DE102007007276A1 - Armoring of the surfaces of roller press rolls - Google Patents

Abstract

In order to provide for the surfaces of roller presses for the pressure treatment in particular Gutbettzerkleinerung granular material armor, which can overcome previous limits in terms of wear resistance, durability and height of usable roller press, the invention proposes to use as a material of the roll shell (10) ADI, a Kugelgraphitguss with bainitic structure, further mold in the surface of the roll shell (10) spaced recesses for autogenous wear protection and in each of the roll shell end faces located recesses (13) radially and axially projecting fixed hard body (12) to use, which is a squeezing out the Gutmaterials prevent beyond the roll shell end faces and form a roll armor on the roll edges with autogenous wear protection.

Description

The The invention relates to armoring of the surfaces of roller press rolls for pressure treatment, in particular fine bed crushing granular material.

at Roll mills become granular brittle material in the nip, through which the two rotatably mounted counter-rotating rotatable rollers are separated from each other, fed and there one Subjected to crushing. Also known is the so-called Gutbettzerkleinerung in the nip of a high-pressure roll mill, Also called roller press, in which the individual particles of Friction in the nip drawn good material in a good bed, d. H. in a compressed between the two roll surfaces Bulk material when using a high pressure each other be crushed. The roller surfaces are one exposed to high compressive stress and wear stress.

In the DE 10 2004 043 562 A1 thick-walled annular bandages have been proposed for the press rolls of such roller presses as a roll shell whose material consists of a heat-treated spheroidal graphite cast iron with bainitic structure with retained austenite, such a material often being designated by the term ADI (Austempered Ductile Iron) ( Foundry practice No. 7/8 - 1997, page 152 ). Such a material is characterized by the fact that the casting material in the Randschich th of the bandages cures by external pressure loading of the drum surface. It is also known to einzuformen in the outer surface of such ring bandages spaced recesses into which to be treated during operation of the roller press Gutmaterial which is to remain there during the roller revolutions form an autogenous wear protection for the drum surfaces and also have a good intake behavior due to its roughness should. However, the risk is not excluded that pressed in the roller press operation in the nip pressed material in an undesirable manner beyond the Walzenmantelstirnseiten out.

Farther it is known to armor the roll edges, that a peripheral groove is arranged in the region of the peripheral edge edges of the roll, which is filled with hardfacing material.

Further, it is from the booklet 2-201d "Mahlanlagen von KHD Humboldt Wedag", 7/2000, pages 18 and 19 known to realize the above autogenous wear protection on the roller surfaces of roller presses characterized in that on the roller surface a variety of prefabricated hard bodies such. B. powder-metallurgically produced knob bolt is disposed, which are embedded in corresponding holes of the roll shell, said anti-wear technology is called grid armor. In this case, the stud bolts protrude with such a large amount outward from the roller surface and they are spaced apart such that during operation of the roller press the spaces between the stud bolts are filled with the compressed fine-grained material for the purpose of bringing about the autogenous wear protection. This type of armoring of the surfaces of roller press rolls has proven itself in the case of comminuted bedding, in particular of ore material in practice. However, care must be taken to ensure that cracks in the roll shell, in particular at the base of the stud bolt bores, do not occur during operation due to the load on the stud bolts.

Of the Invention is the object of the surfaces of roller press rollers for pressure treatment in particular Gutbettzerkleinerung granular Gutmateriales an armor to create in terms of life time and height the usable roller press pressure and wear resistance overcome previous boundaries.

