JPWO2013108417A1

JPWO2013108417A1 - Crushing device and metal roll for grit production

Info

Publication number: JPWO2013108417A1
Application number: JP2012058081A
Authority: JP
Inventors: 政行石川; 可也中野
Original assignee: 新東工業株式会社
Priority date: 2012-01-16
Filing date: 2012-03-28
Publication date: 2015-05-11
Anticipated expiration: 2032-03-28
Also published as: WO2013108417A1; CN103379960B; CN103379960A; IN2014CN03542A; JP6021044B2

Abstract

The present invention provides a crushing apparatus for manufacturing a grit that can operate with a single driving source and stably crush a metal material while maintaining high durability. The present invention is a grit manufacturing crushing apparatus for manufacturing a grit by crushing a metal material between a pair of metal rolls (16, 18) that are rotatably arranged in parallel. One of the metal rolls is a drive roll (16) rotated by a drive source (66) connected by a drive belt (74), and the other metal roll is a driven roll (18). The driven roll (18) is disposed between the drive roll (16) and the drive source (66) in a plane parallel to the track plane of the drive belt (74).

Description

The present invention relates to a crushing apparatus and a metal roll for manufacturing a grit, and in particular, relates to a crushing apparatus for manufacturing a grit used for blasting, cutting stones, and the like, and a metal roll incorporated in such a crushing apparatus. .

Metal particles such as grit are used as a projection material used in blasting and the like. As a device for manufacturing such a projection material, a metal material for producing grit (metal) between the opposing outer peripheral surfaces of the metal roll while rotating a pair of crushing metal rolls arranged so that the outer peripheral surfaces face each other. A roll crusher (grid manufacturing apparatus) that supplies a grain to form a grid by crushing the metal material is generally and widely known.

In general, steel shot is used as a metal raw material for grit production, but a coarse grit screened from a grit produced by crushing may be used as a metal raw material for grit production.

For example, Patent Document 1 discloses a grit manufacturing apparatus that manufactures grit by crushing a shot with a crusher 12 (roll crusher).
Patent Documents 2 to 4 describe the production of grit using a roll crusher.
As described above, a grit manufacturing apparatus (roll crusher) that crushes a metal shot by rotating a pair of crushing metal rolls is known, and such a roll crusher is widely used as an apparatus having the highest crushing efficiency. It is clear that

In Patent Document 5, two metal rolls for crushing are respectively supported by a fixed bearing seat and a sliding bearing seat, and a spring is disposed between the fixed bearing seat and the sliding bearing seat. An opposing roll type grit manufacturing crushing apparatus is disclosed in which each of two crushing metal rolls is connected to a motor via a transmission belt.

Japanese patent JP 10-180633 A Chinese patent CN1846864A Chinese patent CN10362933A Chinese patent CN10362934A Chinese utility model CN2014445970U

In the grit crushing device (roll crusher) disclosed in the above-mentioned patent document or the like, the amount of the metal material supplied between the pair of metal rolls may temporarily increase for some reason. When such an increase in the supply amount occurs, the metal material (raw material shot) becomes a lump and is not crushed between the pair of metal rolls, but is pushed between the outer surfaces of the pair of metal rolls, so-called “biting” May occur.

This “biting” generates a shocking force that separates the pair of metal rolls, and increases the distance between the two metal rolls, thereby impeding stable pulverization.

However, the grit crushing device (roll crusher) disclosed in the above patent document or the like has two pieces when an impact force that separates the pair of metal rolls is generated due to such “biting”. No mechanism is provided that functions to maintain the spacing between the metal rolls.

For this reason, in the grit crushing device (roll crusher) disclosed in the above-mentioned patent document or the like, when "biting" occurs, the interval between the two metal rolls is widened and stable crushing can be performed. There was a problem of disappearing.

Further, in the structure described in Patent Document 5, when such “biting” occurs, both the fixed bearing seat and the sliding bearing seat 4 are elastically deformed to absorb the impact, When "biting" occurs, there is a problem that a large force acts on the fixed bearing seat, the sliding bearing seat, the bearing and the like, and the life of these members is shortened.

In addition, the structure described in Patent Document 5 requires two drive sources (motors), which increases the cost.

Furthermore, in the structure described in Patent Document 5, a spring is provided between the fixed bearing seat and the sliding bearing seat that supports each of the pair of metal rolls so that the two crushing metal rolls do not collide violently with each other. Since they are arranged, the force in the direction in which the pair of metal rolls are brought close to each other is canceled by the spring, and there is a problem that the crushing force becomes weak.

