Volt.
Test voltage of 500 Volt is therefore suggested as a rule.
Phase by phase measurement
Test instrument
(Megger type) 500 Volt d.c.
Complete winding measurement
Test instrument
(Megger type) 500 Volt d.c.
Minimum allowed values of insulation resistance
For safe (human safe) starting of the motor, the minimum allowed value for the stator winding insulation resistance is:
R 1 min (20°C) = [ 3 x (1 + Un) ] MΩ
Un =nominal voltage of the motor in kV (line to line).
This value is referred to the complete winding. One phase gives a value that is roughly double.
New machines and machines with new and dry windings have normally insulation resistance values much higher.
As a rule of thumb, the expected value for new windings, suggested for the commissioning, is
R 1 min (20°C) > [ 30 x (1 + Un) ] MΩ
Insulation resistance depends mainly from the temperature of the winding. The above mentioned values are referred to 20°C.
The rise of temperature of 10°C practically halves the value of the insulation resistance and vice-versa.
For example, if a winding at 40°C has insul. res. of 20 megaohm, this corresponds to 80 megaohm at 20°C.
This last is the value to be compared with the minimum allowable values.
Temperature detectors inserted into the winding have insulation resistance usually around 1000 megohm.
DRYING THE MOTOR
If, due to unsuitable transportation or storage conditions, the insulation resistance value falls under the minimum allowable value for the human safety, a drying process becomes necessary.
The rules to follow for the machine drying are reported under the “Maintenance” section of this manual. As there described, the drying of electrical machines requires hot and dry air circulation inside the motor.
EEx d motors are totally enclosed machines. As a consequence, to circulate hot air inside the motor, the disassembling of some external components becomes necessary.
It is important to remember that the assembling and disassembling operations of the EEx d equipments must be done by qualified operators and shall be verified by authorised personnel, in order to guarantee the maintaining of the explosion proof characteristics.
We suggest, in this case, to entrust of the closing and opening operations a Service organisation qualified for interventions on EEx d equipments.
TEMPERATURE DETECTORS INSERTED INTO THE WINDING.
Resistance temperature detectors, Pt100 type are usually provided. Refer to the specific technical documentation for possible other solutions.
The temperature detectors are normally connected to an alarm and trip protection system. Depending from the detected temperatures, an alarm is activated and trip of the feeding circuit breaker can follow.
The suggested settings of this protection system should be 10°C over the operating temperature with maximum continuos load and maximum ambient temperature.
Depending on the design temperature class of the electrical equipments belonging to Group II, the protection shall be set according the following maximum values:
Temp. class T3 T4
Alarm : 145°C 140°C
Trip : 150°C 145°C
The a.m. values guarantee that the maximum surface temperature does not exceed the limit of the relevant temperature class (T3 or T4).
In case of motors fed by inverters the a.m. limits shall be reduced by about 15°C to take in account the heaviest work conditions.
ELECTRICAL CONNECTIONS
Warning! during the installation works no drills of holes on the frame, terminal boxes or covers of the motor are allowed.
The feeding cables shall be provided respecting, for the whole installation, the EMC conditions required by the relevant Standards.
We suggest to use screened cables, whose screens shall be connected to the protection earth.
Motors fed by inverters requires particular attention for this purpose. Refer to the specific technical documentation of the inverter.
All the cable entrances into the terminal boxes must be done using the cable glands indicated by the specific technical documentation.
The responsibility for using the correct types of cable glands lies always on the installer of the motor.
CONNECTIONS TO THE MAIN TERMINAL BOX
Look at the connection diagram reported on the specific technical documentation and attached into the terminal box.
It is important to verify that the supply voltage and frequency have the values corresponding to the indication of the nameplate.
Sections and types of the feeding cables and their terminations must be of correct size and appropriate to the maximum value of the absorbed current. In case of special requests take care of the fault current too.
EEx d main terminal box
EEx e main terminal box
The winding terminals (bushings) are marked with the letters U – V – W in accordance with IEC 60034-8 Standards. The neutral terminal, if any, is marked with the letter N.
The connection with a feeding system having the correct phase sequence (L1 – L2 – L3) guarantees the right rotation sense of the shaft in accordance with the arrow put near the shaft on D.E. side.
In case of wrong phase sequence, the rotation sense of the shaft con be inverted simply by the commutation of the connection to the U and W terminals.
CONNECTION TO THE AUXILIARY TERMINAL BOX
One or more auxiliary terminal boxes can be provided.
The standard solution provides one auxiliary terminal box having a separator barrier between the terminals of the power circuits (space heaters, possible external fan etc.) and the measuring and protection system terminals.
Make sure that all the monitoring instrument connections are properly wired in accordance with the electric diagram contained into the specific technical documentation and verify their proper operation.
Warning! take all the necessary precaution working on circuits that can be under voltage.
EEx d IIB auxiliary terminal box
EEx d IIC auxiliary terminal box
BEARINGS
ANTIFRICTION BEARINGS (Rolling-contact bearings)
The bearings are filled with lithium soap grease before delivery.
Periods of standstill lasting some months, as for storage for instance, can result in oil separation from the bearing lubricating grease. Dismantle the outer bearing cover and, if this is the case, remove the grease and oil residue. Replace the removed grease with fresh grease of proper type and close again the bearing cover.
Bearing temperature monitoring. If provided the temperature detectors shall be set at the lower possible temperature based on the test results and operating condition. The maximum values recommended for normal operating temperature with standard lubricants and ambient temp. at 40°C are:
Alarm : 90°C (194°F)
Trip : 100°C (212°F)
If high temperature grease is used (i.e. for machines rated at class F working temperature) the a.m. limits can be set 10°C (28°F) higher. Refer to the specific technical documentation.
SLEEVE BEARINGS
Sleeve bearing machines are delivered without oil. On machines with self-cooled bearing, i.e. not having a separate oil supply system, the oil is carried to the bearing faces by oil rings.
During longer shut-down periods the oil film between the bearing shell and the bearing journal will be pressed out by the weight of the rotor, i.e. the bearing will be dry! Therefore, prior to rotate the shaft (even by hand), at least 100 to 200 cm³ of oil must be introduced manually into each bearing. This can be done by removing the screw-plug or vent-filter located on top of the bearing cover and inserting a funnel into the exposed opening.
