A wear-resistant and long-life high-pressure roller sleeve for crushing sintered pellet ore powder

Abstract

The present invention is applicable to the technical field of mineral powder crushing, and provides a wear-resistant and long-life high-pressure roller sleeve for crushing sintered pellet mineral powder, wherein the outer surface of the roller sleeve is surrounded by carbide studs and inlaid with wear-resistant studs; the carbide studs in the non-roller surface middle area of ​​the roller sleeve are sintered by a WC cobalt-based alloy containing 5-10% by volume of nano-grade WC or / and TⅰC and an appropriate amount of rare earth yttrium or / and cerium; the wear resistance of the carbide studs in the roller surface of the roller sleeve is lower than that in the middle area, or the protruding height is 1-3mm lower than that in the middle area; the two end surfaces of the roller sleeve are surfacing-welded with a nickel-chromium-boron-silicon-based alloy containing more than 60% WC; the roller sleeve and the roller shaft are assembled by interference fit of multi-step stepped shaft holes. The present invention can greatly reduce the wear amount of carbide in the length direction under unit crushing amount, maintain the flatness of roller surface studs for a long time, maintain the stability of the protruding length of studs, have the ability to resist the formation of deep pits on the roller surface due to the entry of foreign matter and prevent the collapse of the edge of the roller sleeve, and facilitate the replacement and installation of the roller sleeve.

Description

Technical Field

[0001] The invention relates to the technical field of mineral powder crushing, in particular to a wear-resistant and long-life high-pressure roller sleeve for crushing sintered pellet mineral powder. Background Art

[0002] Pelletized ore is an important raw material for steel smelting. It has high iron grade, good strength and excellent metallurgical properties. The energy consumption and carbon emissions of the pelletized ore production process are only 50% and 65% of those of the sintered ore production process. It is a high-quality low-carbon raw material for steel smelting.

[0003] In the iron ore pelletizing industry, high pressure roller mill has the characteristics of high crushing efficiency, low energy consumption, good wear resistance, and can handle materials with high water content. It is used in large-scale pelletizing plants to improve the balling of materials, reduce the proportion of bentonite, improve the roasting performance of pellets and the metallurgical properties of finished pellets, and reduce production costs. The high pressure roller adopts the principle of lamination crushing. The material is enclosed in the extrusion roller and the feeding device, and is crushed by static pressure. It will not produce a large impact and splash of the material, making the vibration and noise low; at the same time, the particles in the material layer are displaced, compacted, and micro-cracks and crushing occur, which improves the activity of the material and is conducive to the subsequent pelletizing.

[0004] The working parts of the high pressure roller mill are a pair of high pressure rollers arranged in parallel and rotating in opposite directions, including fixed rollers and movable rollers. In industrial production, the main rollers used are spiked rollers, such as Figure 1 shown.

[0005] Since there is less material on the sides of the roller surface than in the middle during feeding, in order to reduce the difference in wear between the middle and side studs, Figure 2 As shown, the prior art designs the wear resistance of the two side column nails (within about 60-100mm width) to be lower than that of the middle column nail. In the prior art, the wear resistance of the middle column nail has not been greatly improved. The wear resistance of the carbide side column nails is too low and it is difficult to withstand high pressure conditions. When the middle column nail is worn to a certain length, Figure 3 As shown, generally when the wear reaches 15mm, the height difference between the wear in the middle and the sides reaches 10mm, forming an axial concave with high sides and low middle.

[0006] The thickness of the pellet layer is generally controlled at 26-30mm, which can meet the material pressing effect and the material passing requirement. When the new roller is installed for the initial use, the gap between the two roller pins is generally adjusted to 14-16mm. During operation, the ore material will pressurize the two rollers to 18-20mm. At this time, the two roller pins are extended 4-5mm each, and the material layer thickness is 26-30mm. When the pins are worn during use, the gap between the two rollers is adjusted to be smaller. When the roller surface is worn to 10mm or more inwardly concave in the axial direction, when the gap between the two roller pins is adjusted to 20mm, the pins on both sides will also push against each other, and they will be forced to release, which will make the material layer thicker and fail to achieve the roller crushing effect.