Furthermore, the grit crushing device (roll crusher) disclosed in the above-mentioned patent documents etc. is produced by crushing because the grit producing raw material is crushed between a pair of crushing metal rolls. The outer periphery of the metal roll is severely eroded by the applied grit, and wear of the outer periphery of the metal roll proceeds.

For this reason, in order to improve the wear resistance of the metal roll for crushing, various types of carbon steel for machine structure, alloy steel for machine structure, carbon tool steel, alloy tool steel, or these can be used as materials for the metal roll for crushing. Attempts have been made to adjust the hardness and toughness by improving the wear resistance by using cast steel having a chemical composition similar to that of the steel material and further performing heat treatment such as quenching and tempering.

However, since the metal roll for crushing is a large part having a weight of about several hundred kg and a wall thickness of 60 mm or more, quenching is likely to occur by quenching, and a uniform hardness distribution can be obtained. Since it was difficult, there was a problem that the wear was uneven.

The present invention has been made to solve the above-described problems, and can be operated with a single drive source, and can be stably crushed metal material while maintaining high durability. An object is to provide an apparatus.

Furthermore, it aims at providing the metal roll for crushing used with the crushing apparatus for grit manufacture excellent in abrasion resistance provided with moderate hardness and toughness.

According to the present invention,
A grit production crushing device for crushing a metal material between a pair of metal rolls arranged in parallel to be rotatable to produce grit,
One of the metal rolls is a drive roll that is rotationally driven by a drive source connected by a drive belt, and the other of the metal rolls is a driven roll,
The driven roll is disposed between the drive roll and the drive source in a plane parallel to the track plane of the drive belt;
The grit manufacturing crushing apparatus characterized by this is provided.

According to such a configuration, since the drive source is single, the apparatus can be reduced in size and the manufacturing cost can be reduced.

In addition, when the metal roll to be rotationally driven is called a driving roll and the other one is called a driven roll, the driven roll also rotates due to the frictional force with the driving roll, so it is not necessary to provide two rotational driving means, rather the driving roll And the difference in rotational speed of the driven roll, shear stress acts on the raw material for grit production, improving the crushing efficiency and increasing the yield rate.

Further, since the driven roll is arranged between the drive roll and the drive source in a plane parallel to the raceway plane of the drive belt, the grit is produced between the two metal rolls. When an impact force that widens the distance between the metal rolls due to the “biting” of the raw material is generated, the belt tension increases, so that the belt does not run and stable crushing can be realized.

Both the drive roll and the driven roll have a structure that does not have a radial edge that protrudes to the outside. The problem that the cost for manufacturing the metal roll for the use increases can be solved.

According to another preferred embodiment of the invention,
At least one of the metal rolls has a rotating shaft supported by a bearing box,
It is provided that the bearing box is configured to be slidable in a direction orthogonal to the rotation axis by pressure adjusting means connected to the bearing box.

According to such a configuration,
Since the pressing force between the metal rolls can be set by the pressure adjusting means, adjustment according to the particle size of the raw material for grit production becomes possible.

Furthermore, when an impact force is applied between the two metal rolls so that the grit manufacturing raw material bites into and widens the distance between the metal rolls, the metal roll moves in the direction in which the distance increases. Therefore, the load applied to the bearing and the bearing box is reduced and the durability is improved.

According to another preferred embodiment of the invention,
The sliding direction of the bearing box is the horizontal direction.

According to another preferred embodiment of the invention,
The pressure adjusting means includes an elastic body box and an elastic body fixture,
The elastic body box is filled with an elastic body selected from a spring, air, water and oil inside a deformable outer container,
The elastic body box is installed between the bearing box and the bracket, and is supported and fixed by an elastic body fixing tool attached to the bracket.

According to such a configuration,
Since the elastic box has a simple structure in which an elastic body is enclosed, the apparatus can be downsized.

According to another preferred embodiment of the invention,
At least the other of the metal rolls has a rotating shaft supported by a bearing box,
Position adjustment means for adjusting the position in the horizontal direction perpendicular to the rotation axis of the metal roll is connected to the bearing box of the other metal roll.

According to such a configuration, since the pressing force between the metal rolls can be arbitrarily set by the position adjusting means, adjustment according to the particle size of the raw material for grit production is possible.

According to another preferred embodiment of the invention,
The position adjusting means is one of a bolt, an air cylinder, a hydraulic cylinder, and an electric cylinder,
It is installed between the bearing box and the bracket.

