STEEL FOR RAILWAY CROSSING POINTS

ACIER POUR POINTS DE CROISEMENT FERROVIAIRES

English Abstract

Steel especially for production of railway and tram point crossing frogs,
including iron with weight % of 0,07 up to 0,15 % of carbon, 0,50 up to 1,20 %
of manganese, maximally 0,50 % of silicon, 1,20 up to 2,00 % of chrome, 0,40
up to 0,70 % of molybdenum, 2,50 up to 3,50 % of nickel, maximally 0,13 % of
vanadium, maximally 0,05 % of titan, maximally 0,045 % of the total contents
of aluminium in steel, maximally 0,015 % of phosphor, maximally 0,015 % of
sulphur.

French Abstract

L'invention concerne un acier destiné en particulier à la production de coeurs de points de croisement ferroviaires et pour tramway, comprenant du fer avec, exprimés en pourcentage en poids, 0,07 jusqu'à 0,15 % de carbone, 0,50 jusqu'à 1,20 % de manganèse, au maximum 0,50 % de silicium, 1,20 jusqu'à 2,00 % de chrome, 0,40 jusqu'à 0,70 % de molybdène, 2,50 jusqu'à 3,50 % de nickel, au maximum 0,13 % de vanadium, au maximum 0,05 % de titane, au maximum 0,045 % des contenus totaux d'aluminium dans l'acier, au maximum 0,015 % de phosphore, au maximum 0,015 % de soufre.

Claims

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CLAIMS
1. Steel especially for production of railway and tram point crossing
frogs is characterised by including iron with weight % of 0,07 up to
0,15% of carbon, 0,50 up to 1,20% of manganese, maximally 0,50%
of silicon, 1,20 up to 2,00% of chrome, 0,40 up to 0,70% of
molybdenum, 2,50 up to 3,50% of nickel, maximally 0,13% of
vanadium, maximally 0,05 % of titan, maximally 0,045% of the
total contents of aluminium in steel, maximally 0,015% of
phosphor, maximally 0,015% of sulphur.

Description

CA 02355868 2001-06-18
WO 01/36698
PCT/CZ00/00085
STEEL FOR RAILWAY CROSSING POINTS
Technical Field
The technical solution concerns the chemical composition of
steel on the basis of chrome - nickel - molybdenum used especially
for railway and tram point crossing frog castings.
Back round Art
The materials, which were known and used by now for
production of railway and tram point crossing frog castings are for
example materials used under trade name 13 Mn super special,
including iron with weight % of 0,60 up to 0,90% of carbon, 12,5 up
to 16,5% of manganese, maximally 0,60% of silicon, maximally 0,05%
of phosphor, maximally 0,03% of sulphur, 1,8 up to 2,2% of
molybdenum, crossing frog rail steel used under trade name UIC
900A, including iron with weight % of 0,60 up to 0,80% of carbon, 0,1
up to 0,5% of manganese, 0,80 up to 1,3% of silicon, maximally
0,04% of phosphor, maximally 0,04% of sulphur, steel used under
trade name 75~ CSD VK, including iron with weight % of 0,45 up to
0,65% of carbon, 0,75 up to 1,45% of manganese, 0,10 up to 0,50% of
silicon, maximally 0,050% of phosphor, maximally 0,050% of sulphur,
steel used under trade name 85 and 95 CSD VK, including iron with
weight % of 0,60 up to 0,80% of carbon, 0,75 up to 1,40% of
manganese, 0,10 up to 0,50% of silicon, maximally 0,04% of
phosphor, maximally 0,04% of sulphur, while the data in % represent
the maximally approved range of concentration of individual elements
or their maximal approved contents.

CA 02355868 2001-06-18
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The disadvantages of steel with the I3 Mn super special quality
include difficult machining, welding and facing of worn parts,
impossibility of fault checking by ultra-sound. The disadvantages of
the crossing frog rails in quality UIC 900A, 75 CSD VK, 85 and 95
CSD VK include low yield point, fast wearing and development of
bars, low impact value, susceptibility to fraction, low hardness and
operation life.
Disclosure of Invention
The above stated disadvantages of materials especially for
production of railway and tram point crossing frog are significantly
eliminated by steel, characterised by including iron with weight % of
0,07 up to 0,15% of carbon, 0,50 up to 1,20% of manganese,
maximally 0,50% of silicon, 1;20 up to 2,00% of chrome, 0,40 up to
0,70% of molybdenum, 2,50 up to 3,50% of nickel, maximally 0,13%
of vanadium, maximally 0,05 % of titan, maximally 0,045% of the
total contents of aluminium in steel, maximally 0,015% of phosphor,
maximally 0,015% of sulphur.
The advantages of the steel in comparison with the actual
technical situation include reaching of improved mechanical
characteristics, where the strength limit Rm is 950 MPa up to 1300
MPa, the yield limit Rp0,2 is minimally 750 MPa up to 915 MPa,
impact value KCV is minimally 20 J/cm2, hardness 290 HB up to 420
HB and ductility minimally 10%.
Descri tion
The sample of the technical solution according to the utility
model includes steel, which includes iron with weight % of 0,140% of

CA 02355868 2001-06-18
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carbon, 0,80% of manganese, 0,34% of silicon, I,76% of chrome,
0,471% of molybdenum, 2,63% of nickel, 0,087% of vanadium, 0,045
of titan, maximally 0,042% of the total contents of aluminium in
steel, maximally 0,014% of phosphor, 0,009% of sulphur.
This steel is characterised by the final strength limit (Rm) of
1147 MPa, the yield limit (Rp0,2) 91 S MPa, the impact value
(KCV+20°) 26 J/cm2, hardness 338 HB, ductility (AS) 14,8%.
Industrial Aunlicability
The technical solution can be advantageously used for railway
and tram point crossing frog castings with high requirements on
resistance against wearing. The steel is highly strenuous, it allow
good-quality welding and machining of the crossing frogs.