DE10336169B4 - Composite tool for impact and / or abrasive loads - Google Patents

Abstract

The main body (2) is a highly-ductile impact-hardened steel alloy. Cast into it, held by interlocking only, the molding (3) is located in the impact region. It is a prefabricated, solid, highly wear-resistant metal alloy differing from that of the body.

Description

The The invention relates to a composite tool for beating and / or abrasive Charges. Such tools are for example for crushing used by metal, rock or demolition materials. there the tools are extreme loads both in their field directly with the material to be comminuted coming into contact surfaces as also exposed in the area where they are in the respective crusher are held.

From the US 6,216,805 B1 is a drill bit with drill bits known. The drill bits are formed as composite elements of a base body, which consists of an erosion and abrasion resistant material, and an insert inserted into a starting from its opening in the direction of its bottom recess of the base body, which is made of a material which has a higher ductility than the main body. The side of the insert which is exposed during operation to a direct contact with the material to be comminuted in each case is additionally protected by a particularly abrasion-resistant cutting insert. Both the base and the molded body can be made by sintering or hot isostatic pressing and bonded together by press-fitting or other mechanical means. The advantage of the particularly high wear resistance of the base body provided in this prior art is that the area at the circumference of the base body directly below the cutting plate has an extended service life.

simultaneously supports the main body the cutting plate at its periphery. The more ductile material of the insert on the other hand should the impact absorption capacity of the tool as a whole increase. During the Insert from the surrounding body before Wear is protected, damps he largely hits the cutting plate striking blows.

In spite of the above-described mode of action, it is evident in practice that, in the case of drill bits, in the case of drill bits US 6,216,805 B1 described nature or comparable trained tools for the crushing of metal, rock or demolition materials repeatedly comes to breaking the use of the body. This is especially true when the material to be crushed is in large pieces and in the crushing accordingly high kinetic forces must be absorbed by the tools.

Also known from practice and in the DE 28 29 847 A1 are described in use beating and / or abrasive loaded tools that are designed as a so-called "monoblock". Simple embodiments of these block-like tools consisting of a single metal material generally have a uniform hardness over their cross section and their length. On the other hand, monoblock tools better adapted to the loads occurring in each case usually have at least two zones of different hardness, of which the harder is subjected to the direct impact load, while in the region of the tougher, less hard zone the clamping of the tool is carried out in the respective machine ,

One Disadvantage of the above explained simply executed Monoblock tools is that they have a consistently low base hardness or from hacking Materials are made. They usually have too little wear resistance on. In high or differentiated, different over several sections hardened monoblock tools exists against it frequently the risk of breakage in the zones, which has a particularly high hardness and, concomitantly, have a low ductility.

It An attempt has been made to overcome the disadvantages of monobloc tools through tools made of materials with differing mechanical and technological properties to eliminate. The wear-resistant, the high mechanical impact loads receiving moldings are clamped by mechanical aids in the respective body. In practical use, however, it shows that the mechanical connections vulnerable to inter-linked elements fatigue as a result of the high loads occurring during operation.

Also are tools for beating loads that have been generated by composite casting are. In these tools, the wear-resistant molded body in usually by a cohesive Compound held in the material of the body. adversely However, these tools are the high cost of their production, which is characterized by a high expenditure of material and a complex Litigation result. About that In addition, there is a constant risk of breakage of the metal during operation Connection between wear-resistant molded element and basic body. Tools of this type are known for example from DE-PS 592 580.

Finally, composite tools are known in which a sponge-like, porous trained insert, which may consist of metal or a ceramic, is poured into the material of the body. In the course of pouring the penetrates Base material in the opening and cavities of the insert, so that there is an intensive clamping of the body with the inlay. However, a problem with the use of tools produced in this way is that the brittleness of the metal oxides used as the material for the inlay material has a disadvantageous effect on the application behavior of the tools in certain applications.

outgoing from the above-explained state The technique of the invention was the object of a composite tool of the beginning to create the specified type, while minimizing the risk of Tool breakage has a high wear resistance and in the the molded body in Basic body over one long service life is kept safe.

These Task is inventively by a Composite tool for beating and / or abrasive loads have been solved, the one from a highly ductile, final-curing Iron-base alloy produced base body and at least one in the main body cast in, in the main body under the most extensive exclusion of a material connection positively held moldings that is directly exposed in the beating load Area of the composite tool and arranged from one of the iron material of the basic body deviating, highly wear-resistant Metal material as a solid body is prefabricated, wherein the molding is a starting from a footprint in the direction of its base surface opposite face tapering shape owns and whereby the end face the area of the composite tool directly exposed to the impact load assigned.

A such shape is given, for example, when the molding the Basic shape of a truncated pyramid has. In such an im essentially conical from the base to the face tapered shape is easily ensured that the shaped body too is safely held in the body after a long period of operation.

