阅读说明：本技术 一种带纵向流线锻轧衬板的制备方法 (Preparation method of forging-rolling lining plate with longitudinal flow line ) 是由 刘鑫 席建 杨春娥 于 2020-06-04 设计创作，主要内容包括：本发明公开一种带纵向流线锻轧衬板的制备方法,将铸坯进行敦粗拔长,得到锻坯；将锻坯放入第一成型模具内,锻压成型得到具有纵向流纹的初成型衬板；将初成型衬板放入第二成型模具内,锻压成型得到精成型衬板；将精成型衬板根据衬板所需长度切割成型,打孔；最后淬火调质所需衬板的力学性。本发明解决了现有技术自由锻加工量大,模锻成型四角填充不满的技术缺陷。具有纵向流纹的衬板,耐高冲击不易断裂。(The invention discloses a method for preparing a forging-rolling lining plate with a longitudinal streamline, which comprises the following steps of carrying out rough drawing on a casting blank to obtain a forging blank; placing the forging stock into a first forming die, and carrying out forging and forming to obtain a primary forming lining plate with longitudinal flow lines; placing the primary forming lining plate into a second forming die, and carrying out forging forming to obtain a fine forming lining plate; cutting and molding the precisely molded lining plate according to the required length of the lining plate, and punching; finally, the mechanical property of the lining plate required by quenching and tempering is improved. The invention solves the technical defects of large free forging processing amount and unsatisfactory filling of four corners in die forging forming in the prior art. The lining plate with the longitudinal flow lines is resistant to high impact and not easy to break.)

1. A preparation method of a forging-rolling lining plate with a longitudinal streamline is characterized by comprising the following steps:

step S1: carrying out dun rough drawing on the casting blank to obtain a forged blank;

step S2: placing the forging stock obtained in the step S1 into a first forming die, and carrying out forging and forming to obtain a primary forming lining plate with longitudinal flow lines;

step S3: placing the primary forming lining plate obtained in the step S2 into a second forming die, and carrying out forging and forming to obtain a fine forming lining plate;

step S4: cutting and molding the fine molding lining plate obtained in the step S3 according to the required length of the lining plate, and punching;

finally, the mechanical property of the lining plate required by quenching and tempering is improved.

2. The method according to claim 1, wherein the step S1 specifically includes:

carrying out forging ratio or rolling ratio according to design requirements, and carrying out rough drawing on a casting blank to prepare a forging blank; the cross section of the forging stock is square or oval;

when the cross section of the forging stock is square, putting one corner of the square forging stock into a first forming die;

when the cross section of the forging stock is oval, one long axis end of the oval forging stock is placed into a first forming die.

3. The method as claimed in claim 2, wherein when the cross section of the forging stock is square, one corner of the forging stock put into the first forming die is chamfered.

4. The method as claimed in claim 2, wherein the square forging stock has a cross-sectional side length of 200 and 850 mm; the oval forging stock is obtained by forging a round forging stock, and the diameter of the round forging stock is 200-850 mm.

5. The method according to claim 2, wherein the step S2 comprises the following steps:

step S21: placing the forging stock obtained in the step S1 into a first forming die to obtain a lifting surface for forming;

step S22: molding two side edges and an installation surface to obtain a preformed liner plate with a preset width;

step S23: and slowly extending the preformed liner plate subjected to forging forming on the forging press to the discharge end, so that redundant excess materials of the liner plate gradually extend forwards and backwards to 1-20m, and obtaining the primary forming liner plate with longitudinal flow lines.

6. The method according to claim 1 or 5, wherein the step S3 comprises the following steps:

step S31: placing the primary forming lining plate into a second forming die, and longitudinally forming the primary forming lining plate into a preset thickness after the transverse die forging size is reached;

step S32: and (3) adopting a longitudinal less-feeding fast rolling mode to advance, and gradually extending the lining plate to 1-20m from front to back to obtain the precisely-formed lining plate.

7. The method of claim 1, wherein the first forming die comprises a first upper die plate and a first lower die plate; the first lower template is provided with a groove, the bottom surface of the groove is an arc surface or a plane, the width of the opening of the groove is wider than that of the bottom of the groove, and the depth of the groove is 50-500 mm.

