CN113909809A

CN113909809A - Short-process forging and rolling lining plate and preparation method of railway turnout

Info

Publication number: CN113909809A
Application number: CN202111172575.8A
Authority: CN
Inventors: 刘文利; 刘鑫; 朱明�; 席建; 杨春娥
Original assignee: Bainite Wear Pipeline Co
Current assignee: Bainite Wear Pipeline Co
Priority date: 2021-10-08
Filing date: 2021-10-08
Publication date: 2022-01-11

Abstract

The invention discloses a method for preparing a short-process forging-rolling lining plate and a railway turnout, which comprises the steps of upsetting a billet and then drawing the billet to obtain a long billet; or selecting a steel billet with a target cross section area, and drawing the steel billet to obtain a long billet; putting the long billet into a forming die, and carrying out forging forming to obtain a lining plate strip; cutting and machining the lining plate strip according to the target length of the lining plate, and normalizing and quenching to obtain a lining plate product; in the preparation method of the railway turnout, the lining plate is replaced by the railway turnout. The method reduces the longitudinal mechanical property and improves the transverse shearing capability, and has the advantages that the process flow is short, the process flow is close to a continuous rolling process, the yield of the lining plate is high, the transverse forging ratio of the lining plate is close to the longitudinal forging ratio, the transverse deformation is improved, crystal grains are refined during forming, the transverse shearing stress is conveniently improved, the fracture toughness is improved, the brittle fracture of the lining plate in the application process is reduced, the halt of a mill during operation is reduced, the lining plate is replaced, and the service time of a single lining plate is integrally improved.

Description

Short-process forging and rolling lining plate and preparation method of railway turnout

Technical Field

The invention belongs to the field of manufacturing of lining plates, and relates to a preparation method of a wear-resistant lining plate of a grinding machine.

Background

The common semi-autogenous mill, ball mill and the like have dozens of models, the diameter is 2-15 m, the length is 3-15 m, and each 20-70 lining plates are assembled into a mill cylinder. The semi-autogenous mill has different cylinder diameters and lengths, and each type of mill has lining plates with different sizes and shapes, but each type of cylinder lining plate has an installation surface and a lifting surface, and the installation surface is a circular arc surface. Usually, each lining plate has a length of 0.5-2 m, a thickness of 0.1-0.4 m, and a width of 0.2-1 m.

The lining plate is used for crushing ores, and the lining plate is required to resist high impact and scratch and abrasion. However, the higher the strength of the wear-resistant lining plate, the higher the wear resistance, the lower the toughness of the wear-resistant lining plate, and the lower the impact resistance. The physical properties of the metal material are shown by the fact that the higher the hardness the lower the toughness, which is the opposite of the requirements of the lining plate.

According to engineering requirements, the larger the diameter of the mill is, the higher the strength and the high toughness of the wear-resistant lining plate are required, and the physical properties of the wear-resistant lining plate are opposite to those of a metal material.

According to the classification of the liners, cast iron liners have high strength and poor toughness, high manganese steel liners have high toughness and low strength, and low alloy liners have insufficient toughness reserve in view of the intermediate strength between the two.

The existing lining plate is basically formed by casting, and is easy to loose and mix. The forging forming can make up for the defects in the casting forming process, but the forging upsetting and drawing process is complex, different deformation processes are adopted during forming, the mechanical properties of the longitudinal and transverse sections of the lining plate are different, and the different mechanical properties directly influence the service life of the lining plate.

The forging and upsetting process is complex, and the width of the working face of a forging machine is about 500 mm; in order to improve the yield of the lining plate and the shape forming of the lining plate, the existing forging lining plate production mainly adopts drawing out, the minimum length of the lining plate is more than 500mm, and the longitudinal performance is superior to the transverse performance; however, in the service process of the lining plate, the impact of mineral aggregate on the lining plate is mainly transverse impact, so that the existing forging lining plate is easy to break longitudinally when impacted.

2. The existing lining plate materials comprise manganese steel series, low alloy steel series and cast iron series, brittle fracture is easy to occur, and indexes corresponding to the brittle fracture cannot be used as reference acceptance criteria.

In the classification of forgings, cake-shaped and disc-shaped parts are mainly stressed transversely, and the forging process mainly takes the thickness of the cake-shaped and disc-shaped parts as the main part, so that the transverse stress performance is improved. The shaft rods are mainly stressed longitudinally, and the forging process mainly adopts drawing-out, so that the longitudinal stress performance is improved. The existing lining plate forging process does not adopt a forging method mainly comprising upsetting, firstly, the production yield is reduced, and secondly, the pressure of equipment required by lining plate forming is higher.