Be sure to use the correct type of oil.
When introducing the lube oil, only fill to the correct level i.e. up to the middle of the oil sight window. A higher oil level is not recommended as this could cause oil leakage at the seals during operation.
Machines cooled by an axial external fan (HXR or AMDR-AMDT types) are provided on N.D.E. side with a vent tube (with filter) coming out from the ventilation hub to avoid the pressurisation of the bearing enclosure.
Separately cooled plain bearings. The bearings are connected to an oil supply system, which should be in operation before the machine is started up and remain in operation until the machine is turned down. The maximum oil inlet temperature of the bearings should not exceed 65°C.
Bearing temperature monitoring. If provided the temperature detectors shall be set using the same criteria applicable for antifriction bearings. The maximum values recommended for normal operating temperature with standard lubricants and ambient temp. at 40°C are:
Alarm : 90°C (194°F)
Trip : 100°C (212°F)
Laying the oil lines. Flexible pipe elements must be fitted between the connection pipe or flange on the motor and the oil supply lines to attain a tension-free connection. This ensures for better, oil-tight connection and also helps to avoid electrical insulating parts from being damaged, if such are fitted.
Before fitting, the lines should be tapped gently to clear out scale, rust and sand, then washed out with inhibited hydrochloric acid and rinsed with rinsing oil. The inhibitor should be used to supplier’s instructions.
The oil return line must have a continuous slope of 5% (= 50 mm per 1000 mm of length) from the connection flange on the motor bearing to the oil tank. This is the minimum permissible slope!
Remember that the oil level of the bearings will increase if the oil moves too slowly in the discharge tubes. This can result in oil leaks or disturbance in the flows.
On principle, oil return lines should be kept as short as possible. Their free cross-section should be at least as large as that of the outlet. Bends should be avoided where possible. To avoid risk of oil damming up or pressure build-up in the bearings, these lines should contain no double bends or siphons. Specifications on drawings have to be taken into account, where applicable.
Inlet points have to be arranged in the direction of flow. Pipe sections must be large enough to obtain the following oil flow velocities:
- Oil inlet (full pipe section) less than 1.5 m/sec.
- Oil return (full pipe section) less than 0.17 m/sec.
In order to suppress the formation of oil foaming, vertical drops > 1 m are to be avoided.
When the bearing seals incorporate a sealing-air arrangement, it is important to ensure that there is adequate venting of the housing.
This can be done via the oil return line or via a venting filter sufficiently sized to prevent the escape of oil vapour.
1) Return line 2) Vent
3) Oil vapour exhaust
In case of systems with a high oil flow (e.g. oil supply systems), it may be economical to recondition the lubricating oil for further use. In such cases, the oil will require testing for physical, chemical and mechanical properties during commissioning. Appropriate data sheets with test instructions are available from us on request.
SUGGESTION FOR DESIGN OF OIL SUPPLY UNITS
The oil tank must be fitted with an oil vapour exhaust to produce a negative pressure in the tank. This negative pressure ensures that a backpressure of oil does not build up in the oil lines and that the bearing enclosure is vented. At the same time the oil will be “degassed” and separated from the entrained air.
The oil tank must be fitted with a condensation separator and, if required by low ambient temperature, also with a heater. A suitable internal protection against corrosion will help to avoid oil contamination.
The oil return line must enter the oil tank above the oil level (Var. A). Should the oil return line be immersed, vent holes must be provided so that oil– borne air can escape (Var. B).
The oil supply line must be located in such a way that at no operating condition will the oil level fall below it.
Filters must remove particles larger than 0.040 mm and have a magnetic separator. If required for operational reasons change-over double filters must be fitted which can be cleaned during operation i.e. without turning off the oil supply.
ABB cannot accept any responsibility for oil leakage from the bearings or oil lines if the aforementioned conditions are not fulfilled.
BEARING INSULATION.
The bearing insulation is at the customer’s request. Machines of all sizes can be provided with insulated bearings at both ends at the customer’s request.
Details on bearing insulation are given on a separate sheet “Bearing insulation”, i.e. whether the end-shield or the bearing shell, one or both bearings are insulated, and whether there is provision for bridging the bearing insulation for test purposes.
Translation - Serbian 4.5. Odredite odgovarajuću lokaciju za poravnanje elemenata (Sl. 1) i stavite ih na mjesto. Elemente za poravnanje po mogućnosti učvrstite smesom za vezivanje kao što je Sikadur ili slično. Stavite mašinu sa postoljem na elemente za poravnanje i prilagodite nivo. Položaj osovina mašine mora biti približno u skladu sa pokazateljima na dimenzionim crtežima mašine
4.6. Horizontalnim klizanjem i vertkalnim podešavanjem vijaka za niveliranje poravnajte motor sa delom za kuplovanje susjedne mašine.
5. Upute za fugovanje
Rukovodioci gradilišta su odgovorni za izvršenje radova na odgovarajući i profesionalan način. Temelji i delovi za pričvršćenje moraju biti u potpunosti čisti i neobojeni. Nikada ne radite fugovanje na delovima koji su zamašćeni ili obojeni običnom bojom.
5.1. Fugovanje u temeljnim vijcima (sl. 2). Ponovo proverite da li su temeljne površine čiste i vlažne. Ispunite rupe za anker vijke mršavim betonom do visine od oko 10 mm ispod gornjeg ruba i po mogućnosti provibrirajte beton. Minimalno vreme vezivanja je 72 časa. Nakon isteka ovog vremena, matice za zatezanje (16) sa mogu po potrebi pritegnuti. (Pomerite motor ako je neophodno). Prilikom pritezanja treba voditi računa da ne dođe do uvrtanja kućišta ili postolja mašine. Nakon pritezanja, ponovo proverite poravnanje osovine i korigujte je ako je potrebno.
