Method for contact-rotaprint metered lubrication of friction surface of rail head during evacuation of rolling stock in event of jammed wheelset and use of evacuation railway shoe for this purpose

Abstract

FIELD: railway engineering.SUBSTANCE: invention relates to a method for contact-rotaprint metered lubrication of the friction surface of a rail head during the evacuation of rolling stock in the event of a jammed wheelset and the use of an evacuation railway shoe for this purpose. In order to obtain a metered supply of a third body modifying the working surfaces of dynamically loaded open friction units (DLOFU), an automatic system of contact-rotaprint supply of lubricant (ASCRSL) is used in the interaction zone of the DLOFU working surfaces in the form of a housing of contact-rotaprint lubrication systems (CRLS) connected to the housing of the evacuation railway shoe by means of a bracket, wherein the CRLS housing can rotate relative to the modified surface of the rail head. The lubricating rod shell connected to the conservative drive by a spiral spring is made of a soft metal: aluminium, babbitt, or aluminium and babbitt. The evacuation railway shoe for evacuating faulty cars with different axle load levels comprises plates with supporting working surfaces made of hard metal, as well as plates with supporting working surfaces made of soft metal. The base of the lubricant, which fills the shell, is a thermoplastic adhesive, bitumen, into which functional additives are introduced in the form of graphite, and / or thermally expanded graphite (TEG), and / or molybdenum disulphide.EFFECT: active and uneven wear of the surfaces of the rolling circles of jammed wheel pairs is eliminated, the resistance force to the movement of the shoed jammed wheelset is reduced, and the reduction in the magnitude of the traction and braking forces of the locomotives following the evacuation train is eliminated.3 cl, 7 dwg

Description

[0001] Dynamic loaded open friction units (DLFU) are widely used in technical systems; their output characteristics largely determine the reliability and efficiency of the entire system, which includes the DLFU designated above.

[0002] Thus, to increase the reliability of the wheel-rail system by reducing wheel and rail wear, a special lubricant (LM) is applied to the wheel flanges. This is achieved using specialized devices—stationary lubricators. These technical systems do not allow for precise dosing of the optimal volume. lubricant into the contact area of ​​the wheel flange with the side surface of the rail head. If the volume of lubricant is insufficient , that is The friction process transitions to boundary friction or oil starvation. Oil starvation is a critical oil level. This leads to an increase in the friction coefficient, leading to overheating of the friction surfaces, seizure, the formation of localized welds, and the ejection of material particles from one surface of the friction units and their transfer to the other. The entire system's output characteristics change dramatically, specifically, efficiency drops, and, consequently, the effectiveness of the technical system is significantly reduced. If the volume of lubricant supplied to the contact surfaces of the wheel and rail is exceeded, lubricant reaches the traction surface of the wheel tread, leading to an increase in the braking distance of the rolling stock due to a reduction in the wheel-rail adhesion coefficient by 3-5 times or more. Furthermore, exceeding the optimal volume of lubricant leads to oiling of rolling stock components and the track superstructure, including the rails, sleepers, and ballast section.

[0003] Thus, it is extremely important in a number of DNOUs to ensure the supply of an optimal volume of lubricant to the contact zone of their friction surfaces.

[0004] The prototype of the claimed invention is a method for applying a lubricant to an open friction unit [1]. The invention of the said prototype relates to mechanical engineering. The method for applying a lubricant to an open friction unit consists in that the lubricant in the form of lubricating rods is fed to the surface of the wheel flange at an angle β with a force F sufficient to ensure the process of wear of the outer shell of the lubricant and its application to the surface of the wheel flange, while where ƒ1 is the coefficient of friction of the lubricating rod along the guide that feeds the lubricating rod to the lubricated surface, P is the weight of the lubricating rod, and the ratio of the cross-sectional areas of the rod S1 in contact with the lubricated surface to the area of ​​the lubricated surface S2 is selected from the ratio As a result, complete application of the lubricant to the friction surface – the wheel flange – is ensured.

[0005] The main disadvantage of the described method is the lack of an adjustable drive for the metered lubrication of the friction surfaces (FS) of the rail head and wheel, since in this case the angle of inclination of the feed channel relative to the lubricated surface is a constant value.

