JPH0420508Y2 - - Google Patents

Description

[Detailed description of the invention] [Field of industrial application] The present invention relates to a striker for an impact type crusher that crushes rocks, ores, etc. by impact. The present invention relates to a striker for an impact type crusher which aims to reduce damage to pieces of cemented carbide material attached to the machine.

[Prior art]

A conventional impact crusher is constructed as shown in a schematic cross-sectional view in FIG.

For example, raw ore is fed into the crushing chamber 3 from the raw material supply port 2 installed at the upper side of the impact crusher 1, and the raw ore is fed into the crushing chamber 3 by a blower fixed to the outer periphery of a rotating rotor 5 that rotates around a main shaft 4. Shattered by impact by 6.

The raw stone that is thrown off by the rotating rotor 5 collides with the liner 7 _a attached to the first repulsion plate 7 provided at the top of the crushing chamber 3 and is crushed.
The rebounding raw stone is crushed by impact by the next hammer 6 which rotates further. Then, the thrown ore is crushed even more finely by the liner 8 _a attached to the second repulsion plate 8 provided at the upper part of the crushing chamber 3 .

In the case of such a conventional impact type crusher, the impactor 6 formed as one piece is generally made of a hard metal material such as high chromium cast iron, high manganese cast steel, or chromium molybdenum cast steel.

However, with such a striker 6, since the supplied raw stone to be crushed also contains hard minerals, etc., if impact is repeated between it and the hard supplied raw stone, as shown in FIG. It will gradually wear out like this.

That is, as shown in FIG. 8A, the tip portion ₆ a of the striker 6 whose initial shape was as shown by the solid line.
gradually wears away and deforms into a rounded shape, as shown by the plurality of broken lines in FIG. 8B.

In the conventional impact type crusher, from the viewpoint that it is uneconomical to discard the impactor 6 in this state, the impactor 6 is turned over as shown in Fig. 8C, and the
Use continues until wear progresses as shown by the broken line in Figure D.

[Problem that the invention attempts to solve]

As described above, in conventional impact crushers, the impactor did not have sufficient wear resistance, so when the impactor wears and its tip becomes rounded, it becomes difficult for the object to be crushed to collide head-on. However, the disadvantages were that the crushing capacity decreased and the cost for replacement increased significantly. In addition, the frequency of replacement, including turning the front and back as described above, is important, for example, when crushing rocks for aggregate.
The work of replacing the hammer, which weighs approximately 100 kg, once every 1.5 to 3 months was extremely demanding.

In addition, in order to reduce the wear of the striking element, it is possible to attach a wear-resistant piece made of hard ceramics or cemented carbide to the tip of the striking element, but simply attaching such a wear-resistant piece will not reduce the wear resistance. There are other problems, such as the need to replace the entire impactor when a piece breaks, and the high cost of carbide material, which makes it uneconomical. has not been standardized.

Particularly when a piece of carbide material is used as a wear-resistant material, it is necessary to find a special structure that can prevent cracking since the carbide material is prone to cracking due to its hardness.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a striking element for an impact type crusher that has high wear resistance, is less susceptible to damage such as cracking, and is easy to replace when worn.

[Means for solving problems]

The main means adopted by the present invention to achieve the above object are: a rotating rotor that rotates around a main shaft provided inside a casing; The method comprises a plurality of striking elements and a repulsion plate provided at an appropriate distance around the rotating rotor, and causes the raw material splashed by the tip of the rotating striking element to collide with the tip of the striking element and the repulsion plate. In a striker for an impact type crusher that shreds by crushing, a piece of carbide material is brazed and joined to the tip of the striker or a joining table that is detachably attached to the tip of the striker, and at least the outermost portion of the carbide material is This is a striker for an impact type crusher in which the joint surfaces of the pieces are inclined at 3° to 25° in the rotational direction with respect to the radial direction of the rotating rotor.

[Effect]

Since the tip of the impactor, which has the highest impact, is made of carbide material, the cross-sectional shape of the impactor hardly changes even after long-term use, and a constant crushing ability can be maintained at all times. Conventional 7~
(necessary once every 10 days) is not necessary, and since the crushing element is solely responsible for crushing, the load on the crusher (liner wear) is significantly reduced.

