Results of the analysis of labor organization and measures to improve it.
Technological maps provide a detailed technically sound description of operations for the current repair of equipment at traction substations, substations and substations and must be strictly observed when performing work. They define the categories of work in relation to safety measures, the composition of performers and their qualifications, and set out the basic requirements to ensure the safety of personnel. The number of performers and safety measures when preparing the workplace are specified by the work order (order) issued for the work.
The title of the position of an electrician in this collection is adopted in accordance with the Qualification characteristics and pay grades for positions of managers, specialists and employees according to the industry wage scale (approved by the instruction of the Ministry of Railways dated October 18, 1996 No. A-914u) and the Collection of changes and additions to the qualification characteristics and pay grades labor positions of managers, specialists and employees according to the industry tariff schedule (Moscow, PVC Ministry of Railways of the Russian Federation, 1999). The name of the profession and qualification level of an electrician at a traction substation is according to the Unified Tariff and Qualification Directory of Work and Professions of Workers (ETKS), issue 56 and the Collection of Tariff and Qualification Characteristics of Professions of Workers Employed in Railway Transport (Moscow, PVC Ministry of Railways of the Russian Federation, 1999).
When performing the work provided for in the collection, instruments, tools and accessories are used that are produced by the electrical industry and are designed specifically for work in electrical installations of traction substations. Recommended lists of them are given in each technological map. In addition to the recommended ones, other types of devices with similar or similar characteristics can be used.
Performers must be provided with the necessary tools, instruments and devices that meet the technical conditions. They are cared for by personnel performing basic work.
All operating personnel involved in technological processes must have sufficient experience and pass a safety test.
The limits of numerical indicators given in the collection, in which “up to” is indicated, should be understood inclusive, “not less” - are the smallest.
When this collection is published, the collection “Map of technological processes of capital, current repairs and preventive tests of specific equipment of traction substations of electrified railways”, approved on January 14, 1994 by the Ministry of Railways of the Russian Federation, No. TsEE-2, becomes invalid.
2. Transformers Technological map No. 2.1.
Current repairs of power transformers10000 - 63000 kVA1. Cast
Electromechanic - 1
Electrician of traction substation 4 categories - 1
Electrician of traction substation 3rd category - 1
2. Conditions for performing work
The work is being done:
With stress relief
Alongside
3. Protective equipment, devices, tools, accessories and materials:
Protective helmets, safety belt, ladder, grounding, short-circuits, dielectric gloves, megohmmeter for voltage 1000 and 2500 V, stopwatch, thermometer, level, pump with pressure gauge and hose, wrenches, combination pliers, screwdrivers, scraper, brushes, container for draining sediment, glass containers with a ground stopper for taking oil samples, indicator silica gel, silica gel, transformer oil, CIA-TIM lubricant, white spirit, moisture-oil-resistant varnish or enamel, spare oil indicator glasses, rubber gaskets, cleaning material, rags
4. Preparatory work and permission to work
On the eve of the work, submit an application for the transformer to be taken out for repair.
Check the serviceability and expiration dates of protective equipment, devices, prepare tools, installation devices and materials.
After issuing the work order, the work contractor must receive instructions from the person who issued the work order.
4.4. Operating personnel prepare the workplace. The work foreman checks the implementation of technical measures to prepare the workplace.
Clear the team for work.
The work manager instructs the team members and clearly distributes responsibilities between them.
End of technological art№ 2.2.
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Changing the oil in hydraulic seals of oil-filled bushings A silica gel in moisture-absorbing cartridges (see rns. 2.1.1., Fig. 2. 1.3.) |
The state of silica gel in desiccant cartridges is determined by the color of the indicator silica gel. If the color changes from blue to pink, replace the silica gel in the cartridges and the oil in the water seal. Replace Siliga gel in dry weather, taking the dehumidifier out of operation for no more than one hour. Check the oil level in the hydraulic seal. Replacing silica gel is carried out as follows: disconnect the cartridge from the input, replace the silica gel, having previously cleaned the cartridge of contaminants, replace the oil in the hydraulic seal, attach the cartridge to the input |
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Checking the operating condition of transformer taps and dampers |
Check compliance with the operating position of devices, taps, and dampers. Carry out an inspection to check the oil level in the inputs and tanks of the transformer. Record the readings of thermal alarms, oil level indicators, air temperature, and the position of the switches of all windings |
Note. All operations with oil-filled and bushings for voltage 110-220 kV must be performed together with a RRU specialist.
