Moving called an intersection at one level railway with automobile or urban transport lines. Crossings are an area of increased danger for the movement of railway, road transport, and pedestrians. Equipping crossings with automatic crossing signaling devices (APS) and auto barriers increases the safety of transport operations.
Devices for automatic fencing of crossings have become widespread, which include automatic traffic light alarms with or without automatic barriers and automatic warning alarms, which are supplemented by manual barriers
It is necessary that APS devices meet the following operational requirements:
The crossing alarm was switched on when the train entered the section approaching the crossing in a time sufficient for the advance clearing of the crossing by road transport before the train approached the crossing, was active during the entire time the train was in the approach section and in the crossing area and was turned off only after complete liberation moving train;
automatic crossing fencing devices had backup control, which is carried out by the crossing duty officer;
on the approach side of trains, crossings are fenced off by normally switched off traffic lights with red lights, which are turned on by the crossing duty officer if necessary; It is allowed to use automatic blocking and electrical interlocking traffic lights located near the crossing as barrier traffic lights.
The use of certain devices for automatic crossing fencing is determined by its category. There are four categories of moves.
Crossings of categories I and II, except for crossings with satisfactory visibility conditions for low-traffic areas and access roads, as well as categories III and IV in areas with high traffic speeds passenger trains more than 100 km/h, equipped with automatic traffic lights with auto barriers. In other cases, automatic traffic light signaling without barriers is used.
With automatic traffic light signaling The crossing is protected by special crossing traffic lights with two red lights, which normally (there is no train) do not light up. Traffic lights are installed before the crossing on the right side of the movement of horse-drawn vehicles, their lights are directed towards highway. As the train approaches the crossing, the crossing traffic lights begin to flash alternately. At the same time, an acoustic signal is activated, for which electric bells are installed at crossing traffic lights.
With automatic traffic light signaling with automatic barriers In addition to crossing traffic lights, a barrier is placed in each direction, the beam of which is normally in a vertical position. In the lowered (horizontal) position, the barrier beam is located at a height of 1 - 1.25 m from the road surface. The barrier beam is painted with red and white stripes. It has three electric lights with red lights directed towards the road and located at the base, in the middle and at the end of the beam, and the end light of the barrier is double-sided and continuously lights up towards the railway track in white. The remaining lights flash synchronously with the crossing traffic lights.
Warning alarm serves to provide the crossing duty officer with sound and light signals about the approach of a train. To do this, an alarm panel is installed at the crossing with warning lamps about the approach of a train in an even or odd direction, as well as with lamps for monitoring the lamps and electrical circuits of traffic lights; an electric bell alerting about the approach of a train, which is duplicated by a bell installed outside the premises of the crossing duty officer; sealed button for turning on the security alarm.
To fence crossings with warning alarms, electric or mechanized barriers are used, which are controlled by the crossing duty officer. The normal position of such barriers is closed (except in some cases with particularly heavy traffic).
Barrage alarm at crossings it is used to give the train a signal to stop at emergency situation on the move. Only guarded crossings are equipped with barrier alarms. Special traffic lights and track blocking traffic lights or station traffic lights can be used as barrier lights if they are no more than 800 meters away from the crossing and the crossing is visible from where they are installed. Special obstruction traffic lights, usually mast-mounted, with normally unlit red lights, have a different shape from ordinary traffic lights.
Barrier traffic lights are installed on the right side of the train movement at a distance of 15 to 800 m from the crossing, ensuring the visibility of the traffic light at a distance not less than the braking distance of the train at its maximum speed and emergency braking. In areas with automatic blocking, barrier traffic lights are linked to the automatic blocking signals closest to the crossing, which overlap with a prohibitory indication with the ALS codes turned off when the barrier traffic lights are turned on. In areas without automatic blocking, if it is impossible to ensure visibility of the barrier traffic light, within the distance of the train braking distance, a warning traffic light of the same type is placed, on which a yellow light is turned on when the red light is turned on at the barrier traffic light.
Equipment and equipment used only in crossing signaling include crossing traffic lights, auto barriers and crossing alarm control panels.
Appearance A crossing traffic light with two signal heads and a “Beware of the train” sign in the form of a single cross is shown in Fig. 8.2. Visibility range of flashing crossing traffic lights on a clear day sunny weather must be at least 215 m with a visibility angle of at least 70°.
Vertical-rotating automatic (electric) barriers are designed for crossings, operating in automatic and non-automatic modes with a barrier beam length of 4 and 6 m (Fig. 8.3). The time for complete opening (closing) of the barrier should not exceed 7-9 s.
Electric track circuits are used to notify trains when they are approaching. In areas with automatic blocking, automatic blocking rail chains are used. In areas without automatic blocking, depending on the type of traction and reliability of power supply, rail circuits of direct or alternating current with a frequency of 50 or 25 Hz can be used. At crossings, rail circuits superimposing a tonal frequency of 1500-2000 Hz are used, which allow organizing the approach to the crossing regardless of the placement of automatic blocking traffic lights and work with all types of traction. Maximum length such a rail chain is 1500 m.
Crossing traffic lights and auto barriers are controlled according to the scheme (Fig. 8.5). When a train enters the section approaching the crossing, one of the approach detectors is de-energized Emergency or NP in accordance with the direction of movement of the train and the power circuit of the turning on relay is turned off IN.