[0006] Let us consider the first method for increasing the reliability and efficiency of the DNOUT by means of metered lubrication of their friction surfaces using the contact-rotaprint lubrication system (CRSL) of the DNOUT working surfaces, that is, rail ridge lubrication (LRL) of the working side surface of the rail head. At the first stage of implementing this technology, the lubricant is applied to the working surface of the wheel flange of the base rolling stock (BPS). For this purpose, technological equipment for rail ridge lubrication is used. The lubricant RAPS (TU 0254-001-01116006-2006) [2] is used as a consumable, the shells of which are made of soft metals - aluminum or babbitt, having a rectangular or round cross-section. The shell of the rods is filled with a thermoplastic adhesive, namely an environmentally friendly low-molecular product of oil cracking.As the metal shell contacts the dry, ungreased surface of the wheel flange, triboenergy is generated. This energy is proportional to the speed of movement, the contact force, and the friction coefficient of the shell material against the wheel flange material. As a result, the thermoplastic material at the friction end of the rod forms a concave meniscus, resulting in a smooth transition of a certain volume of the thermoplastic material onto the working surface of the flange. After a continuous thermoplastic coating forms as a film of a certain thickness and the resulting reduction in friction coefficient, the temperature of the rod end surface decreases to the point where the thermoplastic material transitions from a semi-liquid to a solid state. This stops the flow of thermoplastic material to the wheel flange surface.As the lubricated friction surface transitions from the lubricated flange to the side surface of the rail head, dry friction zones or localized areas of contact between the end surface of the rod and the flange surface appear. This disrupts the temperature balance of the solid state of the lubricated friction surface, increasing the temperature of the lubricated friction surface and restoring the concave meniscus of the lubricated friction surface at the end of the rod. While the optimal lubricated friction surface is formed at the end of the rod, wear of the shell occurs until the lubricated friction surface completely merges with the outer surface formed by the concave meniscus, and a flat, circular lubricated friction surface is formed at the end of the rod.

[0007] Thus, the soft metal shell (SMS) of the rod acts as a sensing element, monitoring the presence and volume of lubricant on the working surface. Furthermore, the SMS acts as a regulating element, regulating the flow of lubricant supplied to the working element of the GDS—the wheel flange of the base rolling stock—by increasing or decreasing the flow of lubricant based on the condition of the lubricant layer on the side surface of the rail head. In turn, the lubricant rod also serves as the working element for delivering the optimal volume. (mg) on ​​the side surface of the rail head (BSHR), since

[0008]

[0009] where U is the specific intensity of linear wear, mg / m 2 ,

[0010] S - area of ​​the end surface of the SS (lubricating rod), m 2Since the specific intensity of linear wear depends on 40 or more factors, including pressure, speed, ambient temperature, temperature gradient of the shell and lubricant, absolute value of temperature and its gradient, contact temperature, an equilibrium tribothermic process is formed in the contact between the end surface of the rod and the surface of the ridge, ensuring the presence of SM in the contact and its optimal volume.

[0011] Since bitumen has a transition coefficient value That

[0012]

[0013] where - the volume of CM located on the working surface of the wheel flange after its lubrication by the GRS system;

[0014] - the initial total volume supplied by the system to the wheel pair flange;

[0015] - the volume of SM remaining on the crest of the BPS after contact with the BPGR;

[0016] - the volume of SM transferred to the BPGR after contact with the lubricated comb of the base PS;

[0017] - the volume of the SM when transferred from a lubricated rail to an unlubricated ridge of the trailer rolling stock.

[0018] Below is a mathematical model of the operation of a non-driven contact-rotary lubrication system for the friction surfaces of the rail head and wheel (Fig. 1).

[0019]

[0020] The specific consumption of RAPS Q increases with the growth or increases proportionally with increasing ƒ2 and decreases with increasing ƒ1.

[0021] Feed Amount Determination Process is based on the definition of the so-called non-extrudable volume of the lubricant, which determines the specific volume of the lubricating composition that, when in contact with lubricated surfaces, does not leave the contact zone of the surfaces of open friction units, in particular, the working friction surfaces of the BPS and BPGR wheels. That is, at the same time

[0022] After the application of lubricant by the GRS system to the BPGR, the latter becomes the working element for lubricating the unlubricated wheels, and they, in turn, after contact with the lubricated rail, act as the GRS element until saturation and the formation of lubricant on the BPGR, the volume of which is equal to the non-extrudable one. This technology takes into account the probabilistic nature of the interaction of the flanges of the wheels of the BPGR with the BPGR. By creating the optimal dimensions of the contact end surface of the lubricant rod, and the optimal load on these end surfaces, and, accordingly, the specific wear rate, taking into account the actual load density of the sections and the number of working surfaces of the flanges of the wheelsets of the BPGR - n = 16 after asymptotic saturation of the operating sections of the BPGR, the thickness of the protective film R on the BPGR is ensured at the level (Fig. 2).