The pair of metal rolls are installed in a housing fixed to a frame,
A raw material supply mechanism for supplying a grit manufacturing raw material to the metal roll is provided at an upper portion of the housing, and the raw material supply mechanism receives a raw material chute for supplying the raw material between the pair of metal rolls from the outside. And a raw material dispersing table for dispersing the raw material on the raw material dispersing table in the axial direction of the metal roll.

According to such a configuration, since the raw material for grit production spreads uniformly in the axial direction along the metal roll and is supplied to the metal roll, uneven wear of the metal roll is reduced and durability is improved.
Further, since the wear of the metal roll progresses uniformly, the problem that the grit manufacturing raw material falls without being crushed from the gaps in the uneven wear portion is greatly reduced, and the yield rate is improved.

According to another preferred embodiment of the invention,
The raw material dispersing means is a vibration generator driven by electric power or compressed air.

According to another preferred embodiment of the invention,
The pair of metal rolls, at least the outer peripheral surface is composed of high manganese cast steel,
The chemical composition of the high manganese cast steel is mass%, C: 0.8 to 1.5, Mn: 11 to 33, Cr: 1 to 4, Si: 0.8 or less, and the balance is Fe and inevitable impurities.

When high manganese cast steel is used, a metal roll for crushing having an appropriate hardness and toughness and excellent wear resistance is provided.
And the high manganese cast steel as described above has a base structure of retained austenite with excellent toughness, and only the surface portion where impact is applied during use is transformed into a martensite structure by work hardening and excellent wear resistance. It has toughness and is suitable as a metal roll material.

According to another preferred embodiment of the invention,
The pair of metal rolls, at least the outer peripheral surface is composed of high manganese cast steel,
The chemical composition of the high manganese cast steel is% by mass, C: 0.9 to 1.3, Mn: 11 to 14, Cr: 1.5 to 2.5, Si: 0.8 or less, the balance being Fe and inevitable It is an impurity.

Such a high manganese cast steel is more preferable because it has a low current material cost and a high ease of machining.

According to another aspect of the present invention, there is provided a metal roll used in a crushing apparatus for manufacturing a grit that crushes a metal material between a pair of metal rolls that are rotatably arranged in parallel to produce a grit,
A step of blending and melting raw materials of high manganese cast steel to prepare a molten metal at 1660 to 1720 ° C .;
Casting the molten metal into a mold;
The process of performing mold separation after cooling the casting and removing the casting,
A step of removing and removing the mold material adhering to the casting,
A process of removing weirs and hot water other than the cast product part;
A step of feeding the casting product part to a heat treatment furnace of 200 ° C. or less and then increasing the temperature from 1040 to 1060 ° C. at a temperature increase rate of 60 ° C./hour and holding at 1040 to 1060 ° C. for 2 to 4 hours;
A process of carrying out a water toughness treatment that is taken out of the heat treatment furnace, immersed in a water tank and rapidly cooled,
A step of removing the oxide film generated by the heat treatment by polishing;
There is provided a metal roll manufactured by a process of machining a cast product part to a specified size.

ADVANTAGE OF THE INVENTION According to this invention, the crushing apparatus for grit manufacture which can operate | move with a single drive source and can perform the stable crushing of a metal material, maintaining high durability is provided.
Furthermore, the metal roll for crushing used with the crushing apparatus for grit manufacture excellent in abrasion resistance provided with moderate hardness and toughness is provided.

It is a schematic front view of the crushing apparatus for grit manufacture of preferable embodiment of this invention. It is the schematic right view which fractured | ruptured a part of crushing apparatus for grit manufacture. It is the top view which fractured | ruptured a part in the state which removed the housing of the crushing apparatus for grit manufacture. It is the schematic which shows the structure of the pressure adjustment means used with the crushing apparatus for grit manufacture of FIG. It is the schematic which shows the structure of another pressure adjustment means.

Hereinafter, with reference to drawings, the crushing apparatus 10 for grit manufacture of preferable embodiment of this invention is demonstrated.
FIG. 1 is a schematic front view of a crushing apparatus 10 for manufacturing a grit according to a preferred embodiment of the present invention, and FIG. 2 is a schematic right side view in which a part of the crushing apparatus 10 for manufacturing a grit is broken. FIG. 3 is a plan view in which a part of the grit producing crushing apparatus 10 is removed with the housing removed.

