CN218591773U - Split hole type chilling block - Google Patents

Abstract

The utility model relates to a split type pass chiller, including the pass chiller that 8 at least fan-shaped chills make up, it sets up in the roll-in mould through the form of expanding tightly to guarantee its stable connection. The utility model discloses a pass chill structure of the fan-shaped chill combination of polylith adopts the tight form that expands to set up in the roller die inboard to the effectual deformation problem of having solved the pass chill makes things convenient for the drawing of patterns, can effectually realize that the industrialization production centrifugation has the type casting roll.

Description

Split hole type chilling block

Technical Field

The utility model relates to a roll field of making especially relates to split type pass chill.

Background

Since hot rolled steel begins to exist, rollers are always the main working parts and tools for continuously and plastically deforming metal on a rolling mill, and the importance of various physical and mechanical properties of the rollers is obvious because the performance of the rollers directly influences the production efficiency of the rolled steel and the surface quality of steel. The roll production industry is actively introduced into the advanced technology of the related industry for many years, and the roll production industry has great progress and development in the aspects of production process, material performance and the like, thereby greatly promoting and promoting the development of the steel rolling industry. For example, new material and new process rollers with excellent performance such as a centrifugal casting high-speed steel roller and a CPC high-speed steel roller are put forward in the aspect of rolling plate strip steel. Rolls with excellent wear resistance, such as centrifugal high-speed steel rolls and tungsten carbide rolls, used for finish rolling stands are introduced in the on-line bar rolling industry. The rollers produced by the new materials and the new process show good rolling performance after being put on the market, and simultaneously promote the development of the steel rolling industry of plate strip steel and bar steel.

However, the rolls for rolling the section steel have not been developed for a long time, most of the rolls used for rolling the section steel are conventional rolls with relatively poor wear resistance and toughness, and centrifugal rolls have been introduced in the rolling of a small part of the section steel in recent years, but the materials are limited to medium NiCrMo infinitely chilled ductile iron rolls, pearlite ductile iron rolls, bainite ductile iron rolls with a very small number, and the like. Although the rolling reduction is improved in the unit rolling amount, the improvement is not large. If the roller with higher material and higher hardness is introduced again, the deep hole machining difficulty is greatly increased, and huge drilling cost and machining efficiency loss are inevitably consumed. And also suffers from a decrease in wear resistance due to a decrease in hardness after the deep hole is opened.

The product of the utility model is a roller for hot rolling production of large, medium and small section steels; rough and medium rolling rollers of bar and wire rolling mills. These rolls have a common feature, namely: deep pass is required (the depth of the hole is 40-150 mm, except for the individual flat roll rolling of the wire and bar materials in rough and medium rolling). The basic structure of these rolls as shown in fig. 1 comprises: a transmission end roll neck 1, a transmission end flat head 2, an operation side roll neck 5, a roll collar 4 of a roll body part, a groove 3 of the roll body part and the like.

The traditional roller production process is that the roller body is cast into a smooth roller, the roller body is delivered in a smooth state after being processed according to an order drawing (a flat roller drawing), then a steel rolling manufacturer performs slotting according to a hole pattern drawing, such as the processing of a rolling groove 3 in a figure 1, and finally the roller is operated and rolled. This method has been used for many years (since the rolling of sections and wire and bars, it has been used) and has been found to have a number of disadvantages in long-term rolling practice, most notably the fact that the rolls tend to be grooved deeper (the deeper the larger the section), typically 40-150 mm or even deeper. Thus, the hardness fall of the upper part and the lower part of the rolling groove is greatly increased, the wear resistance of the rolling groove is greatly reduced, and obviously, the service life of the roller is shortened. The problems finally caused are frequent groove replacement and roll replacement, the operation rate of the rolling mill is greatly reduced, and the rolling cost is improved.

Because the roll body of the roll is cast by coating refractory material on the inner surface of a cold die (which is conventionally called as a roll die), the supercooling degree of molten iron closest to the cold die is relatively large during casting, so that the structure crystal grains on the outer layer surface of the roll are very fine and have relatively high hardness, but the supercooling degree is smaller and smaller along with the extension towards the inner layer direction of the roll, and the structure crystal grains are relatively larger and larger. This is the inevitable consequence of the solidification of the liquid metal, that is to say the difference in structure from the outside to the inside is unavoidable regardless of the material of which the rolls are cast. Differences in the texture also necessarily produce variations in stiffness. That is, the difference in hardness from outside to inside of different materials is different, but the difference in hardness is inevitable. Then, the steel section roll is produced by a common flat roll casting method, the internal structure of a rolling groove becomes thick and the hardness is gradually reduced along with the downward extension of the rolling groove after the roll body of the roll is grooved, and the hardness of the groove bottom is reduced to a relative minimum value after the groove is grooved, so that a large hardness difference is formed between the upper surface of the rolling groove and the groove bottom, which is called as hardness drop. Similarly, the hardness of the upper part of a rolling groove is high, the wear resistance is good, the hardness of the bottom of the rolling groove is low, the wear resistance is poor, the bottom of the rolling groove with poor wear resistance is firstly worn to generate hole type deformation when steel is rolled, although the wear resistance of the upper part of the rolling groove is better, the lower part in the same rolling groove is deformed to be forced to replace the rolling groove, and the service life of the rolling groove is finished. Therefore, the hardness difference between the upper part and the lower part of the rolling groove can seriously affect the use effect and the service life of the roller due to the characteristic of deep groove opening of the section steel roller.