[0023] Fig. 2 shows a graph of the dependence of the saturation of the contact patch of the wheel with the rail - axis S, on the number of wheel pairs of the passed rolling stock with mounted equipment in the form of KRSL - axis N.

[0024] Thus, the process of regulating the metered supply of lubricant to the friction surfaces of the wheel flange-rail head friction system (WFHS) is achieved by ensuring optimal combinations of the technical characteristics of the KRSL system, in particular the magnitude and stability of the pressing force of the lubricating rod against the working surface of the flange. The specified volume of lubricant is regulated depending on variable evacuation conditions by varying the angle of the KRSL system's feed channel relative to the lubricated surface. Furthermore, to achieve metered lubrication of the WFHS "wheel flange-rail" friction surfaces and control the lubricant transfer from the surface, it is necessary to use a thermoplastic adhesive, i.e., bitumen resins, as the base of the lubricant.

[0025] In this case, in order to exclude the excess of the volume of SM supplied by surface No. 1 of the lubricating flange of the wheel to the lubricated side surface No. 2 of the rail head, and at the second stage of lubrication, when the lubricating surface No. 1 is the side surface of the rail head, and the lubricated surface No. 2 is the flange of the wheel of the rolling stock, molybdenum disulfide (MoS2) and thermally expanded graphite (TEG) are introduced into the base PS as a functional additive into the base of bitumen, while the percentage ratio by volume is 10-100% bitumen, 0-10% molybdenum disulfide, 0-50% TRG, 0-50% graphite. For the considered DNOU, the following formula is optimal: bitumen - 78%, molybdenum disulfide - 2%, TRG - 5%, graphite - 15%.This scheme ensures operation in the non-extruded volume mode, which eliminates its migration to the friction surfaces of the wheel, such as: the traction surface of the wheel in the “wheel-rail” DNOU or the surface of the rail head in the “brake shoe - traction surface of the rail head” DNOU.

[0026] The second example of the method for contact-rotary printing metered lubrication of the friction surfaces of the rail head and wheel is a railway evacuation shoe (RES), which is designed to evacuate rolling stock when a wheelset is jammed. The use of the RES shoe eliminates active and uneven wear of the rolling surfaces of jammed wheelsets, reduces the resistance to movement of the shoed, jammed wheelset, and eliminates thermal and athermal seizure, as well as the associated frictional surges. The friction surface of the rail head is modified by thermometal cladding, resulting in the formation of fractal structures of a third body on the rail head surface, possessing properties of dynamic frictional anisotropy (DFA).The implementation of the DFA phenomenon in the frictional contact between the shoe and the rail reduces the resistance to movement of the shoed wheelset under 100% sliding friction of the FP of the sole of the ERR shoe over the friction surface of the rail to a friction coefficient of 0.15-0.2. In the case of locomotive traction, this occurs under rolling friction with 1.5-2% slippage (the mode of achieving the optimal adhesion coefficient, and therefore, maximum locomotive traction). The introduction of a third body into the frictional contact between the sole of the ERR shoe and the FP of the rail head should ensure minimal wear of these surfaces.

[0027] The objective of the invention being described is that when evacuating a rolling stock in the event of a jammed wheel pair and using a railway shoe for this purpose, the phenomenon of active and uneven wear of the surfaces of the rolling circles of the jammed wheel pairs is eliminated, the resistance force to the movement of the shoed jammed wheel pair with 100% sliding friction is reduced, and there is no thermal and athermal seizure of the friction surfaces of the shoe and the rail, and the standard nominal value of the adhesion coefficient of 0.27 is ensured, i.e. the need to use sand supply to ensure the standard level of the adhesion coefficient of the locomotive wheel with the rails after the evacuation of the faulty car is eliminated.

[0028] The design diagram of the evacuation railway shoe (Fig. 3), based on the classic Bussing type shoe [3], has the following main parts: sole - 1, toe - 2, side - 3, brake shoe - 4, head - 5, bracket - 6, lubricator (KRSL) 7 and volumes of soft and hard metals - 8. In this case, the KRSL is installed at an angle of α1, or α2, or α3, depending on the axle load: minimum, average or maximum permissible, respectively (Fig. 3).

[0029] The operating diagram of the device for removing from a section a rolling stock with faults requiring the exclusion of rotation of the wheelset (Fig. 4) is the following process: a railway wheel 10 moving along a rail 9 standing on sleepers 12, an evacuation railway shoe - 15, to which a lubricator - 7 is attached on a bracket - 6, containing a lubricating rod - 14 with friction properties, the evacuation railway shoe has a rail brake 13. The diagram of the rail brake (Fig. 5) includes a cable - 16 and a lock - 17.