[0007] The micro-movement of the high-pressure roller during the lamination of mineral materials will also cause certain wear on the roller surface. The best effect is that the wear rate of the roller surface is consistent with the wear rate of the studs. In the prior art, the actual wear of the roller surface is faster than the wear of the studs, which causes the studs to protrude longer. The longer the studs protrude, the thicker the material layer will be when the gap between the two rollers is the same. That is, the sum of the lengthened dimension of the stud protrusion and the inner concavity dimension shall not be greater than 10mm. Therefore, the roller sleeve of the high-pressure roller in the prior art is made of 33NiCrMoV14-5 (German standard) material. The material has excellent comprehensive performance, but it still cannot meet the demand for synchronization with the existing stud wear rate. When the inner concavity is about 6mm, the protruding length of the stud increases by about 2mm. At the same time, because the material itself is relatively hard, it brings great difficulty to the precise processing of the column nail installation holes. For this reason, this type of products has changed the precise interference fit installation of the column nail and the hole to the column nail and hole gluing process. This process cancels the original state of the column nail being subjected to pre-pressure to reduce alternating stress, making the column nail more prone to fatigue peeling failure. The column nail extends outward and is also more likely to break and fragment when foreign objects enter.

[0008] In the crushing operation of pelletized ore, deep pits often appear on the roller surface of the existing high-pressure roller. Analysis shows that iron block foreign matter has entered during the operation, and the column nails used have been hardened and broken. After the roller surface loses its protection, the base body wears, causing the surrounding column nails to fall off, thus forming local deep pits. The deep pits on the roller surface allow a large amount of ore to pass directly without being rolled, seriously affecting the quality of ore processing.

[0009] like Figure 4 As shown in the figure, both end faces of the existing high-pressure roller sleeve are generally equipped with high-quality CrC series wear-resistant lining plates, such as Vautⅰd-100 6+4 wear-resistant plates, but their wear resistance is still relatively low and they need to be replaced regularly during use, which increases the maintenance intensity. They are often out of repair due to insufficient maintenance time, resulting in excessive wear on the ends, causing the studs on the edge of the roller surface to fall off and causing local edge collapse.

[0010] like Figure 5 As shown, in the existing high-pressure roller, the roller sleeve is mounted on the roller shaft, and the roller sleeve is relatively thick, which makes forging and processing difficult.

[0011] The crushing effect of the high-pressure roller is very important, which is directly related to the amount of bentonite added when preparing the pellets. Solving the current problems of crushing pellets with high-pressure rollers is of great significance for pellet production and even subsequent ironmaking production. Summary of the invention

[0012] The object of the present invention is to provide a wear-resistant and long-life high-pressure roller sleeve for crushing sintered pellet ore powder, so as to solve the problems in the above-mentioned background technology.

[0013] To achieve the above object, the present invention provides the following technical solution: a wear-resistant and long-life high-pressure roller sleeve for crushing sintered pellet ore powder, wherein the outer surface of the roller sleeve is surrounded by hard alloy studs and is inlaid with wear-resistant studs;

[0014] The hard alloy studs in the middle area of ​​the roller surface of the roller sleeve are sintered from a WC cobalt-based alloy containing 5-10% by volume of nano-grade WC or / and TIC and an appropriate amount of rare earth yttrium or / and cerium;

[0015] The wear resistance of the carbide studs on the sides of the roller surface of the roller sleeve is lower than that in the middle, or the protruding height is 1-3mm lower than that in the middle;

[0016] The roller sleeve has two end surfaces built up with nickel-chromium-boron-silicon based alloy containing more than 60% WC;

[0017] The roller sleeve and the roller shaft are assembled by interference fit through multi-step shaft holes.

[0018] Preferably, the wear-resistant nail is made of high-speed steel or hard alloy, with a diameter of 5-8 mm and a length of 8-15 mm, and the end of the wear-resistant nail is flush with the surface of the roller sleeve;

[0019] The WC cobalt-based alloy of the cemented carbide studs in the middle area of ​​the roller surface of the roller sleeve further contains 2-3% by volume of Cr and / or 2-5% by volume of NbC;

[0020] The flexural strength of the cemented carbide stud is greater than 3500 MPa, the diameter is 16-18 mm, the stud head is spherical or conical, and the stud length is 20-35 mm;

[0021] The roller sleeve body is drilled with a hole, and the stud is pressed into the hole with an interference fit of 0.04 to 0.06 mm, and the extension length is 4 to 5 mm;

[0022] The two end surfaces of the roller sleeve are clad with nickel-chromium alloy containing more than 60% WC, the cladding ring width at both ends is 100-120mm, the thickness is 5-10mm, the roller cover edge, the cladding width is 10mm, the thickness is 4-5mm;

[0023] The roller sleeve and the roller shaft are assembled by interference fit of multi-step shaft holes. The roller sleeve is made of 42CrMo, has a thickness of 100-120mm, 3-4 steps, and a step diameter difference of 5-10mm. After interference fit, both ends are welded and reinforced.