) on open switchgears, when drawing up construction organization projects (COP) and electrical installation work projects (PPER).
Current transformers of the TFZM and TFRM series (single-phase, electromagnetic, oil, outdoor installation, support type) are designed to transmit information signals to measuring instruments, protection and control devices in alternating current installations.
Current transformers (hereinafter referred to as "transformers"") TFZM 500 B and TFRM 750 A are made in the form of two stages (lower and upper), the rest are single-stage. Transformers 220 - 750 kV have a screen on the expander, and two-stage transformers, in addition, have an additional screen covering the joint of the stages.
The technological map contains instructions for organitions and installation technologies, a list of mechanisms, tools, information on material costs, calculation of labor costs and work schedules.
The map assumes that work related to the installation of transformers is carried out directly at the installation site, at the place of their installation, etc.
All calculated indicators in the map are given for the installation of one group (three phases) of transformers.
Labor costs for setup work, installation schedules andcalculations are not taken into account.
The technological map was developed in accordance with the “Guidelines for the development of standard technological maps in construction”. M., TsNIIOMTP Gosstroy USSR, 1987.
Prohibits to open transformers and take oil samples.
Installation should be carried out with the participation of the chief engineer of the manufacturer.
Technical criteria and controls for operations and processes are given in Table. . Acceptance inspection of mounted transformers is carried out in accordance with SNiP 3.05.06-85. When accepting work, they present documentation in accordance with the list of appendices. .
Removing the transformer from the electric locomotive (the work is done after removing the small removable roof and cooling fans of the traction transformer)
1.1 Disconnect all shunts and busbars from the traction transformer, step changer and instrument cabinet.
1.2 Disconnect cables and low-voltage wires from the substation and the instrument cabinet, having first checked their markings. If there are no markings, restore them; if they are incorrectly marked, re-mark them.
1.3 Unscrew the bolts securing the transformer to the electric locomotive body frame. Remove the mesh fencing.
1.4 Moor the traction transformer with a 30-ton bridge crane and move it to the transformer compartment on a transport trolley
Preliminary tests of the transformer.
2.1 Install the transformer in the test station
2.2 Measure the insulation resistance of all windings in accordance with clause 11.2.1.
2.3 Measure the ohmic resistance of the windings in accordance with clause 11.2.2.
2.4 Test the electrical strength of the insulation of the windings in accordance with clause 11.2.4.
2.5 Perform experiment x.x. similar to clause 11.2.6.: at a voltage of 62.5 V, losses should be no more than 2.3 kW.
During testing, identify possible malfunctions and determine the scope of repairs. If necessary, repair the active part.
Disassembling the traction transformer.
3.1 Install the transformer to the repair position
3.2 Clean the traction transformer from dirt and dust.
3.3 Drain the oil from the traction transformer, step changer and expansion tank.
3.3 Remove the substation, instrument cabinet and oil pumps from the transformer and submit them for repair.
3.4 Remove the BF50/10 gas relay, air dryer, flow indicators, thermostats and expansion tank from the transformer.
3.5 Remove the separating plate.
3.6.Remove the covers of the assembly hatches, disconnect the current transformers and bushings.
3.7 Remove inputs m1-m4.
3.8 Unscrew the bolts securing the bell to the transformer tank.
3.9 Moor with an overhead crane and remove the bell.
3.10. Remove the cooling system.
Repair of the active part of the transformer (magnetic core and windings).
4.1 Check the insulation condition of the accessible turns of the coils, leads, contamination of the surfaces of the windings, magnetic circuit and leads with oil deposits, as well as the dimensions of the cooling channels.
4.2 Check the condition of the fastening, wedging and compression of the windings, the condition and fastening of the insulating gaskets between the coils, the serviceability of the electrical connections, the absence of signs of overheating, overlaps, the absence of deformations and displacements of the coils and gaskets.
4.3 Restore loose fastening of the windings by tightening the pressure bolts or installing wedging inserts made of getinax between the pressure plate and the yoke sheets. Tighten the pressure bolts with a torque wrench with a torque of 12-13 kg/cm. After tightening, secure the bolts with wire.