The crushing apparatus 10 for manufacturing a grit according to this embodiment has a pair of columnar metal rolls 16 and 18 arranged in a parallel manner (supported) so that the outer peripheral surfaces are in contact with each other in the housing 14 at the top of the frame 12. The grit manufacturing raw material is supplied between the outer peripheral surfaces of the pair of metal rolls 16, 18, is crushed between the pair of metal rolls, becomes grit, and is discharged below the metal rolls 16, 18. It is what you have.

As shown in FIGS. 1 to 3, in the crushing apparatus 10 for manufacturing a grit, a drive roll 16 and a driven roll 18 constituting a pair of metal rolls 16 and 18 are disposed in a housing 14 provided on a frame 12. And are rotatably supported.

Each of the pair of metal rolls 16 and 18 includes substantially cylindrical outer peripheral portions 16a and 18a, and the outer peripheral portions 16a and 18a are made of high manganese cast steel. The outer peripheral portions 16a and 18a may have other configurations as long as at least the outermost layer surface is made of high manganese cast steel.
As a high manganese cast steel used for the metal rolls 16 and 18 of the crushing apparatus for grit manufacture of this embodiment, for example, a chemical component is mass%, C: 0.8-1.5, Mn: 11-33. , Cr: 1 to 4, Si: 0.8 or less, the balance being Fe and inevitable impurities. Further, C: 0.9 to 1.3, Mn: 11 to 14, Cr: 1.5 to 2.5, Si: 0.8 or less, and the balance may be Fe and inevitable impurities.

The grit manufacturing crushing apparatus 10 includes a raw material supply mechanism that supplies a metal raw material (metal particles), which is a raw material for grit manufacturing supplied from a raw material hopper (not shown), to the metal rolls 16 and 18 above the frame 12. Yes.
The raw material supply mechanism includes a raw material dispersion base 20 that receives a metal raw material from an external device such as a raw material hopper, a raw material chute 22 that receives the metal raw material from the raw material dispersion base 20 and supplies between the pair of metal rolls 16 and 18, and a metal material Dispersing means 24 is provided.

The raw material dispersion device 24 has a function of dispersing the metal raw material on the raw material dispersion table 20 in the axial direction of the metal rolls 16, 18. In this embodiment, the raw material dispersion device 24 is a vibration generator driven by electric power or compressed air.
Further, as the raw material dispersion device 24, a rotary blade, a rotary brush or the like driven by external power may be used. Furthermore, it is good also as a raw material dispersion | distribution means replaced with a raw material dispersion | distribution apparatus by providing a some convex part in the surface where the raw material for grit manufacture of the raw material dispersion stand 20 flows. Furthermore, you may use a convex part together with a vibration generator.

With such a configuration, the metal particles supplied from the external device such as the raw material hopper to the portion indicated by the arrow in FIG. It is supplied to the raw material chute 22 while uniformly spreading in the axial direction of the metal rolls 16 and 18 (direction perpendicular to the paper surface of FIG. 1) by vibration from the device 24. The metal particles supplied to the raw material chute 22 are supplied between the metal rolls 16 and 18 almost uniformly in the axial direction of the metal rolls 16 and 18 and are crushed.

Thus, since the raw material for grit manufacture is uniformly spread and supplied in the width direction of the axial rolls of the metal rolls 16 and 18, the uneven wear of the outer peripheral surfaces 16a and 18a of the metal rolls 16 and 18 is reduced and durable. Improves.
Further, since the wear of the metal roll proceeds uniformly, the problem that the grit manufacturing raw material falls without being crushed from the gaps in the uneven wear portion is greatly reduced, and the yield rate is improved.

Next, a support mechanism for the pair of metal rolls 16 and 18, that is, the drive roll 16 and the driven roll 18 will be described.
A drive shaft 26 and a driven shaft 28 are fixed at the radial centers of the drive roll 16 and the driven roll 18, respectively. Both ends of the drive shaft 26 and the driven shaft 28 protrude from both side surfaces of the drive roll 16 and the driven roll 18 and are rotatably supported by bearings 32 stored in bearing boxes 30 and 31.

The bearing box 30 that supports the drive shaft 26 of the drive roll 16 is fitted and fixed to the drive side position adjusting slide 34 as shown in the broken portion in FIG. The drive side position adjusting slide 34 is fixed to the drive side slide block 36 with bolts. Further, the slide block 36 is slidably supported by the drive side slide plate 38.
As a result, the drive shaft 26 of the drive roll 16 is configured to be slidable in a direction approaching and separating from the driven shaft 28 of the driven roll 18 (a direction perpendicular to the paper surface in FIG. 2).