8. The method of claim 1, wherein the second forming mold comprises a second upper die plate and a second lower die plate; one of the second upper template and the second lower template is provided with an installation surface mold surface, and the installation surface mold surface is formed by a wave arc surface, a concave-convex arc surface, an arc surface, a flat surface or a part of the whole installation surface mold surface; a lifting surface mould surface is arranged on the other template, and the mounting surface mould surface and the lifting surface mould surface enclose to form the upper surface, the lower surface, the left inclined surface and the right inclined surface of the lining plate; the left inclined plane and the right inclined plane are symmetrically arranged, and an included angle between the left inclined plane and the upper surface is 92-165 degrees; the mould surface of the lifting surface is in an arc shape, the height of the arc is 50-300mm, and the diameter is 200-800 mm; or the mould surface of the lifting surface is stepped, and the height is 50-300 mm.

9. The method according to claim 1 or 5, wherein the step S3 is not performed after the step S2 is finished to obtain the as-formed liner, and the lathe is used directly.

10. The method according to claim 1 or 8, wherein the step S2 is performed by replacing the first molding die with the second molding die, and the step S3 is not performed after replacing the first molding die with the second molding die.

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 meters, the length is 3-15 meters, 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. Typically, each liner panel has a length of 0.5-2 meters, a thickness of 0.1-0.4 meters, and a width of 0.2-1 meter.

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 molding of the lining plate is basically casting molding, and the looseness and the inclusion are easy to occur.

The forging forming includes free forging forming, die forging forming and rolling forming. Free forging and forming, and large machining amount. The die forging forming of the lining plate requires that the pressure of a forging machine is more than 3 ten thousand tons, so that the four-corner forming of the lining plate can be met. Roll forming is in the blank stage due to the complexity of thickness and shape.

The service life of the lining plate is 2-12 months, and the following technical contradictions exist;

1. the strength is improved, and the scratch wear resistance is improved, but the impact wear resistance is not improved; the fracture is easy;

2. the toughness is improved, the strength of a part is sacrificed, the technical difficulty is that the matching of the toughness is not ideal,

3. the wear-resistant lining plate belongs to a product with low added value, and is difficult to accept in the market with overhigh price.

During long-term use, the inventor finds that the technology at least has the following technical problems:

the casting wear-resistant lining plate is divided into cast iron, high manganese steel and low alloy, and has short service life. The raw material of the casting lining plate is mainly scrap steel, and is smelted in an intermediate frequency furnace, harmful elements such as sulfur, phosphorus, nitrogen, hydrogen, oxygen and the like cannot be controlled to meet the production requirement, namely the quality of the raw material is reduced, and the defects of lining plate shrinkage porosity, slag inclusion, subcutaneous air holes and the like exist in the casting forming process, which affect the performance and the service life of the casting. More than 90% of the market lining plates belong to casting molding.

The forging-type liner plate includes a free forging type liner plate and a die forging type liner plate. The defects in the casting process are overcome by adopting refined steel in the forging process, on one hand, the free forging processing amount is large, and the cost for processing the mounting surface into the arc surface is high. On the other hand, the four corners of the lining plate are not provided with radians or transition angles, the length is 1-2 meters, the thickness is 100-400 millimeters, the pressure of a forging machine required by the die forging lining plate is at least 3 ten thousand tons, and the processing amount is extremely small. The free forging forming also has the following technical problems: the feeder head accounts for 17% of the whole steel ingot, burning loss per fire is about 2%, the crop head accounts for 5-12%, and the average yield of the conventional forging is only about 60-80%. The lining plate belongs to a low-end product, and is hardly accepted by the market according to the price of a forged product. Even though the mass of the liner is relatively high, it is not ideal.

The rolling lining plate has different shapes, too thick thickness, too many types and less product demand, so the rolling lining plate cannot be produced in large batch.

Disclosure of Invention

In view of the above, an object of the present invention is to provide a lining plate with high strength and high wear resistance, which is formed by die forging and has a greatly reduced lining plate cost.

The inventor continuously reforms and innovates through long-term exploration and trial, and multiple experiments and endeavors, and in order to solve the technical problems, the invention provides a preparation method of the forged rolling lining plate with the longitudinal streamline, which comprises the following steps:

step S1: carrying out dun rough drawing on the casting blank to obtain a forged blank;

step S2: placing the forging stock obtained in the step S1 into a first forming die, and carrying out forging and forming to obtain a primary forming lining plate with longitudinal flow lines;

step S3: placing the primary forming lining plate obtained in the step S2 into a second forming die, and carrying out forging and forming to obtain a fine forming lining plate;

step S4: and cutting and forming the fine forming lining plate obtained in the step S3 according to the required length of the lining plate, punching, and finally quenching and tempering the mechanical property of the required lining plate.