4.4 Tighten the bolts at the bottom of the tie frame on both sides of the bottom of the tank. If necessary, install a fiberglass gasket between the clamping frame and the magnetic core. The tightening torque of the bolts should be 5-6 kg/cm.
4.5 If there are no breaks, interturn short circuits and satisfactory insulation resistance relative to the housing and other windings, bulging winding coils can be returned to their original position by light blows of a hammer through a wooden spacer.
4.6 Check the insulation resistance of the tie rods in relation to the magnetic circuit with a 1000 V megger.
4.7. Check the serviceability of the grounding of the magnetic core, the serviceability of the fastening of the grounding shunt between the sheets of the magnetic circuit, the absence of traces of heating and melting of the shunt and the iron of the magnetic core.
4.8 Clean the contacts of the 25/12 kV switch, check their pressing and fit, check the fastening of the cables, set the switch to the “25 kV” position.
4.9 Clean the insulating plates of the autotransformer terminals and secondary windings of the transformer from dirt, degrease, inspect, and replace defective ones.
4.10 Inspect current transformers, check fastening, integrity of windings, absence of cracks, melting and other damage.
4.11 Dismantle the inlets on the tank cover, clean, inspect, and replace the seals. Replace bushings with cracks. It is allowed to repair bushings D25, D1 type Kkr37/63O using the manufacturer’s technology in accordance with the Rules for the care of the transformer set.
4.12 Remove oil deposits from the surfaces of the windings, leads, magnetic circuit and cooling channels. The use of wooden scrapers is permitted. Flush the transformer with clean, dry transformer oil.
4.13 Clean the transformer tank, conservator and cooling system from sludge and sediment, rinse with clean, warm, dry transformer oil. Clean the outer part of the coolers from dust and dirt, degrease with gasoline.
4.14 Inspect the inner walls of the tank and its roof, check the color strength of the inner surface. Clean areas with peeling paint and paint with epoxy primer paint. Check the condition of the welding of the installation chambers inside the tank for installing the magnetic rod, the serviceability of the felt gaskets under the legs of the magnetic rod, and the devices for attaching the core to the tank.
4.15 Check the condition of the oil lines, their valves, taps and seals; replace or repair defective ones. Inspect welds, cut out defective ones and restore them.
4.16 The active part of the transformer must be exposed to air for no more than 24 hours at an air humidity of no more than 75%.
Repair of transformer cooling radiators.
5.1 Prepare radiators for testing. Install clamps to prevent deformation. Assemble the flange for compressed air supply. Close the opposite flange tightly.
5.2 Connect the pressure hose with pressure reducing valve to the radiator flange.
5.3 Immerse the radiators in a tank of water heated to 60 0 C.
5.4 Test radiators with an air pressure of 2.5 atm.
5.5 On serviceable radiators, dismantle the testing devices. Wash the radiators with transformer oil and transfer them for assembly.
5.6 Remove the faulty radiator from the radiator set. Install a blank flange on the radiator. Immerse the radiator in a tank of water heated to 60 0 C and test individual pipes with an air pressure of 2.5 atm. Mark the places of defects. Remove the radiator from the device and seal the defective pipes tightly on both sides with tin. No more than 5% of the tubes are allowed to be embedded in one radiator.
5.7 After repair, assemble a set of radiators and repeat tests in paragraphs 5.1.-5.5.
Drying of transformer windings is carried out when the insulation resistance of the windings is below the standardized values or when the active part is exposed to air for more than 24 hours.
6.1 Move the transformer to a drying cabinet.
6.2 Turn on the cabinet heating and, with the cabinet lid slightly open, heat the transformer to a temperature of 85-95 0 C with a temperature increase rate of no more than 60 0 C/hour.
The temperature is controlled by thermoelements installed at 2 points: on one of the coils at the top between the insulation collars and on the plate for the magnetic core tie.
6.3 After the transformer temperature reaches 85-95 0 C, close the cabinet and dry the transformer in a vacuum. Vacuum increase no more than 0.25 atm/hour (0.025 MPa/hour).
After reaching a vacuum of 0.00665-0.000133 atm. (665-13.3 Pa) dry for 28 hours. at a temperature of 85-95 C.