[0030] To improve the reliability and efficiency of the DNOU, particularly the evacuation shoe, a metered supply of lubricant is provided to the DNOU working surface, interacting with the railhead. The working surface of the sole consists of soft and hard metal volumes with friction surfaces that interact with the modified friction surfaces. An attachment, a lubricator for contact-rotograph metered lubrication of the railhead traction surface with thermoplastic antifriction lubricant, is installed at a predetermined angle relative to the horizontal surface of the railhead. To prevent displacement, the toe surface of the evacuation shoe intersects the railhead surface at an acute angle α, and the shoe is equipped with a rail brake in the form of a grip.

[0031] The implementation of this method and technological equipment of consumables due to the metered supply of SM into the contact zone ensures the environmental friendliness of evacuation operations and eliminates the reduction in the magnitude of traction and braking forces following the evacuation train of locomotives, as well as the use of technological measures to restore the specified level (at least 0.27) in the frictional connections of the wheel with the rail, as well as the wheel with the brake shoe.

[0032] The essence of the proposed method for contact-rotaprint metered lubrication of rail head and wheel friction surfaces consists of using contact-rotaprint lubrication systems (CRLS) to introduce a third body into the interface zone of dynamically loaded open friction units (DLFU). To achieve a metered supply of lubricant, an automatic contact-rotaprint lubricant supply system (ACLDS) is used in the interface zone of the DLFU working surfaces. The ACLDS has a housing connected to the unsprung or sprung masses of the rolling stock, or to the housing of the railway shoe, via elastic-dissipative links.The aforementioned third element dosedly modifies the working surfaces and increases the efficiency and reliability of the DNOU by achieving optimal friction coefficient values ​​and their stability, reducing wear on the DNOU working surfaces, i.e., the "wheel-rail" or "rail brake shoe-rail" friction systems. The KRSL housing can rotate relative to the modified surfaces of the wheel flange or rail head. The lubricating rod shell, which is connected to the conservative drive by a spiral spring via elastic-dissipative links, is made of a soft metal: aluminum, babbitt, or aluminum and babbitt. The base lubricant filling the shell is a thermoplastic adhesive—bitumen—infused with functional additives in the form of graphite and / or thermally expanded graphite (TEG) and / or molybdenum disulfide.The percentage ratio by volume of the above-mentioned components is: 10-100% - bitumen, 0-10% - molybdenum disulfide, 0-50% - TEG, 0-50% - graphite. The optimal formulation for the considered DNOU is as follows: molybdenum disulfide - 2%, graphite - 15%, bitumen - 78%, TEG - 5%. For DNOU of the "railway brake shoe - rail" type for dosed modification, that is, lubrication with solid lubricants: aluminum, babbitt or lead, the working surface of the shoe sole is made of volumes of soft metals: aluminum and (or) babbitt and (or) lead, and hard metal of steel grades 15, 3, 40. Ratio coefficient. supporting working surfaces of S1 plates made of hard metal - St.15, to supporting working surfaces of S2 plates made of soft metal - babbitt grade BN. When evacuating faulty cars with empty - low axle load at an average axle load level at maximum load level (fully loaded wagon) per axle

[0033] The rake-rail lubrication process equipment has a conservative drive connected to the loading bar and the housing via an elastic-dissipative coupling. The housing of the process equipment, in turn, is connected to the base rolling stock elements via elastic-dissipative couplings (Fig. 6), just as the loading bar is connected to the housing (Fig. 7). The elastic-dissipative coupling is introduced to improve the reliability of the process equipment and prevent component failure during high-frequency, low-amplitude fretting. This phenomenon is particularly relevant and most often encountered when installing lubrication attachments on unsprung masses, such as the axlebox assembly or shoe.

[0034] The lubricator design consists of a housing - 18, a housing axis - 19, a bar axis - 20 and a layer of elastic-dissipative material - 21 (Fig. 6).

[0035] The design of the lubricator loading device consists of a bar - 22, a cover - 23, a bar axis - 24, layers of elastic-dissipative material - 25 and a spring - 26 (Fig. 7).