The processing amount of the rolling groove required by the drawing is very large, and the weight loss of the opening is calculated to be about 20-40% of the weight of the flat roll. Therefore, the deep grooving of the roller consumes a great deal of working hours, and the consumption of turning tools is greatly increased. If the number of the grooved rollers is large, a plurality of numerical control processing machines are required to be added. Therefore, the grooving processing cost is very huge, the processing period is prolonged, and the capital occupation is increased.

When the roll surface of the roll is grooved, because the machining allowance is large, long-time hole opening and turning are needed, in addition, the hardness of the outer layer of the roll is relatively hard, if bainite ductile iron or high-speed steel is harder, the hardness of the material with the higher hardness is higher, the groove of the material with the higher hardness is bound to bear high-strength extrusion for a long time in the long-time machining process, a large amount of turning heat is generated under the action of the high-strength extrusion, the turned scrap iron is red when the iron is turned, the temperature of the scrap iron is up to 700-800 ℃, and the temperature of the roll at the turning position is also up to 500-600 ℃. If the roll is subjected to the dual actions of high-strength extrusion and high temperature for a long time, on one hand, the matrix structure is transformed, particularly, austenite with a certain proportion is mostly remained in the matrix structure of a high-hardness material such as bainite ductile iron or high-speed steel, the austenite is subjected to the structure transformation under the action of high temperature, the volume is expanded when the structure is transformed, if the volume is expanded, the stress of the outer layer of the roll is increased rapidly under the influence of high-strength extrusion acting force, if the stress exceeds the limit which the toughness of the material can bear, the stress is released, and the concrete expression is that the machined rolling groove is cracked suddenly. Even if the stress at that time does not exceed the material bearing limit, a great potential stress hazard is formed during processing, great threat is brought to the next step of rolling on the roller, and the roller is likely to release stress suddenly under the action of rolling temperature rise and rolling load during passing steel, so that the roller is cracked or cracked directly.

There are also methods for realizing an integral centrifugal casting of a profiled roll, for example, chinese utility model patent with publication number CN100404172C discloses a production method of a centrifugal casting grooved composite roll, which comprises arranging a plurality of metal rings in a metal mold, cutting the metal rings into two semicircles by wire cutting, and fixing the metal rings in the metal mold by bolts after holes are formed in the metal mold for casting; however, in practice, if the method is used for casting, after casting is completed, the chill is found to be deformed after cooling and unpacking, the deformed chill can not be used any more and can only be used after being repaired by a lathe, but turning and repairing are troublesome after each use, more importantly, the size of the repaired chill is changed, the assembly of the chill and the matching of the inner hole of the roller die are seriously influenced, the machining allowance of the chill part is also influenced, and if the machining allowance is too large, the chilling effect of the hole pattern is lost, so that the service performance of the rolling groove is reduced. Meanwhile, the connection of the thread structure is not favorable for unpacking, the roller die can experience cold and hot changes in the centrifugal casting process, the temperature difference is large, the angle of the threaded connection position can be changed simultaneously when the roller die rotates at a high speed and is centrifugal, the difficulty of unpacking can be increased rapidly under the influence of expansion with heat and contraction with cold, the roundness of a metal mold can be influenced due to difficulty in unpacking, and the deformation of the metal mold box body can be caused in the unpacking process and the preparation process, so that the scheme can not meet the industrial production when trial-manufacture is found, and numerous technical problems need to be solved. Therefore, a hole-type chill which can effectively solve the deformation of the hole-type chill and can effectively realize demoulding is urgently needed.

SUMMERY OF THE UTILITY MODEL

Technical problem to be solved

In order to solve the above problem of the prior art, the utility model provides a split type pass chill has realized the centrifugal casting of profiled roll and the effectual deformation problem of solving the pass chill, can the adaptation mass production, effectual reduction production and processing cost to very big increase the life of profiled hole chill.

(II) technical scheme

In order to achieve the above object, the utility model discloses a main technical scheme include:

split type pass chiller, its characterized in that: the hole-shaped chilling block is formed by combining at least 8 fan-shaped chilling blocks and then expanding the combination to be arranged in an annular structure of a metal inner wall so as to limit the deformation of the fan-shaped chilling blocks; the hole-type chiller is provided with at least one expansion groove for expanding the fan-shaped chiller; and an expansion pin is arranged in the expansion groove.

Further, the metal mold is a roller mold or a roller mold internal mold arranged in the roller mold and used for changing the inner diameter of the roller mold.

Further, the hole-type chiller is cut into 12 fan-shaped chills by a metal ring wire.

Furthermore, the plane end of the fan-shaped chiller is provided with a positioning hole for positioning the adjacent fan-shaped chiller.

Furthermore, the positioning hole is arranged close to the outer circular arc of the fan-shaped chilling block;

furthermore, the distance between the positioning hole and the outer circular arc of the fan-shaped chilling block is 25-35mm.