With TR-3, drying in a vacuum of at least 5320 Pa (0.0532 atm) is allowed.
6.4 The end of drying is the moment when the insulation resistance of the windings exceeds the standardized values and practically stops increasing. The condensate output should be no more than 0.5 l/hour.
6.5. Upon completion of drying, stop heating and eliminate the vacuum at a rate of no more than 0.01875 MPa/hour (0.1875 atm/hour).
6.6 After drying, tighten the fastening of the windings with pressure bolts to a torque of 12-13 kgf/m, if necessary, place a gasket made of getinax between the pressure plate and the magnetic core. Tighten and cotter the connecting bolts, tubes, and holders.
6.7 Check the insulation condition of the magnetic core tie rods with a 1000 V megger.
6.8 Move the transformer to the tank for assembly.
6.9 With TR-3, it is allowed to dry the transformer in its own tank by short-circuiting the traction winding. Short-circuit current should not be more than half the rated current of the traction winding.
Transformer assembly.
7.1 Check the insulation resistance of the windings relative to each other and relative to the housing:
high-voltage winding (Do, D1, D25) - 100 MOhm;
traction windings (m1-m4) - 20 MOhm;
heating winding (C1-C2) - 10 MOhm;
auxiliary winding (E-J) - 5 MOhm.
7.2 Assemble the tank: cooling system, bushings, insulating plates, step switch, 25/12.5 switch, current transformers, assembly hole covers, expansion tank.
When assembling, install new seals made of oil-resistant rubber.
7.3 Fill the transformer with oil.
Open the topmost air vent. Fill the tank from the bottom with dry, warm transformer oil, heated to 70 0 C. The temperature of the transformer should be within 60-70 0 C (measure the temperature on the magnetic circuit before assembling the upper part of the tank). Close the air bleeder hole.
When the transformer temperature is less than 60 0 C, it is necessary to preheat the transformer by circulating warm oil between the transformer and the filtering device until the temperature of the transformer and oil is equalized. For heating, set the circulation speed to 450-600 l/hour for 7 hours.
7.4 After installing the BF50/10 gas relay and air dryer, top up the transformer with oil through the expansion tank.
7.5 Bleed air from the tank at 12 points.
7.6 Pump the oil with pumps for 2 hours, then bleed the air again at 12 points.
7.7 Leave the transformer for 2 days, then bleed off the air at 12 points.
Air dryer repair.
8.1 Disassemble the air dryer removed from the transformer.
8.2 Inspect the air dryer parts and replace those that are unsuitable.
8.3 Regenerate drying agent.
Pour the drying agent into a clean lining in a layer of no more than 10 mm.
Heat the drying agent in the drying chamber and dry at a temperature of 120-180 0 C for 3 hours.
The end of drying is a change in color from pink to bright blue.
Brown color indicates the destruction of drying properties as a result of overheating.
The drying agent can be regenerated up to 50 times
8.4 Assemble the air dryer. The oil seal must be transparent.
Fill the air dryer space with a mixture of 80% silica gel (white) and 20% blaugel (bright blue).
8.5.Install the air dryer on the expansion tank and fill the oil seal of the air dryer with transformer oil to the level indicated by the mark on the oil seal.
Repair of gas relay BF50/10/
9.1. To remove the relay from the transformer, after draining the oil from the transformer, unscrew the release bolt at the bottom of the relay housing and release the oil, disconnect the control circuit wires from the terminal strip, disconnect the grounding shunt and remove the relay.
9.2 Remove the internal mechanism from the housing, carefully inspect it, eliminate defects, and assemble the relay.
9.3 Test the electrical strength of the insulation of the relay electrical circuits relative to the housing with and without transformer oil.
The test is carried out with an alternating voltage of 2.5 kV with a frequency of 50 Hz for 5 seconds.
9.4 Check the relay for leaks.
Carry out the check within 20 minutes. With an excess oil pressure of 1 kgf/cm2, there should be no drop in oil pressure observed on the bench pressure gauge, and there should be no oil leakage from the relay.
9.5 Perform a functional test of the relay.
9.5.1 Perform triple control of the action using the control button on the oil-filled relay.
In this case, the stand's signal lamp should light up.