[0024] Preferably, the particle size of nano-scale WC and / or TIC is 50-100 nm, and the other component particles are ball-milled together with the 3um WC particles. When the 3um WC particles are ball-milled to 1.4-1.6um, the powders are sintered to make the cemented carbide studs in the middle area of ​​the roller surface.

[0025] Preferably, when the high-pressure roller is running in the same operation control standard longevity mode, the length of the carbide ball head stud in the middle area of ​​the roller surface is 35 mm, the length of the conical head stud is 30 mm, the allowable wear length is 20 mm, and the axial concavity of the roller surface stud is allowed to be 4 to 6 mm;

[0026] When the high-pressure roller is running in the same life cycle high operation control standard mode, the length of the carbide spherical head studs in the middle area of ​​the roller surface is 25mm, the length of the conical head studs is 20mm, the allowable wear length is 10mm, and the axial concavity of the roller surface studs is allowed to be 2-3mm.

[0027] The present invention has at least the following beneficial effects:

[0028] The wear-resistant and long-life high-pressure roller sleeve for crushing sintered pellet ore powder provided by the present invention can greatly reduce the wear amount of cemented carbide in the length direction under unit crushing amount, maintain the flatness of the roller surface column nails for a long time, maintain the stability of the extended length of the column nails, resist the formation of deep pits on the roller surface due to the entry of foreign matter and prevent the edge of the roller sleeve from collapsing, and facilitate the replacement and installation of the roller sleeve. The use of the present invention can greatly increase the service life and achieve continuous and efficient crushing effect during use. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a schematic diagram of a double roller;

[0030] Figure 2 Schematic diagram of different column nail materials;

[0031] Figure 3 It is a schematic diagram of the high, medium and low structure of the column nail side;

[0032] Figure 4 It is a schematic diagram of the wear-resistant lining structure;

[0033] Figure 5 It is a schematic diagram of the thick roller sleeve structure;

[0034] Figure 6 This is a schematic diagram of the structure of a thick roller sleeve with nails;

[0035] Figure 7 This is a schematic diagram of the column nail side low middle high structure;

[0036] Figure 8 This is a schematic diagram of the step matching structure;

[0037] Fig. 9 It is a schematic diagram of the preferred wear-resistant nail;

[0038] Fig.10 It is a schematic diagram of the optimal selection of column nails;

[0039] Fig.11 It is a schematic diagram of the protrusion of the column nail;

[0040] Fig.12 This is a schematic diagram of surfacing welding;

[0041] Fig.13 This is a schematic diagram of the optimal step coordination. DETAILED DESCRIPTION

[0042] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0043] Aiming at the problems existing in the existing technology, the causes of the problems are analyzed and effective system solutions are proposed. The fundamental reason for the concavity of the roller surface studs is that the wear resistance of the middle studs of the roller surface is insufficient, and the wear resistance of the hard alloy studs on the edge of the roller surface that can withstand high pressure cannot be pulled apart in a similar proportion to the amount of material passing, so that when the wear of the middle studs is 15mm, the concavity reaches 10mm. The main reason for the insufficient wear resistance of the middle studs is fatigue spalling failure, as analyzed from the wear failure morphology.

[0044] The main measure adopted by the present invention is to strengthen the Co base by adding 5-10% by volume of nano WC or / and TⅰC and an appropriate amount of rare earth yttrium (Y) or / and cerium (Ce), and to add 2-3% of Cr to enhance the toughness between Co and WC, or / and 2-5% of NbC to further improve its pure wear resistance, thereby increasing its flexural strength to more than 3500MPa. The current diameter is generally 16mm, preferably 16-18mm. When the working conditions are worse, 18mm diameter studs can be partially or completely used. The stud heads are still spherical or conical, and the stud length is preferably 20-35mm. In order to better combine the ingredients, the mixture is ball-milled and the raw material particles are spheroidized. Preferably, the cemented carbide studs in the middle area of ​​the roller surface are sintered by a WC cobalt-based alloy containing 5-10% by volume of nano-scale WC or / and TI C and an appropriate amount of rare earth yttrium (Y) or / and cerium (Ce). The particle size of the nano-scale WC or / and TI C is preferably 50-100nm. Other components such as Cr, Y, Ce, and NbC particles are ball-milled together with WC particles preferably of 3um. When the 3um WC particles are ball-milled to 1.4-1.6um, the powder is sintered to make the cemented carbide studs in the middle area of ​​the roller surface.