A gap (not shown) extending in the vertical direction is provided between the drive side position adjustment slide 34 and the drive side slide block 36, and the bolt connecting the drive side position adjustment slide 34 and the drive side slide block 36. By adjusting this, the axial position of the drive roll 16 can be finely adjusted.

The driven roll 18 is also supported by the driven side position adjusting slide 34 ′, the driven side slide block 36 ′ and the like in the same manner as the drive roll 16 side.

Next, the overall structure of the frame 12 will be described.
As shown in the partial cross-sectional views of FIGS. 1 and 2, in the grit manufacturing crushing apparatus 10, a mounting base 40 for mounting the metal rolls 16, 18 on the frame 12 is fastened with bolts. Further, the lower base 42 is fastened with bolts on the mounting base 40, and the upper base 44 is fastened with bolts to the lower base 42 via the distance block 46.

A hole for passing a tie bar 48 is formed in the upper base 44 and the lower base 42, and the tie bar 48 passes through the hole. Brackets 54 and 56 are attached to both ends of the tie bar 48 via spacers 50 and 52, and nuts 58 are fastened from outside the brackets 54 and 56.

Further, on the upper surface of the lower base 42, the drive side slide plate 38 is replaceably attached to the drive roll 16 side, and the driven side slide plate 60 is replaceably attached to the driven roll 18 side.

In the crushing apparatus 10 for grit production, as shown in FIG. 3, the driving roll 16 and the driven roll 18 taper inward in the axial direction so that the inner diameters at both ends in the axial direction are maximized. It has substantially cylindrical outer peripheral portions 16a and 18a that form an internal space.

In this internal space, roll fixtures 62 tapered to a shape that is compatible with the internal space are inserted from both ends in the axial direction, and the roll fixtures 62 on both sides are connected by roll connectors 64 such as bolts. ing. The roll fixing tool 62 is fitted to the drive shaft 26 and the driven shaft 28, so that the drive roll 16 and the driven roll 18 are coupled to the drive shaft 26 and the driven shaft 28.

In the crushing apparatus 10 for manufacturing a grit according to this embodiment, when the outer peripheral surfaces of the drive roll 16 and the driven roll 18 are worn, only the substantially cylindrical outer peripheral portions 16a and 18a can be replaced.

Next, a rotation drive mechanism that rotates the drive roll 16 will be described.
As shown in FIGS. 1 and 3, in the grit manufacturing crushing apparatus 10 of this embodiment, a drive shaft pulley 65 is fixed to one end portion of the drive shaft 26 of the drive roll 16.

On the other hand, a motor 66 serving as a drive source for the drive roll 16 is fixed on an installation base 68 fixed on the frame 1. A motor shaft pulley 72 is fixed to the output shaft 70 of the motor 66. A drive belt 74 is wound around the drive shaft pulley 65 and the motor shaft pulley 72, and the rotation of the output shaft 70 of the motor 66 is transmitted to the drive shaft pulley 65.
In this embodiment, a so-called power transmission belt in which an outer cloth is covered on a rubber core material is used as the drive belt 74, but other types of drive belts can also be used.

The motor 66 is disposed on the opposite side of the drive roll 16 with the driven roll 18 in between. That is, the driven roll 18 is disposed between the drive roll 16 and the motor 66 in a plane parallel to the track plane of the drive belt 74.

With such a structure, during the grit manufacturing operation, a “biting” of the raw material for grit production occurs between the drive roll 16 and the driven roll 18, and the force to widen the gap between the drive roll 16 and the driven roll 18 is increased. When this occurs, a force in the direction opposite to the motor 66 acts on the drive roll 16 to increase the tension of the drive belt 74. As a result, the driving roll 16 is pressed toward the driven roll 18 and stable crushing can be realized without idling.

Moreover, in the crushing apparatus 10 for grit manufacture of this embodiment, since the follower roll 18 is a structure rotated with the frictional force with the drive roll 16, an apparatus can be operated by one drive source (motor). Therefore, it has become possible to reduce the size of the device and reduce the manufacturing cost.
Furthermore, since the shear stress acts on the grit manufacturing raw material due to the difference in rotational speed between the drive roll 16 and the driven roll 18, the crushing efficiency is improved and the yield rate is improved.

In the crushing apparatus 10 for manufacturing a grit according to the present embodiment, the driven roll 18 rotates by frictional contact with the drive roll 16 as described above, and thus it is necessary to adjust the pressing force between the rolls.
Further, when an impact force is generated between the drive roll 16 and the driven roll 18 to increase the gap between the rolls due to the “biting” of the grit manufacturing raw material, the bearing 32 and the bearing boxes 30 and 31 Since an excessive load acts, a structure for reducing this load is required.