After the deceleration time has expired, the relay releases IN its repeater is de-energized PV, the contacts of which turn off the power circuit of the control relay U and relay VM(not shown in the diagram) and the power supply circuit for the bells of the auto barriers is turned on. The bells will be turned on until the barrier bar is completely lowered, when their power circuit is opened by the autoswitch contacts.
Relay contacts U the lamps of crossing traffic lights and the lamps on the bars of car barriers are turned on. Relay U/(connected in series with relay U) includes a flashing light circuit containing a pendulum transmitter and relay M, thanks to which the lamps of crossing traffic lights 1L and 2.77 and lamps on the barriers bars 1LSh And 2LSh start flashing. Lamp ZLSH at the end of the beam it burns continuously.
Relay VM has a release time of approximately 14-16 s, which is necessary so that a car entering the crossing at the moment the alarms are turned on has time to release it. After lowering the armature, the relay VM The barrier closing relay is excited ZSH and the barrier opening relay is de-energized OSH. Relay contacts ZSH the circuit of the armature and the excitation winding of the barrier drive motor is closed, and a current of such polarity is supplied to the excitation winding that ensures the lowering of the beam. The engine is turned off by the barrier autoswitch contacts when the beam reaches a horizontal position.
After the train passes through the crossing, the corresponding relay is excited Emergency or NP and a circuit is created to excite the relay CT, which has a delay in closing the front contact of about 8-16 s, achieved by the presence of a thermoelement. Relay connection diagram IN And /<Т построена таким образом, что возбуждение реле IN only possible with a time delay. This prevents the crossing from opening in the event of a short-term loss of the shunt on the track circuit of the approach section. When the relay is energized IN The thermocouple turns off and the relay IN And CT self-blocking through its front contacts.
After energizing the relay IN relay power circuits turn on PV, VM. This de-energizes the relay ZSH and the relay is excited OSH, switching the polarity of the motor excitation winding power supply with its contacts. When the barrier beam takes a vertical position, the autoswitch contacts turn off the engine and the relay is energized Uh, which turns off the signal lights of crossing traffic lights and barriers.
Controlling a crossing alarm is no different from controlling auto barriers from the control panel, but in this case using buttons 3 (closing) and ABOUT(opening) the effect is carried out directly on the relay PV.
To temporarily hold the barrier beam in a vertical position, the attendant must press the button B on the panel, which turns off the relay power circuit ZSH. Relay contact 3 in this circuit prevents the barrier from opening with a pushbutton B. Relay AS And BS turn on the motor armature chains when raising or lowering the barrier beam. Double winding relays JSC And IN monitor the serviceability of crossing traffic light lamps in the on and off states. The lights at obstruction traffic lights are lit by the ZS button, when pressed the relay is de-energized ZG, which turns on the rear contacts of the traffic light lamps.
Devices crossing alarm and auto barriers are powered from an alternating current network through rectifiers of the VAK-13M type, connected according to a continuous charging circuit with a rechargeable battery used for backup power. The signal lamps are powered by an alternating current from the signal transformer, the presence of which is controlled by an alarm relay. When the AC power is turned off, the emergency relay de-energizes and switches power to the lamps to the battery.
Radio relay communication.
Radio relay communication systems(RRS) have also found wide application in terrestrial radiotelephony and, in particular, in radio communications in railway transport. The stages of development of RRS on railways can be traced using the example of the construction and operation of a radio relay line on the route of the Great Moscow Circular Railway, the length of which is 420 km.
RRLs are a chain of transceiver stations (terminal, intermediate, node), installed at a line-of-sight distance (40 - 70 km in the frequency ranges up to 6 - 8 GHz and several km in the ranges 30 - 50 GHz) with an antenna height of 60-100 m ).
Terminal stations are installed at the extreme points of the communication line and contain modulators and transmitters in the direction of signal transmission and receivers with demodulators in the direction of reception. For reception and transmission, one antenna is used, connected to the reception and transmission paths using an antenna splitter (duplexer), or two antennas.
Modulation and demodulation of signals is carried out at one of the standard intermediate frequencies (70 – 1000 MHz). In this case, modems can work with transceivers using different frequency ranges. Transmitters are designed to convert intermediate frequency signals into the microwave operating range, and receivers are designed to inversely convert and amplify intermediate frequency signals.
There are RRL systems with direct modulation of microwave (super high frequency) signals, but they have limited distribution.
RRL classification
Two types of RRL: line of sight and tropospheric.
By purpose: intercity trunk, intrazonal, local RRL.
By frequency range: frequency bands are allocated in the region of 2, 4, 6, 8, 11 and 13 GHz. Research is underway to create RRL at frequencies of 18 GHz and higher. But the HF signal is greatly attenuated in precipitation.
According to the method of compaction and type of modulation: with PDK, with VRK and analog pulse modulation, digital RRL.
In terms of throughput: high-capacity RRL (more than 100 Mbit/s), medium-capacity for zonal communications - 60...300 k (10-100 Mbit/s), low-capacity for local and departmental communications. Multiple trunks are used to increase throughput.
Radio relay lines on the railway provide the organization of trunk, road and department connections. An approximate diagram of a railway radio relay line includes 3 radio channels. Intermediate points of the main and road trunks are located at a distance of 30 - 50 km, while industrial points with dedicated canals are built near railway stations, where road departments and departments are located, as well as junction and large stations. Industrial stations with separate separation shaft channels are located at all railway stations at a distance of 5 to 25 km. Various types of signals can be transmitted through a communication channel: telephone (conversation), sound or television broadcasting, telegraph, telecontrol, etc.