Further, an expansion groove for expanding the hole type chilling block is arranged between at least two adjacent fan-shaped chilling blocks.

Further, the expansion slot is wedge-shaped; the expansion pin is a wedge pin.

Furthermore, a groove for reinforcing refractory paint is arranged on the inner side of the fan-shaped chilling block.

Furthermore, the cross section of the groove is in an inverted triangle shape, and the bottom angle of the groove is in an arc shape.

(III) advantageous effects

The utility model has the advantages that: the deformation problem of the hole type chilling block is effectively solved through the matching positioning of the hole type chilling block with the split structure and the expansion structure, the hole type chilling block can be stably used for a long time, demoulding production is convenient, and the service life and the mechanical property of the roller are effectively prolonged through the improvement and optimization of the preparation method.

Drawings

In order to more clearly illustrate the technical solution of the embodiments of the present invention, the drawings which 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 that for those skilled in the art, other related drawings can be obtained according to these drawings without inventive efforts.

FIG. 1 is a schematic view of a profiled roll construction;

FIG. 2 is an exploded view of the upper roll body molding machine of the present invention;

FIG. 3 is an exploded view of the molding apparatus of the lower roll body according to the present invention;

FIG. 4 is a sectional view of the upper roll integral cavity assembly structure of the present invention;

FIG. 5 is a sectional view of the whole lower roller cavity assembly structure of the present invention;

FIG. 6 is a sectional view of the solid structure after the upper roll casting solidification of the utility model;

FIG. 7 is a cross-sectional view of the solid structure of the lower roll after the lower roll is poured and solidified;

FIG. 8 is a sectional view of a hole type chill according to the present invention;

FIG. 9 isbase:Sub>A sectional view ofbase:Sub>A hole type chill A-A according to the present invention;

FIG. 10 is an enlarged view of the first hole type chill of the present invention;

FIG. 11 is an enlarged view of the second part of the hole-type chiller of the present invention;

description of the reference numerals

1. A transmission end roll neck 2, a transmission end flat head 3, a groove 4, a roll collar 5 and an operation side roll neck;

10. a roller die 101, a roller die runway 102 and end cover pin holes; 20. a hole type cold iron, 201, an expansion groove, 202 and an expansion pin; 21. fan-shaped chilling blocks 211, positioning holes 212, positioning pins 213, grooves 30, end covers 301, end cover expansion pins 302 and end cover sand molds;

103, rolling the inner die of the die; 40. a bottom box 401, a bottom box sand mold; 50. a riser box 501, and a riser box sand mold;

60. an upper roll blank 601, an upper roll core upper roll neck 602, an upper roll core lower roll neck 603, an upper roll outer layer 604, an upper roll intermediate layer 605, an upper roll core body;

70. a lower roller blank 701, an upper roller neck of a lower roller core part 702, a lower roller neck of a lower roller core part 703, an outer layer of a lower roller 704, a middle layer of a lower roller 705 and a roller body of the lower roller core part;

Detailed Description

To make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the drawings of the embodiments of the present invention are combined to clearly and completely describe the technical solutions of the embodiments of the present invention, and obviously, the described embodiments are some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative work belong to the protection scope of the present invention. Thus, the following detailed description of the embodiments of the present invention, presented in the accompanying drawings, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative work belong to the protection scope of the present invention.

In the description of the present invention, it should be noted that the terms "upper", "lower", "inner", "outer", "front end", "rear end", "both ends", "one end", "the other end" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplification of description, but do not indicate or imply that the device or element to which the reference is made must have a specific orientation, be constructed in a specific orientation, and be operated, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In the description of the present invention, it is to be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "provided," "connected," and the like are to be construed broadly, and for example, "connected" may be either fixedly connected or detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present invention can be understood in specific cases to those skilled in the art.

In the first embodiment, please refer to fig. 1-11:

the split type hole-shaped chill comprises a plurality of hole-shaped chills 20 which are arranged in parallel along the axial direction in a roller die 10 and are used for modeling a rolling groove 3; the hole-shaped chilling block 20 is formed by combining at least 8 fan-shaped chilling blocks 21 and then expanding and tightly arranging an annular structure on the inner wall of the roller die 10 so as to limit the deformation of the fan-shaped chilling blocks 21. The hole-shaped chilling block 20 is used for being arranged in the roller die 10 to form the rolling groove 3, so that demoulding is convenient, and meanwhile, close surface contact with the inner wall of the roller die 10 is needed to be carried out to avoid generating gaps, the aim is to prevent molten iron from entering the gaps to influence the product quality during centrifugal casting, when the centrifugal casting is carried out, the roller die 10 shown in figure 1 is horizontally placed, a roller die runway 101 is in contact with a side supporting wheel on a centrifugal machine, the roller die 10 is driven to rotate at a high speed through the rotation of the side supporting wheel of the centrifugal machine, if the gaps exist, the molten iron rotating at a high speed can enter the gaps to be adhered to the inner wall of the roller die 10 after cooling and solidification, the roller die 10 is easily damaged due to influence on demoulding, therefore, the hole-shaped chilling block 20 cannot be fixed by adopting a mode of damaging the whole structure of the roller die 10, for example, a threaded hole is used for fixing, and the special process requirements of centrifugal casting, the uniformity of quality distribution also needs to be ensured during high-speed rotation, so that the roller die 10 can stably rotate, and the difficulty in fixing the hole-shaped chilling block 20 is increased. The utility model discloses a carry out the tight setting of expanding after cutting into at least 8 little fan-shaped chills 21 with pass chiller 20 in roller mould 10 inner walls, can realize with the inseparable laminating of roller mould 10 inner walls, do not destroy the whole uniformity of roller mould 10 simultaneously, also do not increase gaseous fixed part and increase weight, guarantee that the distribution of whole quality is even to the effectual shaping that has realized the shaped roller. The purpose of cutting into at least more than 8 fan-shaped chills 21 simultaneously can also be through the effectual deformation that takes place of the mode that sets up that expands when centrifugal casting, because at the centrifugal casting, fan-shaped chills 21 can take place to expand and contract when being heated and cooling, and the repetition of this process will cause the deformation of fan-shaped chills 21, and this deformation is not allowed, will influence the final quality after the roll shaping on the one hand, will cause pass chiller 21 to become disposable consumables on the other hand. In order to ensure that the hole-type chiller 20 can realize the demolding effect, cutting the hole-type chiller into two or three blocks is a common means in the prior art, but the method can only realize demolding, but the prior art does not consider more serious technical problems such as chiller deformation and the like, and cannot actually solve practical problems such as casting, cost control and the like, which is also a reason why the mass production of related technologies is not realized in the prior art. The utility model discloses a reduce fan-shaped chill 21's big or small back, can effectual reduction fan-shaped chill 21's deflection, in order to satisfy the demand of industrial production, because the pitch arc length that fan-shaped chill 21 occupied in circular shortens, under same intensity, it can realize littleer deformation, combine simultaneously the utility model discloses special bloated tight structure, provided sufficient holding power, can guarantee that fan-shaped chill 21 expands in the earlier stage that centrifugal casting molten iron got into and extrudees each other, further avoid producing the gap, under the restriction of roller die 10, keep original annular structure, simultaneously at the cooling shrinkage in-process, the holding power that provides when bloated tightly on the one hand can reduce fan-shaped chill 21's deformation, on the other hand because fan-shaped chill 21 has less length, the contact surface of two adjacent fan-shaped chills 21 also can provide frictional force and prevent its deformation, and become the wedge between fan-shaped chill 21's the contact surface, can further fan-shaped chill 21 prevents its deformation, thereby fundamentally has solved the problem of deformation.

In an embodiment of the present invention, the hole-type chiller 20 is formed by cutting a metal ring into 12 fan-shaped chills 21. The plane end of the fan-shaped chiller 21 is provided with a positioning hole 211 for positioning the adjacent fan-shaped chiller 21; a positioning pin 212 is arranged in the positioning hole 211; the positioning hole 211 is arranged close to the outer circular arc of the fan-shaped chiller 21; the distance between the positioning hole 211 and the outer circular arc of the fan-shaped chiller 21 is 25-35mm. An expansion groove 201 for expanding the hole type chilling block 20 is arranged between at least two adjacent fan-shaped chilling blocks 21; an expansion pin 202 is arranged in the expansion groove 201. The fan-shaped chills 21 are arranged into 12 blocks, the fan-shaped chills 21 are hardly deformed and can be repeatedly used for a long time, the positioning problem of the fan-shaped chills 21 is solved by the positioning pins 212, the positioning pins 212 not only can be conveniently positioned, but also can effectively prevent the inward shrinkage at two ends of the fan-shaped chills 21 when being cooled and deformed, meanwhile, the positioning pins 212 are arranged at positions far away from the center, and are close to the position of an outer arc as much as possible while ensuring enough supporting force, and by the design mode, the positioning pins 212 are far away from high-temperature iron (steel) water, are heated and relieved, and the temperature rise time is prolonged, so that the positioning pins 212 can fully play a role in limiting the deformation of the chills; during the cooling, the locating pin 212 that is located the outside cools off earlier, because it is straight, can guarantee straight characteristic equally after current cooling, and fan-shaped chill 21 will take place to contract the deformation gradually towards the inlayer when refrigerated, and at this moment cooled locating pin 212 in advance just can not receive fan-shaped chill 21 to contract the deformation in the influence that deforms and then warp together in advance, but can restrict fan-shaped chill 21 to further reduction fan-shaped chill 21's deformation. The inward shrinkage deformation refers to the deformation formed by inward shrinkage of two ends of the fan-shaped chiller towards the direction of the center of an arc due to the arc structure of the fan-shaped chiller and the cooling from outside to inside, the deformation can cause the shape change of a rolling groove of a roller, the problem of difficult repair is caused, and the deformed chiller is difficult to be repeatedly used.

In an embodiment of the present invention, a groove 213 for reinforcing refractory coating is formed inside the fan-shaped chiller 21; the cross section of the groove 213 is an inverted triangle, and the bottom angle is arc-shaped. Can make things convenient for the connection stability of hanging the brush and promoting the coating of coating through slot 213, avoid the separation problem of coating when centrifugal casting.