Preferably, the step S1 is specifically: carrying out forging ratio or rolling ratio according to design requirements, and carrying out rough drawing on a casting blank to prepare a forging blank; the cross section of the forging stock is square or oval.

Preferably, when the cross section of the forging stock is square, one corner of the square forging stock is placed in the first forming die.

Preferably, when the cross section of the forging stock is oval, one long axis end of the oval forging stock is placed into the first forming die.

Preferably, when the cross section of the forging stock is square, one corner of the forging stock put into the first forming die is chamfered.

Preferably, the side of the cross section of the square forging stock is 200-850 mm.

Preferably, the oval forging stock is forged from a circular forging stock, and the diameter of the circular forging stock is 200-850 mm.

Preferably, the step S2 specifically includes the following steps:

step S21: placing the forging stock obtained in the step S1 into a first forming die to obtain a lifting surface for forming;

step S22: molding two side edges and an installation surface to obtain a preformed liner plate with a preset width;

step S23: and slowly extending the preformed liner plate subjected to forging forming on the forging press to the discharge end, so that redundant excess materials of the liner plate gradually extend forwards and backwards to 1-20m, and obtaining the primary forming liner plate with longitudinal flow lines.

Preferably, the step S3 specifically includes the following steps:

step S31: placing the primary forming lining plate into a second forming die, and longitudinally forming the primary forming lining plate into a preset thickness after the transverse die forging size is reached;

step S32: and (3) adopting a longitudinal less-feeding fast rolling mode to advance, and gradually extending the lining plate to 1-20m from front to back to obtain the precisely-formed lining plate.

Preferably, the first molding die includes a first upper die plate and a first lower die plate; the first lower template is provided with a groove, the bottom surface of the groove is an arc surface or a plane, the width of the opening of the groove is wider than that of the bottom of the groove, and the depth of the groove is 50-500 mm.

Preferably, the second forming mold includes a second upper template and a second lower template; and one of the second upper template and the second lower template is provided with a mounting surface die surface, and the mounting surface die surface is formed by adopting a wave arc surface, a concave-convex arc surface, an arc surface or a flat surface or is formed by using all or part of the wave arc surface, the concave-convex arc surface, the arc surface or the flat surface. A lifting surface mould surface is arranged on the other template, and the mounting surface mould surface and the lifting surface mould surface enclose to form the upper surface, the lower surface, the left inclined surface and the right inclined surface of the lining plate; the left inclined plane and the right inclined plane are symmetrically arranged, and an included angle between the left inclined plane and the upper surface is 92-165 degrees; or the mould surface of the lifting surface is in an arc shape, the height of the arc is 50-300mm, and the diameter is 200-800 mm; or the mould surface of the lifting surface is stepped, and the height is 50-300 mm.

Further, after the preliminary formed liner is obtained in step S2, the liner is machined by a lathe without performing step S3.

Further, when step S2 is executed, the first molding die is replaced with the second molding die, and after the first molding die is replaced with the second molding die, step S3 is not executed.

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

a) the invention freely forges the blank first, then forges and forms, extends the length. The applicant redesigns that free forging is firstly carried out to carry out upsetting and drawing to prepare a forging stock, the forging stock is placed into a longitudinal opening die to be forged, rolled and preformed, then the forging stock is placed into a fine forming die to be rolled and extended to form, and the bottom mounting surface and the lifting surface of the flow pattern of the forged and rolled lining plate form longitudinal forging and rolling flow patterns, so that the lining plate is resistant to high impact abrasion under the condition of high hardness, and the damage caused by fracture is reduced. The longitudinal opening is the opening of the length direction of the lining plate mould.

b) The invention can produce a plurality of forging and rolling lining plates with longitudinal metal flow lines at one time, the yield of the forging and rolling lining plates reaches more than 87.6 percent, and the finishing allowance is very little. The forged and rolled lining plate produced by the process has the advantages that the lifting surface and the mounting surface of the forged and rolled lining plate are longitudinally distributed, harmful impurities in a forged blank are eliminated or reduced by the process, and the impact resistance and the wear resistance of the lining plate are improved.