[0045] The present invention still adopts the method of drilling holes on the roller sleeve body, and the column nails are hot-fitted and pressed into the holes with an interference fit of 0.04 to 0.06 mm, and the overhang length is 4 to 5 mm. Compared with the gluing process, the interference fit method pre-adds compressive stress to the column nails, so that when the column nails are subjected to alternating stress once per rotation of the pressing material, the alternating stress difference is greatly reduced, thereby reducing the peeling of the column nails caused by alternating stress fatigue. As for the difficulty of precision hole machining, the present application uses 42CrMo material instead of 33NiCrMoV14-5 (German standard) material. Its strength can meet the requirements of the roller sleeve, but its hardness is much lower than that of 33NiCrMoV14-5 (German standard) material. The wear of 33NiCrMoV14-5 (German standard) material is also faster than that of the original column nail. In view of the column nail of the present invention with greatly improved wear resistance, the present invention punches holes around the column nail hole on the 42CrMo material substrate and embeds wear-resistant nails. The wear-resistant nails are preferably made of high-speed steel, which divides the non-column nail part of the roller sleeve surface into small areas to cut off the flow path of micro-wear. Practice shows that the wear rate of the substrate surface protected by the high-speed steel wear-resistant nails is basically synchronized with the wear speed of the column nails of the present invention.

[0046] The amount of material passing through the sides of the roller surface is less than that in the middle, so the extension amount of the studs can be appropriately reduced. The present invention improves the wear resistance of the studs in the middle and increases the difference in wear resistance with the carbide studs on the sides of the roller surface. If the amount of material passing through the sides is less than that in the middle, or the protruding height of the studs on the sides of the roller surface is 1-3mm lower than that in the middle, the absolute allowable difference between the studs in the middle and the studs on the sides can be increased during use by lowering the studs on the sides in advance. The carbide studs on the sides of the roller surface are preferably YG11, and the protruding height is 1-3mm lower than that in the middle, and the protruding length is 2-4mm.

[0047] The above measures strengthen the matrix and increase its toughness, which can improve its fatigue resistance to 3~4 times under the condition of high-pressure roller pellet crushing. The added NbC has a higher hardness than WC, and the pure wear resistance of the column nails of the present invention is improved by more than 30%; for the column nails produced, under the same working conditions, the amount of material worn per millimeter of the middle column nail is actually increased by about 4 times compared with the prior art solution; in addition, due to the significant improvement in the strength and toughness of the column nails, when iron foreign matter enters, the column nail will not break but the protruding part will break, and the column nail will still be firmly in the hole, protecting the roller surface together with the wear-resistant nails inlaid on the roller sleeve surface, and avoiding rapid wear of the matrix to form deep pits; at the same time, when the maximum wear amount of the column nails proposed by the present invention is 20mm, the inner concavity can be preferably controlled to be within 4mm.

[0048] Under the permissible operating index conditions, the life of the high-pressure roller sleeve is extended to 2 years or higher multiples of 2 years. The operation of the high-pressure roller of the present invention selects the same long-life mode as the operation control standard. The length of the carbide spherical head column nail in the middle area of ​​the roller surface is preferably 35mm, the length of the conical head column nail is preferably 30mm, the permissible wear length is 20mm, and the axial concavity of the roller surface column nail is allowed to be 6mm, preferably controlled to be 4mm; when a certain high-pressure roller is actually in operation for 18 months, the column nail wear is 15mm, and the concavity is 10mm, reaching the lower limit standard, and its life is 1.5 years. The permissible wear amount of this scheme is 20mm, because the wear resistance of the column nail is 4 times the amount of overfeed when the wear amount is the same, which is equivalent to the permissible wear amount of the original column nail of 80mm. At this time, the maximum concavity is only 6mm, so its service life can reach 80 / 15*1.5=8 years, and the extended life is 4 integer digits of 2 years.