The separation equipment in combination with the RRL microwave transmitting and receiving equipment forms a broadband path, or communication trunk, through which the group signal generated in the separation equipment is transmitted. At RRLs, to increase their economic efficiency and capacity, several parallel operating radio channels are organized, equipped with the same type of transmitting and receiving radio equipment. The equipment of adjacent trunks operates at different carrier frequencies, but on common antennas. It is connected to the antenna-feeder system through isolation filters (they are not shown in Fig. 22.2). On modern lines, up to six to eight trunks or more are organized, used for multi-channel telephony, television, redundancy, etc. The capacity of the telephone trunk is selected from 24 to 1920 channels
On the RRL shown in Fig. 22.2, to transmit multichannel telephony signals, telephone trunks with a capacity of 60 channels each are organized. Television programs (video and audio signals) are transmitted in a special television trunk ///. In this case, the video signal (image) and the audio signal can be transmitted together in one television trunk or separately when the audio signal is transmitted in one of the telephone trunks.
The main equipment of radio relay stations includes transmitting and receiving radio equipment (operating in the microwave range), antenna-feeder devices, separation equipment, power supply devices, to auxiliary equipment- devices for service communication, telecontrol, telesignaling, control and measurement.
The equipment of radio relay stations is installed in a technical building, and the antennas are installed on masts or towers. The height of the antennas should ensure direct visibility between them. Depending on the terrain, the height of the masts or towers reaches 80 m or more. To reduce the length of high-frequency feeders between the radio equipment and the antenna, the receiving and transmitting equipment is placed in the top floor of a monolithic reinforced concrete tower, and antenna devices are placed on its roof. Power equipment is installed in the lower floors of the tower.
Railway crossings are the intersection of highways and railway tracks at the same level. Moving places are considered high-risk objects. The main condition for ensuring traffic safety at crossings is the following condition: railway transport has an advantage in traffic over all other modes of transport.
Depending on the intensity of railway and road transport traffic, as well as depending on the category of roads, crossings are divided into four categories. Crossings with the highest traffic intensity are assigned category 1. In addition, category 1 includes all crossings in areas with train speeds of more than 140 km/h.
Moving happens adjustable And unregulated. Regulated crossings include crossings equipped with crossing signaling devices that notify vehicle drivers about the approach of a train crossing, and/or serviced by employees on duty. The possibility of safe passage through unregulated crossings is determined by the driver of the vehicle independently in accordance with the Road Traffic Rules of the Russian Federation.
The list of crossings serviced by the employee on duty is given in the Instructions for the operation of railway crossings of the Russian Ministry of Railways. Previously, such crossings were briefly called “guarded crossings”; according to the new Instructions and in this work – “moving with an attendant” or “attended moving”.
Crossing alarm systems can be divided into non-automatic, semi-automatic and automatic. In any case, a crossing equipped with a crossing alarm is protected by crossing traffic lights, and a crossing with a man on duty is additionally equipped with automatic, electric, mechanized or manual (horizontally rotating) barriers. At crossing traffic lights There are two red lamps located horizontally, which burn alternately when the crossing is closed. Simultaneously with the switching on of crossing traffic lights, acoustic signals are switched on. In accordance with modern requirements, at certain crossings without an attendant, the red lights of crossing traffic lights are supplemented white-moon fire. When the crossing is open, the white-moon light lights up in a flashing mode, indicating the serviceability of the devices; when closed, it does not light. When the white-moon light is extinguished and the red lights are not burning, vehicle drivers must personally ensure that there are no approaching trains.
The following are used on Russian railways: types of crossing alarms :
1. Traffic light signaling. Installed at crossings of access roads and other tracks where approach areas cannot be equipped with rail chains. A prerequisite is the introduction of logical dependencies between crossing traffic lights and shunting or specially installed traffic lights with red and moon-white lights that serve as barriers for railway rolling stock.
At crossings with an attendant, the crossing traffic lights are turned on by pressing a button on the crossing signaling panel. After this, the red light at the shunting traffic light goes out and the moon-white light turns on, allowing the movement of the railway rolling unit. Additionally, electric, mechanized or manual barriers are used.
At unmanned crossings, crossing traffic lights are supplemented by a white-lunar flashing light. The closing of the crossing is carried out by workers of the drafting or locomotive crew using a column installed on the mast of the shunting traffic light or automatically using track sensors.
2. Automatic traffic light signaling.
At unattended crossings located at hauls and stations, crossing traffic lights are controlled automatically under the influence of a passing train. Under certain conditions, for crossings located on a stretch, crossing traffic lights are supplemented with a white-lunar flashing light.
If the approach section includes station traffic lights, then their opening occurs after the crossing is closed with a time delay that ensures the required notification time.
3. Automatic traffic light signaling with semi-automatic barriers. Used at serviced crossings at stations. The closing of the crossing occurs automatically when a train approaches, when setting a route at the station if the corresponding traffic light enters the approaching section, or forcefully when the station duty officer presses the “Closing Crossing” button. The lifting of the barrier bars and the opening of the crossing is carried out by the crossing duty officer.