These Task is according to the invention with an armor solved with the features of claim 1. advantageous Embodiments of the invention are in the subclaims specified.

at the press roll armor according to the invention consists the material of the roll jacket made of ADI (Austempered Ductile Iron). This material has a high elongation at break, compressive strength and Toughness. Surprisingly, it has been shown that This high-alloyed material can work well with tools leaves, so that incorporated recesses such. B. holes can be drilled for the use of z. B. pin-shaped Hard bodies to enable the above described autogenous wear protection. In addition, has become shown that this material due to its Kugelgraphitgussgefüges possibly occurring microcracks brings to a stop and a high Rissunempfindlichkeit so that the risk of cracking of the roll shell starting especially from the bottom of the hole or groove bottom is minimized. On the contrary: the basic material ADI forms the roller press during operation when stressed by pressure hardening hard surface layers, which are capable of the hard body used in recesses such as holes how to hold peg bolts free of play and a roll shell wear through otherwise occurring micro-movements of the hard body not at all to let occur.

Because in the surface armor according to the invention even when using hard bodies, the risk of cracking minimized in the roll shell, can significantly higher Pressing pressures in the nip of the roller press for implementation energy-saving bedding comminution are applied, wherein then, however, the inclination increases that part of the autogenous Wear protection material as well as between the press rollers pressed material in an undesirable manner over the roll shell end faces can be pushed out. Around To prevent this, at least on the roll shell end faces Fixed at the edges of hard body, the radial and protrude axially from the roll shell and on the one hand a dam for the pressed material and on the other hand a wear protection for forming the roll shell end faces.

Would In contrast, in a roll shell of the material ADI on the annular roll edges circumferential peripheral welding beads weld on as weld layer edge bead rings, Stress cracks would be created that arise when welded on an unprofiled ADI material surface becomes.

Of the Roller press pressure can according to the invention clearly be increased without risk of running in the roll shell Cracks arise. By the possible increased Pressing with the use of hard bodies is in the Intermediate pressed Well held even safer for autogenous wear protection even at relatively brittle to be subjected to the Gutbettzerkleinerung Good materials such. B. slag.

at the press roll armor according to the invention can the spaced-apart recesses formed in the roll shell along Rolling sheath lines be running through grooves, which at their two located on the roll shell end faces by one each fixed hard body are completed. To this end But also at the roll edges ring segments be arranged, which releasably secured to the roll end face are, in which case several such ring segments each to a circular ring are composed, for. B. 8 pieces 45 ° ring segments or z. B. 12 pieces 30 ° ring segments.

Around the risk of cracking in the inventive Press roll armor can still further minimize the radially inner ends of the cylindrical or polygonal produced by powder metallurgy Hard body and the corresponding roll shell recesses or holes in their deepest area curved outward Surfaces, almost the curved shape a Halbkugelkalotte to notch stresses in the roll shell not to let arise at all.

The Invention and its other features and advantages are based the embodiments schematically illustrated in the figures explained in more detail.

It shows:

1 3 shows a perspective view of a section of a region of a thick-walled annular bandage located on the right-hand side as a roll shell of a roller press press roll for comminuted granular material with a first embodiment of a surface armor,

2 : the armor of the 1 before the hard bodies fixable on the roll shell end faces have been inserted,

3 : the armor of the 1 and 2 with application of additional welding armor,

4 : the roll armor of the 3 with edge hard bodies of a slightly different configuration,

5 : partial view of the front of an armored roll mantle with edge hard bodies as in 1 and with nubbolt bolts arranged in bores distributed over the entire roll surface as a grid armor,

6 - 8th : again in perspective as further embodiments press roller armor whose armor at the roll edges are composed by profiled and hard-welded ring segments.

In the roll armor of 1 As well as the other figures, the material of the cast as a thick-walled ring bandage roll shell 10 made of ADI, a material that is easy to machine and that is characterized by high resistance to cracking. As well as in 2 clearly visible, are in the roll shell 10 spaced along roller mills lines, so axially extending through passage grooves 11 molded or incorporated, which at its two ends located on the roll shell end faces by a respective fixable powder metallurgically produced hard body 12 are completed, with the hard body at 2 left out but at the 1 and 3 already used. These hard bodies 12 are in radial recesses 13 of the roll mantle 10 inserted such that they protrude at least radially from the roll surface and possibly also axially from the roll shell end face.