[0049] With a life cycle of 2 years, within the 2-year life cycle, its operating indicators are improved to achieve high-efficiency and stable operation. The operation of the high-pressure roller in this application selects the same life cycle high operation control standard mode. The length of the carbide spherical head studs in the middle area of ​​the roller surface is preferably 25mm, the length of the conical head studs is preferably 20mm, the allowable wear length is 10mm, and the high standard allowable axial concavity of the roller surface studs is 3mm, preferably controlled to 2mm. When a high-pressure roller is actually in operation for 24 months, the column nail wear is 25mm and the inner concavity is 20mm. When the actual wear is 12.5mm, the inner concavity has reached the lower limit standard, and its actual effective life is only 1 year. The allowable wear of the present invention is 10mm. Because the wear resistance of the column nail is 4 times the amount of overfeed when the wear amount is the same, it is equivalent to the original allowable wear of 40mm. At this time, the maximum inner concavity is only 3mm, and its service life can reach 40 / 12.5*1=3.2 years, which can ensure that its operating indicators are improved within the 2-year life cycle and achieve high-efficiency and stable operation.

[0050] The two end faces of the existing high-pressure roller sleeve are generally equipped with high-quality CrC series wear-resistant lining plates, such as 6+4 wear-resistant plates of Vautⅰd-100, but their wear resistance is still relatively low, and they need to be replaced regularly during use, which increases the maintenance intensity. They are often out of repair due to insufficient maintenance time, resulting in excessive wear of the ends, causing the studs on the edge of the roller surface to fall off and causing local collapse. The present invention uses a nickel-chromium alloy with a WC content of more than 60% on the two end faces of the roller sleeve, and the width of the surfacing ring on both ends is about 100-120mm, and the thickness is about 5-10mm (the thickness of the long-life solution is 10mm, and the thickness of the high-efficiency solution is 5mm). The roller cover is edged, and the surfacing width is about 10mm and the thickness is about 4-5mm; the wear resistance of this material is about 10 times that of Vautⅰd-100, and it is thickened for long-life use. Practice has proved that it can ensure that the two ends will not be worn and failed during the entire use cycle, and solve the problem of local collapse caused by the studs on the edge of the roller surface falling off.

[0051] In the existing high-pressure rollers, the roller sleeves are mounted on the roller shafts. The thickness of the roller sleeves is relatively thick, which makes forging and processing difficult. The present invention turns off a layer of the original thick roller sleeves, and the turning thickness is about 100-120mm. The original thin roller sleeves are used as intermediate transition sleeves, and the roller sleeves of the present invention are installed on the outer layer. The length of the roller sleeves varies from 600 to 1800mm for different high-pressure roller models. If the shaft and the sleeves are fully interfered with in a single size, once they are eccentric or not smoothly installed during installation, they are very easy to get stuck. At this time, it will be extremely difficult to pull out and reinstall. The present invention changes the single size of the full-segment interference fit into a stepped multi-segment multi-size fit. The number of steps is preferably 3 to 4, and the step diameter difference is preferably 5 to 10mm. After interference assembly, the two ends are welded and reinforced. The assembly stroke is only one-third of the multi-segment, and the formation of a guided structure will not be eccentric during the assembly process, greatly reducing the interference fit installation of the hole shaft under the long ruler.

[0052] Based on the above technical solution, the present invention provides the following partial embodiments:

[0053] Example 1

[0054] A wear-resistant and long-life high-pressure roller sleeve for crushing sintered pellet ore powder, such as Figure 6 As shown, the outer surface of the roller sleeve is surrounded by carbide studs and is inlaid with wear-resistant studs;

[0055] The cemented carbide studs in the non-roller surface middle area of ​​the roller sleeve are sintered by a WC cobalt-based alloy containing 5% by volume of nano-grade WC and TIC and an appropriate amount of rare earth yttrium, and 2% of Cr is added;

[0056] like Figure 7 As shown in the figure, the wear resistance of the carbide studs on both sides of the roller surface of the roller sleeve is lower than that in the middle, or the protruding height is 1mm lower than that in the middle;

[0057] Both ends of the roller sleeve are welded with nickel-chromium-boron-silicon based alloy containing more than 60% WC;

[0058] like Figure 8 As shown, the roller sleeve and the roller shaft are assembled by interference fit of multi-step shaft holes.

[0059] like Fig. 9 As shown, the material of the wear-resistant nail is high-speed steel or hard alloy, with a diameter of 5mm and a length of 8mm. The end of the wear-resistant nail is flush with the surface of the roller sleeve.

[0060] The bending strength of cemented carbide studs is greater than 3500MPa, and the diameter is 16mm. Fig.10 As shown, the head of the column nail is spherical and the length of the column nail is 20mm;

[0061] like Fig.11 As shown, a hole is drilled on the roller sleeve body, and the stud is pressed into the hole with an interference fit of 0.04mm, and the extension length is 4mm;

[0062] like Fig.12 As shown, both ends of the roller sleeve are clad with nickel-chromium alloy containing more than 60% WC, the cladding ring width at both ends is 100mm, the thickness is 5mm, the roller cover edge, the cladding width is 10mm, the thickness is 4mm;

[0063] like Fig.13 As shown, the roller sleeve and the roller shaft are assembled by interference fit of multi-step shaft holes. The roller sleeve is made of 42CrMo, with a thickness of 100mm, 3 steps, and a step diameter difference of 5mm. After interference fit, both ends are welded and reinforced.