For this reason, in the crushing apparatus 10 for grit manufacture of this embodiment, the drive roll 16 and the driven roll 18 are rotatably supported by the bearing boxes 30 and 31 and are orthogonal to the rotation axis along the slide plates 38 and 60. The load is reduced by supporting the slidable member in the direction of sliding.

In this embodiment, a pressure adjusting means acting in a horizontal direction perpendicular to the drive shaft 26 is connected to the bearing box 30 supporting the drive roll 16, and the bearing box 31 supporting the driven roll 16 is orthogonal to the roll axis. Position adjusting means 76 for adjusting the horizontal position is connected.

The pressure adjusting means includes an elastic body box 78 and an elastic body fixture 80. The elastic body box 78 has a structure in which any one elastic body selected from a spring, air, water, and oil is enclosed in a deformable outer container. The elastic body box 78 is installed between the bearing box 30 that supports the drive roll 16 and the drive side bracket 54, and is supported and fixed by an elastic body fixture 80 attached to the drive side bracket 54.
Thus, since the elastic body box 78 can be made into a simple structure in which an elastic body is enclosed, the apparatus can be miniaturized.

FIG. 4 shows the structure of pressure adjusting means using a spring as an elastic body enclosed in the elastic body box 78.
As shown in FIG. 4, in this pressure adjusting means, a spring 82 and a plate-like elastic body connector 84 are installed inside an elastic body box 78. The elastic body box 78 is a bellows-like structure that covers the spring 82 and the elastic body connector 84, and serves to protect the elastic body from dust, grit manufacturing raw materials, etc., and is made of resin, metal, cloth, etc. The produced bellows is used.

The spring 82 and the base end side (the right side in FIGS. 1 and 4) of the elastic body box 78 are connected to one surface of an elastic body connector 84 connected to the drive side bracket 54. Further, the distal end side (the left side in FIGS. 1 and 4) of the elastic body fixture 80 is connected and fixed to the other surface of the elastic body connector 84 through the hole provided in the drive side bracket 54. Yes.

With such a structure, the pressure adjusting means is disposed between the bearing box 30 that supports the drive roll 16 and the drive side bracket 54, and the bearing box 30 that supports the drive roll 16 supports the driven roll 18. The pressure pressed toward 31 is adjusted.

FIG. 5 shows a specific structure of the pressure adjusting means when water or oil is used as the elastic body instead of the spring 82.
In this example, a fluid spring 86 in which water or oil is filled in a deformable bellows structure container is installed in the elastic body box 78 ′. The base end side (the right side in FIGS. 1 and 5) of the fluid spring 86 is connected to the elastic body connector 84. Such an elastic body box 78 ′ is disposed between the bearing box 30 that supports the drive roll 16 and the drive side bracket 54, similarly to the configuration of FIG. 4.

As shown in FIG. 5, it is preferable that the fluid spring 86 can arbitrarily control the pressure by fluidly communicating with a fluid storage container 88, a pressure valve 90, an air pump 92, and the like.

The position adjustment means 76 is any one selected from a bolt, an air cylinder, a hydraulic cylinder, and an electric cylinder, and is installed between the driven-side bearing box 31 and the driven-side bracket 56.

When the driving roll 16 and the driven roll 18 are worn by the crushing operation, the driving roll 16 is pushed to the driven roll side by the pressing pressure from the pressure adjusting means, and the contact point between the both rolls 16 and 18 becomes the material chute. It will be displaced from the position just below 22 to the driven roll side. For this reason, the position adjustment means 76 presses the bearing box 31 of the driven roll 18 toward the drive roll to compensate the positions of the two rolls 16 and 18.

The position adjusting means 76 can have a simple structure by using bolts or various cylinders.

In addition, when the elastic body box 78 is the structure which enclosed air, water, and oil, external apparatuses, such as the pump for adjusting a pressure, the tank which stores a fluid, and a pressure adjustment valve, as needed. The pressure in the elastic body box 78 can be controlled by connecting to the elastic body box 78.

By such pressure adjusting means, a constant pressing force is always maintained between the rolls, and the position adjusting means 76 allows fine adjustment of the pressing force and position adjustment when the roll is worn. When a shocking force acts so as to widen the interval, an effect of reducing the load can be obtained by the pressure adjusting means.

