DE1955949C3 - Method for hardening railway wheels - Google Patents

Description

Schicdencm pressure on the rim 3, the disc 4 and the transition to the hub 5 of the wheel I ₁ and that for different periods of time during the course of the year. Hieroei the pressure and the duration of the function of the Kulilflüssigkc'iiszuleitung Did be. Which determines ■ to be cooled Radieile.

The speed of rotation of wheels with / OU bn,

the influence of hydraulic fluid would be reduced. 1250 mm diameter should, for example, in the However, such a method has the disadvantage of hardening machine in the range from 80 to 12UU / mm ne

: o gen to have the required strength properties of all wheel parts.

The pressure ρ 1 and ρ 2 of the hardening liquid should be in the spray nozzle chambers have the following values:

It is also a method of heat treatment various elements of wheels are known, this method being a regulation of the cooling of these parts from the initial temperature with the aim the reduction of the residual stresses is provided by removing these residual stresses through plastic deformation at relevant critical points under ifl eit verri

However

to see that d'e carry out the process of plastis Deformation at only moderate temperatures can lead to the steel becoming brittle and its destruction of the wheel by tearing.

The aim of the present invention is to eliminate the mentioned night files.

The invention is based on the object of developing a method for hardening railway wheels, that ensures a uniform hardening of all radii to their full depth, without the danger significant internal tension occurs.

The object is achieved in that the hardness of liquid jets with different pressure on the entire Oberflächf λ simultaneously from rim, disk and transition to the hub of the ring is passed.

It is advantageous if the cooling liquid with 2 to 5 at pressure in the course of 120 to 200 seconds on the wheel rim and with 1 to 3 atm pressure over the course of 50 to 120 seconds on the wheel disc and the transition to the hub is guided.

The drawing shows an exemplary embodiment for carrying out the method according to the application shown.

The wheel 1 is heated to the hardening temperature and then vertically into the hardening device (not shown) used.

The vertical wheel is set in rotation at a specified speed and during its rotation is cooled by jets of hardening liquid, the pressure ρ 1 and ρ 2 being under pressure Liquid is fed in via spray nozzle devices 2 and creates a hardening zone.

During one revolution, the rim 3, the disk 4 and the transition to the hub 5 pass through of the wheel 1 completely the hardness zone.

The spray nozzle devices 2 are arranged along a radius of the wheel 1 on both sides A and B of the same and on the side C of the tread. They are divided into chambers by internal partition walls 6 in order to enable the ring 3, the disk 4 and the transition to the wheel hub 5 to cool down independently.

The number of holes provided in the spray nozzle devices 2 through the hardening liquid the pressure of the latter in each chamber, as well as the chamber dimensions along the MSharei The rim of the disc and the hub are never affected by the specified cooling speed of these Radte'le definitely.

At the same time, but at less than »5 ρ = 2 to 5 at for hardening the ring,

ρ = 1 to 3 at for hardening the disk 4 and the transition from the disk to the hub.

The periodic cooling duration should:

120 to 200 seconds for de.i Kranz and
50 to 120 seconds for the disk and the transition from the disk to the hub.

The hardening of railway wheels according to the invention Procedure ensures significantly higher strength when tested under a drop hammer and low residual stresses, an essential one

Increase in the wear resistance and impact resistance of all rim layers as well as an increase in Fatigue strength and the service life under dynamic loading and the notched impact strength of the Wheel disc.

The tensile strength of the wheel rim increases at a ^{carbon content of 0.56 0} O from 85 to 95 kp / mm ² after hardening by means of the method currently used to 105 to 110 kp'mm ² . When the carbon content is increased to 0.62 to 0.64 per cent

the corresponding strength values increase to between 112 and 115 kp / mm ² . This ensures that fine-grain austenite decomposition products are obtained in all wheel rim layers.

The fatigue strength of the wheel disc increases from 28

to 36 kp / mm ² for S'.ahl with 0.53 ⁰ O carbon content and the service life with dynamic loading from 4 · 10 ⁴ to 11 · 10 ⁴ load cycles with a simultaneous increase in notched impact strength from 2.5 to 4.0 to 5 , 5 to 6.0 kp / mm-.

so the hardening process according to the invention was largely Tried on a large number of rolled wheels made of carbon steels with 0.4 until a carbon content of 0.8% was produced. the Steels were made with manganese, silicon, chrome, van

dium and titanium in different amounts \ ind different Alloyed combinations.

It has been found that the service life of the wheels is increased by 15 ', ο and a significantly greater one Operational safety is achieved with increased speed of the trains and greater loading weight.

For this purpose I sheet drawings

Claims (2)