[0064] The cemented carbide studs in the middle area of ​​the non-roller surface of the roller sleeve are sintered by a WC cobalt-based alloy containing 5% by volume of nano-grade WC and TIC and an appropriate amount of rare earth yttrium. The particle size of the nano-grade WC and TIC is 50nm. The Y particles are ball-milled together with the 3um WC particles. When the 3um WC particles are ball-milled to 1.4um, the powders are combined and sintered to make the cemented carbide studs in the middle area of ​​the roller surface.

[0065] When the high-pressure roller is running in the same operation control standard longevity mode, the length of the carbide ball head stud in the middle area of ​​the roller surface is 35mm, the length of the conical head stud is 30mm, the allowable wear length is 20mm, and the axial concavity of the roller surface stud is allowed to be 6mm;

[0066] When the high-pressure roller is running in the same life cycle high operation control standard mode, the length of the carbide spherical head studs in the middle area of ​​the roller surface is 25mm, the length of the conical head studs is 20mm, the allowable wear length is 10mm, and the high standard allowable axial concavity of the roller surface studs is 3mm.

[0067] Example 2

[0068] A wear-resistant and long-life high-pressure roller sleeve for crushing sintered pelletized ore powder, wherein the outer surface of the roller sleeve is surrounded by hard alloy studs and is inlaid with wear-resistant studs;

[0069] The cemented carbide studs in the non-roller surface middle area of ​​the roller sleeve are sintered from a WC cobalt-based alloy containing 8% by volume of nano-grade WC and appropriate amounts of rare earth yttrium and cerium, plus 2.5% Cr and 2% NbC;

[0070] like Figure 7 As shown in the figure, the wear resistance of the carbide studs on both sides of the roller surface of the roller sleeve is lower than that in the middle, or the protruding height is 2mm lower than that in the middle;

[0071] Both ends of the roller sleeve are welded with nickel-chromium-boron-silicon based alloy containing more than 60% WC;

[0072] like Figure 8 As shown, the roller sleeve and the roller shaft are assembled by interference fit of multi-step shaft holes.

[0073] like Fig. 9As shown, the material of the wear-resistant nail is sharp steel or hard alloy, with a diameter of 7mm and a length of 12mm. The end of the wear-resistant nail is flush with the surface of the roller sleeve;

[0074] The bending strength of cemented carbide studs is greater than 3500MPa, and the diameter is 17mm. Fig.10 As shown, the head of the column nail is conical and the length of the column nail is 25mm;

[0075] like Fig.11 As shown, a hole is drilled on the roller sleeve body, and the stud is pressed into the hole with an interference fit of 0.05mm, and the extension length is 4.5mm;

[0076] like Fig.12 As shown, both ends of the roller sleeve are clad with nickel-chromium alloy containing more than 60% WC, the cladding ring width at both ends is 110mm, the thickness is 8mm, the roller cover is edged, the cladding width is 10mm, and the thickness is 4.5mm;

[0077] like Fig.13 As shown, the roller sleeve and the roller shaft are assembled by interference fit of multi-step shaft holes. The roller sleeve is made of 42CrMo, with a thickness of 110mm, 3 steps, and a step diameter difference of 8mm. After interference fit, both ends are welded and reinforced.

[0078] The cemented carbide studs in the middle area of ​​the roller surface of the roller sleeve are sintered by a WC cobalt-based alloy containing 8% nano-grade WC and appropriate amounts of rare earth yttrium and cerium in a volume ratio. The particle size of the nano-grade WC is 70nm. The Y and Ce particles are ball-milled together with the 3um WC particles. When the 3um WC particles are ball-milled to 1.5um, the powders are combined and sintered to make the cemented carbide studs in the middle area of ​​the roller surface.

[0079] When the high-pressure roller is running in the same operation control standard longevity mode, the length of the carbide ball head stud in the middle area of ​​the roller surface is 35mm, the length of the conical head stud is 30mm, the allowable wear length is 20mm, and the axial concavity of the roller surface stud is allowed to be 4mm;

[0080] When the high-pressure roller is running in the same life cycle high operation control standard mode, the length of the carbide spherical head studs in the middle area of ​​the roller surface is 25mm, the length of the conical head studs is 20mm, the allowable wear length is 10mm, and the standard allowable axial concavity of the roller surface studs is 2mm.