In an embodiment of the present invention, a roller mold inner mold 103 for changing an inner diameter of the roller mold 10 is disposed in the roller mold 10; a plurality of hole type chilling blocks 20 used for modeling the rolling groove 3 are arranged in the roller die inner die 103 in parallel along the axial direction. The same roller die 10 can be used for casting the upper roller and the lower roller through the roller die inner film 103, and the number of dies is saved.

The analysis shows that the main reason for deforming the hole-type chilling block 20 is as follows: the hole type chilling block 20 combination is characterized in that after the outer layer iron (steel) of the roller is poured by molten iron, the hole type chilling block is completely wrapped by high-temperature metal liquid, the chilling block is suddenly and rapidly heated, the temperature rises to about 900-1000 ℃, the temperature lasts for about 30 minutes under the action of high temperature, and then the temperature begins to slowly fall. The hole-shaped chilling block expands during high temperature, so that the hole-shaped chilling block tightly expands on the inner surface of a roller die, the temperature of the pouring body slowly decreases along with the continuous absorption of the heat of metal liquid by the hole-shaped chilling block and the roller die after the pouring is finished, and the temperature of the roller die continuously diffuses into the air, the temperature of the whole pouring body slowly decreases, the volumes of the metal liquid in the roller die and the hole-shaped chilling block gradually shrink in the continuous decreasing process, the hole-shaped chilling block formed by combining two single blocks has no shrinkage resistance due to the butt joint opening end when the volumes shrink, the outer side of the chilling block arc structure shrinks after radiating heat, the temperature of the inner side cools slowly, and is still in a high-temperature state, when the outer side shrinks and deforms inwards, the inner side is easier to deform along with the outer side due to high temperature, and the radian of the single block is long in the prior art in order to realize the fixing of positioning, so that the integral shrinkage is relatively large, and a final result is formed: the shrinkage deformation of the hole-shaped chilling block is large. The monolithic deformation of the hole-type chilling block can not form a complete round hole after combination, and if the hole type is restored to be round by adopting a machining restoration method, other serious problems exist: (1) The hole-type chill assembly cannot be firmly combined without a roll die, and cannot be integrally repaired on a lathe, but the repair of a single block is almost impossible. (2) Some dimensional deviation of the hole-type chilling block after the first repair is added is still barely acceptable, but the problem is that deformation is carried out every time, the hole-type chilling block needs to be repaired once after deformation, and large dimensional deviation can be generated during the second repair, so that the assembly of the hole-type chilling block and the chilling effect of a rolling groove are seriously influenced, and the deformation repair after the second repair is not to be said. Therefore, this is a fatal problem that seriously affects the process, which must be solved completely, otherwise, the process is essentially a process concept or concept, which cannot be realized at all!

Through the problems found in the trial production, after careful analysis and research, the hole-shaped chilling block is continuously decomposed into a plurality of blocks, and the deformation of a single block of chilling block is reduced by reducing the radian of each chilling block so as to control or basically eliminate the deformation of the whole hole-shaped chilling block assembly. In the trial production period, 4 blocks, 6 blocks, 8 blocks and other ways are tried in sequence to solve the deformation problem of the hole type chill, but all the ways fail to achieve the purpose that the whole deformation amount of the hole type chill assembly cannot meet the production requirement. And along with the increase of chilling block quantity, the location of chilling block and the installation degree of difficulty sharply increase, along with the increase of quantity, its installation in roller mould 10 is also more difficult with the location, and how to guarantee that the chilling block can be stable and accurate location installs also a difficulty in the roll inside. In the original scheme, transversely put the roll when decomposing into installation behind the several chills, then put into a circular in proper order, utilize the little clearance of chill self and extrude each other and realize the location, and during the rotation, the chill also can closely laminate with the roll inner wall because of centrifugal force, but along with the quantity increase that falls into the chill, this mode location just has been difficult to realize, and the clearance is difficult to control. The utility model discloses thereby it makes the inseparabler that can laminate between the fan-shaped chill 21 to expand tight round pin 202 extrusion in, and the mounting means also changes into simultaneously and installs pass chill 20 with the vertical placing of roller die 10, increases locating pin 212 simultaneously and fixes a position and consolidate, the effectual difficult problem of installation of having solved.

The hole-shaped chilling block 20 is made of heat-resistant metal materials, so that the chilling block is prevented from deforming for a long time. And then, continuing to perform trial production verification, and completely achieving the expected effect by adopting a mode of 12-block combination, namely achieving the purpose that the hole type chilling block combination is basically not deformed.

In the production practice, the design method of the hole-type chilling block adopting the 12-block assembly is found to solve the problem of shrinkage deformation of the hole-type chilling block, but a new problem is generated along with the shrinkage deformation of the hole-type chilling block, namely the assembly difficulty is greatly increased after the number of the chilling blocks is increased to 12. Therefore, the problems of assembly, embedding and fixing are solved.