Disclosure of Invention

In view of the above, the present invention aims to provide a short-flow and lateral impact resistant forging method for a liner plate, wherein the liner plate is formed by integrated forging, so that the liner plate is not only resistant to lateral impact, but also can greatly reduce the cost of the liner plate.

The invention provides a preparation method of a short-process forging-rolling lining plate by long-term exploration and trial, multiple experiments and endeavors and continuous innovation, and aims to solve the technical problems, the technical scheme provided by the invention is that the preparation method comprises the steps of forging stock heat preservation treatment and lining plate quenching and tempering, a steel blank is taken, the axial direction of the steel blank is set as a Z axis, an X axis and a Y axis are positioned on the cross section of the steel blank, and the X axis, the Y axis and the Z axis form a three-dimensional coordinate system; the preparation method comprises the following steps:

step S1: upsetting a steel billet along the Z-axis direction, upsetting the upset steel billet along the Y-axis direction, and drawing to obtain a long billet with the length of 2-20 m, wherein the transverse section width of the long forging billet is +/-200 mm of the width of a lining plate; or selecting a steel blank with a target cross-sectional area, and drawing out the steel blank along the Z-axis direction to obtain a long billet with the length of 2-20 m, wherein the transverse cross-sectional width of the long forging blank is the width of the lining plate +/-200 mm;

step S2: putting the long billet obtained in the step S1 into a forming die, and carrying out forging and forming to obtain a liner plate strip; the radial deformation from the deformation of the long forging stock to the liner strip is more than 30 percent; preferably, the amount of radial deformation of the wrought blank to the backing strip is greater than 30% and less than 80%.

Step S3: cutting and machining the lining board strip obtained in the step S2 according to the target length of the lining board;

step S4: normalizing and quenching the lining plate obtained in the step S3 to obtain the lining plate with the grain size of 5-9 grade, the hardness of HRC 35-55, the tensile strength of 1000-2500 MPa, the yield strength of 900-2300 MPa and the fracture toughness of KIc 60-200 MPa m^1/2The liner plate product of (1).

According to one embodiment of the method for manufacturing the short-run forged lining plate, the steel billet is a die cast billet or a continuous cast billet.

According to an embodiment of the method for manufacturing a short-run forged lining board of the present invention, in the step S1, the feeding amount of the upset is 0.3 to 0.9 in terms of L0/H0; the cross section of the long billet is square, round or oval; the feeding and turning operation of the blank during drawing is as follows: a) spirally turning and feeding; b) carrying out reciprocating turning and feeding; or c) single sided compression.

According to an embodiment of the method for manufacturing a short-run forged lining plate, in step S1, the upper surface of the lower anvil plate of the upsetting die is a V-shaped surface, and the lower surface of the upper anvil plate of the upsetting die is an inverted V-shaped surface or a parallel or concave shape.

According to one embodiment of the method for preparing the short-process forging-rolling lining plate, when the cross section of the steel billet is square, a V-shaped cutting board is placed at one corner of the steel billet; when the cross section of the steel billet is oval, one long shaft end of the oval forging stock is placed into the V-shaped chopping block.

According to one embodiment of the method for manufacturing a short-process forged liner plate, in step S2, the forming mold includes a primary forming mold and a finish forming mold;

step S21: placing the long billet into a primary forming die, and forging and pressing to obtain a primary forming liner plate strip;

step S22: placing the pre-formed liner plate strip into a fine forming die, and forging and pressing to obtain a fine-formed liner plate strip;

the deformation is completed by one-time forging or multiple times of forging; and the precisely formed liner plate strip is used for cutting and machining to obtain a liner plate product.

According to one embodiment of the method for manufacturing a short-process forged liner plate, in step S2, the forming mold is a precision forming mold; and placing the long billet into a fine forming die, and forging and pressing to obtain a fine forming lining plate strip, wherein the length of the lining plate strip is greater than the sum of the lengths of the two lining plates.

According to one embodiment of the method for manufacturing the short-run forged lining plate, the cross-sectional shape of the lining strip comprises any one of wedge shape, triangle shape, trapezoid shape, L shape, T shape, rectangle shape and fan ring shape.