4. Automatic traffic light signaling with automatic barriers. It is used at serviced crossings on stretches. Crossing traffic lights and barriers are controlled automatically.
In addition to the listed devices, warning alarm systems are used at stations. At warning alarm The crossing duty officer receives an optical or acoustic signal about the approach of a train and turns on the technical means of fencing the crossing. After the train has passed, the attendant opens the crossing.
Classification of crossings and fencing devices
Railway crossings are the intersection of highways and railway tracks at the same level. Moving places are considered high-risk objects. The main condition for ensuring traffic safety is the following condition: railway transport has an advantage in traffic over all other modes of transport.
Depending on the intensity of railway and road transport traffic, as well as depending on the category of roads, crossings are divided into four categories. Crossings with the highest traffic intensity are assigned category 1. In addition, category 1 includes all crossings in areas with train speeds of more than 140 km/h.
Moving happens adjustable(equipped with crossing signaling devices notifying vehicle drivers about the approach of a train crossing, and/or served by employees on duty) and unregulated. The possibility of safe passage through unregulated crossings is determined by the driver of the vehicle.
The list of crossings serviced by the employee on duty is given in the Instructions for the operation of railway crossings of the Russian Ministry of Railways. Previously, such crossings were briefly called “guarded crossings”; according to the new Instructions and in this work – “moving with an attendant” or “attended moving”.
Crossing alarm systems can be divided into non-automatic, semi-automatic and automatic. In any case, a crossing equipped with a crossing alarm is protected by crossing traffic lights, and a crossing with a man on duty is additionally equipped with automatic, electric, mechanized or manual (horizontally rotating) barriers. At crossing traffic lights There are two red lamps located horizontally, which burn alternately when the crossing is closed. Simultaneously with the switching on of crossing traffic lights, acoustic signals are switched on. In accordance with modern requirements, at certain crossings without an attendant, red lights are supplemented white-moon fire. When the crossing is open, the white-moon light lights up in a flashing mode, indicating the serviceability of the APS devices; when closed, it does not light. When the white-moon lights are extinguished and the red lights are not burning, vehicle drivers must personally ensure that there are no approaching trains.
The following are used on Russian railways: types of crossing alarms :
1. Traffic light signaling. Installed at crossings of access roads and other tracks where approach areas cannot be equipped with rail chains. A prerequisite is the introduction of logical dependencies between crossing traffic lights and shunting or specially installed traffic lights with red and moon-white lights that perform the functions of a barrier.
At crossings with an attendant, the crossing traffic lights are turned on by pressing a button on the crossing signaling panel. After this, the red light at the shunting traffic light goes out and the moon-white light turns on, allowing the movement of the railway rolling unit. Additionally, electric, mechanized or manual barriers are used.
At unmanned crossings, crossing traffic lights are supplemented by a white-lunar flashing light. The closing of the crossing is carried out by workers of the drafting or locomotive crew using a column installed on the mast of the shunting traffic light or automatically using track sensors.
2. Automatic traffic light signaling.
At unattended crossings located at hauls and stations, crossing traffic lights are controlled automatically under the influence of a passing train. Under certain conditions, for crossings located on a stretch, crossing traffic lights are supplemented with a white-lunar flashing light.
If the approach section includes station traffic lights, then their opening occurs with a time delay after the closing of the crossing, providing the required notification time.
3. Automatic traffic light signaling with semi-automatic barriers. Used at serviced crossings at stations. The closing of the crossing occurs automatically when a train approaches, when setting a route at the station if the corresponding traffic light enters the approaching section, or forcefully when the station duty officer presses the “Closing Crossing” button. The lifting of the barrier bars and the opening of the crossing is carried out by the crossing duty officer.
4. Automatic traffic light signaling with automatic barriers. It is used at serviced crossings on stretches. Crossing traffic lights and barriers are controlled automatically.
In addition, warning alarm systems are used at stations. At warning alarm the crossing duty officer receives an optical or acoustic signal about the approach of a train and, in accordance with this, turns on and off the technical means of fencing the crossing.
Approach Section Calculation
To ensure unimpeded passage of the train, the crossing must be closed when the train approaches for a time sufficient for it to be cleared by vehicles. This time is called notification time and is determined by the formula
t and =( t 1 +t 2 +t 3), s,
Where t 1 – time required for the car to cross the crossing;
t 2 – equipment response time ( t 2 =2 s);
t 3 – guarantee time reserve ( t 3 =10 s).
Time t 1 is determined by the formula
, With,
Where ℓ n – crossing length equal to the distance from the crossing traffic light to a point located 2.5 m from the opposite outer rail;
ℓ р – estimated length of the car ( ℓ p =24 m);
ℓ o – distance from the place where the car stops to the crossing traffic light ( ℓ o =5 m);
V p – the estimated speed of the vehicle through the crossing ( V p =2.2 m/s).
The notification time is at least 40 seconds.
When a crossing is closed, the train must be at a distance from it, which is called estimated length of the approach section
L p =0.28 V max t cm,
Where V max – the maximum established speed of trains on a given section, but not more than 140 km/h.
The approach of a train to a crossing in the presence of an AB is detected using existing automatic blocking control centers or using track overlay circuits. In the absence of AB, the areas approaching the crossing are equipped with track circuits. In traditional AB systems, the boundaries of the track circuits are located at the traffic lights. Therefore, the notification will be transmitted when the head of the train enters the traffic light. The estimated length of the approach section may be less or greater than the distance from the crossing to the traffic light (Fig. 7.1).