The distributed around the circumference of the Walzenmantelstirnseiten hard body 12 each have a cylindrical part 14 on, in the radial recesses 13 of the roll mantle 10 is fitted, causing the hard body 12 in the roll jacket 10 axially secured, while they are secured radially in particular by gluing. The attached to the cylindrical part 14 the edge hard body 12 outwardly adjoining part has a rectangular format in cross section.

In operation of the roller press are the groove-shaped recesses 11 filled with compressed fine-grained Gutmaterial that forms an autogenous wear protection. The at the roll shell end faces in the radial recesses 13 inserted protruding edge hard body 12 prevent pressing out of the autogenous wear protection material and pressed in the nip in the Gutbettzerkleinerung good material on the roll shell end faces out, and also serve these edge hard body 12 for wear protection of the two roll shell end faces.

Out 3 shows that the between the spaced grooves 11 lying Profilierungsvorsprünge the roll shell surface still consisting of hard aggregate hardfacing beads 15 can be armored. This additional welding armor creates no problems, since the welding stresses generated during buildup welding are almost completely reduced by the web-shaped profiling protrusions and the risk of cracking due to bottom cracks in the roll shell is avoided.

The edge-hard body 12a of the 4 differ from those of 1 to 3 in that on the cylindrical part 14 of the edge hard body 12a inward still a footbridge 16 is formed, with these webs 16 from the Nutenden ago in the Durchgangsnuten 11 extend and complicate a Walzstirnseitiges pressing out of Gutmaterial. In this embodiment, the risk of welding the edge hard body 12a through the surfacing worms 15 minimized.

The front view of the 5 leaves the over the circumference of the roll mantle 10 on the roll shell end side distributed edge hard body 12 respectively. 12a recognize as well as a variety of distributed over the entire roll surface in holes arranged stud bolts 17 as a grid armor for the autogenous wear protection, this grid armor can be arranged both on an unprofiled roll shell without the use of axial through grooves and on a profiled roll shell. To the risk of cracking in the roll shell 10 To further reduce, have the radially inner ends 18 the cylindrical stud bolt 17 and the corresponding holes in their deepest area approximately the curved shape of a hemispherical calotte. In operation of the roller press are the spaces between all protruding hard bodies 17 and 12 filled with compressed fine-grained material for autogenous wear protection.

According to embodiments of the 6 to 8th the press roll armor is not formed at the roll edges by distributed around the circumference single edge hard body, but by special ring segments which are releasably secured to the roll end face, wherein a plurality of such ring segments are each assembled into a circular ring. In 7 is a single roll edge ring segment 19 drawn out, which extends over a circular arc of 45 °. 8 pieces of such ring segments 19 can be assembled into a circular ring. But it can also z. B. 12 pieces of such ring segments with a circular arc of 30 ° to be composed of a closed circular ring. In any case, it can be clearly seen that the ring segments 19 in cross section, an approximately U-shaped inwardly angled nose 20 with whom they like, like 6 can be seen in a lying in the vicinity of the roll shell end circumferential circumferential groove 21 of the roll mantle 10 are hung. Through the nose 20 with their connector are the ring segments 19 secured axially, while the radial securing is made by bolts passing through corresponding holes 22 . 23 etc. of the ring segments 19 through into the roll jacket 10 be introduced.

The material of the edge ring segments 19 can be made of steel or cast steel, which may still have a wear protection layer on its outer surface. The assembly / disassembly of the pressure roller edge armor produced in this way is very simplified according to the invention.

In any case, serve the ring segments to the operation of the roller press in the grooves 11 einzhresste Gutmaterial einbirnseitig and to prevent pushing out of the pressed Gutmaterials axially beyond the side edges of the press rollers out. The to the ring segments 19 molded axially extending short webs 24 . 25 etc. close the passage grooves 11 of the 6 Safe at both ends.