9.5.2 Check the relay operation when the oil level drops.
Inflate air through the control valve. In this case, the stand's signal lamp should light up.
Drain the oil from the relay. In this case, two signal lamps of the stand should light up.
9.6 Test results according to clauses 9.3.-9.5. enter into the journal.
9.7 Place a working relay on the transformer and connect the control circuit wires to the terminal strip in accordance with the diagram.
Testing thermostats.
10.1 Install the thermostat in a bath with transformer oil heated to 60-80 0 C and a control thermometer placed in it.
10.2 Set the thermostat to the maximum temperature (110 0 C).
10.3 Connect the electrical circuit for signaling the thermostat on to terminals 1.3 of the thermostat.
10.4.Smoothly reduce the temperature of the thermostat setting until the alarm is triggered to turn on the thermostat.
10.5. Compare the readings of the control thermometer with the readings of the thermostat scale.
10.6. If the readings of the thermostat and the control thermometer coincide, install the thermostat on the transformer tank.
10.7 If the readings do not match, adjust the thermostat.
Using a screwdriver, secure the adjusting shaft. Unscrew the installation bolt. While holding the axis, set the scale with the mark to the actual temperature at which the thermostat was supposed to operate. Secure the installation bolt.
10.8 After adjustment, test the thermostat again according to paragraphs 10.1.-10.5.
10.9 Connect control circuit wires to the thermostat terminals according to the electrical diagram.
10.10 Adjust the thermostat settings:
01513 — setpoint 80 0 C;
01525 - setpoint 40 0 C;
01526 - setpoint 60 0 C;
01529 - setpoint 20 0 C.
Traction transformer testing.
Transformer testing after SR.
Transformer testing after TR-3.
11.1 Preparatory operations.
11.1.1 Ground the transformer housing.
11.1.2 Turn on the oil pumps and pump the oil for 2 hours.
Let the oil settle for 12 hours.
11.1.3 Carry out an oil analysis in accordance with the Instructions for the use of lubricants on locomotives and MVPS TsT-2635.
11.1.4 Bleed air from insulators, radiators, gas relay, voltage switch.
11.1.5 Check the operation of the PS oil filtration pump and the PS oil heating system.
11.1.6 Check the polarity of the current transformers for protecting the high voltage winding and the correctness of the circuit in the terminal box. Ring the current transformers of the traction windings and heating windings.
11.1.7 Short-circuit and ground all current transformers.
11.2.1 Measure the insulation resistance of all windings relative to the housing and relative to each other with a 2500 V megger.
The insulation resistance must be no less than:
- high-voltage winding - 100 MOhm;
- heating winding - 10 MOhm;
- traction windings - 20 MOhm;
- auxiliary winding - 5 MOhm.
Determine the absorption coefficient (moisture content of the windings)
K = R60 / R15 > 1,
When the measurement temperature is above 15 0 C, recalculate by multiplying the readings by the coefficient from the table
| Temperature difference | 5 0 C | 10 0 C | 15 0 C | 20 0 C | 25 0 C | 30 0 C |
| Coefficient | 1,23 | 1,5 | 1,64 | 2,25 | 2,75 | 3,4 |
11.2.2 Measure the ohmic resistance of the windings using a voltmeter-ammeter method or a DC bridge.
Check the resistance of the autotransformer winding at all positions.
Resistance values should not differ from the nominal values by more than 10%.
Nominal values of winding resistance, MOhm
| m1-m2 | m3-m4 | E-J | E-H | E-G | E-F | C1-C2 | Do-D25 | Do-D1 |
| 1,6 | 1,6 | 1,1 | 0,8 | 0,66 | 0,42 | 46 | 492 | 460 |
Autotransformer winding resistance by position, mOhm
| Pos. | Resistance | Pos. | Resistance | Pos. | Resistance | Pos. | Resistance |
| Do-1 | 19,2 | Do-9 | 98,4 | Do-17 | 210,0 | Do-25 | 364,0 |
Resistance of autotransformer winding coils, Ohm
| Cat. | Resistance | Cat. | Resistance | Cat. | Resistance | Cat. | Resistance |
| 1 | 0,0182 | 4 | 0,0080 | 7 | 0,0086 | 10 | 0,0104 |
At an ambient temperature different from 15 0 C, it is necessary to bring the resistance to 15 0 C according to the formula:
R 15 = R env – , where
R ambient - winding resistance at ambient temperature
environment, Ohm;
t ambient - ambient temperature, 0 C.