In the first case, the notification is transmitted over one approach section (see Fig. 7.1, odd direction), in the second - over two (see Fig. 7.1, even direction).
Rice. 7.1. Areas approaching the crossing
In both cases, the actual length of the approach section L f is more than calculated L p, because notification of the approach of a train will be transmitted when the head of the train enters the corresponding DC, and not at the moment it enters the calculated point. This must be taken into account when constructing crossing signaling schemes. The use of tonal RCs in AB systems or the use of superposition track circuits ensures equality L f = L p and eliminates this disadvantage.
Significant operational disadvantage of all existing automatic crossing alarm systems (AP) is fixed length of approach section, calculated based on the maximum speed on the section of the fastest train. On a fairly large number of sections, the maximum established speed of passenger trains is 120 and 140 km/h. In real conditions, all trains travel at lower speeds. Therefore, in the vast majority of cases, the crossing is closed prematurely. Excessive time of the closed state of the crossing can reach 5 minutes. This causes delays for vehicles at the crossing. In addition, drivers of vehicles have doubts about the serviceability of the crossing alarm, and they may start driving when the crossing is closed.
This drawback can be eliminated by introducing devices that measure the actual speed of the train approaching the crossing and forming a command to close the crossing taking into account this speed, as well as the possible acceleration of the train. A number of technical solutions have been proposed in this direction. However, they did not find practical application.
Another disadvantage AP systems are an imperfect security procedure in case of an emergency at a crossing(a stopped car, a collapsed load, etc.). At crossings without an attendant, traffic safety in such a situation depends on the driver. At serviced crossings, the duty officer must turn on the traffic lights. To do this, he needs to turn his attention to the current situation, evaluate it, approach the control panel and press the appropriate button. It is obvious that in both cases there is no efficiency and reliability in detecting an obstacle to the movement of a train and taking the necessary measures. To solve this problem, work is underway to create devices for detecting obstacles at crossings and transmitting information about this to the locomotive. The task of detecting obstacles is implemented using a variety of sensors (optical, ultrasonic, high-frequency, capacitive, inductive, etc.). However, existing developments are not yet technically advanced enough and their implementation is not economically feasible.
Railway crossings are places where railways and roads (tram tracks, trolleybus lines) intersect at the same level and, depending on operating conditions, are equipped with one of the following devices: automatic traffic light signaling; automatic traffic light signaling with automatic barriers; automatic warning alarm with non-automatic barriers.
With automatic traffic light signaling, a crossing on the side of the highway is fenced with two crossing traffic lights, each of which has two signal heads with red filters and an electric bell. When the crossing is open, no signals are given; when closed, light (two alternately flashing red lights) and sound (loud bell ZPT-12 or ZPT-24) signals are given.
At crossing traffic lights, you can also install a third head, which signals with a moon-white light that the crossing is open.
With automatic traffic light signaling with automatic barriers, the crossing from the side of the highway is additionally fenced with a barrier bar. When the crossing is open, the barrier beam is in a vertical position; when closed, it is in a horizontal (barrier) position.
The barrier beam is painted with red and white stripes and is equipped with three electric lights with red glass, located at the end, in the middle, at the base of the beam and directed towards the road. The end light is double-sided and also has clear glass.
A lowered barrier beam signals three red lights towards the road and a white light towards the railway. In this case, the end light lights up with a continuous fire, the other two flash alternately.
When the crossing is closed, the barrier beam is lowered 4-10 seconds after the alarm starts working. When the beam is in a horizontal position, the lights on the crossing traffic light and beam continue to light, and the electric bell turns off.
Automatic barriers are also equipped with devices for non-automatic control, including buttons located on the control panel.
If the automatic control system is damaged, the barriers go into the blocking position. At crossings equipped with warning alarms, electric or mechanized barriers, controlled by the crossing duty officer, are used as fencing means. Guarded crossings are also equipped with barrier traffic lights, which are used to signal the train to stop in the event of an emergency at the crossing.
Depending on the category of crossing, speed and traffic intensity of trains and vehicles, the following crossings are used: unguarded with automatic traffic light signaling; guarded with automatic traffic light alarm and automatic barriers; guarded with an alarm system and non-automatic barriers (electric or mechanized). In the last two types of crossings, barrier signaling is also used.
This barrier is designed to automatically block traffic on a crossing when a train approaches it.
Automatic barriers are made with a wooden (or aluminum) beam 4 m long or a wooden folding beam 6 m long and installed on a standard traffic light concrete base. The barrier (Fig. 1) consists of the following main components: electric drive mechanism 1 and mechanism cover 5, barrier beam 2, signaling device 3, counterweight 4, concrete base 6.
Rice. 1. Automatic barrier
Technical characteristics of the automatic barrier
DC motor type SL-571K
Net power, kW 0.095
Voltage, V 24
Rotation speed, rpm 2200
Time for raising or lowering the beam, s 4-9 Current in the electric motor circuit, A, no more than:
when lifting beam 2.5
» work on friction 8.4
Angle of rotation of the beam in the vertical plane, deg 90 Dimensions of the barrier, mm, assembled with beam length, m:
4 4845ХП05Х2750
6 6845X1105X 2750
Weight of barrier, kg, complete (without foundation) with beam length, m:
4 512
6 542
Installation dimensions of the mechanism, mm 300X300
To prevent damage to the lowered beam in the event of an accidental collision with a vehicle, there is a special device that allows the beam to be displaced relative to its axis by an angle of 45° upon impact. The beam is returned to its original position manually.