Also in the embodiment of 6 can as with 3 demonstrates that between the spaced grooves 11 lying Profilierungsvorsprünge the roll shell surface still consisting of hard aggregate hardfacing beads 15 then being armored with respect to their exterior circumferentially in a height with the outer periphery of the edge ring segments 19 lie.

One to the edge ring segment 19 of the 7 similar edge ring segment shows 8th , whose approximately U-shaped inwardly angled nose 20a has a slightly different configuration. Anyway, both on 7 as well 8th to recognize that the outsides of the angled noses 20 . 20a the ring segments spaced Nuteinbuchtungen 26 . 27 which have the grooves extending along generatrices in the roll shell surface 11 Limit at both longitudinal ends.

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• DE 102004043562 A1 [0003]

Cited non-patent literature

• - Foundry practice no. 7/8 - 1997, page 152 [0003]
• - "Mahlanlagen von KHD Humboldt Wedag", 7/2000, pages 18 and 19 [0005]

Claims (10)

Armoring of the surfaces of roller press rolls for pressure treatment, in particular fine bed crushing of granular material, characterized by the following features: a) the material of the roll shell ( 10 ) consists of ADI (Austempered Ductile Iron), a nodular cast iron with bainitic structure; b) into the surface of the roll mantle ( 10 ) are formed spaced apart recesses for autogenous wear protection; c) in the respectively located on the roll shell end faces recesses ( 13 ) are radially and axially projecting fixed hard body ( 12 respectively. 12a ), which prevent the material from being pressed out beyond the roll shell end faces and form a roll armor at the roll edges with autogenous wear protection. An armor according to claim 1, characterized in that the hard bodies distributed around the circumference of the roll shell end faces ( 12 respectively. 12a ) each have a cylindrical part ( 14 ), which in the radial recesses ( 13 ) of the roll mantle ( 10 ) is fitted, wherein the hard body ( 12 respectively. 12a ) in the roll shell ( 10 ) are caught axially and secured radially by gluing. An armor according to claim 1, characterized in that in the roll shell ( 10 ) formed spaced apart recesses along roll generating lines extending through grooves ( 11 ), which are at their two ends located on the roll shell end faces by a respective fixed hard body ( 12 respectively. 12a ) Are completed. An armor according to claim 3, characterized in that between the spaced grooves ( 11 ) Profilierungsvorsprünge the roll shell surface still made of hard materials build-up welding beads ( 15 ) are armored. Armor according to claim 1, characterized in that the roll armor at the roll edges by ring segments ( 19 ) is formed, which are releasably secured to the roller end face, wherein a plurality of ring segments are each assembled into a circular ring. Armor according to claim 5, characterized in that the ring segments ( 19 ) seen in cross-section an approximately U-shaped inwardly angled nose ( 20 . 20a ), with which they in a lying in the vicinity of the roll shell end face peripheral circumferential groove ( 21 ) of the roll mantle ( 10 ) are mounted. Armor according to claim 6, characterized in that the outsides of the angled noses ( 20 . 20a ) of the ring segments spaced Nuteinbuchtungen ( 26 . 27 ), which extend along the roll surface lines in the roll shell surface grooves ( 11 ) at both longitudinal ends. Armor in particular according to claim 1, characterized in that in the radial recesses distributed over the entire roll surface on the roll shell surface outwardly projecting hard body ( 17 . 12 respectively. 12a ) are used, wherein in the operation of the roller press the spaces between all the above hard bodies are filled with compressed fine-grained material for autogenous wear protection. Armor according to claim 1 or 8, characterized in that the hard bodies ( 12 respectively. 12a . 17 ) powder-metallurgically produced and are cylindrical or polygonal. An armor according to claims 8 and 9, characterized in that the radially inner ends ( 18 ) the hard body ( 17 ) and the roll shell recesses in their lowest area outwardly curved surfaces, approximately the curved shape of a Halbkugelkalotte.