5.2. Fugovanje u prolaznim vijcima (sl. 3). Ako su isporučeni prolazni vijci, postavite anker ploče (8) i stegnite vijke. Mora se voditi računa da prilikom zatezanja ne dođe do uvrtanja kućišta ili postolja. Nakon zatezanja ponovo proverite poravnanje osovine i korigujte je ako je potrebno. Isušite temeljne rupe za vijke (6) I napunite elastičnim filerom (13) do visine 5-10 mm od gornjeg ruba. ABB preporučuje granularnu smesu sa sintetičkim filerom, kao što je LUSTREX-Polystyrene 2220 or 4220. Dobavljač: MONSANTO PLASTICS & RESINS CO. 800 N. Lindbergh Blvd., St. Louis, No. 63166 (USA). Pesak se ne može koristiti kao filer. Nakon popunjavanja filerom (13), izvršite zaptivanje vrha temeljnih rupa elastičnom smesom otpornom na maziva, kao što je Sikaflex - 11 FC.
5.3. Završite fugovanje u skladu sa odgovarajućim nacrtima i osnovom temelja. Izvibrirajte okruženi beton (12) Izlijte temeljno postolje što bliže završnom sloju (5-10 mm ispod gornje strane temeljnih ploča mašine) (Mešavina 5.5). Vodite računa da su temeljne ploče mašine u potpunosti pokrivene smesom, te po potrebi izvršite nabijanje.
5.4. Korišćenje pripremljene betonske smese od proverene kompanije smanjuje rizik lošeg kvaliteta i zato se preporučuje nabavka iste. Osnovno pravilo je da se standardi kvaliteta odrede kada se naručuju manje količine. Poželjno je raditi sa betonom čvrstoće B25 = 25 N/mm2.
Ako je nemoguće obezbediti pripremeljnu smesu, i u odsustvu uputa za određivanje omjera u smesi, dole navedene brojke mogu se koristiti kao vodič
5.5. Betonske mešavine P300 and P350 su pogodne za ispunu temelja mašine i sadrže 300 kg, odnosno 350 kg cementa po metru kubnom. Omjer peska i šljunka za metar kubni gotovog betona (1,2 kubna metra smese) su sledeće:
40% Fini pesak Granulacija 0-5 mm
25% Grubi pesak Granulacija 6-15 mm
35% Šljunak Granulacija 16-35 mm
100-110 litara vode
Sledeća mešavina se može koristiti za fugovanje rupa za anker vijke:
2/3 Fini pesak Granulacija 0-5 mm
1/3 Grubi pesak Granulacija 6-15 mm
Kada se koriste druge mešavine, uvijek je potrebno izliti i testirati uzorak. Mogu se koristiti samo čisti i oprani materijali. Dobra čvrstoća betona postiže se visokom standardnom čvrstoćom cementa, niskim odnosom voda-cemet, kao i vibracionim nabijanjem.
Sadržaj vode (I)
Odnos voda-cement = --------------------------------
Sadržaj cementa (kg)
Odnos voda-cement ima presudnu ulogu za finalnu čvrstoću betona. Poželjno je da odnos voda-cement bude između 0,3 i 0,45, s tim da se sadržaj vode u agregatu mora uzeti u obzir. Nije dozvoljeno imati odnos voda-cement > 0,6.
Beton se ne sme isušiti ili smrznuti tokom prvih 48 sati. Za to vreme, temepratura temelja ne sme pasti ispod 10°C. Optimalna temperatura sa proces vezivanja je 20°C ± 10°C. Pod normalnim okolnostima, temelj se može statički opteretiti 3 dana nakon izlijevanja.
6. Montaža mašine na posebno pripremeljnu čeličnu osnovu
U ovom slučaju se podrazumjeva da je čelični okvir (već propisno fiksiran za pod) pravilno poravnat sa susjednom mašinom. Provjerite utor za umetanje vijaka za pričvršćenje i spustite motor. Poravnajte motor sa nivelirajućim vijcima i podmetačima i stegnite vijke.
7. Testiranje prije kuplovanja
Sugeriše se da se provede test prije povezivanja zglobnih polovina za kuplovanje obe mašine. Pogledati upute za puštanje u rad.
Vreteno za poravnanje
Podne ploče sa temeljnim anker vijcima
Podne ploče sa temljenim prolaznim vijcima
1 Podne ploče
2 Podmetači
3 Vijci za stezanje
4 Štift (ako postoji)
5 Temeljni anker vijci
6 Temeljni prolazni vijci
7 Element za poravnanje
8 Anker ploča
9 Klizna ploča
10 Sintetička smesa za vezivanje
11 Betonski temelj
12 Fugovanje
13 Sintetička smesa za ispunu
14 Elastična smesa za zaptivanje
15 Kontra-matica
16 Matica za pritezanje
Fig. 1
Fig. 2
retighten
Fig. 3
Način montaže
Opšta pravila za temelje i montažu su slična pravilima za horizontalnu montažu. Pogledajte dokument Br. DMPB 6182 E. Najčešće, vertikalne mašine se montiraju na posebno pripremljene čelične temeljne ploče.
Montaža na čelične temeljne ploče
Proverite rupe za stezanje u čeličnoj temeljnoj ploči, očistite nasedne površine, spustite mašinu i izvršite poravnanje. Spojite mašine na mjestu rada. Ravnomerno stegnite vijeke za pričvršćenje, po pravilu dijagonale. Mašina mora po čitavom obodu naleći na priteznu flanšu. Nakon završnih provjera spustite motor na čeličnu ploču.
Preliminirana provera
Provera svih funkcionalnih delova je neophodna prije prvog kuplovanja. Žlebove i produžetke osovina treba proveriti u smislu odstupanja od dimenzija specificiranih u crtežima.
Takođe treba osigurati da su žlebovi produžetka osovine i produžetka kuplunga zaista parlaleni. Rotor mašine se balansira poluklinom.
Komponenete za kuplovanje treba balansirati na vretenu tako da poluklin ispunjava žleb.