If there is no power supply, the beam is transferred from a closed position to an open position by lifting it by hand, with the beam first being removed from the locked position by rotating the clutch.
Automatic barrier SHA. The SHA barrier is designed to block traffic on a crossing when a train approaches it. Depending on the length of the beam, there are options for auto barriers - SHA-8, SHA-6, SHA-4.
Technical characteristics of the SHA-8 auto barrier
Type of DC electric motor MSP-0.25, 160 V » solenoid electromagnet ES-20/13-1.5
Time for raising the beam by an electric motor and time for lowering the beam under the influence of gravity, s 8-10
Current in the electric motor circuit, A, no more: when lifting the beam 3.8 "working on friction 4.6-5
Voltage on the solenoid brake electromagnet coil to reliably hold the beam in a vertical position, V 18+1
Working stroke of the pusher contactor, mm 8+1 Length of the barrier beam from the axis of rotation, mm 8000+5
Diameter of the hole for cable entry, mm 30±0.5 Installation dimensions of the mechanism, mm 300X300
Angle of rotation of the beam in the plane, degrees:
vertical 90
horizontal, no more than 0±90
Height of beam axis above foundation, mm 950 Dimensions in closed position, mm:
length 8875±35
width 735±5
height (above the foundation) 1245±5
Weight, kg, over 610±5
» counterweight, kg 120±5
Barriers ША-6, ША-4 with beam length (6000±5) «(4000+5) mm have length (6760± ±5) and (4760±5) mm, respectively, weight (492±5) and (472± 5) kg. The remaining characteristics of the SHA-8, SHA-6 and SHA-4 auto barriers are the same.
Automatic barriers are vertically rotating and consist of the following main components: an electric drive mechanism, a barrier bar, a magnetic brake, a fixing device and a shock absorber.
The fixing device for the fracture of auto barriers eliminates the possibility of lateral rotation of the beam with a force applied at the end of the beam of at least 295 N for ShA-8, 245 N for ShA-6, 157 N for ShA-4. This force is adjusted by preloading the spring.
The shock absorber provides shock mitigation when the beam approaches extreme positions, pushing out when lowering, and also fixes the beam in a horizontal position when the brake electromagnet is de-energized. The sag of the end of the beam should not exceed 280 mm for ША-8; 210 mm - for ША-6; 140 mm - for ША-4.
Reliable holding of the beam in a vertical position is ensured by the electromagnet of the solenoid brake. It is possible to move the beam from a closed position to an open one manually (using a handle), and fix the bracket with the beam in vertical, horizontal positions and at an angle of 70° using the bracket lock.
The lowering time of the beam is regulated by the resistance in the armature circuit of the electric motor.
Crossing traffic lights are used to provide flashing red, moon-white and sound signals to warn vehicles and pedestrians that a train is approaching a crossing. Crossing traffic lights with two and three signal heads, cross-shaped and semi-cross-shaped indicators with reflective colorless lenses, and a direct current electric bell ZPT-24 or ZPT-12 are used.
Mounting traffic light heads allows you to change the direction of the light beam in the horizontal plane by an angle of 60°, in the vertical plane by an angle of ±10°.
Traffic light heads use lens sets of dwarf lens traffic lights (with ZhS12-15 lamps), the luminous intensity of which without a diffuser is at least 500 cd. The visibility range of a red flashing signal on a sunny day along the optical axis of the traffic light head must be at least 215 m, at an angle of 7° to the optical axis - at least 330 m. The visibility angle of the signal in the horizontal plane is 70°.
The following types of crossing traffic lights exist: II-69 - for single-track sections, with two signal heads, a cross-shaped indicator; 111-69 - for single-track sections, with three signal heads, a cross-shaped indicator; II-73 - for two or more sections of track, with two signal heads, cross-shaped and semi-cross-shaped indicators; 111-73 - for two or more sections of track, with three signal heads, cross-shaped and semi-cross-shaped indicators.
Dimensions of crossing traffic lights: II-69, 111-69 - 680X1250X2525 mm; 11-73, 111-73 - 680X1250X2872 mm; weight of traffic lights: II-69 - 110 kg; 111-69 - 130 kg; II-73 and 111-73 - 138 kg.
The crossing alarm panel is designed to control electric and auto barriers installed at crossings. Structurally, the shield is made in the form of a panel on which seven buttons and 16 light bulbs are placed (Table 13.1). The panel is suitable for outdoor installation on a separate rack, the side wall of a relay cabinet or the outer wall of the moving duty officer's room. To protect the panel from precipitation, a visor is provided on the shield frame.
Shield dimensions 536X380 mm; weight without fastening elements 20.2 kg, with fastening elements - 29.4 kg.