Further, since the pressure adjusting means is connected to the bearing box 30 of the drive roll 16, a “grating” of the raw material for producing grit occurs between the drive roll 16 and the driven roll 18, so that the gap between the rolls is widened. When a shocking force is generated, the tension of the drive belt 74 increases, so that it does not run idle and stable crushing can be realized. Therefore, the load on the pressure adjusting means is temporary and minimal. Therefore, it is more preferable.

Further, since the position adjusting means 76 is on the side where the motor 66 is installed, there is an advantage that the apparatus does not increase in size even if various cylinders are used as the position adjusting means 76.

The grit manufacturing raw material crushed between the pair of metal rolls 16 and 18 flows downward from the discharge chute 94 and is temporarily stored in a hopper or the like (not shown).

Without being limited to the above-described embodiment of the present invention, various changes and modifications can be made within the scope of the technical idea described in the claims.

Next, examples of the present invention will be described.
An experiment was conducted to examine the material of the outer peripheral portion of the metal roll. The outer peripheral part of the metal roll was manufactured using the material shown in Table 1, and the wear resistance and impact resistance were compared.
Examples 1 to 3 are three types of high manganese cast steels having different chemical components. Comparative Examples 1-2 are two types of chromium molybdenum steels having different chemical components.
The chemical composition is the result of cutting a part of the prototype casting and measuring it by emission spectroscopy. The hardness was measured using a Rockwell hardness scale C scale (HRC), and the measurement method was carried out according to JISZ2245 (ISO 6508).

For the evaluation of wear resistance, a pair of rolls were actually manufactured, and the amount of wear after 100 hours of continuous operation using a steel shot of φ2 mm as a raw material was obtained from the weight loss and compared. In Table 1, the wear amount of Comparative Example 1 is represented as 100, and the smaller the value, the better the wear resistance. The impact resistance indicates the presence or absence of occurrence by examining the occurrence of cracks after 100 hours of continuous operation.

Compared with the hardness of the chromium molybdenum steel of Comparative Example 1, the hardness of the high manganese cast steel of Examples 1 to 3 is low, but this is the hardness before use, and the hardness of the outermost surface after use. When the thickness was measured with a micro Vickers hardness meter, it showed Hv 400 to 520, which was equivalent to HRC 40.8 to 50.5 when converted to Rockwell hardness. However, the work-hardened layer was as thin as about 0.5 mm from the surface, and the inside was the same hardness as before use. Therefore, in the case of the high manganese cast steels of Examples 1 to 3, the outermost surface is work hardened and is higher than the hardness of the chromium molybdenum steel of Comparative Example 1, and thus it is estimated that the wear resistance is improved.

Comparative Example 2 is an example in which the hardness was increased by increasing C and Si, and the hardness was the highest, but cracks occurred in the roll after use, and the toughness was insufficient. confirmed. The high manganese cast steels of Examples 1 to 3 are work hardened on the outermost surface and exhibit excellent wear resistance, and the inside is a highly tough structure composed of retained austenite, so that the possibility of generating cracks is low and safe. High nature.

In the case of the high manganese cast steels of Examples 1 to 3, the tendency that the hardness was slightly increased as Mn increased was observed, but the wear resistance was slightly decreased. Therefore, the chemical component of Example 1 is more preferable in view of the current material cost and ease of machining. Example 1 is a prototype using chemical components of JIS standard SCMnH11, and the target components are mass%, C: 0.9 to 1.3, Mn: 11 to 14, Cr: 1.5 to 2. 5, Si: 0.8 or less, the balance consists of Fe and inevitable impurities.

Next, it experimented about the method of manufacturing a metal roll with high manganese cast steel. High manganese cast steel contains a large amount of Mn, which is an element having a high affinity with oxygen, and therefore generally has poor hot-water flow and tends to cause defects such as hot water wrinkles and poor hot water in the casting. Therefore, in order to manufacture a sound casting, it is necessary to prepare a molten metal at about 1660 to 1720 ° C. in the melting step. In addition, the process of casting the molten metal into a mold, the process of removing the mold by casting the mold after cooling the casting, the process of removing and removing the mold material adhering to the casting, the weir and the hot water other than the casting product part After the cast product part manufactured through the step of removing the carbon steel was fed into a heat treatment furnace at 200 ° C. or lower, the temperature was increased from 1040 to 1060 ° C. at a temperature increase rate of 60 ° C./hour, and the temperature was increased from 1040 to 1060 ° C. at 2 to 4 A uniform retained austenite base structure is formed by a process of performing a water toughness treatment in which the mixture is heated uniformly by the time holding process and then taken out of the heat treatment furnace and immersed in a water bath and rapidly cooled. Furthermore, it was confirmed that the oxide film produced by the heat treatment can be manufactured by a step of removing the oxide film and a step of machining the cast product part to a specified size.