[0081] Example 3

[0082] A wear-resistant and long-life high-pressure roller sleeve for crushing sintered pelletized ore powder, wherein the outer surface of the roller sleeve is surrounded by hard alloy studs and is inlaid with wear-resistant studs;

[0083] The cemented carbide studs in the middle non-roll surface area of the roll sleeve are sintered from a WC cobalt-based alloy containing 10% by volume of nano WC and TiC, appropriate amounts of rare earth yttrium and cerium, and additionally 3% Cr and 5% NbC;

[0084] As Figure 7 shown, the wear resistance of the cemented carbide studs in the two edge areas of the roll surface of the roll sleeve is lower than that in the middle, or the protruding height is 3 mm lower than that in the middle;

[0085] The two end faces of the roll sleeve are surfacing welded with a nickel-chromium-boron-silicon-based alloy containing more than 60% WC;

[0086] As Figure 8 shown, the roll sleeve and the roll shaft are assembled by interference fit of multi-stage stepped shaft holes.

[0087] As Fig. 9 shown, the material of the wear-resistant studs is high-speed steel or cemented carbide, with a diameter of 8 mm and a length of 15 mm. The end of the wear-resistant stud is flush with the surface of the roll sleeve;

[0088] The bending strength of the cemented carbide studs is greater than 3500 MPa, and the diameter is 18 mm. As Fig.10 shown, the head of the stud is spherical or conical, and the length of the stud is 35 mm;

[0089] As Fig.11 shown, holes are drilled on the roll sleeve body, and the studs are hot-pressed into the holes with an interference of 0.06 mm, and the protruding length is 5 mm;

[0090] As Fig.12 shown, the two end faces of the roll sleeve are surfacing welded with a nickel-chromium alloy containing more than 60% WC. The width of the surfacing welding ring on both ends is 120 mm, the thickness is 10 mm, the roll surface is edged, the width of the surfacing welding is 10 mm, and the thickness is 5 mm;

[0091] As Fig.13 shown, the roll sleeve and the roll shaft are assembled by interference fit of multi-stage stepped shaft holes. The material of the roll sleeve is 42CrMo, the thickness is 120 mm, the number of steps is 4, the diameter difference of the steps is 10 mm, and both ends are welded and reinforced after interference fit.

[0092] The cemented carbide studs in the middle area of the roll surface of the roll sleeve are sintered from a WC cobalt-based alloy containing 10% by volume of nano WC and TiC, appropriate amounts of rare earth yttrium and cerium. The particle sizes of nano WC and TiC are 100 nm. Other component particles are ball-milled together with 3 um WC particles. When the 3 um WC particles are ball-milled to 1.6 um, the powder mixture is sintered to make the cemented carbide studs in the middle area of the roll surface.

[0093] When the high-pressure roller is running in the same operation control standard longevity mode, the length of the carbide ball head stud in the middle area of ​​the roller surface is 35mm, the length of the conical head stud is 30mm, the allowable wear length is 20mm, and the axial concavity of the roller surface stud is allowed to be 4mm;

[0094] When the high-pressure roller is running in the same life cycle high operation control standard mode, the length of the carbide spherical head studs in the middle area of ​​the roller surface is 25mm, the length of the conical head studs is 20mm, the allowable wear length is 10mm, and the standard allowable axial concavity of the roller surface studs is 2mm.

[0095] The product prepared by the present invention was tested for performance, and the results are as follows:

[0096] Test 1, wear amount:

[0097] The column nails in this case were tested several times, and the comparative data under the same working conditions and the same duration are as follows:

[0098] ①, 1400 (diameter) * 800mm (width) high pressure roller made in Germany:

[0099] The wear amount of the original stud in the length direction: 25mm;

[0100] The wear of the column nail in the length direction in this case: 5mm;

[0101] ②, 2000 (diameter) * 1500mm (width) high pressure roller made in Germany:

[0102] The wear of the original stud in the length direction: 32mm;

[0103] The wear of the column nail in the length direction in this case: 6mm;

[0104] The actual measurement shows that the wear of the column nails in this case under the same working conditions and the same time is only 1 / 5 of the wear of the original column nails.