According to one embodiment of the method for manufacturing the short-process forged-rolled lining plate, in the step S2, the long billet obtained in the step S1 is placed into a forming die to be pressed and formed, after forming, the long billet is subjected to isothermal annealing and dehydrogenation in a pearlite area or is cooled to 380-room temperature and then is heated to a sorbite area, the temperature is kept for 10-100 hours, then the long billet is cooled to room temperature, and the process enters the step S3.

The invention also provides a preparation method of the railway turnout, wherein the lining plate in any one of the above embodiments is replaced by the railway turnout; the railway turnout is a type 62 turnout, a type 75 turnout, a type 92 turnout or a speed-up turnout.

Compared with the prior art, one of the technical solutions has the following advantages:

compared with the original forging process, the method is characterized in that upsetting is firstly carried out, and then drawing is carried out, in one embodiment of the method, a billet is directly and longitudinally drawn out of a long forging stock of 2-20 m repeatedly, and the long forging stock is placed into a forming die for forging and forming; in another embodiment of the invention, a long forging stock which is thickened along the Z-axis direction of a steel billet and then is upset and drawn to 2-20 m along the Y-axis direction is placed into a forming die for downward pressing and forming. The process flow is short, is close to a continuous rolling process, has high yield of the lining plate,the forging ratio of the liner plate in the transverse direction is close to that in the longitudinal direction, and the transverse shear stress is convenient to promote due to the low-temperature large-deformation grain refinement. The impact toughness is changed into the fracture toughness to be used as a main acceptance criterion for resisting fracture, and the fracture toughness index is easier to judge the actual fracture situation of the lining plate on site than the impact toughness index. When the angular ore impacts the liner, it causes the liner stresses to add and form microcracks in the plane. Because the working property of the mill belongs to high-frequency heavy-load continuous work, when the impact stress reaches the fracture toughness of the material, the crack is unstably expanded, and then the lining plate is brittle and fractured. The lining plate is set with a critical value of the fracture resistance, KIC (Mpa. m)^1/2) Or KCK (N.m)^-3/2) The crack resistance of the lining plate in the service process can be judged more easily than the impact work value. The method of the invention prevents the lining plate from being broken brittle in the application process to cause unnecessary replacement of the lining plate and stop.

The turnout is produced by adopting a process of upsetting and drawing and then extending, belongs to a conventional process, and is manufactured by using a lining plate test effect, finally forming and drawing long, pressing and forging to improve the deformation ratio of the cross section, so that the problem of transverse fracture of the turnout is solved, and the replacement performance and the safety of the turnout are improved.

In one embodiment of the invention, a large-section billet is directly and longitudinally upset and pulled to be long, a long forging stock of 2-20 m is continuously upset and pulled along the longitudinal direction, or a high stock is adopted to be thickened into a low stock according to the height-diameter ratio in the Z-axis direction, and the upset and the pull are repeated according to two mutually vertical diameter directions of the cross section of the low stock, so that the transverse mechanical property of the lining plate is improved by referring to a cake forging and rolling process. The method comprises the following steps of radially drawing a long forging stock to 2-20 m along the Y-axis direction, wherein the width of the cross section of the long forging stock is close to that of a lining plate, and a upsetting effect is formed in the forming process. The long forging stock is placed into a forming die for forming to prepare a forging rolling lining plate strip, the width dimension of the cross section of the forging stock is close to or larger than that of the lining plate, the transverse deformation rate is larger than 30 percent in the forming process, the transverse mechanical property is mainly improved, the longitudinal mechanical property is reduced in the continuous longitudinal extension and elongation process, and the transverse and longitudinal mechanical properties of the lining plate are closer to uniform. The method reduces the longitudinal mechanical property and improves the transverse shearing capability, and has the advantages that the process flow is short, the process flow is close to a continuous rolling process, the yield of the lining plate is high, the transverse forging ratio of the lining plate is close to the longitudinal forging ratio, the transverse deformation is improved, crystal grains are refined during forming, the transverse shearing stress is conveniently improved, the fracture toughness is improved, the brittle fracture of the lining plate in the application process is reduced, the halt of a mill during operation is reduced, the replacement of the lining plate is reduced, the service time of a single lining plate is integrally improved, and the operation efficiency of the lining plate is improved.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings that are required to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present invention and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained according to the drawings without inventive efforts.

FIG. 1 is a schematic view of a billet configuration according to an embodiment of the present invention.

Fig. 2 is a schematic view of a process of drawing a steel billet along the Z-axis in an embodiment of the present invention.

Fig. 3 is a schematic view of a process for drawing a steel billet along the Z-axis in another embodiment of the present invention.