10: Crusher for manufacturing grit 12: Frame 14: Housing 16: Drive roll 18: Driven roll 20: Raw material dispersion table 22: Raw material chute 24: Metal material dispersion means 26: Drive shaft 28: Driven shaft 30: Bearing box 32: Bearing 66: Motor 74: Drive belt

Claims

A grit production crushing device for crushing a metal material between a pair of metal rolls arranged in parallel to be rotatable to produce grit,
One of the metal rolls is a drive roll that is rotationally driven by a drive source connected by a drive belt, and the other of the metal rolls is a driven roll,
The driven roll is disposed between the drive roll and the drive source in a plane parallel to the track plane of the drive belt;
A grit manufacturing crusher characterized by the above.
At least one of the metal rolls has a rotating shaft supported by a bearing box,
The bearing box is configured to be slidable in a direction orthogonal to the rotation axis by pressure adjusting means connected to the bearing box.
The crushing apparatus for grit manufacture according to claim 1.
The sliding direction of the bearing box is a horizontal direction,
The crushing apparatus for grit manufacture according to claim 2.
The pressure adjusting means includes an elastic body box and an elastic body fixture,
The elastic body box is filled with an elastic body selected from a spring, air, water and oil inside a deformable outer container,
The elastic body box is installed between the bearing box and the bracket, and is supported and fixed by an elastic body fixture attached to the bracket.
The crushing apparatus for grit manufacture according to claim 2.
At least the other of the metal rolls has a rotating shaft supported by a bearing box,
A position adjusting means for adjusting a horizontal position orthogonal to the rotation axis of the metal roll is connected to the bearing box of the other metal roll.
The crushing apparatus for grit manufacture according to claim 2.
The position adjusting means is one of a bolt, an air cylinder, a hydraulic cylinder, and an electric cylinder,
Installed between the bearing box and the bracket,
The crushing apparatus for grit manufacture according to claim 5.
The pair of metal rolls are installed in a housing fixed to a frame,
A raw material supply mechanism for supplying a grit manufacturing raw material to the metal roll is provided at an upper portion of the housing, and the raw material supply mechanism receives a raw material chute for supplying the raw material between the pair of metal rolls from the outside. A raw material dispersion stage for sending the raw material to the raw material chute while dispersing the raw material in the axial direction of the metal roll, and a raw material dispersion means for dispersing the raw material on the raw material dispersion stage in the axial direction of the metal roll
The crushing apparatus for grit manufacture according to claim 1.
The raw material dispersion means is a vibration generator driven by electric power or compressed air.
The crushing apparatus for grit manufacture according to claim 7.
The pair of metal rolls, at least the outer peripheral surface is composed of high manganese cast steel,
The chemical composition of the high manganese cast steel is% by mass, C: 0.8 to 1.5, Mn: 11 to 33, Cr: 1 to 4, Si: 0.8 or less, the balance being Fe and inevitable impurities.
The crusher for grit manufacture of any one of Claims 1-8.
The pair of metal rolls, at least the outer peripheral surface is composed of high manganese cast steel,
The chemical composition of the high manganese cast steel is% by mass, C: 0.9 to 1.3, Mn: 11 to 14, Cr: 1.5 to 2.5, Si: 0.8 or less, the balance being Fe and inevitable Is an impurity,
The crushing apparatus for grit manufacture of Claims 1-8.
A metal roll used in a crushing apparatus for grit production that crushes a metal material between a pair of metal rolls arranged in parallel to be rotatable to produce grit,
A step of blending and melting raw materials of high manganese cast steel to prepare a molten metal at 1660 to 1720 ° C .;
Casting the molten metal into a mold;
The process of performing mold separation after cooling the casting and removing the casting,
A step of removing and removing the mold material adhering to the casting,
A process of removing weirs and hot water other than the cast product part;
A step of feeding the casting product part to a heat treatment furnace of 200 ° C. or less and then increasing the temperature from 1040 to 1060 ° C. at a temperature increase rate of 60 ° C./hour and holding at 1040 to 1060 ° C. for 2 to 4 hours;
A process of carrying out a water toughness treatment that is taken out of the heat treatment furnace, immersed in a water tank and rapidly cooled,
A step of removing the oxide film generated by the heat treatment by polishing;
A metal roll manufactured by a process in which a cast product part is machined to a specified size.