[0105] Test 2, wear life:

[0106] The wear amount of this case under the same working conditions and the same time is only 1 / 5 of the original. Taking the margin into consideration, the wear resistance of this case is calculated as 4 times;

[0107] The permissible wear in this case is set at 20 mm, which is equivalent to 4 times the original wear, which is 80 mm;

[0108] The original column nails (see Test 1) were worn 15mm after 1.5 years of use. The allowable wear of 20mm for the column nails in this case is equivalent to the time when the original column nails were worn 80mm. The wear-resistant life of the column nails in this case is 80 / 15*1.5=8 years.

[0109] The present invention solves the problem that the crushing efficiency in the current roller crushing of pellets is difficult to maintain for a long time, creates conditions for the stable and continuous production of pellets, and high-grade pellets lay the foundation for the efficient production of subsequent blast furnaces. Compared with the prior art, the present invention can greatly reduce the wear of cemented carbide in the length direction under unit crushing volume, maintain the flatness of the roller surface column nails for a long time, maintain the stability of the extended length of the column nails, resist the formation of deep pits on the roller surface due to the entry of foreign matter, prevent the edge of the roller sleeve from collapsing, and facilitate the replacement and installation of the roller sleeve. The use of the present invention can greatly increase the service life and achieve continuous and efficient crushing effect during use.

[0110] The above shows and describes the basic principles, main features and advantages of the present invention. It is obvious to those skilled in the art that the present invention is not limited to the details of the above exemplary embodiments, and that the present invention can be implemented in other specific forms without departing from the spirit or basic features of the present invention. Therefore, no matter from which point of view, the embodiments should be regarded as exemplary and non-restrictive. The scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims are included in the present invention.

[0111] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A wear-resistant and long-life high-pressure roller sleeve for crushing sintered pellet ore powder, characterized in that: The outer surface of the roller sleeve is surrounded by hard alloy studs and is inlaid with wear-resistant studs; The hard alloy studs in the middle area of ​​the roller surface of the roller sleeve are sintered from a WC cobalt-based alloy containing 5-10% by volume of nano-grade WC or / and TIC and an appropriate amount of rare earth yttrium or / and cerium; The wear resistance of the carbide studs on the sides of the roller surface of the roller sleeve is lower than that in the middle, or the protruding height is 1-3mm lower than that in the middle; The wear-resistant nail is made of high-speed steel or hard alloy, with a diameter of 5-8 mm and a length of 8-15 mm. The end of the wear-resistant nail is flush with the surface of the roller sleeve; The WC cobalt-based alloy of the cemented carbide studs in the middle area of ​​the roller surface of the roller sleeve also contains 2-3% by volume of Cr and 2-5% by volume of NbC; The bending strength of the cemented carbide studs in the middle area of ​​the roller surface is greater than 3500MPa, the diameter is 16-18mm, the stud head is spherical or conical, and the stud length is 20-35mm; Holes are drilled on the roller sleeve body, and the studs are pressed into the holes with an interference fit of 0.04 to 0.06 mm, and the extension length is 4 to 5 mm. The two end surfaces of the roller sleeve are clad with nickel-chromium alloy containing more than 60% WC, the cladding ring width at both ends is 100-120mm, the thickness is 5-10mm, the roller cover edge, the cladding width is 10mm, the thickness is 4-5mm; The roller sleeve and the roller shaft are assembled by interference fit of multi-step shaft holes. The roller sleeve is made of 42CrMo, with a thickness of 100-120mm, 3-4 steps, and a step diameter difference of 5-10mm. After interference fit, both ends are welded and reinforced. The particle size of nano-scale WC and / or TIC is 50-100nm. The other component particles are ball-milled together with the 3um WC particles. When the 3um WC particles are ball-milled to 1.4-1.6um, the powders are assembled and sintered to make the cemented carbide studs in the middle area of ​​the roller surface.

2. The wear-resistant and long-life high-pressure roller sleeve for crushing sintered pellet ore powder according to claim 1 is characterized in that: When the high-pressure roller is running in the same operation control standard longevity mode, the length of the carbide ball head stud in the middle area of ​​the roller surface is 35mm, the length of the conical head stud is 30mm, the allowable wear length is 20mm, and the axial concavity of the roller surface stud is allowed to be 4-6mm; When the high-pressure roller is running in the same life cycle high operation control standard mode, the length of the carbide spherical head studs in the middle area of ​​the roller surface is 25mm, the length of the conical head studs is 20mm, the allowable wear length is 10mm, and the axial concavity of the roller surface studs is allowed to be 2-3mm.

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