The difficulty of assembling the design of 2 or 4 blocks is very small, but the difficulty of assembling 12 blocks is greatly increased. Therefore, after a plurality of attempts and careful researches, positioning holes are designed on the connecting end surfaces of the single-block hole type chillers, and positioning pins are arranged in the positioning holes, so that the adjacent single-block hole type chillers can be connected together, and the single-block hole type chillers are prevented from falling off when being suspended in the air in the installation process. And hoisting the hole type chiller which is combined in advance into the hole in the roller die by using a special hoisting tool of the specially manufactured hole type chiller assembly, and tightly pinning the expansion pin at the positioned position to finish the installation of the hole type chiller.

Repeated trial production for many times proves that the deformation problem of the hole-type chilling block can be effectively solved by adopting the design of the hole-type chilling block with the 12-block combination, and after failure and improvement for many times, a positioning pin hole is designed between single-block hole-type chilling blocks finally, the single-block chilling blocks are connected by adopting a positioning pin during assembly, after all the single-block hole-type chilling blocks are combined in the circumferential direction, an expansion groove 201 with 3 percent of wedge degree is designed between the last two chilling blocks (no positioning pin is arranged between the two chilling blocks), and the 3 percent of wedge degree is driven into the expansion groove 201 for expansion, so that the assembly of the 12-block hole-type chilling block is completed perfectly.

It should be noted that the purpose of designing the single-piece chiller positioning hole and positioning pin is to facilitate the assembly of 12 chills, and they also play another important role in limiting expansion and contraction during the heating and cooling of the hole-type chiller, and play a role in preventing the deformation of the hole-type chiller. Because the hole and the pin are matched with each other in a small clearance, the hole and the pin need to be matched on site, and the matching clearance is about 0.10mm, so that the allowable deformation of the hole type chilling block assembly after assembly is controlled within a small range. Furthermore, the design position of the positioning hole is 25-35mm from the excircle (the matching surface with the inner hole of the roller die) of the hole type chiller to the center direction, and the positioning hole is far away from high-temperature iron (molten steel) and is heated to be relieved, so that the temperature rise time is prolonged, and the positioning pin can fully play a role of limiting the deformation of the chiller.

The hole-shaped chilling block is made of heat-resistant cast iron. The minimum deformation is realized on the material selection of the hole-shaped chilling block, and the material with the minimum deformation, namely the high-chromium cast iron, is finally determined through the trial of various materials.

The refractory coating is a necessary refractory interlayer for isolating the metal mould and high-temperature iron (molten steel) in the metal cavity, and has strict requirements on the coating: 1) The coating has high fire resistance. Generally, the casting temperature of the outer layer of the roller is 1350-1500 ℃ (the casting temperature of molten iron is the lower limit temperature, and the casting temperature of molten steel is the lower limit temperature), so only the coating with high refractoriness can withstand the scouring of high-temperature molten iron (steel). 2) The strength of the coating is high. During centrifugal casting, iron (steel) water is poured into a mold cavity rotating at a high speed through a special pouring gate (the rotating speed of a common mold is 800-1100 r/min), at the moment, an inner hole of a roller mold and a chilling block can be washed by the larger iron (steel) water under the action of centrifugal force, if the coating strength is low, the roller mold and the chilling block fall off during centrifugal casting, so that the iron (steel) water and the mold or the chilling block are directly contacted to cause adhesion, the mold is damaged finally, and the roller is scrapped. After a plurality of failures, the paint proportion and the brushing and hanging mode are determined.

The coating material proportion is as follows:

the coating brushing and hanging mode is as follows: the paint is brushed and hung by adopting a mode of turning grooves on a chilling block. When machining the hole-type chill, a groove with the width of 4mm and the depth of 2.5mm is turned on the inner side of the chill to reinforce the refractory coating. When the coating is brushed and hung, firstly, the coating is smeared on the surface with the groove, the diluted coating is brushed by a brush after the coating is smeared smoothly, and the coating is brushed again after the coating is aired to be semi-dry, and the surface is kept smooth without sand grains and pits. After the hole-type chill paint is brushed and hung, the hole-type chill paint is put into a drying kiln for preheating and drying, and then the inner surface of the roller die is coated with the film sand paint. At this point, the coating of the whole cavity is completely coated and is waited for pouring.

The design is found out through trial production for over ten years, and the centrifugal composite molded casting roller can be successfully produced in batch. As far as the so-called "centrifugal grooved casting" rolls have been applied at present, the content is totally only on the basis of the concept, without any operability, it is not possible to produce so-called "centrifugal grooved rolls" at all, since those operations have been tried and failed at all.

The process for producing the profile steel roller of the utility model can bring great benefits in the following aspects:

1. because the roll pass produced by the centrifugal composite profiled casting roll process adopts a chilling cooling forming method, the cooling speed of the upper part and the cooling speed of the lower part of the pass tend to be consistent, the crystal grains of the upper part and the lower part of the pass tend to be consistent, the thickness difference of the crystal grains is basically avoided, the hardness of the upper part and the lower part of the pass are basically the same, and the wear resistance is basically avoided. This results in a consistent overall wear resistance throughout the groove. Therefore, the difference of the wear resistance of the upper part and the lower part of the rolling groove is effectively eliminated, and the wear resistance of the whole rolling groove is greatly improved.