FIG. 4 is a schematic view of the process of Z-axis upsetting and radial Y-axis drawing of a billet according to another embodiment of the present invention.

FIG. 5 is a schematic view of the process of Z-axis upsetting and radial Y-axis drawing of a steel billet according to still another embodiment of the present invention.

Fig. 6 is a schematic view of the spiral reverse feeding in the method of the present invention.

Fig. 7 is a schematic diagram of the multiple reverse feeding in the method of the present invention.

FIG. 8 is a schematic illustration of single-sided compression feed in the process of the present invention.

Detailed Description

The following description and the specific embodiments are made with reference to the accompanying drawings.

In order to make the objects, technical solutions and advantages of the embodiments of the present invention more apparent, the technical solutions of the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings of the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all embodiments of the present invention. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, are within the scope of the present invention. Thus, the following detailed description of the embodiments of the present invention, presented in the figures, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention.

It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it may not be further defined and explained in subsequent figures.

Example 1

The method for preparing the short-process forging-rolling lining plate described in the embodiment comprises the steps of heat preservation treatment of a forging stock and quenching and tempering of the lining plate,

specifically, the preparation method of the short-process forging-rolling lining plate comprises the following steps:

step S1: referring to fig. 1, the axial direction of a billet 100 is taken as a Z-axis, an X-axis and a Y-axis are located on the cross section of the billet, and the X-axis, the Y-axis and the Z-axis form a three-dimensional coordinate system. The X-axis and the Y-axis are two mutually perpendicular radial directions of the billet 100.

Referring to fig. 2 and 3, a billet with a target cross section area is selected, the billet is drawn out along the Z-axis direction, a square chamfer of 1m is forged by a flat anvil, then the length is changed to any length between 2 and 20m, such as 4.5m, 9m, 13m, 15m or 20m, the drawing feed amount l0/h0 is any parameter between 0.3 and 0.9, such as 0.3, 0.5, 0.6, 0.8 or 0.9, a round forging stock is made, then the upper and lower V-shaped anvils are changed to be flat into an oval primary forming lining plate, the shape is transversely oval, and the transverse cross section width dimension of the long forging stock is close to the width dimension of the lining plate.

Of course, the forging stock can also be produced by using a flat anvil to be drawn into a cuboid with any length between 2 and 20m, the drawing feeding amount l0/h0 is any parameter between 0.3 and 0.9, the forging stock with a square cross section is produced, then the opposite corners are rounded, and the width dimension of the transverse section of the long forging stock is close to the width dimension of the lining plate.

Or, referring to fig. 4 and 5, upsetting the steel billet along the Z-axis direction by using a flat anvil, and upsetting the steel billet to a height-to-diameter ratio H0/D0 which is less than or equal to 5, so as to avoid the occurrence of large drum shape, crack generation, instability and longitudinal bending at the upper and lower ends during upsetting. In fig. 4 and 5, the surfaces shown in filled form are shown as the same surface.

After the billet is thickened, the billet is subjected to cross repeated upsetting in the radial direction (X axis) and the axial direction (Z axis), the billet is drawn out and lengthened along the Y axis direction and is forged into a square chamfer with the thickness of 1mm by using a flat anvil, then the billet is replaced by an upper V-shaped anvil and a lower V-shaped anvil with the length of 2-20 m, the drawing length feeding amount l0/h0 is any parameter between 0.3-0.9, a forging stock with a circular transverse section is manufactured, then the forging stock is replaced by the upper V-shaped anvil and the lower V-shaped anvil and is flattened into an oval primary forming lining plate, the cross section is oval, and the transverse section size of the long forging stock is close to the width size of the lining plate.

Or using a flat anvil to manufacture a forging blank, drawing the forging blank into a square with the drawing length feeding amount l0/h0 being 0.3-0.9, manufacturing the square forging blank with the cross section being square, chamfering the opposite corners of the square cross section, and enabling the transverse opposite corner dimension of the long forging blank to be larger than the width dimension of the bottom of the lining board by 200 mm.

There are 3 kinds of operation methods for feeding and turning the blank when the square or round blank is drawn: firstly, the spiral type is overturned and fed, and the figure 6 is shown; secondly, reciprocating turnover feeding is often used for manual operation drawing, and the drawing is shown in figure 7; thirdly, single-side compression, namely, compressing one side along the length direction of the whole blank, and then turning over for 90 degrees to compress the other side, is commonly used for forging the large forging piece, and is shown in figure 8. In fig. 5 to 8, the direction indicated by the arrow is the billet-inverting direction.