[0036] The proposed method is based on the ASKRPSM - an automatic system of contact-rotary printing supply of lubricant in the DNOU, which ensures automatic monitoring of the condition of their working surfaces, the presence and quantity of friction surfaces of the lubricant in the friction zone, the temperature in the zone of their contact, as well as automatic regulation of the specified volume of the lubricant by providing a functional connection between the wear rate of the housing or shell with the lubricant in the ASKRPSM and the operating conditions of these surfaces, in particular the volume of the lubricant in the friction zone of the FP DNOU, as well as the presence of dry, boundary or liquid friction.

[0037] The technical result of the proposed invention is the ability to ensure the supply of an optimal volume of lubricant to the contact zone of the friction surfaces of the DNOU, eliminating the possibility of the friction process transitioning to the boundary friction mode or oil starvation, and, accordingly, overheating of the friction surfaces, their seizure, and the appearance of local.welding centers and tearing out of particles of material from one surface of friction units and their transfer to another surface, an increase in the reliability and efficiency of the DNOU is ensured by metered lubrication of their friction surfaces, the phenomenon of lubricant getting onto the traction surface of the wheel rolling circle is excluded, and, accordingly, a sharp increase in the braking distance of the rolling stock, which can lead to an emergency situation, and also a reduction in the intensity of wear of the friction surface of the shoe is ensured and the standard level of the adhesion coefficient is ensured when realizing the traction force of the locomotive when moving by rolling with slippage on the traction surface of the rail head.

[0038] The invention ensures metered lubricant delivery, automatic monitoring and regulation of lubricant volume in the friction zone of the DNOVT, environmentally friendly evacuation operations, and a mode for achieving optimal friction coefficient values, reducing wear on the DNOVT working surfaces. This eliminates the possibility of oil starvation and lubricant ingress onto the traction surface of the wheels, which could lead to emergency situations.

[0039] List of used literature

[0040] 1. Russian Federation Patent No. RU 2525499 C2. Method of applying lubricant to an open friction unit / V.V. Shapovalov, I.A. Maiba, P.N. Shcherbak [et al.]; B61K 3 / 02, Application No. 2011151920 / 11, declared 19.12.2011; published 20.08.2014 Bulletin No. 23.

[0041] 2. RF patent No. RU 2388635 C2. Lubricant rod / V.V. Shapovalov, I.A. Maiba, P.N. Shcherbak [etc.]; V61K 3 / 02, application No. 2008118947 / 11, application. 05 / 13 / 2008; publ. 05 / 10 / 2010 Bulletin. No. 13.

[0042] 3. Brake shoe [Electronic resource] Access mode: https: / / ru.wikipedia.org / wiki / .

Claims

1. A method for contact-rotaprint metered lubrication of the friction surface of the rail head during the evacuation of rolling stock in the event of a jammed wheelset and using an evacuation railway shoe for this purpose, characterized in that in order to obtain a metered supply of a third body modifying the working surfaces of dynamically loaded open friction units (DLFU), an automatic system for contact-rotaprint supply of lubricant (ASCRPSM) is used in the interaction zone of the DLFU working surfaces in the form of a housing of contact-rotaprint lubrication systems (KRSL), connected to the housing of the evacuation railway shoe by means of a bracket, wherein the KRSL housing has the ability to rotate relative to the modified surface of the rail head, and the shell of the lubricant rod, connected to the conservative drive by a spiral spring, is made of a soft metal: aluminum, babbitt or aluminum and babbitt,wherein the evacuation railway shoe for evacuating faulty cars with different axle load levels contains plates with supporting working surfaces made of hard metal, as well as plates with supporting working surfaces made of soft metal, wherein the ratio coefficient K, п=S1 / S2of the supporting working surfaces S1 of the plates made of hard metal and the supporting working surfaces S2 of the plates made of soft metal for the evacuation of faulty empty cars is equal to two, for the evacuation of faulty cars of average loading level is equal to 2.5, for the evacuation of faulty fully loaded cars is 10 / 3, and the basic base of the lubricant, which fills the shell, is a thermoplastic adhesive - bitumen, into which functional additives are introduced in the form of graphite, and / or thermally expanded graphite (TEG), and / or molybdenum disulfide, while the percentage ratio by volume is 10-100% bitumen, 0-10% molybdenum disulfide, 0-50% TEG, 0-50% graphite.

2. The method according to paragraph 1, characterized in that the optimal formulation for the lubricant that fills the shell is the following: molybdenum disulfide 2%, graphite 15%, bitumen 78%, TEG 5%.

3. The method according to paragraph 1, characterized in that the working surface of the sole of the shoe is made from volumes of soft metals - aluminum, and / or babbitt, and / or lead, and hard metals - steel grades 15, 3, 40.

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