In addition, the cooling speed of molten metal is integrally increased by adopting the process, so that the integral roller grains tend to be refined, and the wear resistance of the rolling groove is further improved.

According to the prior trial-manufacture use record, on the premise of keeping the chemical components (pearlite nodular cast iron) of the same material, the roller produced by adopting the centrifugal composite molded casting roller process is used for rolling common carbon 4# angle steel, and the steel passing amount can be improved by 200-250% compared with the roller produced by adopting the common centrifugal composite casting roller process.

2. The process can greatly save the consumption of the outer layer high alloy molten iron (steel). In order to improve the wear resistance of the roller, the outer layer of the centrifugal roller is often made of a material with high alloy content, wherein the cast iron roller is made of more noble metals: nickel, molybdenum and the like, and the material cost of the outer layer molten iron is about 10000-13000 yuan/ton; the outer layer of the high-speed steel roll contains precious metals: nickel, molybdenum, niobium, vanadium, tungsten and the like, and the material cost of the outer layer molten steel is about 30000-35000 yuan/ton. The process can save the consumption of the external layer iron (steel) liquid by about 20 to 40 percent.

Table one: comparison table of advantages of centrifugal composite shaped casting and traditional centrifugal flat roll casting rolls for rough and medium roll of section steel, wire and bar

TABLE 1

Preparing and installing the hole-type chiller 20, referring to a roll hole pattern diagram, manufacturing a corresponding number of metal rings according to the number and size of rolling grooves 3 distributed on the same roll surface and the inner diameter of a roll die 10, cutting the metal rings into at least 8 fan-shaped chills 21 with the same size by wire cutting, forming a positioning hole 211 at the plane end of each two adjacent fan-shaped chills 21, and arranging an expansion groove 201 for expanding the hole-type chiller 20 between at least two adjacent fan-shaped chills 21; marking the installation position of the hole-type chilling block 20 on the inner hole of the clean roller die 10 by referring to the design size of the figure paper; positioning pins 212 are sequentially placed in the positioning holes 211 in sequence to assemble the hole-type chill, and finally the expansion pins 202 are driven into the expansion grooves 201 to be expanded to complete the installation of the hole-type chill; as shown in fig. 2, manufacturing an upper roll, wherein two hole-type chills 20 are installed in a roll die 10, the hole-type chills 20 are tightly attached to the inner wall of the roll die 10 after being matched and tightened with tightening grooves 201 through tightening pins 202, end covers 30 are fixed at two ends of the roll die 10, end cover molding sand 302 is arranged on the end covers 30, the end covers 30 are fixed by punching tapered end cover tightening pins 301 into end cover pin holes 102 uniformly arranged on the circumference of the end part of the roll die 10, and a roll die runway 101 on the roll die 10 is used for being matched with a centrifuge to enable the roll die 10 to rotate;

fig. 2 is an explosion diagram of the upper roll body molding device of the present invention, fig. 3 is an explosion diagram of the lower roll body molding device of the present invention, because the main difference between the upper roll and the lower roll is the diameter and the pass difference of the roll during molding, the upper roll and the lower roll can be molded by using the same set of roll mold 10, the inner diameter of the roll mold 10 is changed by setting the roll mold inner mold 103 in the roll mold to meet the size requirement of the lower roll, and the corresponding pass chill 20 is set in the roll mold inner mold 103 to mold the groove 3 on the lower roll, the pass chill 20 in the lower roll body molding device is also divided into 12 blocks for assembly, the same as the installation method in the upper roll, after finishing the outer layer casting and the middle layer casting, the roll mold 10 is hung to the bottom box 40 which is placed in advance for box assembling, the bottom box 40 is provided with molding sand 401, the riser box 50 is provided with riser sand 501 on the roll mold 10, and the riser box 50 is provided with riser sand 501 for casting of the lower roll;

as shown in fig. 4 and fig. 5, because the upper and lower rolls have slightly different structures, two hole-type chills 20 are arranged in the roll die 10 during the upper roll molding, and three hole-type chills 20 matched with the diameter of the roll die inner die 103 are arranged in the roll die inner die 103 during the lower roll molding;

as shown in fig. 6, the upper roll after casting is located in the molding device to form an upper roll blank 60, which includes symmetrical upper roll core upper roll neck 601 and upper roll core lower roll neck 602, and a middle upper roll core body 605, an upper roll intermediate layer 604 and an upper roll outer layer 603 are sequentially arranged outside the upper roll core body 605, and two grooves 3 formed by the cold iron with holes are formed on the upper roll outer layer 603.

As shown in fig. 7, the poured lower roll is located in a molding device to form a lower roll blank 70, which comprises an upper roll neck 701 and a lower roll neck 702 of a symmetrical lower roll core part, and a middle lower roll core part roll body 705, wherein a lower roll middle layer 704 and a lower roll outer layer 703 are sequentially arranged outside the lower roll core part roll body 705, and three grooves 3 formed by cold iron molding are formed on the lower roll outer layer 703.