Opšte informacije
Ovo su najčešću razlozi loše podešenih osovina za kuplovanje:
- Oštećenja na osovini, kuplungu ili žlebu (udubljenja, ispupčenja ili ostaci utiskivanja)
- Neparalelnost žlebova koja izaziva zaglavljivanje i preveliki lateralni pritisak na klinove i žlebove
- Klin previsok tako da nosi većinu tereta
- Klin ubačen u zašiljen produžetak osovine utiče na fukncionalnost zašiljenog ležišta i stoga se treba izbegavati Ako se klin ipak ubaci, ležište kuplunga mora biti maksimalno precizno podešeno. To znači da se osim zadate tolerancije kontakt između osovine i ležišta mora proveriti plavom tintom, žlebovi za obe osovine moraju se proveriti na potpuni paralelizam, a i najmanje nepravilnosti kao što su ispupčenja ili ostaci utiskivanja moraju se eliminisati.
Upute za montažu
Temeljito očistite i osušite sve kontaktne površine. Te površine nikada ne pokrivajte sa molibden disulfatom (Molykote) ili sličnim proizvodima. Preporučuje se tanak sloj ulja na osovini i ležištu.
Generalno, upute proizvođača za kuplovanje se primenjuju za spajanje i rastavljanje spojnih mesta.
Uobičajno je zagrijati spojna mjesta da bi se povećao zazor dva dela koja se uklapaju. Ako se vrši kuplovanje sa klinom, već postoji određen zazor između osovine i utora, tako da je zagrijavanje do 80°C (176°F) dovoljno za jednostavno kuplovanje.
Cilindrični i konusni kuplunzi (bez klina) se uvijek isporučuju bez zazora, tako da se moraju zagrijati kod kuplovanja. Svaki proizvođač obezbeđuje svoje upute.
VAŽNO! : Prilikom demontaže osovine kod kuplunga bez zazora, mora se izvršiti “uvećanje”. Uvećanje se uglavnom radi injektiranjem ulja pod visokim pritiskom u kružne žlebove povezane sa malim kanalima za injektiranje ulja.
Jako je važno da se prilikom kuplovanja izbegnu useci ili aksijalne zagrebotine koje bi sprečile nabijanje ulja. Ako se ulje na može nabiti, demontaža kuplunga može postati jako teška, pa čak i nemoguća.
Težina kuplunga može biti značajna, tako da je potrebno obezbediti odgovarajuću opremu i alat za podizanje
Aksijalni zazor
Vrijednost dozvoljenog aksijalnog opterećenja su date u dimenzionim nacrtima mašine. Aksijalni zazor u kuplungu mora biti odabran tako da bude dovoljno velik da prihvati odstupanja osovine sa mašine koja se kupluje. Naše mašine su obično opremeljene sa uvodnim ležajem na pogonskom kraju. Termička diletacija stoga može delovati na nepogonjeni dio i bez opterećenja kuplunga.
Uputstvo za demontažu
Demontiranje kuplunga sa klinom.
Demontiranje kuplunga se lako može uraditi pomoću radapcigera odgovarajućih dimenzija. Ne zaboravite zaštiti kraj osovine odgovarajućim mekanim materijalom na mjestu gdje se ostvaruje kontakt sa centralnim delom radapcigera (pogledati tačku A)
Demontaža kuplunga koji se montira bez zazora
U ovo slučaju potreban je odgovarajući uređaj za injektiranje ulja pod visokim pritiskom (reda 1000 bara i više), zajedno sa hidrauličnom dizalicom sposobnom da generiše snagu od 100 tona.
1 Vijak 5 Cevo za visoki pritisak
2 Zadržna ploča 6 Držač pumpe
3 Hidraučina dizalica 7 Uže
4 Uljna pumpa 8 Merač pritiska
Detaljne upute o celoj operaciji su opisane u uputstvu za kuplovanje, tako da predlažemo da pregledate taj dokument. Glavni koraci operacije su ovdje opisani više informativno
Demontaža kuplunga sa cilindričnom osovinom sastoji se uglavnom iz sledećih koraka
- Stavite hidrauličnu dizalicu izemeđu kraja osovine i kuplunga (preko odgovarajućih ploča i šipki) kako biste aplicirali aksijalnu silu između kraja osovine i unutrašnje površine kuplunga. Drugim riječima, sila koju generiše dizalica mora izbiti kuplung van kraja osovine.
- Odgovarajućim kranom rasteretite težinu kuplunga da sam kuplug ne bi opteretio kraj osovine, i da ne bi došlo da padanja kuplunga.
- Spojite uređaj za visoki pritisak na urezani otvor koji je obezbeđen za ovaj način kuplovanja
- Ubrizgajte ulje pod pritiskom u kružne utore kuplunga i podignite pritisak ulja do vrednosti koja je navedena u upustvu za korištenje. Ako u celom sistemu nema curenja ulja, promer kuplunga će se postepeno širiti, a ulje će izaći na bočne strane nakon određenog vremena (nakon cca 15 min)
- Pomoću hidraulične dizalice generišite aksijalnu silu između kuplunga i kraja osovine. Sila potrebna za izvlačenje je reda 50 tona.
- Skinite kuplung u jednom kontinuiranom koraku, bez prekidanja rada, kako biste održali pritisak ulja u sistemu.
U slučaju kuplovanja sa dva ili više unutrašnjih prečnika, pažljivo proučite i pridržavajte se uputa proizvođača.
UPUTSTVO ZA PORAVNANJE KUPLUNGA
Svrha ovog uputstva jeste da se positgne odgovarajuće poravnanje produžetka osovine bez ugaonog ili paralelnog smicanja. Ovaj uslov se može ispuniti pažljivim i preciznim radom. Uputsvo za poravnanje je podjednako primenjivo kako za krute, tako i za fleksibilne kuplunge i za sve tipove pogona.
Kao što je dobro poznato, linearne dimenzije metalnih objekata se menjaju promenom temperature. Dakle, pri poravnanju na temperature okoline, potrebno je proceniti centar rotacije pri radnoj temperaturi, kako bi se odredilo podešenje radijalnog smicanja na hladnoj mašini, a sve to da bi se postiglo idealno stanje nultog poravnanja na očekivanoj radnoj temperaturi. Za čelične konstrukcije, kao što je oklop motora, visina rotacionog centra osovine može se izračunati pomoću sledeće formule.
Gde je H = veličina motora (visina u stopama)
Δt = razlika u temperaturi pri poravnanju i radnoj temperaturi (oko 30°C)
Opaska: Formula je bazirana na standardnoj termalnoj ekspanziji čeika od oko 0,01 mm po metru i za razliku temperatura u stepenima celzijusa.