Step S2: and (4) placing the long forging stock obtained in the step (S1) into a forming die, and carrying out forging and forming to obtain a lining plate strip, wherein the forming deformation from the long forging stock to the lining plate is more than 30%, so that the forming deformation is prevented from being small, the transverse mechanical property is prevented from being reduced, and the longitudinal mechanical property is improved.

Step S3: and cutting a plurality of lining boards with required sizes according to the required length of the lining boards by using the formed lining board strip obtained in the step S2.

Example 2

8m halfThe cylinder liner plate of the autogenous mill needs 224 blocks, the width of the liner plate is 0.5m, the height of the liner plate is 0.20m, the length of each liner plate is 1.164m, and the weight of each liner plate is 0.544 ton. A billet is cast by a die with the diameter of 800mm, and the weight is 5 tons. Drawing a die-cast steel blank with the diameter of 800mm by using a 2500-degree press, using an upper flat anvil and a lower flat anvil for rounding, carrying out spiral type overturning feeding along the Z-axis direction, wherein the drawing feeding amount L0/h0 is 0.4, drawing to a rectangular long forging blank with the cross section of 0.37m multiplied by 0.45m, then changing to an upper flat anvil and a lower L-shaped anvil, pressing downwards to form a primary forming lining plate, carrying out radial deformation rate of 35%, and then pressing downwards to form a lining plate strip by using an L-shaped lining plate fine forming die, wherein the radial deformation rate is 20%. In the present invention, the radial direction means a direction perpendicular to the longitudinal direction. Cooling to 600 ℃ after the lining plate strips are manufactured, preserving heat for 96 hours, cooling the lining plate strips to 300 ℃ in a furnace, discharging the lining plate strips, and cutting to obtain 8 lining plates with the weight of 0.544 ton, wherein the loss of the 8 lining plates is 0.648 ton, and the yield of each lining plate is 87%. After machining according to a lining board drawing, the lining board is subjected to normalizing treatment at 950 ℃ for quenching at 920 ℃ and tempering at 350 ℃. The lining plate containing the martensite structure is obtained, the grain size is 6 grade, the hardness is HRC45, the tensile strength is 1450 MPa, the yield strength is 1250 MPa, and the fracture toughness is K_Ic＞80MPa m^1/2。

Example 3

The 8m semi-autogenous mill needs 224 liner plates in the cylinder, each liner plate has the length of 1.164m, the weight of 0.751 ton, the width of 0.5m and the height of 0.35 m. A continuous casting billet with the diameter of 500mm is adopted, and the weight is 5.3 tons. Upsetting a continuous casting billet with the diameter of 500mm by using a 2500 press along the Z-axis direction by using a flat anvil, repeatedly upsetting and elongating the continuous casting billet in the one-time upsetting height-diameter ratio H0/D0 of 3 in the Y-axis direction of the cross section after upsetting, circularly elongating the continuous casting billet by using upper and lower V-shaped anvils, spirally turning and feeding the continuous casting billet along the Y-axis direction of the cross section, elongating the continuous casting billet to 0.6m in diameter by using the elongation feeding amount l0/H0 of 0.4, changing the continuous casting billet into upper and lower V-shaped anvils to be oval, and pressing down a primary forming lining plate to ensure that the radial deformation is 30%; and then a T-shaped lining plate fine forming die is adopted to press the lining plate strip downwards, and the radial deformation amount is 10 percent. After the lining plates are manufactured, the lining plates are quickly cooled to 350 ℃, the temperature is preserved for 3 hours, the temperature is raised to 620 ℃, the temperature is preserved for 48 hours, then the lining plates are cooled to 200 ℃ and taken out of the furnace, and then cutting is carried out, so that 6 lining plates with the weight of 1 ton are obtained, the loss of the 6 lining plates is 0.794 ton, and the yield of each lining plate is 85%. Press liningAfter the processing of the board drawing paper machine is finished, the lining board is quenched at 900 ℃ by normalizing, quenched at 1000 ℃ to 320 ℃, isothermally cooled, and then air-cooled to room temperature and tempered at 300 ℃. Obtaining a lining plate containing a bainite structure, the grain size of which is 8 grade, the hardness of which is HRC43, the tensile strength of which is 1300 MPa, the yield strength of which is 1150 MPa and the fracture toughness of which is K_Ic＞150MPa m^1/2。