c) The die forging forming lining plate prepared by the invention has the advantages that the corners of the lining plate are full, and the defect that four corners of the die forging forming are not full of filling is overcome. The invention has lower requirement on equipment, greatly improves the yield, greatly reduces the cost under the condition of improving the product performance and improves the market competitiveness of the lining board.

d) The cross section of the forging stock is square, and one corner of the square forging stock is placed into a first forming die; or the cross section of the forging stock is oval, a long shaft end of the oval forging stock is placed into the first forming die, the vertical deformation of the forging stock is small in the die forging forming process, the material extends in the length direction of the lining plate, the lining plate is enabled to have longitudinal flow lines, the high impact resistance of the lining plate is enhanced, and the service life of the lining plate is prolonged.

e) The invention has low requirement on equipment, can be completed by using smaller forging machine pressure, and reduces the equipment cost of enterprises. The quality of the lining plate product is upgraded by a lining plate manufacturing enterprise only by modifying a die on the original forging press, so that the equipment upgrading cost is low.

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 process flow diagram of a preferred embodiment of the method for manufacturing a forged liner plate with longitudinal flow lines according to the present invention.

FIG. 2 is a schematic view of the process flow of the preparation of the primary formed lining plate in the method for preparing the forged lining plate with the longitudinal flow line.

FIG. 3 is a schematic view of the process flow of the preparation of the precision-formed lining plate in the method for preparing the forging-rolling lining plate with the longitudinal flow line.

FIG. 4 is a schematic structural diagram of free forging equipment in the manufacturing method of the forging lining plate with the longitudinal streamline.

FIG. 5 is a schematic structural diagram of a forging device for a primary formed lining plate in the manufacturing method of the forging lining plate with the longitudinal flow line.

FIG. 6 is a schematic structural diagram of a forging device for a precision-formed lining plate in the manufacturing method of the forging lining plate with the longitudinal flow line.

FIG. 7 is a schematic diagram of the longitudinal flow lines of the method for manufacturing the forged liner plate with the longitudinal flow lines of the invention.

The labels in the figure are respectively: the forging process comprises the following steps of 1 square forging stock, 2 pre-forming lining plates, 3 fine forming lining plates, 100 free forging equipment, 101 upper flat die plates, 102 lower flat die plates, 200 primary forming lining plate forging equipment, 201 first upper die plates, 202 first lower die plates and 203 grooves, 300 fine forming lining plate forging equipment, 301 second upper die plates, 311 mounting surface die surfaces, 302 second lower die plates and 312 lifting surface die surfaces.

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.

See fig. 1-7. The embodiment describes a method for preparing a forged lining plate with a longitudinal streamline, a mill wear-resistant lining plate prepared by the method, and a device for preparing the mill wear-resistant lining plate. The preparation method of the forging-rolling lining plate with the longitudinal flow line comprises the steps of selecting wear-resistant steel alloy elements, smelting/rolling/forging, heat treatment and cooling, and tempering, wherein the smelting/rolling/forging step is to smelt, roll and/or forge a casting blank into a lining plate. The wear-resistant steel alloying elements are all known alloying element formulations disclosed before the filing date of this application. And, the present embodiment is a detailed description of the processes, which are all existing processes, such as a heat treatment process and a quenching process. The invention aims to improve the strength and toughness of the lining plate by the die forging process under the condition of the same process.

Specifically, the preparation method of the forged rolling lining plate with the longitudinal streamline comprises the following steps:

step S1: and (4) carrying out dun rough drawing on the casting blank to obtain a forged blank.

The free forging equipment 100 is used, the free forging equipment 100 comprises an upper flat template 101 and a lower flat template 102, and the casting blank is roughly drawn according to the forging ratio or rolling ratio required by design to be made into a square forging blank 1 with the thickness of 300-650 mm. The length of the casting blank is more than 1 time of the length of the lining plate product prepared according to the plan.