Ista formula se može primeniti za svaku pogonjenju mašinu, Za svaki slučaj, proizvođač mora dati korektno izračunate vrijednosti.
Mašina se postavlja tako da se rotor može okretati.
Ako je horizontalna mašina sa plošnim ležajevima dugo stajala, tada se nakupljeni sloj ulja između ležajeva i osovine istisne van pod težinom rotora, odnosno ležajevi se osuše.
Stoga, prije okretanja rotora, oko 100 - 200 cm3 ulja mora se uliti u svaki ležaj. Ovo se može učiniti kroz otovore na vrhu kućišta ležaja. Ulje treba nasuti korištenjem lijevka. Ako je proizvođač dao detalje za podešenje radijalnog smicanja hladne mašine onda je pravilo da se podesi nulto smicanje.
PORAVNANJE
Prilikom kuplovanja dvije ili više mašina, potrebno je obratiti pažnju na sledeće:
Delovi za kuplovanje moraju biti u potpunosti poravnati, prateći osnovno pravilo da osovina mora biti u potpunosti horizontalna (ili vertikalna za vertikalne mašine). Osovine koje se kupluju moraju biti potpuno koncentrične, a lica krajeva moraju biti u potpunosti paralelna
HORIZONTALNE MAŠINE SA KLIZNIM LEŽAJEVIMA
Motori sa kliznim ležajevima dozvoljavaju određen stepen slobode osovine. Jako je važno znati da motor ne može podneti aksijalne sile pogonske mašine. Sve aksijalne sile mora trpiti pogonjena mašina. Kuplung tada mora imati ograničen aksijalni hod kako bi se garantovalo da strane ležaja ne dođu u kontakt sa ramenima osovina. Motori su dizajnirani za 6 mm totalnog aksijalnog hoda.
Kuplovanje se mora uraditi kada je rotor postavljen u prirodni centar vrtnje. Konsultujte specifičnu tehničku dokumentaciju kako biste dobili tačne vrijednosti razmaka između spojnog ramena na osovini i crvenih oznaka na vanjskoj strani bočnih ležajeva Aksijalno pomerite motor dok se ne osigura kontinuirano kretanje između spojnih polovina kako bi se omogućila termička ekspanzija osovine (bez oštećenja ležajeva) i održavanje ili zamjena kuplunga.
UPUTSTVO ZA PROVERU PORAVNANJA
Svakoj proveri mora prethoditi provera obrtanja flanši za kuplovanje
HORIZONTALNE MAŠINE
Radijalno odstupanje (Tabela 1) i ugano odstupanje (Tabela 2) po vertikalnoj ravni kod električnih mašina mogu se korigovati ubacivanjem podmetača ispod stopa mašine. Pogledajte odjeljak “Temelji mašine i montaža”. Lateralno radijalno odstupanje i lateralno ugaono odstupanje kod električnih mašina mogu se korigovati lateralnim pomeranjem mašine
VERTIKALNE MAŠINE
Radijalno odstupanje (Tabela 1: vertikalo = lateralno) kod električnih mašina može se korigovati pomeranjem cele mašine. Ako su flanše opremljene cevnim ispustima, tada se korekcija može napraviti na flanši sa bilo koje strane kuplunga. Ako flanše nemaju ove ispuste, tada se korekcija vrši radijalnim pomeranjem cele mašine, ostavljanjem zazora između rupa i zatezanjem vijaka flanši koje se kupluju. Ugaono odstupanje (Tabela 2: vertikalno = lateralno) može se korigovati ubacivanjem podmetača između flanši tako da podmetači pokriju što je moguće veću površinu flanše.
UMETANJE ŠTIFTOVA
Kada je dizajnom motora predivđeno ubacivanje štiftova između tela i osnove, tada se štiftovi moraju postaviti i fiksirati. Također je dobra praksa da se za svaku slučaj aksijalna i lateralna pozicija motora fiksiraju pomoću šablona. Ubacivanje štiftova treba izvršiti nakon što izvrši poravnanje i provere u toplom režimu, kao i nakon što pogonjena mašina postigne svoju radnu temperaturu.
POGON PREKO REMENICE
Motori sa remenicom su uvijek opremljeni cilindričnim ležajevima na D kraju. Ne smete preći radijalnu silu koja je zadata u tehničkoj dokumentaciji. Obezbedite da su pogonjena i pogonska kolotura korektno poravnate.
Radijalno odstupanje
a1, b1, c1, i d1, su očitanja sa brojčanika R na mjestima a = vrh, b = dno, c = desno, d = lijevo. Očitanja se unose u formule da bi se dobile vrijednosti radijalnog odstupanja (Tabela 1, Sl. 1).
Tabela 1
Merno mesto
1. Merenje
2. Merenje
Primer – očitanje u stotim delovima mm
Vertikalno
Vrh
Dno
Razlika
Polu-razlika= odstupanje
+ leva ploča je viša od desne
Leva ploča se diže za 0,03 mm
- leva ploča je niža od desne
Lateralno
Desno
Levo
Razlika
Polu-razlika= odstupanje
+ Leva ploča odstupa udesno
Leva ploča pomerena
- Leva ploča odstupaulevo
0,1 mm ulevo
Proverite greške merenja
Sl 1
Šematski za tabelu 1
Radijalno odstupanje dve ploče za kuplovanje mora se očitati u četiri pozicije, s međusobnom udaljenošću od 90° pri istom odstojanju.
Maksimalno dozvoljeno radijalno odstupanje (vertikalno i laterlano)
Kruti kuplung Δ r = ± 0,05 mm
Fleksiblni kuplung (npr. gumirani kuplung) Δ r = ± 0,10 mm
Aksijalni zazor i odstupanje
Aksijalni zazor se određuje očitanjem dva brojčanika A I and A II, gdje je prvo očitanje sa gornjeg brojčanika A I određeno kao e1 a ono sa donjeg brojčanika A II kao h1. Vrednosti vertikalnog i lateralnog odstupanja mogu se odrediti kao što je prikazano u Tabeli 2; aksijlano odstupanje (u primeru 0,2 mm) za vreme merenja ne utiče na rezultate (Sl. 2).