Table 1. Purpose of panel buttons and lamps
Name |
Purpose |
Closing |
Switching on crossing traffic lights and closing barriers |
Opening |
Turning off crossing traffic lights and opening barriers |
Turning on the barrier |
Turning on the barrage alarm |
Maintenance |
Maintaining barrier bars in the upper position while maintaining flashing lights at crossing traffic lights |
Turn on the call |
Turning off the alarm bell for crossing warning alarms |
Control of odd and even shunting traffic lights installed to fence crossings on the access road |
|
White and red: |
|
odd approximation |
Signaling for approaching trains in odd directions |
even approximation |
The same in an even direction |
Serviceability check: |
|
Traffic lights |
signal lamps for crossing traffic lights |
set of flashing devices |
|
Zagraditelny 31 |
barrier and warning lamps |
Zagraditelny 32 |
traffic lights connected to them |
Two white llamas |
|
shunting traffic light lamps |
|
Monitoring the voltage in the main and backup power networks at a moving installation |
Electric bells ZPT-12U1, ZPT-24U1, ZPT-80U1.
Rice. 2. Electrical circuits of bells ZPT-12U1, ZPT-24U1 (a) and ZPT-80U1 (b)
1 Tolerance ±15%. 
Electric bells (Table 2) are intended for acoustic signaling at railway crossings and in various stationary railway devices. The bells have a closed structure that houses the electromagnetic system (Fig. 2). Calls provide clear sound that can be heard at a distance of at least 80 m from the call.
Table 2. Electrical characteristics of PTA calls
Call |
Supply current |
Supply voltage, V |
Current consumption, mA, no more |
Frequency, |
Coil resistance1, Ohm |
Constant |
|||||
Variable |
The ambient temperature when using calls should be from -40 to 55 °C. Dimensions 171X130X115 mm; weight 0.97 kg.
DC calls. DC bells are designed for acoustic signaling of blown fuses, control of switches blown and other purposes in signaling and communication devices.
The electrical characteristics of the bells are given below:
Each bell has a spark arresting capacitor connected in parallel with the breaking contact.
A bell with an operating voltage of 3 V starts ringing at a voltage of 1.5 V. The sound strength created by DC bells is at least 60 dB. Bells must be used at air temperatures from 1 to 40 °C. Bell diameter 80 mm; height 50 mm; weight 0.26 kg.
To carry out technological processes when servicing crossing signaling devices and car barriers, you must have a Ts4380 ampere-voltmeter, various kinds of tools and materials. The operation of automation devices should be checked both when the train passes through the crossing and when turned on from the control panel. In sections with large train intervals, automation devices can be switched on by shunting the track circuit of the approach section in the absence of trains.
The operation of automation devices at crossings is checked by an electrician and an electrician once every two weeks. At the same time, they check: the condition and adjustment of the commutator contacts and electric motor brushes; electric motor current when operating on friction; interaction of electric drive parts when opening and closing the barrier; the presence of a lubricant for the rubbing parts of the electric drive; proper operation of sound signals; visibility of crossing traffic lights and lamps on bars; frequency of flashing lights of crossing traffic lights; closing and opening barriers from the control panel; condition of contact springs and drive installation.
In the electric drive, the gearbox, auto-switch, contact block, installation, friction and shock-absorbing clutches are checked. An internal check of the electric drive, including cleaning and lubrication, should be carried out with the barriers closed. To prevent the bars from lifting, it is recommended to place a thin insulating plate between the working contacts through which the electric motor is turned on during the test.
Sound signals are checked while the crossing alarm is operating. With auto- and electric barriers, the bells on the masts of crossing traffic lights should start ringing simultaneously with the turning on of the traffic light alarm and turn off when the barrier beam drops to a horizontal position and the electric drive contacts included in the bell circuit open. For traffic lights without barriers, the bells must ring until the crossing is completely cleared by train. In pulsed power mode, calls should operate with a number of (40±2) switchings per minute.
The electrician must check the operation of all buttons installed on the panel, except for the “Enable the barrier” button. During the inspection, the crossing attendant pushes and pulls buttons, and the electrician observes the operation of the devices, paying special attention to those buttons that the crossing attendant would not normally use.
The operation of the “Close” button at auto barriers is checked in the absence of trains in the approach section. Pressing the “Close” button should turn on the traffic light and sound alarms and close the barriers. When the "Close" button is pulled, the alarm should turn off and the barriers should open.
The condition of the devices and installation of sound and light alarms, as well as the electric drive of the barrier with complete disassembly into individual components, is checked by an electrician together with an electrician once a year.
After disassembling the electric drive, the inside of the housing is cleaned of rust with a metal brush; All characteristics of the electric motor are checked separately, and if necessary, the electric drive is taken to remote workshops. When checking devices and installation of sound and light alarms, the state of the bells is determined by opening the installation leading to them. Carry out internal and external checks of the condition of the heads of crossing traffic lights, lights of barrier bars of barriers.
Once a year, a senior electrician, together with an electrician, carefully checks the operation of automation devices at crossings and determines the need to replace individual components.
At places where railway tracks and roads intersect at the same level, railway crossings.
Depending on the intensity of train and vehicle traffic, crossings are divided into 4 categories. TO first category These include crossings with the most intense train and car traffic. Crossings on inactive lines and with light vehicle traffic are classified as fourth category.
Moving happens adjustable And unregulated.
TO adjustable include crossings equipped automatic crossing alarm devices, notifying drivers about the approach of a train, and on lines with intense or high-speed train traffic - also barrier devices, excluding the departure of vehicles to the crossing when a train approaches it. There are regulated transfers protected And unguarded.