As shown in fig. 8-11, which is a sectional view of a hole-type chiller, it includes 12 fan-shaped chills 21 formed by circular cutting, a positioning pin 212 is arranged between the plane ends of two adjacent fan-shaped chills 21 for connection and fixation, after 10 fan-shaped chills 21 are connected in sequence, an expansion groove 201 for expanding the hole-type chiller 20 is arranged between the last two fan-shaped chills 21, the other plane end of two fan-shaped chills 21 is provided with a positioning hole 211 matched with the positioning pin 212, so as to be able to continue to connect with the other 10 fan-shaped chills 21 to form a circular ring, and finally, the expansion groove 201 is formed by driving an expansion pin 202 into the expansion groove 201 to tightly attach the hole-type chills 21 to the inner side of the roller mold 10, the expansion groove 201 is formed by combining half expansion grooves respectively formed on two adjacent fan-shaped chills 21, and the expansion groove 201 is formed by sinking the outer circle of the fan-shaped chills; the expansion slots 201 can also be arranged among more adjacent fan-shaped chillers 21, and if the expansion slots 201 are arranged, the corresponding positioning holes 211 and positioning pins 212 arranged at the flat end are eliminated. Although theoretically a stronger expansion effect can be provided after the number of the expansion grooves 201 is increased, the expansion grooves are not beneficial to fixation, and the operation of repeatedly driving the expansion pins 202 also affects the roundness of the hole-type chill 20 in the roller die 10 and the uniform stress in the roller die 10, because the expansion pins 201 are driven in from the axial direction of the roller die 10 when being driven in, and are therefore perpendicular to the radial direction of the hole-type chill 20, in the expansion process, if the expansion pins 201 are repeatedly driven in, the hole-type chill 20 is easy to deviate from the original positioning position and move along the axial direction, the stress of the hole-type chill 20 is also complicated, and cannot be like theoretically only having extrusion force with the roller die 10, when the stress of the hole-type chill 20 is simpler, the hole-type chill 20 can be better kept when being tightly adhered in the roller die 10 through expansion, the stress of each part of the fan-shaped chill 21 can be uniform, and when being centrifugally cast, each fan-shaped chill 21 can be better limited, the deformation degree of the fan-shaped chill can be reduced, the process requirement can be met, and the process requirement can be repeatedly used; if the number of the expansion pins 202 is too large, the fan-shaped chiller 21 can slightly move along the axial direction, and the movement can be limited by the positioning pins 212, which is reflected on the hole-shaped chiller 20 and is equivalently obliquely arranged inside the roller die 10, so that the fan-shaped chiller 21 can also receive axial friction force, and the force is mainly counteracted by the positioning pins 212, so that the fan-shaped chiller is influenced by stress before centrifugal casting, and the influence can be amplified by cold and hot changes in the casting process, so that the deformation of the fan-shaped chiller 21 is difficult to be effectively controlled, the positioning and deformation limiting failures are caused, the positioning pins 212 are subjected to more obvious plastic deformation, and the demolding difficulty is increased.

The inner side of the hole-type chiller 20 is provided with a plurality of grooves 213, the cross section of each groove 213 is in an inverted triangle shape, and the bottom angle of each groove is in an arc shape. Can make things convenient for the connection stability of hanging the brush and promoting the coating of coating through slot 213, avoid the separation problem of coating when centrifugal casting.

The above mentioned is only the embodiment of the present invention, and not the limitation of the patent scope of the present invention, all the equivalent transformations made by the contents of the specification and the drawings, or the direct or indirect application in the related technical field, are included in the patent protection scope of the present invention.

Claims (10)

1. Split type pass chiller, its characterized in that: the hole-type chilling block comprises a hole-type chilling block which is formed by combining at least 8 fan-shaped chilling blocks and then expanding and tightly arranging an annular structure on the inner wall of a metal mold so as to limit the deformation of the fan-shaped chilling block; the hole-type chiller is provided with at least one expansion groove for expanding the fan-shaped chiller; and an expansion pin is arranged in the expansion groove.

2. The split hole type chiller according to claim 1, wherein: the metal mold is a roller mold or a roller mold internal mold arranged in the roller mold and used for changing the inner diameter of the roller mold.

3. The split hole type chiller according to claim 1, wherein: the hole-type chiller is cut into 12 fan-shaped chills by a metal ring wire.

4. The split hole type chiller according to claim 1, wherein: and the plane end of each fan-shaped chiller is provided with a positioning hole for positioning the adjacent fan-shaped chills.

5. The split hole type chiller according to claim 4, wherein: the positioning hole is arranged close to the outer circular arc of the fan-shaped chilling block.

6. The split hole type chiller according to claim 4, wherein: the distance between the positioning hole and the outer circular arc of the fan-shaped chilling block is 25-35mm.

7. The split hole type chiller according to claim 1, wherein: and an expansion groove for expanding the hole type chilling block is arranged between at least two adjacent fan-shaped chilling blocks.

8. The split hole type chiller according to claim 1 or 7, wherein: the expansion slot is wedge-shaped; the expansion pin is a wedge pin.

9. The split hole type chiller according to claim 1, wherein: and grooves for reinforcing refractory coatings are arranged on the inner sides of the fan-shaped chillers.

10. The split hole type chiller according to claim 9, wherein: the cross section of the groove is in an inverted triangle shape, and the bottom angle of the groove is in an arc shape.

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