Tabela 2
Merno mesto
Brojčan. AI
Brojčan. AII
Primer – mere u stotim delovima mm
Vertikalni zazor
Vrh
Dno
Zazor
+ Zazor je veći da vrhu
Zazor je za 0,1 mm veći na vrhu.
- Zazor je veći na dnu
Lateralni zazor
Levo
Desno
Zazor
+ Zazor je veći na levoj strain
Zazor je za 0,06 mm veći na levoj strani.
Sl. 2
Šematski za tabelu 2
- Zazor je veći na desnoj strani
Radijalno odstupanje dve ploče za kuplovanje mora se očitati na četiri pozicije međusobno udaljene 90° sa istog odstojanja.
U ovom primeru pretpostavljeno je da se tokom merenja osovina aksijalno pomerila 0,2 mm
Maksimalna dozvoljena vrednost vertikanlog i lateralnog zazora
Kruti kuplung Δ b = ± 0,05 mm
Fleksibilni kuplung (npr. gumirani kuplung) Δ b = ± 0,10 mm
Aksijalni zazor i odstupanje
Aksijalni zazor se određuje očitanjem dva brojčanika A I and A II, gdje je prvo očitanje sa gornjeg brojčanika A I određeno kao e1 a ono sa donjeg brojčanika A II kao h1. Vrednosti vertikalnog i lateralnog odstupanja mogu se odrediti kao što je prikazano u Tabeli 2; aksijlano odstupanje (u primeru 0,2 mm) za vreme merenja ne utiče na rezultate (Sl. 2).
Aksijalni razmak.
Mora postojati dovoljan aksijlani razmak između dve ploče za kuplovanje da bi se kompenzovala termička diletacija osovine mašine od 1 do 2 mm
Δa = 3 ± 1 mm, ili u skladu sa uputama priuzvođača
UZEMLJENJE
Spojite telo mašine, priključne kutije i pripadajuću opremu sa kablovima za uzemljenje odgovarajućeg preseka da bi se eliminisala pojava opasnog potencijala na metalnim vanjskim površinama.
Označite mašinu sa markerima “uzemljeno” u skladu sa relevantnim državnim standardima
POMOĆNI STRUJNI KRUGOVI
Proverite veze prema svim pomoćnim strujnm krugovima. Stezaljke i pomoćna oprema motora koja je u radu pod naponom (npr. grijači prostora) obeleženi su na odgovarajući način.
UPOZORENJE!
Preduzmite sve mere zaštite kada radite na krugovima koji mogu biti pod naponom
OTPOR IZOLACIJE
Prije nego što se srednjenaponski asinhroni motor stavi u pogon po prvi put (ili nakon dugotrajnog mirovanja), mora se proveriti izolacija namota statora. Izmerena vrednost izolacije daje informacije o vlažnosti i zaprljanosti izolacije. Neodgovarajući transport ili uslovi skladištenja mogu dovesti do izlaganja motora ekstremnoj vlazi. Ako se ne može postići minimalna vrednost otpora, mora se razmotriti primena procesa sušenja.
Merenje otpora izolacije
Izmerite otpora izolacije prije spajanja napojnih kablova na priključne kutije motora.
UPOZORENJE!
Prije bilo kakvog merenja, osigurati da se u zračnom prostoru ne nalaze potencijalno eksplozivne čestice.
Instrumenti za merenje otpora izolacije (Megger ili slični) direktno narine napon između namotaja koji se testira i metalnog kućišta spojenog sa zemljom. Vrednost otpora se registruje jedan minut nakon priključenja napona. Namotaji koji se ne testiraju, kao i termo sonde, moraju se spojiti sa zemljom. Obično se tronamotajni stator mjeri kao celina, ali ako se zvezdište ne može otvoriti, merenja se vrše namot po namot. Zbog bezbednosti, namot koji se testira mora se odmah nakon merenja spojiti sa zemljom.
Ispitni napon je obično između 500 i 2500 V.
Moraju se zadovoljiti sledeći kriterijumi
a) Za niskoanponske mašine, maksimalni ispitni napon je 500 V
b) Podjednake vrednosti otpora izolacije se moraju postići sa isptinim naponima između 500 i 2500 V.
Stoga se ispitni napon od 500 V predlaže kao pravilo.
Ispitivanje namot po namot
Ispitni instrument
(Megger) 500 V d.c.
Merenje kompletnih namotaja
Ispitni instrument
(Megger) 500 V d.c.
Minimalno dozvoljene vrednosti otpora izolacije
Za startanje motora koje je bezbedno po ljude, minimalno dozvoljena vrednost otpora statorskih namotaja je:
R 1 min (20°C) = [ 3 x (1 + Un) ] MΩ
Un =nominalni napon motora u kV (linijski).
Ova vrednost se odnosi na kompletne namotaje. Jedan namotaj ili faza treba imati vrednosti koje su okvirno dvostruko veće. Nove mašine sa novim i suhim namotajima obično imaju otpor izolacije mnogo veći.
Generalno, očekivana vrednost za nove namotaje prije prvog puštanja u rad je:
R 1 min (20°C) > [ 30 x (1 + Un) ] MΩ
Otpor izolacije uglavnom zavisi od temperature namotaja. Gore pomente vrednosti važe pri temperature do 20°C.
Porast temperatue od 10°C praktično polovi vrednost otpora izolacije i obratno Na primer, ako pri temperaturi od 40°C namot ima otpor izolacjie od 20 megaoma, to odgovara 80 megaoma pri 20°C.
Ovo zadnja vrednost se treba uporediti sa minimalnim dozvoljenim vrednostima.
Termo sonde u namotima imaju otpor izolacije reda 1000 megoma.
SUŠENJE MOTORA
Ako vrednost otpora izolacjie usljed transporta ili lošeg skladištenja padne ispod vrednosti dozvoljenih za bezbednost ljudi, process sušenja je neophodan. Upute za održavanje mašine suhom nalaze se u odelu “Održavanje” ovog priručnika. Kao što je tamo opisano, sušenje električne mašine zahteva kruženje vrućeg i suvog zrak unutar motora.