The composite tool according to the invention consists essentially from a basic body, which is produced from a cast, highly ductile material. In the impacting and / or abrasive zone during operation the body is a shaped body placed, which is made of a high-strength, also metallic, preferred iron-based alloy is made. The shape of the molding is chosen so that the shaped body securely held positively in the surrounding material of the body is. At the same time, the materials of the base body and the molded body are the same coordinated, that there is no significant cohesive connection between the molding and the main body comes. Nor is it according to the invention provided that the molding by additional mechanically acting aids is held in the body.

With the invention is a universally applicable in crushing machines, particularly easy to produce composite tool available, the in his the primary Wear exposed Working zone by the molded body arranged there a high wear resistance possesses and at the same time a significantly reduced fragility having. Because the high impact or abrasive loads due to made of hard, wear-resistant Material existing moldings added can, can the material of the main body and the heat treatments applied during its processing without consideration on the loads occurring in practical operation on a preferably high ductility aligned to the body be.

The in the production of composite tools according to the invention applied heat treatment provides that the heat guide during the manufacturing process the necessary parameters for takes into account the two materials to be combined. The goal is to in the main body one possible high ductility and in the molding one possible high hardness to create. This is achieved by a treatment in the high temperature range from 950-1100 ° C. Then done a broken liquid hardening in the Range of 350-600 ° C, to the turn a cool in the air and a subsequent relaxation at temperatures of 300-400 ° C.

One Another significant advantage of the invention is that the molded body in any, more cost effective Way can be prefabricated. So it may be in the case in the composite tool according to the invention cast molded body for example, a forged part, a stamped part, a cut Part, a fired part, a sintered part or a casting act. In this case, the stamped part, fired or cut part of a flat material be prepared.

According to the invention, the selection of the materials used for the base body and the molded body ensures that the specific mechanical-technological properties of both materials, namely on the one hand high-sealing strength for the molding and the other highly ductile for the body, both during the manufacturing process itself and in practical use stay. As for the manufacturer A material which satisfies these requirements is an iron alloy containing (in% by weight) 8.0-22.0% Mn, 0.2-2.8% Cr, 0.5-1, 5% C and the remainder contains Fe and unavoidable impurities. In contrast, an iron alloy which enables a high hardness of the molding contains (in% by weight) 6.0-16.0% Cr, 0.3-1.5 Mo, 0.3-1.4% W, 0.6- 2.2% C and balance Fe and unavoidable impurities. Supported by a heat treatment adapted to the respective material compositions, these alloys can be used to produce particularly durable, robust composite tools which withstand even the toughest loads over the respective required service life. In this case, within the alloy specified according to the invention, the materials of the base body and the shaped body can be matched to one another in such a way that the shaped body is permanently clamped in the composite tool during and as a result of the usage stress.

The Production of a composite tool according to the invention deliberately done so that it does not cause any significant metallic Bond between the molding and the body at least partially surrounding it comes. To the permanent connection between the body and the molding guarantee, is the molding rather, designed so that the molding is positively in Material of the basic body is embedded.

Of the positive Halt the molding can also be achieved in that in the side surfaces of the molding Wells are formed. Alternatively or additionally, for same purpose to the side surfaces of the molding increases be formed.

The invention will be explained in more detail with reference to an exemplary embodiments illustrative drawing. 1 to 4 each show a composite tool in perspective view.

The composite tools shown in the figures 1 . 11 . 21 . 31 each have a cuboid base body 2 on, which is poured from a highly ductile iron material. The main body 2 is starting from its one narrow end face 2a in about a third of the total length L of the body exposed in a practical use the direct contact with the material to be shredded 2 extending working section 2 B , join the work section 2 B subsequent clamping section 2c , on the mounted composite tool 1 . 11 . 21 . 31 the tensioning device, not shown, also attacks a crusher, also not shown, and adjoins the gripping section 2c subsequent storage section 2d divided, where the composite tool 1 is supported in the assembled position in the crushing machine.

When in 1 illustrated composite tool 1 is in the working section of the main body 2 a solid body made of a high-strength, hard iron material 3 cast. The molded body 3 has a hexagonal base 3a with two opposite long sides, which are connected at their ends in each case by two under a blunt, open in the direction of the inner surface open angle meeting each other short sides. Starting from the shaped base 3a the shaped body tapers 3 in the direction of the front side 2a of the basic body 2 ,