t2 closer to the metal volume is significantly larger. I nmlkranz more solidified. The patent claims: | £ * »* ^ Sern, however, that with rolled conditions, tii - he a) s the disc duck. 1. Process for the uniform hardening of wheels which "Knnzt" ^. ^ ^ _During ^ railroad wheels, in which the wheel is on hardness 5 st.gkei : xm ^ ^ _elasticity . heated _una Festigtemperatur, placed vertically and imDre- mebehandjung _{hQhe plastizjtät and} zähigke.t hen by means of cooling fluid jets to form ^kei £ ^rt * 5 ^'n a hardening zone is cooled, which at every Lm- ^au _{VTr 'h a} statute of limitations for hardening the iron turning of the wheel rim and disc completely PJrL _n . _be known that consists in the fact that the wheel is traversed, and with the pressure and duration, o bahnratorknown ^ ^. ^ ^ _vertical ^, the amount of coolant supplied in Abhan- aiii η * ι ^. _desse Lben by Härteflüssiggigkeit of the thickness of the cooled parts of the sets and are determined at ur ^ _{hardening liquid wia]} wheel, characterized marked keitsstram ^ _fed ührt and generates a Härzeichnet that the hardness liquid jets different here under υru _u ⁶ _{mdrehung of} the rim and with pressure on the 15 ° ^ttz ^ ^α _"ollkommen run through at the same time (see, for example entire surfaces of rim, disk and -.. ™ ^disc USSR Author's certificate No. 153287, Ov hub of the rim are passed as the uu ₃ entire surfaces of wreath, Schei USSR copyright license No. 153 287, Transition to the hub of the ring. show the uu ₃ 2. The method according to claim 1, characterized in that class ^ ^ arrangement has the proof marking big that cooling liquid with a 2 to 5 -f "hatred nf α Abkühlungsge the average pressure in the course of 120 to 200 seconds ao ^ te.l on, DAU; _{LNEN Tei} i _e by the unsuccessful the wheel rim and with 1 to 3 atm pressure in the course of "{j ^ Siche thickness of the wheel rim, the disc and from 50 to 120 seconds on the wheel disc and ^scnie ° ' ^tC "Shid it whereby significant residual Pressure for 120 to 200 seconds ^; _{LNEN Tei} i _e by the under the wheel rim and with 1 to 3 atm pressure in the course of "{j ^ Siche thickness of the wheel rim, the -disc and 50 to 120 seconds on the wheel disc and ^scnie ° ' ^tC " separates, whereby significant remainder is led to the transition to the hub, soannuneen are evoked in these. P .: also provides a process for the hardening of iron bekamt ⁱ⁵ bahnrSern, wherein the wheel on Härtetern- temperature and in a vertical position in a rotary Jen is cooled by jets of coolant and Pine variation in pressure and duration of Em-30 effect of the supplied coolant is mo ^ ichist bi jdh ^ "^^ ^ gJ 30 weg g ^ The invention relates to a method for whereby however ^ "^^ ^ g ₁ J ₁ L on S uniform hardening of E.senbahnwheels at the sigke zur Kun g _{wheel rim} and the the wheel to hardening temperature v.'hitzt perpendicular overall O ^Berf ^ ^c J ^ed _"d ^" _eri chtet and thus only a Adjusts and in turn by means of cooling fluid jets disc of the wheel gen η _{of the wheel.} cooled to form a hardened zone w, rd which: is nailed at 35 g ^^ i ^^, every revolution of the wheel rim and disc is fully rims una, _{but significant} but is passed through, and at the pressure and such a vend > _{ß & average} duration of the supplied amount of coolant Disadvantages on the then ^ e * «· - _speed, concern from the thickness of the TcIe to be cooled of the i.e.; ς« «^ ™ 1 ^£ _Γθ1ι ^g _no e sufficient ^ wheel can be determined. 4 ° Ken aog abrasion resistance It is a process for hardening E.senbahnra- strength and awwd S ^ "^ _{nuf (Jer} known in which the on hardening temperature" ^nd f ^ '™ ^ ™, _{e of the} wheel rim from its heated wheel on a horizontal Turntable on- Ob ^ ^flat ^ ^ ^a ^ of _{the cooling} hard liquid and cooling liquid gleichze.tg on the whole inner _Sch ^ _ic h "^ _{Wärmeübcrgang} surface of the rim 45 is passed sigwit ^UD ^ _wodurc h in the rim, a gro-One such method comprises the Nachte.l on ^ ¹ ^" ^ ™ 'S i _{th NSTE} falls, derzurBildunghoher that the Radkranzoberfläche only up to a.-efe ^ "peraturgra _{and that the H"} 25 w.rd solidifies to 30 mm, while practically rest ^ ^{n nNow} 8J ⁱⁿ _Nichteintr eten curing in operation, the rings up to a depth of 50 to the disc and creation of a mm will be worn. The Radjch "be" we die 5. totenJ «^ R ^ k ^ ^ ^ ^ transition sections between the disc and hub f ° ^ _n Vcstsoannungcn in the critical cross section of the well as to be between the disk and rim Ke, - high ^ pannungen ^ ^ ^ Subjected to heat hardening, which leads to the wheel, '"^ ° ⁿ wheel rim, and as a result of the fact that these parts of the wheel have low elastic, actual and rim hub of the wheel and thus strength values. 55 B not ermog- cooling with hardening a hardening of the whole oil Radvolumens in that eme Adku β resulting ambient light though, the elasticity and the Festigke.tswerte · ^ '. ^' ^^ _M ate to improve something at a second kri-wheel disc, however, there arise n-states «r ^ noen g ^. ^ ^ _transition the simultaneous immersion of all Rad te Ie SA & SSe to the hub results in stresses. E, as a wreath, a scheme and a hub in Jl in 60 from egg m . _{d ß cine very intenä} i _ve These parts have significant residual stresses, since they are cooled down at a different rate S '^ SeS to Lw. £ "'* _Hartung fiüssigkeit to form To lower the resulting upon curing chipboard ^ _n ™ 3c ™ ren have voltages at the surface of the disc, the wheels ine at high temperatures Ha ^^^ S "intensive cooling (above 500 ° C) to be started among those which can lead 65 ^ _{hzciti Nichlkühlen} the hub to riffiÄ ΪΚΑΤ * "ASA Bi f gvo ^d n ^g ^ R high stresses in the disc of the value of the ratio of cooled tunrt hei.