Even if the piece of carbide material at the tip of the striker eventually wears out and the wear extends to the joint surface to the striker (or joint stand), the angle between the tangent of the worn surface and the joint surface at the joint surface portion will be as described above. Since the slope is large by 3° to 25°, no large concentrated stress is applied to the contact area between the bonding surface and the wear surface, and cracking or chipping of the cemented carbide material in this area is prevented.

In addition, if the joint base attached to the striking element is divided into multiple parts in the radial direction of the rotating rotor and/or in the direction of the main axis, it is possible to replace the worn carbide material piece or change the mounting direction. ,
There is no longer an uneconomical need to waste expensive pieces of carbide material.

When replacing or changing the orientation of such a piece of cemented carbide material, the striker must be removed together with the joint stand that is detachably attached to the rotating rotor. Therefore, unlike conventional large integrated striking elements, it can be easily replaced. As a result, even if the uneven wear in the width direction, which is observed in conventional striking elements, can be avoided by changing the position of the striking element, the striking element can be used without waste.

[Embodiments] Next, embodiments embodying the present invention will be described with reference to the attached drawings to provide an understanding of the present invention. Here, Fig. 1 relates to a striker according to an embodiment of the present invention, Fig. 1a is a side sectional view thereof, Fig. 2b is a front view (only the right half), and Figs. FIG. 1a showing a striking device according to another embodiment.
Corresponding views, FIGS. 3a and 3b are views corresponding to FIGS. 1a and b in a striker according to another embodiment, and FIGS. 4a,
b is a modified example of the striker shown in Fig. 3, and Fig. 2a,
Fig. 5, which corresponds to Fig. 2b, shows the state of damage to the chip when using a carbide chip in which the inclination angle θ of the joint surface of the striker and the minimum thickness t of the carbide chip shown in Fig. 2b are varied. The graph shown in FIG. 6 is a side view of a main part showing the progress of wear of the striking element shown in FIG. 3.

It should be noted that the following embodiments are merely examples embodying the present invention, and are not intended to limit the technical scope of the present invention.

In FIGS. 1a and 1b, the striker 10 includes a striker body 11 and a plurality of joint stands 14, 14, . and each joint table 14,1
4, respectively, and each joint base 14, 14... is removably fixed to the striking body 11 by bolts 17, 17,... has been done.

The joining of the carbide chip 15 to the joining table 14 is as follows:
It is soldered using sand German braze (a clad material made by sandwiching a copper plate between two pieces of silver solder). Also, for joining
Pressure fusion bonding using HIP, electron beam or laser welding, or other heat fusion methods may also be used.

The carbide chip 15 is an example of a piece of carbide material, and the spigot parts 13, 13, . . . prevent the joint tables 14, 14, . It is for the purpose of

The carbide chips 15, 15, . . . and the joining tables 14, 14, .
In the examples shown in FIGS. 1 and 2, one cemented carbide chip corresponds to one joining table. A plurality of carbide chips may be brazed to one joint table. Further, the carbide chip 15 and the joining table 14 can also be divided in the radial direction of the rotating rotor 5.

The material of the cemented carbide chip 15 includes all so-called cemented carbide alloys. In this way, cemented carbide is made of, for example, tungsten carbide WC as a base material, titanium carbide TiC, tantalum carbide TaC, niobium carbide NbC,
Contains a mixture of appropriate amounts of vanadium carbide VC, molybdenum carbide Mo ₂ C, titanium nitride TiN, etc., and cobalt as a binder.
Co is also widely used.

As a material for the carbide chip 15. For example, K20 (JIS
By selecting B 4104), we were able to achieve a lifespan ratio/cost ratio >1.

In the case of the striker 10 shown in this example, the wear life was more than six times that of the conventional striker made of 27Cr cast iron.
As long as the carbide chip 15 is a brittle material, there is no guarantee that it will never break, so the number of breaks corresponding to the throughput is predicted by calculating the probability of breakage in advance, taking into account the Weibull distribution of rock strength and carbide chip strength. We then carried out proof tests such as load tests to remove any carbide chips that were likely to break.

As a result, inconveniences such as irregular breakage of the chips during use were avoided, and it was also found that the number of carbide chips removed was extremely small, at just a few.