In this way, one is starting from the base 3a in the direction of the front side 2a of the basic body 2 associated end face 3b of the molding 3 tapered shape of the molding 3 educated. The shaped body shaped in this way 3 is in new condition of the composite tool 1 laterally and in the area of its base 3a from the material of the basic body 2 completely surrounded. The middle one, in a parallel to the front side 2a towards the wider side surfaces of the body 2 extending and perpendicular to this aligned measuring axis X measured wall thickness d _G1 of the shaped body 3 in the thickness direction laterally surrounding wall 2f of the basic body 2 is chosen so that the ratio of the average wall thickness d _G1 to measured in the same measuring axis X average thickness d _{F1 of} the molding 3 is about 0.3. In a corresponding manner, the thickness d _G2 measured in a measuring axis Y oriented transversely to the measuring axis X is the shaped body 3 in the width direction laterally surrounding wall 2e of the basic body 2 chosen such that the ratio of the average wall thickness d _G2 to measured in the same measuring axis Y average thickness d _{F2 of} the molding 3 is about 0.2.

By this dimensioning of the formed body 3 laterally surrounding walls 2e . 2f of the basic body 2 in combination with the conical face towards his face 3b tapered shape of the molding 3 is ensured that the molding 3 even under high impact loads occurring in practice safely in the composite tool 1 is held. The coordination of the materials of shaped bodies supports this 3 and basic body 2 not only the firm hold of the molding 3 in the main body 2 But above all, it ensures that the risk of breakage of the composite tool 1 in the region of the clamping section 2c or the storage section 2d is reduced to a minimum.

In the working section 2 B of the basic body 2 of in 2 illustrated composite tool 11 is also a solid made of a high-hardness iron material molded body 13 cast. Unlike the composite tool 1 surrounds the material of the body 2 the shaped body 3 in new condition of the composite tool 11 Completely.

Again, according to the in 1 Shaped body 3 , indicates the shaped body 13 of the composite tool 11 one starting from its base 13a in the direction of its the front 2a of the basic body 2 associated end face 13b rejuvenating shape. The base area 13a and accordingly the face 13b of the molding 13 are also hexagonal, with the surfaces 13a . 13b are limited in this case by two short, mutually parallel opposite sides, which blunt by two in each case, to the respective surface 13a . 13b open angle to each other on longer sides are connected.

Also with the composite tool 11 is so by the essentially conical, starting from the base 13a Rejuvenating, shaping of the massive molding 13 and the embedding of the molding 13 in the material of the body 12 ensured that the molding 13 Even after a long period of operation still safe in the body 2 held and capable of working on the composite tool 11 to pick up directly striking beating load just as safely.

When in 3 shown composite tool 21 is in the working section 2 B of the basic body 2 in turn, a solid formed from a hard metal material, solid molded body 23 cast. Like the composite tool 11 surrounds the material of the body 2 the shaped body 23 completely new when new.

The molded body 23 has a truncated pyramidal, four side surfaces 23c . 23d . 23e . 23f having basic form, whose base area 23a bigger than its the front 2a of the basic body 2 assigned end face 23b , In two of the opposite side surfaces 23c . 23d of the molding 23 are arranged at regular intervals, extending the length of the molding 23 extending channel-like depressions 23g molded while on the other two opposite side surfaces 23e . 23f in irregular arrangement knob-like projections 23h are formed. The wells 23g and the projections 23h support in combination with the conical starting from the base 23a in the direction of the face 23b tapered shape of the molding 23 its secure, positive fit in the material of the body 2 , The composition of the iron material of the basic body 2 is tuned to the composition of the iron material, from which the molding 23 is made that the molding 23 after the completion of the composite tool 21 due to the different thermal expansion behavior of both materials in addition in the body 2 is held force-fit under tension.

When in 4 illustrated composite tool 31 Finally, three are each made of a wear-resistant, hard iron material as a solid body moldings 33 ' . 33 '' and 33 ''' cast. The moldings 33 ' . 33 '' . 33 ''' are each truncated pyramid-shaped and run starting from their rectangular base 33a in the direction of the front side 2a of the basic body 2 of the composite tool 31 assigned and in new condition flush with this aligned face 33b conical too. The length of between the two outer moldings 33 ' . 33 ''' arranged shaped body 33 '' is about half the size of the other two moldings 33 ' and 33 ''' , The moldings 33 ' . 33 '' and 33 ''' are arranged at a distance that both the ratio of measured in the direction of the measuring axis X mean wall thickness d _G1 of the moldings 33 ' . 33 '' and 33 ''' each surrounding material in the thickness direction of the body 2 for measured in the same measuring axis X average thickness d _{F1 of} the moldings 33 ' . 33 '' . 33 ''' as well as the ratio of measured in the direction of the measuring axis Y mean wall thickness d _G2 of the molded body 33 ' . 33 '' and 33 ''' each surrounding material in the width direction of the body 2 for measured in the same measuring axis Y average thickness d _{F2 of} the molded body 33 ' . 33 '' . 33 ''' in the range of 0.2 to 1.0. As already related to the in 1 illustrated composite tool 1 is explained by this to the average thickness d _F1 , d _{F2 of} the molding 33 ' . 33 '' . 33 ''' related vote of the wall thicknesses d _G1 or d _G2 ensured that even under the hard loads occurring in practical use of the molding 33 ' . 33 '' . 33 ''' in a ductile iron material of the basic body which is sufficiently elastic for a permanently secure hold 2 in the composite tool 31 are held.