Step S2: and (5) placing the forging stock obtained in the step (S1) into a first forming die, and carrying out forging forming to obtain a primary forming lining plate. The square forging stock 1 is forged and pressed into a primary forming lining plate by primary forming lining plate forging and pressing equipment 200. The pre-form liner forging apparatus 200 is equipped with a first forming die. There is a first molding die including a first upper die plate 201 and a first lower die plate 202, and the first lower die plate 202 is provided with a groove 203. The bottom surface of the groove 203 is an arc surface or a plane, and is specifically selected according to the actual requirement of the lining plate. The groove 203 is wider at the opening than at the bottom. The cross section of the square forging stock 1 is square, and of course, the square forging stock can also be oval. When the cross section of the forging stock is square, one corner of the square forging stock is placed into the first forming die, and the diagonal surface of the square forging stock is a vertical surface, as shown in fig. 5. When the cross section of the forging stock is oval, a long axis end of the oval forging stock is placed into a first forming die, and the surface where the long axis is located is a vertical surface. The step S2 specifically includes the following steps:

step S21: the forging stock obtained in step S1 is diagonally placed in the groove 203 of the first forming die, and the groove 203 is used for lifting surface forming or preliminary forming. The lifting surface is in the shape of an arc, the height of the arc is 50-300mm, and the diameter of the bottom arc is 200-1200 mm. The lifting surface may also be stepped, and correspondingly, the groove 203 is selected to be stepped, with a height of 50-300mm and a width of 100-500 mm.

Step S22: and forming the mounting surface and the two side edges to obtain the preformed liner plate 2 with the preset width. Typically, each finished liner has a length of 0.5-2 meters, a thickness of 0.1-0.4 meters, and a width of 0.2-1 meter. The width of the preformed liner panel 2 is therefore selected according to the actual width of the finished liner panel. The width of the preformed liner panel cannot be wider than the width of the as-formed liner panel. The width of the primary formed lining plate is not wider than that of the fine formed lining plate.

Step S23: the preforming welt after the forging and pressing shaping on the forging press slowly extends toward the discharge end, makes the unnecessary clout of welt extend to first preset length after progressively going forward, obtains to have longitudinal flow line primary forming welt. The first predetermined length is 1-20m, which is calculated based on the volume of the cast slab and the size of the slab, and is not a fixed length.

Step S3: and (5) placing the primary formed lining plate obtained in the step (S2) into a second forming die, and forging and forming by using a fine formed lining plate forging device 300 to obtain a fine formed lining plate 3. The second forming mold includes a second upper mold plate 301 and a second lower mold plate 302; one of the second upper template 301 and the second lower template 302 is provided with an installation surface mold surface, and the other template is provided with a lifting surface mold surface, wherein the installation surface mold surface and the lifting surface mold surface enclose and form the upper surface, the lower surface, the left inclined surface and the right inclined surface of the lining plate. In this embodiment, the second upper template 301 is provided with a mounting surface mold surface 311, and the second lower template 302 is provided with a lifting surface mold surface 312. The second lower platen 302 is provided with a raised face mold surface 312 for forming the fully raised face mold surface of the liner, i.e., the lower surface of the liner, see fig. 7. In this embodiment, the lifting surface die surface 312 disposed on the second lower template 302 may be a die surface suitable for a lifting surface of a corrugated liner plate, or a die surface suitable for a lifting surface of a plano-convex liner plate. The mounting surface mold surface 311 is a mold surface of the mounting surface of the lining board, and may be an arc surface, a plane, or a partial arc surface, or may be a raised line or a groove on the arc surface.

Step S31: placing the primary forming lining plate into a second forming die, and longitudinally forming the primary forming lining plate into a preset thickness after the transverse die forging size is reached;

step S32: and (3) adopting a longitudinal less-feeding fast rolling mode for propulsion, and gradually extending the lining plate to a second preset length of 1-20m from front to back to obtain the precisely-formed lining plate.

Step S4: and cutting, forming and punching the fine-formed lining plate obtained in the step S3 according to the required length of the lining plate.

Referring to fig. 7, the lifting surface of the lining plate 3 is a lower surface with a protrusion, the mounting surface of the lining plate is an arc-shaped upper surface, and the left and right surfaces of the lining plate are inclined surfaces. Generally, 20 to 70 lining plates 3 are enclosed to form a complete cylinder. In the liner plate 3 prepared in this embodiment, one corner of the square forging stock is placed in the first forming die; or one long shaft end of the oval forging stock is placed into the first forming die, the vertical deformation of the forging stock is small in the die forging forming process, and the material extends in the length direction of the lining plate, so that the lining plate has longitudinal flow lines, the high impact resistance of the lining plate is enhanced, and the service life of the lining plate is prolonged.

As a secondary option, the step S2 is omitted, the casting blank is subjected to the step S1 to obtain a forged blank, and the forged blank is directly placed in the second forming die and subjected to forging and forming to obtain the finish-formed lining plate.