Example 4

The 8m semi-autogenous mill needs 224 liner plates in the cylinder body, each liner plate has the length of 2.328m, the width of 0.5m, the height of 0.35m and the weight of 1.502 tons. A continuous casting billet with the diameter of 500mm is adopted, and the weight is 5.1 tons. Upsetting a continuous casting blank with the diameter of 500mm by using a 2500 press along the Z-axis direction by using a flat anvil, repeatedly upsetting and drawing the continuous casting blank into a square blank when the continuous casting blank is subjected to secondary upsetting, wherein the height-diameter ratio of the continuous casting blank is H0/D0 is 4, the cross section is subjected to repeated upsetting and drawing in the Y-axis direction after upsetting, the square blank is circularly drawn and drawn by using an upper V-shaped anvil and a lower V-shaped anvil, the square blank is fed in the axial direction of the cross section by adopting reciprocating overturning, the drawing and feeding amount l0/H0 is 0.7, the oval blank is drawn to be 0.50m of the major axis and 0.35m of the minor axis, and the oval blank is pressed downwards into a triangular liner plate strip by using a triangular liner plate fine forming die, wherein the downward pressing variable is 30%; after being made into a triangular liner plate strip, the triangular liner plate strip is quickly cooled to 150 ℃, the temperature is preserved for 1 hour, the temperature is raised to 620 ℃, the temperature is preserved for 56 hours, then the furnace is cooled to 250 ℃, the triangular liner plate is taken out of the furnace, then cutting is carried out, 3 pieces of liner plates with the weight of 1.502 tons are obtained, the loss of 3 pieces is 0.594 ton, the yield of each piece is 88 percent, after the machining is finished according to the drawing of the liner plate, the liner plate is quenched by normalizing at 880 ℃, the temperature is accelerated and cooled to the room temperature, and then the quenching treatment of high-temperature tempering at 550 ℃ is carried out immediately, so that the liner plate containing sorbite tissues is obtained, the grain size is 7 grade, the hardness is HRC38, the tensile strength is 1150 MPa, the yield strength is 900 MPa, and the fracture toughness is K_Ic＞120MPa m^1/2。

Example 5

The 8m semi-autogenous mill needs 224 liner plates in the cylinder, each liner plate has a length of 1m, a width of 0.5m and a height of 0.35m, and the weight of 0.751 ton. A continuous casting billet with the diameter of 500mm is adopted, and the weight is 6 tons. Adopting a 2500-degree press to repeatedly upset and draw a continuous casting billet with the diameter of 500mm along the Z-axis direction by adopting a flat anvil to prepare a square billet, then using an upper V-shaped anvil and a lower V-shaped anvil to prepare a round and draw the square billet, compressing the single surface along the longitudinal Z-axis direction, namely compressing one surface along the length direction of the whole billet, and then turning the square billet for 90 degrees to compress the other oneDrawing to 0.9 of round long forging stock with the diameter of 0.6m, adopting a parallel anvil to manufacture a rectangular 0.45 multiplied by 0.45m long blank, adopting a rectangular lining plate fine forming die to manufacture a lining plate strip with the radial deformation amount of 46%, quickly cooling to 350 ℃, preserving heat for 3 hours, heating to 620 ℃, preserving heat for 48 hours, furnace cooling to 250 ℃, cutting 7 lining plates with the weight of 0.751 ton, consuming 0.743 ton for 7 parts, and obtaining the yield of 88% of each part, after the lining plates are machined according to a drawing machine, quenching the lining plates at 890 ℃, quenching at 880 ℃, air cooling at room temperature, and tempering at 280 ℃ to obtain the lining plates containing the bainite/martensite structure, wherein the grain size is 6 grade, the hardness is HRC50, the tensile strength is 1800, the yield strength is 1600 MPa, and the fracture toughness is K1800_Ic＞85MPa m^1/2。