11.2.3 Checking the transformation ratio.
Apply high voltage to the winding by placing a Do-PS jumper, voltage 200 V.
Make voltage measurements at all positions of the autotransformer winding and on all other windings with the PS position at 32 positions.
The voltage values must correspond to those indicated in the table
| conclusions | Do-D | m1-m2 | m3-m4 | C1-C2 | E-F | E-G | E-H | E-J |
| Voltage, V | 200 | 8,3 | 8,3 | 24,7 | 1,1 | 1,8 | 2,1 | 2,8 |
| NN | For example, B | NN | For example, B | NN | For example, B | NN | For example, B |
| 1 | 7,4 | 9 | 42,8 | 17 | 82,3 | 25 | 142,8 |
11.2.4 Testing the electrical strength of the insulation of the windings relative to each other and relative to the housing with a voltage of 50 Hz for 1 minute.
Test voltage values:
- HV winding 25 kV (Do, D1, D25) - 52.5 kV;
- heating winding (C1, C2) - 11.2 kV;
- traction windings (m1-m2,m3-m4) - 4.9 kV;
- auxiliary winding (E-J) - 1.54 kV.
The test voltage is applied between the short-circuited winding under test and a grounded tank to which all other short-circuited windings of the transformer are connected.
The transformer is considered to have passed the test if during the tests no breakdown or partial discharges were observed, determined by sound, gas, smoke or instrument readings.
11.2.5 Testing the electrical strength of insulation by induced voltage with double rated voltage of increased frequency 200 Hz for 30 seconds. The test checks the turn insulation of the transformer windings.
A voltage of 2080 V is supplied to terminals m3-m4 of the traction winding, the remaining windings are open, and one terminal of each winding (Do, E, C1, m1) is grounded.
The transformer is considered to have passed the test if no current surges or smoke emission from the expander were observed during the tests.
11.2.6 Idling experience.
Measure losses and no-load current, while checking the condition of the transformer magnetic system. Apply the rated voltage to winding m3-m4, and then 115% of the rated voltage with a frequency of 50 Hz. All
the remaining windings are open, one terminal of each winding is grounded.
The following values of losses and current x.x are allowed.
Uxx=1040 V Ixx=90-120 A Pxx=94-125 kW
Uxx=1200 V Ixx=100-140 A Pxx=120-168 kW
11.2.7 Short circuit experience.
Apply a voltage of 200 V with a frequency of 50 Hz to the Do-D25 winding. The low voltage windings are short-circuited one by one, and the current, voltage and short-circuit power are measured.
Measured short-circuit losses convert to nominal values:
Rn=Rizm*K1*K2, where
Riz - measured short-circuit losses, kW;
K1=Un/Umeas—voltage conversion factor;
K2=In/Imeas – current conversion factor.
By comparing the measured values, reduced to the nominal mode, with the permissible ones, check the correctness of the windings.
If the traction windings are short-circuited, simultaneously check the current transformers protecting the traction windings. If the heating winding is short-circuited, check the heating winding protection current transformers.
| Shorted pins | Transf.current terminals | K=Irev/Itransf |
| m1-m2 | 836-837 | 80 |
11.2.8 Check the insulation resistance of all windings as in paragraph 11.2.1.
11.3.1 Measurement of winding insulation resistance according to clause 11.2.1.
11.3.2 Measurement of ohmic resistance of windings according to clause 11.2.2.
11.3.3 Testing the electrical strength of winding insulation in accordance with clause 11.2.4.
11.3.4 Idling experience according to clause 11.2.6.
Painting the external surfaces of the transformer.
12.1 Paint the cooling system with yellow PF-115 enamel at least 2 times.
12.2 Paint the transformer with PF-115 gray enamel at least 2 times.
12.3 Paint the underbody part of the transformer with black enamel.
Handing over the transformer to the locomotive receiver.
13.1 Fill out the transformer test report.
13.2 Together with the workshop foreman, present the transformer for delivery to the locomotive acceptance person.