EEx d motori su potpuno oklopljeni. Posljedično, da bi vruć zrak cirkulisao kroz motor, potrebna je demontaža nekih vanjskih kompenenti.
Važno je upamtiti da montažno-demontažne radove na EEx d opremi mora vršiti visoko kvalifikovano osoblje kako bi se obezbedilo održanje protu-eksplozivnih karakteristika.
Mi predlažemo da se u ovom slučaju otvaranje i zatvaranje motora prepusti servisnoj organizaciji koja je kvalifikovana za intervencije na EEx d opremi.
TERMO SONDE UBAČENE U NAMOTE
Otporne termo sonde tipa Pt100 se najčešće koriste. Provjerite tehničku dokumentaciju ako su u pitanju sonde drugog tipa.
Termo sonde su najčešće povezane sa alarmom i tripom zaštitnog sistema. Zavisno od detektovane temperature, aktivira se alarm, a potom trip vrši isključenje prekidača napojnog voda.
Predložena podešenja zaštitnog sistema trebaju biti za 10°C iznad radne temperature koja se postiže pri kontinuiranom maksimalnom opterećnju i pri maksimalnoj vanjskoj temepraturi.
Ovisno o vrsti temperaturne klase za električnu opremu Grupe II, zaštita će se podesiti u skladu sa sledećim maksimalnim vrednostima:
Temp. klasa T3 T4
Alarm : 145°C 140°C
Trip : 150°C 145°C
Ove vrednosti garantuju da maksimalna temperatura površine neće preći limite za odgovarajuću temepraturnu klasu (T3 ili T4).
Ako se motor napaja preko frekventnih pretvarača, granice će se spustiti za dodatnih 15°C kako bi se uzeli u obzir najteži mogući uslovi rada.
ELEKTRIČNI SPOJEVI
Upozorenje! Za vreme montaže, nisu dozvoljena bušenja na kućištu, priključnim kutijama ii poklopcu motora.
Napojni kablovi se moraju odabrati prema uslovima rada ostalih instalacija, te u skladu sa EMC standardima
Mi sugerišemo korišćenje ekraniziranih kablova, sa napomenom da se plašt uzemlji. Motori pogonjeni frekventnim pretvaračima zahtevaju posebnu pažnju, pa je potrebno slediti uputstva proizvođača frekeventnih prvarača.
Svi uvodi u priključne kutije moraju se izvršiti korištenjem odgovarajućih uvodnica
Odgovornost za korišćenje odgovarajućih kablovskih uvodnica uvijek leži na osoblju koje pušta moror u rad.
SPOJ NA GLAVNU PRIKLJUČNU KUTIJU
Pogledajte spojni dijagram koji se nalazi u tehničkoj dokumentaciji za prikljčnu kutiju.
Važno je ustanoviti da radni napon i frekvencija odgovaraju onom što je navedeno na natpisnoj pločici motora. Preseci i tipovi napojnih kablova moraju biti odgovarajuće dimenzionisani tako da mogu podneti maksimalnu vrednost struje. U posebnim slučajevima, obratiti pažnju i na struje kvara.
EEx d glavna priključna kutija
EEx e glavna prikljčna kutija
Priključci namota (bušinzi) su označeni slovima U – V – W u skladu su IEC 60034-8 standardom. Nulta tačka, ako postoji, označena je slovom N.
Spoj na mrežu uz pravilnu faznu sekvencu (L1 – L2 – L3) garantuje da će se osovina obrtati u smeru naznačenom pomoću strelice u blizi osovine.
U slučaju pogrešne fazne sekvence, smer vrtnje osovine može se promeniti zamjenom spoja na stezaljkama U i W.
SPOJ NA POMOĆNU SPOJNU KUTIJU
Motor može imati jednu ili više pomoćnih spojnih kutija
Standardno rješenje podrazumjeva jednu pomoćnu spojnu kutiju koja ima barijeru između stezaljki napojnih krugova (grijači prostora, vanjski ventilator sl.) i stezaljki za mjerno-zaštitini sistem.
Obezbedite da su instrumenti za merenje i nadzor spojeni u skladu sa tehničkom dokmentacijom i proveriti njihov ispravan rad.
Upozorenje! Poduzmite sve neophodne mjere opreza prilikom rada na krugovima koji mogu doći pod napon.
EEx d IIB pomoćna priključna kutija
EEx d IIC pomoćna priključna kutija
LEŽAJEVI
LEŽEJVI PROTIV TRENJA (ležajevi sa kotrljajućim kontaktom)
Ležajevi se pune mazivom od litijevog sapuna prije isporuke. Periodi mirovanja koji traju i po nekoliko mjeseci mogu rezultovati izdvajanjem ulja iz maziva za ležajeve. Demontirajte vanjski poklopac ležaja, i oklonite ostatke maziva i ulja. Dopunite sa svježim mazivom odgovarajućeg tipa i ponovo zatvorite poklopac ležaja.
Nadziranje temperature ležaja Temperaturni senzori će biti podešeni na namjanju vrednost temperature na osnovu testova i radnih uslova. Maksimalne vrednosti koje su preporučene za normalnu radnu temepraturu sa standardnim lubrikantima i temperature okoline 40°C su:
Alarm : 90°C (194°F)
Trip : 100°C (212°F)
Ako se koriste maziva za visoke temperature (npr. za mašine radne temperature klase F) tada se limiti mogu postaviti 10°C (28°F) više. Uskladiti to sa uputstvom za upotrebu.
KLIZNI LEŽAJEVI
Klizni ležajevi se isporučuju bez ulja. Na mašinama sa samoventilirajućim ležajevima, odnosno onim koji nemaju poseban sistem za napajanje uljem, ulje se doprema do ležajeva pomoću uljnih prstenova.