Example 6

A75-type turnout railway turnout adopts a continuous casting billet with the diameter of 500 mm. A2500-mm press is adopted to continuously cast billets with the diameter of 500 mm. Upsetting is carried out by adopting a flat anvil along the Z-axis direction, the height-diameter ratio H0/D0 is 5 when upsetting is carried out for one time, the upset anvil is used for repeatedly upsetting and growing into a rectangular billet in the Y-axis direction of the cross section after upsetting, then the parallel anvil is used for drawing out, single-side compression is carried out along the Y-axis direction of the cross section, namely one side is compressed along the length direction of the whole billet, the other side is compressed by turning over 90 degrees, the drawing-out feeding amount l0/H0 is 0.9, a 5m square forging billet is drawn out, the billet is placed into a turnout die, the billet is pressed and drawn out by pressing, the longitudinal flow direction is taken as a mark, the forged turnout is manufactured, the forged turnout is rapidly cooled to 320 ℃, the temperature is kept for 2 hours, the temperature is raised to 620 ℃, the temperature is kept for 48 hours, and then the furnace is cooled to 300 ℃ for discharging. Normalizing the turnout forging stock to 890 ℃, quenching at 920 ℃, then carrying out fog cooling to 350 ℃, carrying out isothermal treatment for 10 hours, then carrying out air cooling at room temperature, carrying out tempering at 320 ℃, then cutting a stub bar, and carrying out paper machine processing according to a turnout drawing to obtain the railway turnout comprising the bainite and martensite complex phase structure, wherein the grain size is 9 grade, the hardness is HRC45, the tensile strength is 1400 MPa, the yield strength is 1200 MPa, and the fracture toughness is K_Ic＞120MPa m^1/2。

Example 7

A75-type turnout railway turnout adopts a die casting billet with the diameter of 900 mm. Upsetting a continuous casting billet with the diameter of 900mm by using a 3150 press along the Z-axis direction by using a flat anvil, wherein the height-diameter ratio H0/D0 is 1.5 during upsetting, and after upsettingRepeatedly upsetting and drawing the cross section in the Y-axis direction in a crossing manner to prepare a rectangular billet, then using a parallel type anvil to draw the rectangular billet, spirally turning and feeding the rectangular billet along the Y-axis direction of the cross section, drawing the length by a drawing feed amount l0/h0 of 0.4, drawing the rectangular billet by a length of 8m, putting the rectangular billet into a turnout die, pressing and drawing the rectangular billet downwards, taking the longitudinal flow direction as a mark, manufacturing a forged turnout, quickly cooling the forged turnout to 200 ℃, keeping the temperature for 2 hours, heating the forged turnout to 620 ℃, keeping the temperature for 48 hours, cooling the forged turnout to 200 ℃, then discharging the forged turnout, cutting a stub, after finishing the processing according to a turnout drawing machine, quenching the turnout by normalizing at 950 ℃, fog cooling to 500 ℃, slowly cooling to room temperature, and tempering at 350 ℃, thus obtaining the turnout containing the bainite/martensite structure, the grain size grade 7, the hardness HRC48, the tensile strength, the yield strength 1300 MPa and the fracture toughness K_Ic＞100MPa m^1/2。

Example 8

A92-type railway switch is made up through such technological steps as die casting steel blank with 800mm diameter, pressing by 4500 press to obtain die casting blank with 800mm diameter, parallel forging to make it longer, repeatedly upsetting and elongating along Z-axis, reciprocating turning over, drawing to make it longer by 0.5/0 l0/h0, 8m square forging, cutting segments and material head, press shaping, cooling to 350 deg.C for 2 hr, heating to 650 deg.C for 56 hr, cooling to 300 deg.C, quenching at 860 deg.C for 820 deg.C, air cooling at 300 deg.C for 7 hr, air cooling at 280 deg.C, and machining by drawing machine to obtain the finished railway switch with bainite structure, whose grain size is 6, HRC48, tensile strength is 1500 MPa, yield strength is 1300 MPa, Fracture toughness K_Ic＞100MPa m^1/2。

Example 9

A speed-increasing railway switch is characterized in that a continuous casting billet with the diameter of 400mm is adopted, a 4500 press is adopted, a continuous casting billet with the diameter of 400mm is upset by a flat anvil along the Z-axis direction, the height-diameter ratio H0/D0 is 3.5 during upsetting, the upset-diameter continuous casting billet is repeatedly upset and pulled in the Y-axis direction of the cross section after upsetting to form a round billet, then an upper V-shaped anvil and a lower V-shaped anvil are used for round drawing, and the round billet is repeatedly upset and pulled in the longitudinal direction to form a round square billetThe blank is compressed along the axial single face of the cross section, namely one face is compressed along the length direction of the whole blank, the other face is compressed by turning 90 degrees, the drawing feed amount l0/h0 is 0.7, the round forging blank with the length of 15m is drawn out, the round forging blank is cut into sections and a stub is cut, the round forging blank is put into a press with the weight of more than 10000 tons, the press forming is carried out in a grinding tool of a finish forming turnout junction, the turnout junction is rapidly cooled to 300 ℃ after being manufactured, the temperature is kept for 1 hour, the temperature is raised to 620 ℃ and kept for 120 hours, then the furnace is cooled to 180 ℃ and taken out, the turnout junction is quenched by normalizing, air cooling at 880 ℃, slow cooling to room temperature and then firing at 300 ℃, the turnout junction drawing machine processing is finished according to a turnout drawing, the railway containing the bainite complex phase structure is obtained, the grain size is 8 grade, the hardness is HRC40, the tensile strength is 1200 MPa, the yield strength is 1100 MPa, and the fracture toughness K is K_Ic＞140MPa m^1/2。