On the other hand, the particle size distribution of the product is at the initial shape of the carbide chip.
It was found that the crushing capacity remained constant as the carbide tips wore out, and there was no decrease in crushing ability.

The bonding surface 18 of the cemented carbide chip 15 to the bonding table 14 is inclined by θ° in the rotational direction with respect to the straight line 19 in the radial direction of the rotating rotor 5.

On the other hand, the fracture surface 20 of the carbide chip 15 is the first
In the case of the embodiment shown in the figure, it is parallel to the straight line 19 in the deformation direction of the rotating rotor 5. Therefore, in the side cross-sectional shape of the carbide chip 15, the width in the circumferential direction of the rotor 5 is wider toward the center of the rotor 5.
It is formed in a so-called fan shape.

What is shown in FIG. 2 is a modification of the striker 10 shown in FIG. 1 above, and the striker 10 _b shown in FIG.
Unlike the carbide chip 15 shown in FIG. 1, the fracture surface _20a and the bonding surface _18a are parallel. However, this embodiment is similar to the embodiment shown in FIG. 1 in that the joint surface _18a is inclined in the direction of rotation of the rotating rotor 5 by an angle of inclination θ.

When such a striking element 15 is used for a long period of time, wear progresses as shown in FIG. That is, as the crushing operation continues, the tip corner of the carbide chip 15 first wears out as shown by the broken line (wearing surface) a, and eventually the wear extends to the joint surface 18 b. At this time,
Broken lines also apply to the joining table 14 and the striking body 11.
It wears out as shown by b′. If the use is continued in this state, the carbide tip 15 will eventually reach the dotted line c,
It wears out as shown in d, e, f, and g, and the joint base 14 and the striking element body 11 wear out as shown in c', d', e', f', and g'.

At this time, for example, the size of the angle φ formed by the tangent 22 from the contact point 21 of the wear surface c and the joint surface 18 to the wear surface c and the joint surface 18 is
The larger the inclination angle θ of 8, the larger the angle becomes. Concentrated stress is likely to be applied to such a contact point 21 due to collision of raw materials, but the carbide chip 1 at the contact point 21
The larger the end angle φ of 5, the more this stress concentration is alleviated.

Therefore, by tilting the joint surface 18 in the direction of rotation of the rotating rotor 5 as in the present invention, the contact point 21
Cracking and chipping of the carbide chip 15 at the portions are reduced.

The minimum thickness t of the carbide chip 15 also has a large influence on such cracks and chips of the carbide chip 15. This is because when raw rock collides with the carbide chip 15, if the impact force is P and the thickness of the carbide chip is t, the tensile stress σ generated on the collision surface is σ=k(P/t ² ). Here k is a constant. Therefore, the smaller the minimum thickness t of the carbide chip 15, the greater the tensile stress σ.
Cracks and chips of the carbide chip 15 occur frequently.

FIG. 5 shows the minimum thickness t of the carbide tip _15a and the bonding surface 1 for the striker shown in FIG. 2b.
₈ Carbide chips 15 _a when crushing tests were conducted on carbide chips with various inclination angles θ
This shows the state of cracks and chips. The experimental conditions in this case were a rotor circumferential speed of 28 m/s, a raw material rock size of 50 to 0 mm, a production rate of 140 t/h, and K20 was used as the material for the carbide chips _15a .

In FIG. 5, ◯ indicates a condition in which no cracking or chipping occurs in the carbide chip, and △ indicates a condition in which some chipping occurs but there is no problem with continued use. Also, ● indicates conditions where the carbide chip is severely damaged and cannot be used.

As is clear from Figure 5, the inclination angle θ exceeds 3°.
Although some chipping occurred due to the addition of , we were able to obtain a carbide chip with almost no problems in use. Also, as long as the inclination angle θ exceeding 3° is maintained as described above, the thickness t of the carbide chip is 5°.
It was found that if it was more than mm, it could be used. However, if the minimum thickness of the carbide chip is 3 mm, some chipping will occur in all angle ranges even if the inclination angle θ exceeds 3 degrees, and if t is 2 mm, it cannot be used under all experimental conditions. Unbearable damage occurred.

However, if the above-mentioned inclination angle θ exceeds 25°, although the carbide chip will not break or crack, the raw material rock thrown off by the crushing surface _20a will be crushed by the back surface of the adjacent striking element. It has been found that it is practically difficult for the above-mentioned inclination angle θ to exceed 25° because this results in collision with the base material and wear.