An important advantage of in 4 illustrated composite tool 31 is that with the introduction of several harder moldings 33 ' . 33 '' . 33 ''' into the highly ductile basic body 2 through the between the individual moldings 33 ' . 33 '' . 33 ''' existing ductile base material, the risk of breakage in practical use is substantially minimized. The different length of the moldings 33 ' . 33 '' . 33 ''' takes into account the limitation of the desired increased wear resistance on zones of the main wear spruchung.

1, 11, 21, 31

Composite Tools

2

body

2a

narrow Front side of the main body

2

2 B

Working section of the basic body 2

2c

Clamping section of the body 2

2d

Bearing section of the body 2

3, 13, 23, 33 ', 33' ', 33' ''

moldings

3a, 13a, 33a

Footprint of the respective

molding 3 . 13 . 23 . 33 ' . 33 '' . 33 '''

3b, 13b, 33b

Face of the respective

molding 3 . 13

2e

walls 2e of the basic body 2

23c, 23d, 23e, 23f

Side surfaces of the molding 23

23g

channel-like wells

23h

projections

d _G1 , d _G2

middle Wall thickness the one

moldings 3 laterally surrounding

wall 2e

d _F1 , d _F2

average thickness d _{F1 of} the molding 3

L

Total length of the main body 2

X, Y

measuring axes

Claims (11)

Composite tool ( 1 . 11 . 21 . 31 ) for impacting and / or abrasive loads with a base body produced from a highly ductile, hail-hardening iron-based alloy ( 2 ) and at least one in the main body ( 2 ), in the basic body ( 2 ) under largely exclusion of a cohesive connection positively held moldings ( 3 . 13 . 23 . 33 ' . 33 '' . 33 ''' ), the area of the composite tool directly exposed to the impact load ( 1 . 11 . 21 . 31 ) and from one of the iron material of the basic body ( 2 ) deviating, highly wear-resistant metal material is prefabricated as a solid body, wherein the molded body ( 3 . 13 . 23 . 33 ' . 33 '' . 33 ''' ) one starting from a base surface ( 3a . 13a . 33a ) in the direction of its base surface ( 3a . 13a . 33a ) opposite end face ( 3b . 13b . 33b ) has a tapered shape and wherein the end face ( 3b . 13b . 33b ) the area directly exposed to the beating load ( 2a ) of the composite tool ( 1 . 11 . 21 . 31 ) assigned. Composite tool according to claim 1, characterized in that the shaped body ( 3 . 13 . 23 . 33 ' . 33 '' . 33 ''' ) is a forging. Composite tool according to claim 1, characterized in that the shaped body ( 3 . 13 . 23 . 33 ' . 33 '' . 33 ''' ) is a stamped part. Composite tool according to claim 1, characterized in that the shaped body ( 3 . 13 . 23 . 33 ' . 33 '' . 33 ''' ) is a cut part. Composite tool according to claim 1, characterized in that the shaped body ( 3 . 13 . 23 . 33 ' . 33 '' . 33 ''' ) is a burned part. Composite tool according to one of claims 3 to 5, characterized in that the shaped body ( 3 . 13 . 23 . 33 ' . 33 '' . 33 ''' ) is made of a flat material. Composite tool according to claim 1, characterized in that the shaped body ( 3 . 13 . 23 . 33 ' . 33 '' . 33 ''' ) is generated by sintering. Composite tool according to claim 1, characterized in that the shaped body ( 3 . 13 . 23 . 33 ' . 33 '' . 33 ''' ) is a casting. Composite tool according to one of claims 1 to 8, characterized in that the iron alloy of the base body ( 2 ) (in weight%) Mn: 8.0-22.0%, Cr: 0.2-2.8%, C: 0, 5-1, 5, and balance Fe and unavoidable impurities. Composite tool according to one of claims 1 to 9, characterized in that the metal material of the shaped body ( 3 . 13 . 23 . 33 ' . 33 '' . 33 ''' (in% by weight) Cr: 6.0-16.0 Mo: 0.3-1.5 W: 0.3-1.4 C: 0.6-2.2 and balance Fe and unavoidable Contains impurities. Composite tool according to one of the preceding claims, characterized in that the shaped body ( 3 . 13 . 23 . 33 ' . 33 '' . 33 ''' ) has the shape of a truncated pyramid.