The above is only a preferred embodiment of the present invention, and it should be noted that the above preferred embodiment should not be considered as limiting the present invention, and the protection scope of the present invention should be subject to the scope defined by the claims. It will be apparent to those skilled in the art that various modifications and adaptations can be made without departing from the spirit and scope of the invention, and these modifications and adaptations should be considered within the scope of the invention.

Claims

1. A preparation method of a short-process forging-rolling lining plate comprises the steps of forging stock heat preservation treatment and lining plate quenching and tempering, and is characterized in that a steel blank is taken, the axial direction of the steel blank is set to be a Z axis, an X axis and a Y axis are positioned on the cross section of the steel blank, and the X axis, the Y axis and the Z axis form a three-dimensional coordinate system; the preparation method comprises the following steps:

step S2: putting the long billet obtained in the step S1 into a forming die, and carrying out forging and forming to obtain a liner plate strip; the radial deformation from the deformation of the long forging stock to the liner strip is more than 30 percent;

step S4: normalizing and quenching the lining plate obtained in the step S3 to obtain the lining plate with 5-9 grade grain size, HRC 35-55 hardness, 1000-2500 MPa tensile strength, 900-2300 MPa yield strength and K fracture toughness_Ic60～200MPa m^1/2The liner plate product of (1).

2. The method for preparing a short-run forging and rolling lining plate according to claim 1, wherein the steel billet is a casting billet or a continuous casting billet.

3. The method for manufacturing a short-run wrought lining board according to claim 1, wherein in step S1, the feeding amount of the upset is L0/H0 ═ 0.3-0.9; the cross section of the long billet is square, round or oval; the feeding and turning operation of the blank during drawing is as follows: a) spirally turning and feeding; b) carrying out reciprocating turning and feeding; or c) single sided compression.

4. The method for preparing a short-run forged lining plate as claimed in claim 1, wherein in step S1, the upper surface of the lower anvil plate of the upsetting die is a V-shaped surface, and the lower surface of the upper anvil plate of the upsetting die is an inverted V-shaped surface, or a parallel or concave shape.

5. The method for preparing a short-flow forging-rolling lining plate according to claim 4, wherein when the cross section of the steel billet is square, a V-shaped cutting board is placed at one corner of the steel billet; when the cross section of the steel billet is oval, one long shaft end of the oval forging stock is placed into the V-shaped chopping block.

6. The method for preparing a short-process forging-rolling lining plate according to claim 1, wherein in the step S2, the forming mold comprises a primary forming mold and a fine forming mold;

7. The method for preparing a short-process forging-rolling lining plate according to claim 1, wherein in the step S2, the forming mold is a fine forming mold; and putting the long billet into a precision forming die, and forging and pressing to obtain a precision forming lining plate strip, wherein the length of the lining plate strip is greater than the sum of the lengths of the two lining plates.

8. The method for preparing a short-run forged liner plate according to claim 1, wherein the cross-sectional shape of said liner plate strip comprises any one of wedge, triangle, trapezoid, L-shape, T-shape, rectangle and fan ring.

9. The method for preparing the short-process forging-rolling lining plate according to claim 1, wherein in the step S2, the long billet obtained in the step S1 is placed into a forming die to be pressed and formed, after forming, the long billet is subjected to isothermal annealing and dehydrogenation in a pearlite area or is cooled to 380 ℃ to room temperature and then is heated to a sorbite area, after heat preservation is carried out for 10-100 hours, the long billet is cooled to room temperature in a furnace, and then the process is carried out in the step S3.

10. A preparation method of a railway turnout is characterized in that the lining plate of any one of claims 1-4 and 6-9 is replaced by the railway turnout; the railway turnout is a type 62 turnout, a type 75 turnout, a type 92 turnout or a speed-up turnout.