Next, as can be easily understood from the wear curves a to g shown in FIG. It is well understood that the parts do not experience much wear. Therefore, the carbide tip 1
As shown in FIG.
...The thickness of the carbide chip can be maintained at a certain level or above without cracking or chipping even when it wears down from e → f → g, making it possible to create a carbide chip that can withstand long-term use. It is understood that this may be provided.

What is shown in FIG _. 2a is a structure in which the carbide chip 15 and the joint table 14 shown in _FIG . If the end is worn as shown by the broken line h, loosen the bolt _17b and
By turning the carbide tip _15b upside down, it can be used until the wear surface shown by _the broken line h' is formed on the opposite side of the carbide tip _15b . It can be extended over a long period of time.

3 and 4, the joining tables 14, _14a , _14b in FIGS. 1 and 2 are omitted, and the carbide chips _15c , _15d , _15e (respectively 15,
15 _a , 15 _b ) directly into the striking body 11.
_c , _11d , and _11e are brazed. Such a hammer is suitable for use in sand making, etc., where there is relatively little wear.

[Effect of idea]

As described above, the present invention includes a rotating rotor that rotates around a main shaft provided inside a casing, a plurality of strikers fixed to the outer periphery of the rotating rotor, and a plurality of strikers arranged around the rotating rotor. A striker for an impact crusher, which is equipped with a repulsion plate provided at a distance, and crushes the raw material splashed by the tip of the rotating striker by colliding with the tip of the striker and the repulsion plate, The cemented carbide material pieces are heat-fused and bonded to the tip of the striker or a joining table that is detachably attached to the tip of the striker, and at least the bonding surface of the outermost piece of carbide material is rotated with respect to the radial direction of the rotating rotor. Since this is a striker for impact type crushers that is tilted 3° to 25° in the direction of the direction, the use of a piece of carbide material at the tip of the striker dramatically increases the lifespan. Since the structure is such that stress concentration does not occur even when the carbide material piece is deformed due to wear, it is possible to prevent the carbide material piece from cracking, significantly extending the life per cost of the carbide material piece. It was a success.

[Brief explanation of drawings]

FIG. 1 shows a striker according to an embodiment of the present invention; FIG. 1a is a side sectional view thereof, FIG. A view corresponding to FIG. 1a showing the striking element according to the embodiment,
Figures 3a and b are views corresponding to Figures 1a and b in a striker according to another embodiment, and Figures 4a and b are views of the third striker.
A modified example of the striker shown in the figure, which corresponds to FIGS. 2a and 2b, and FIG. Fig. 6 is a side view of the main part showing the progress of wear of the impactor shown in Fig. 3, and Figs. 7 is a side sectional view thereof, and FIG. 8 is an explanatory diagram showing the progress of wear of a conventional impacting element. Explanation of symbols, 10...Batterer, 11...Batterer body, 13...Pilot part, 14...Joining stand, 1
5... Carbide chip, 18... Joint surface, 20... Fractured surface, 21... Contact point, 22... Tangent line.

Claims (1)

[Claims for Utility Model Registration] 1. A rotating rotor that rotates around a main shaft provided inside a casing, a plurality of strikers fixed to the outer periphery of the rotating rotor, and a plurality of striking elements arranged around the rotating rotor. A striker for an impact crusher, which is equipped with a repulsion plate provided at a distance, and crushes the raw material splashed by the tip of the rotating striker by colliding with the tip of the striker and the repulsion plate, A piece of carbide material is bonded by heat melting to the tip of the striker or a joining table detachably attached to the tip of the striker, and at least the bonding surface of the outermost piece of carbide material is aligned in the radial direction of the rotating rotor. A striker for an impact crusher characterized by being tilted 3° to 25° in the direction of rotation. 2. A striker for an impact type crusher as set forth in claim 1 of the utility model registration claim, in which a joint stand detachably attached to the striker is divided into a plurality of parts in the axial direction and/or radial direction of a rotating rotor. 3. The striker for an impact crusher as set forth in claim 1 or 2 of the utility model registration claim, in which the width of the cemented carbide material piece in the circumferential direction of the rotating rotor is made wider toward the center of the rotating rotor.