Ako je mašina duže vremena ugašena, tada će rotor potisnuti uljni film između the dijelova ležaja pa će se ležaj isušiti. Stoga, prije okretanja osovine, (čak i rukom) barem 100 to 200 cm³ ulja mora se ručno ubrizgati u svaki ležaj. Ovo se može uraditi uklanjanjem vijčane zaptivke ili ventilaciojskog filtea koji su smešteni na vrhu polopca ležaja i umetanjem levka u otvor. Pazite da koristite odgovarajući tip ulja. Kada ubrizgavate ulje za podmazivanje, obratite pažnju na nivo koji treba biti do polovine okna za kontrolu ulja. Viši nivo nije preporučen jer može doći do curenja ulja kroz brtve tokom rada.
Mašine hlađene vanjskim aksijalnim ventilatorom (HXR ili AMDR-AMDT tipovi) Imaju na N.D.E. strani ventilacijsku cev (sa filterom) koja izlazi iz ventilacionog otvora da bi se izbjegao nadpritisak u kućištu ležaja
Zasebno hlađeni obični ležajevi Ležajevi su povezani na sistem snabdevanja uljem koji se mora pustiti u rad prije stavljanja mašine u pogon i koji mora biti operativan dok se mašina ne ugasi. Maksimalna temperatura ležajeva na ispustu ulja ne smije preći 65°C.
Nadzor temperature ležajeva U slučaju das u dostvljeni, temperaturni senzori će koristiti isti kriterij kao za ležajeve protiv trenja. Maksimalne vrednosti koje su preporučene za normalnu radnu temepraturu sa standardnim lubrikantima i temperature okoline 40°C su:
Alarm : 90°C (194°F)
Trip : 100°C (212°F)
Polaganje uljnih trasa Između spojnog creva ili flanše i sistema za napajanje uljem moraju se postaviti fleksibilne cevi kako bi se ostvarila veza bez prenosa pritiska. Ovo osigurava bolju i nepropusnu vezu, a takođe sprečava oštećenje delova za električnu izolaciju, ako su isti postavljeni. Prije polaganja, hrđa i pesak se moraju ukloniti sa cevi, koja se potom treba oprati inhibiranom hidrohlornom kiselinom i isprati uljem za ispiranje. Inhibitor treba koristiti prema preporukama proizvođača. Trasa za povrat ulja mora imati kontinuiran pad od 5% (= 50 mm na svakih 1000 mm dužine) od spojne flanše na ležaju motora do uljnog spremnika. Ovo je minimalno dozvoljni pad!
Imajte na umu da će se nivo ulja u ležaju povećati ako se ulje kreće presporo u odvodnim cevima. Ovo mpže uzrokovati curenje ulja ili ometanje protoka. U princpu, povratna trasa treba biti što kraća. Slobodni presek treba biti barem jednak preseku ulazne cevi. Ako je mogće, izbegavati krivine i savijanja. Da bi se izbegao rizik od porasta pritiska u ležajevima, ove cevi ne smiju sadržavati dvostruke zavoje ili sifone. Ako je moguće, koristiti specifikacije sa crteža. Ulazne tačke moraju biti postavljene u pravcu toka. Promer cevi mora biti toliko velik da omogući protok ulja pri sledećim brzinama:
:
- Prihvat ulja (puni promer cevi) manje od 1.5 m/sec.
-Povrat ulja (puni promer cevi) manje od 0.17 m/sec.
Da bi se sprečilo formiranje uljne pene, vertikalni padovi > 1 m moraju se izbeći.
Kada zaptivke ležaja imaju sistem za sprečavanje ulaska zraka, tada je potrebno obezbediti kvalitetno ventiliranje kućišta.
Ovo se može ostvartiti samo kroz povratne trase ili putem oduška sa filterom dimenzionisanog da se spreči istjecanje uljnih para.
1) Povratna trasa 2) Odušak
3) Ispust uljnih para
U slučaju sistema sa velikim protokom ulja (npr. sistemi snabdevanja uljem), može biti ekonomski opravdano da se ulje za podmazivanje obnovi za dalju upotrebu. U takvim slučejevima, ulje se mora testirati na hemijska i mehanička svojstva za vreme puštanja u rad. Odgovarajuće tabele sa uputama za testiranje možete dobiti od nas na upit.
PREPORUKE ZA DIZJANIRANJE SISTEMA ZA SNABDEVANJE ULJEM
Uljni tank mora biti opremeljan ispustom za uljne pare kako bi se u tanku stvorio podpritisak Ovaj podpritisak osigurava da ne dođe do porasta pritiska u uljnim trasama i da je kućište ležaja ozračeno. Istovremeno, ulje će biti očišćeno od para i odvojeno od zraka uhvaćenog u ulju.
Uljni tank mora biti opremeljen separatorom kondenza, kao i grijačem, ako vanjska temperatura mže pasti nisko. Pogodna zaštita od unutrašnje korozije će pomoći da se spreči zagađenje uljem.
Trasa povrata ulja mora ući u uljni spremnik iznad nivoa ulja (Var. A). Ako se povratna linija potopi, moraju se obezbediti ozrake kako bi zrak iz ulja mogao izaći van (Var. B).
Trasa dovoda ulja mora biti tako postavljena da u bilo kojem režimu rada ulje ne pada ispod najaniše tačke trase.
Filteri moraju uklanjati čestice veće od 0.040 mm i biti opremeljene magnetnim separatorom. Ako režim rada to zahtejva, postavljaju se izmjenjivi dvostruki filteri koji se mogu mijenjati i čistiti za vrijeme rada bez prekidanja dotoka ulja.
ABB ne može prihvatiti odgovornost za curenje ulja iz ležajeva ili uljnih trasa ako gore navedeni uslovi nisu ispunjeni.
IZOLACIJA LEŽAJEVA
Izolacija ležajeva se radi na zahtjev kupca. Mašine svih veličina se mogu isporučiti sa izolovanim ležajevima na oba kraja i na zahtjev kupca. Detalji o izolaciji ležajeva dati su u posebnom dokumentu “Izolacija ležajeva”, npr. da li ljuska ležaja ili završni oklop jednog ili oba ležaja imaju izolaciju, te da li je predviđeno premoštavanje izolacija u svrhe testiranja.
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Years of experience: 18. Registered at ProZ.com: May 2014.
Electrical engineer with 15 years of experience in power enginnering design, construction, sales and management. At the same time, freelance translator, mainly in field of engineering, electrical and mechanical
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