Moving categories 1 and 2 must be guarded. served duty worker and equipped barriers, and barrier traffic lights. Crossing duty officers have radio communication with train drivers, as well as direct telephone communication with duty officers at nearby stations, and with dispatch centralization, with the train dispatcher.
They operate fully automatically and are usually not equipped with barriers.
This includes crossings that are not equipped with any automatic crossing signaling devices. Such crossings are found only on inactive lines, access roads of industrial enterprises, industrial areas, etc.
To ensure traffic safety at railway crossings, the following devices are used:
Automatic barrier includes barrier beam 1, which rises with the help electric drive 7, cross sign 2 with glass reflectors, electric bell (buzzer) 3, 4 , mast 5 And foundation 6. The barrier beam is made of wood, 4 m long - designed to block the part of the road designated for the correct direction of traffic, and is painted in the form of stripes of white and red colors. Three signal signals are mounted on the beam reflector. At the end of the beam must be installed signal light, signaling with a red light towards the road and a white light towards the railway track.
In addition to automatic barriers, barriers are used semi-automatic, electric And mechanized (manual). Semi-automatic barriers They close automatically and are opened by the person on duty at the crossing by pressing a special button. Electric barriers are opened and closed by the person on duty at the crossing by pressing a special button. ( manual) barriers have a mechanical drive, with the help of which the worker on duty manually moves the barrier bars to the open (vertical) or closed (horizontal) position.
Crossing traffic lights and barriers are installed on the right side of the road crossing the crossing, at a distance of at least 6 m from the nearest rail. The normal position of the barriers is open, and the SPD devices are lowered. At guarded crossings, the crossing traffic light has two heads with red lights. At unguarded crossings it can be installed - two with red lights, located on the sides of the head with a moon-white light. In the absence of an approaching train, the red lights of the crossing traffic lights are extinguished, and the moon-white light flashes, indicating that there is no train approaching the railway crossing and that the signaling devices are working properly.
On the side of the vehicle entrance, road signs are installed (in accordance with traffic regulations) warning drivers about approaching the crossing.
On approaches to crossings from the railway track there are installed ( "Whistle").
On railway tracks crossing controlled crossings, they are installed at a distance of at least 15 m from the crossing. In the event of an accident or congestion at a crossing, the crossing officer on duty turns on red lights at the traffic lights. At the same time, the rail circuits of the block section on which the crossing is located are closed, as a result of which, during automatic blocking, red lights light up at the nearest traffic lights, and a white light lights up at the locomotive traffic lights of the train traveling along this block section and the driver takes measures to immediate train stop. The condition of the lamp filaments of obstruction traffic lights is monitored at the control panel of the crossing officer.
To avoid short circuiting (shunting) of the rail circuits when tracked vehicles, rollers, sleigh runners, etc. pass through the crossing, the top of the crossing is made 30...40 mm above the level of the rail heads. The width of the moving deck must be at least 6 m.
Before laying the crossing in the track of each track on the approach side of trains in the correct direction, they are installed.
On electrified sections of railways, at crossings on both sides, dimensional gates with control bar suspension height no more 4.5 m, which guarantees safe passage under the contact wire of loaded cars, cranes and other large equipment. Crossing movement of large and heavy vehicles and low-speed machines is permitted only with the permission of the head of the track and under the supervision of a road foreman or track foreman, and in electrified areas with a load height of more than 4.5 m - in the presence of a representative of the power supply distance.
To activate automatic crossing signaling devices, electric track blocking circuits or special track crossing signaling circuits are used.
Automatic activation of fencing devices occurs when the train approaches a crossing at a certain (calculated) distance. This distance is called approach section. The length of the approach section depends on the speed of trains before the crossing and the length of the roadway of the crossing and serves to provide advance notification to the crossing about the approach of a train, turn on the automatic crossing alarm and close automatic barriers (if any). The notification time depends on the time required for vehicles to clear the crossing. It includes the time required to clear the crossing, the response time of devices including fencing devices, the guarantee time reserve (this time depends on the length of the crossing, the estimated length of the road train - 24 m, the distance from the place where the vehicle stops to the crossing traffic light and on the estimated speed of movement vehicles through the crossing).
When a train enters the track circuits of the approaching section, the switch on the crossing duty officer's console turns on warning alarm, and at the crossing traffic light the red lights begin to flash alternately and the sound signal turns on; after 8…15 seconds the automatic barriers are lowered, and after some time the UZP slabs are raised. To prevent lifting of the slabs, UZPs are installed under vehicles passing over them. optical sensors. The sound signal stops after the barrier is completely lowered, and if it is absent, after the traffic light alarm is turned off. After a train passes through the crossing, the barriers are raised, the UZP plates are lowered, and the crossing traffic light turns off (a moon-white flashing light comes on).
Railroad crossings can be equipped to allow the closure of vehicle traffic through the crossing for the duration of track work, maintenance and repair work on the crossing, and in other necessary cases.
The safe movement of trains and vehicles at a guarded crossing is ensured by promptly opening and closing the barrier and giving the established signals, monitoring the condition of passing trains and lower clearance bars. If a malfunction is detected that threatens traffic safety, the crossing duty officer is obliged to take measures to stop the train, and if there is no signal indicating the tail of the train, report this to the station duty officer, and in areas with dispatch centralization - to the train dispatcher.
Karelin Denis Igorevich @ Orekhovo-Zuevsky Railway College named after V.I. Bondarenko - 2016
