RU2772823C1 - Lining of the feed funnel of the trunnion of the drum mill - Google Patents

Abstract

FIELD: equipment for grinding materials.

SUBSTANCE: invention relates to equipment for grinding materials, in particular to means for protecting the internal surfaces of loading drum mills, and can be used in metallurgical, mining, construction, chemical and other industries in the processes of grinding lumpy materials. The lining of the loading funnel of the trunnion of the drum mill consists of plates connected to each other by longitudinal side surfaces to form a conical branch pipe, and having protrusions in the form of ribs from the side of the working surface. The protrusions are inclined relative to the axis of symmetry of the plates. In addition to plates with ledges, the lining includes plates without ledges, which alternate with each other. The plates are connected to each other in a groove along the entire length, while holes for bolted fasteners are made for fastening to the loading funnel on the side of its smallest diameter. Each plate on the side directed into the drum has a bend, which forms a ring like a flange when assembling the lining. For fast and affordable mounting, each liner has at least two mounting lugs.

EFFECT: lining is characterized by a long service life and reduces labor costs during its maintenance.

4 cl, 5 dwg

Description

The invention relates to equipment for grinding materials, and is intended to protect the internal surfaces of the feed funnels of the trunnions of drum mills from abrasive wear, and can be used in the metallurgical, mining, construction, chemical and other industries in the processes of grinding lumpy materials.

From the prior art, the invention "Drum mill loading trunnion" is known (SU patent No. 1036368 dated May 28, 1982, B07B 17/18, published on August 23, 1983). The loading trunnion of the drum mill contains a hollow body and a lining of its inner surface. In order to reduce wear of the inner surface of the trunnion, it is made with a conical bushing placed in its cavity, on the smaller base of which a reflector in the form of a truncated cone is mounted, and the larger base of the bushing and the smaller base of the reflector are turned into the mill drum. The aim of the invention is to reduce the wear of the inner surface of the trunnion body by abrasive pulp circulating in the gap "trunnion body - trunnion lining" by eliminating the causes of circulation.

The disadvantages of this design of the invention is that the bolted fasteners of the lining of the conical bushing, on the side of the largest diameter of the conical bushing, are made through the trunnion, which makes it difficult to replace them unsafely, since the nuts are located between the end wall of the drum and the bearing. Bolted fasteners are in the working area, which leads to wear of the bolt head and its breakage. Also, the absence of a coupling between the linings contributes to the breakage of the bolts, since during the rotation of the mill, the flow of ore and grinding balls from the loading device, a moment of force is created, pulling the lining in the lower part at the unloading in the opposite direction of rotation, and this creates additional intense friction of the bolt body at the base of the head . The presence of a technological gap between the linings leads to through wear between the linings of both the lining itself and the rubber lining. Requires frequent replacement of lining, rubber backing and bolting.

Known technical solution (utility model) "Trum mill lining" (patent RU No. 110293 dated December 31, 2010, B02C 17/22, published on November 20, 2011). The lining of the drum mill, consisting of a set of lining plates forming a wave working surface, each of which is made of an elastomeric material, is installed on the inner surface of the mill drum and provided with grooves made in the longitudinal direction, the working surface of each lining plate consists of a plate located in the central part a crest in the form of a truncated cone and asymmetric lateral recesses, while the wider recess is made with a protrusion, and the recess of a smaller width with a groove that serves for reciprocal interaction with a number of mounted plates.

The disadvantage of this technical solution is that such a lining of a drum mill is justified only for lining the periphery of the drum and only for mills with a small class of loaded material and when unloading into a hopper or trunnion lined with elastic lining plates from a loading device of the size and volume of ore, grinding balls, for example, as in wet semi-autogenous grinding mills, the fasteners of elastic lining plates are deformed from impacts, fragments of the wave ribs of modular elements are intensively worn and, as a result, the nozzle is filled due to the cylindrical working surface. The use of this type of flexible lining plates in the feed funnel or trunnion does not protect their fasteners from impacts with ore and grinding balls, which in turn leads to breakage of the lining plates and wear of the loading trunnion or funnel in open areas. The wave working surface of elastic lining plates does not ensure the unloading of ore from the loading trunnion or loading funnel. The circulation of the material in the hopper or trunnion leads to intensive wear of the elastic lining plates, which reduces the service life and requires frequent replacement. The straight groove of elastic lining plates, when used in a hopper or trunnion, does not provide adhesion between the lining plates, which causes even greater wear of the bolted fasteners, this leads to the breakage of the plates. The use of this type of flexible lining plates in the hopper or trunnion is impractical and leads to the loss of the essence of the invention.

Also known is the invention "The lining of a drum mill" (patent RU No. 2266789 dated 14.06.2001, B02C 17/22, publ. 27.12.2005). The lining of a drum mill, having a cylindrical body, in which the material to be ground is placed and a mass of grinding bodies, consisting of rings formed by separate lining plates adjacent to each other, which from 5 to 15% of the total number of lining plates contain a reflector having a rib, installed end face on its base plate at an angle relative to the plane perpendicular to the longitudinal axis of the mill, directed either to the inlet or outlet of the mill and less than 25 degrees, while the locations of the reflectors are chosen in such a way that all the reflectors together form a spiral configuration, continuous or intermittent to achieve the desired effect.

The disadvantage of this invention is that such a lining of a drum mill is justified only for lining the periphery of the drum and only for mills with a small class of loaded material and when unloading into a lined hopper or trunnion from a boot device of the size and volume of ore, grinding balls, for example, as in wet semi-autogenous grinding mills, the destruction of ceramic plates on the ribs and rapid wear of the ribs occur. The small angle of inclination of the ribs does not ensure the collision of ore and grinding balls from the feed funnel or pin, does not ensure their advancement into the mill drum. The low angle of inclination of the ribs also accelerates their wear in the hopper or trunnion. The location of the oblique rib at the edge of the slab leads to intense wear of the bolt fasteners due to the pressure lever on the bolt fastener from the slab under the action of ore and grinding balls on the rib when the mill drum rotates. The use of this type of lining in a hopper or trunnion is impractical and leads to the loss of the essence of the invention. Breakage of the lining and a small angle of inclination of the rib leads to the circulation of the material in the hopper or trunnion, which leads to intensive wear of the lining itself and the open surface of the hopper or trunnion.

The closest in technical essence and the achieved result is the invention "The lining of the trunnion of a drum mill and a kit for its manufacture" (patent RU No. The lining of the trunnion of a drum mill, containing longitudinal modular elements connected to each other by longitudinal side surfaces to form a branch pipe with a conical inner working surface. Each modular element has at least one protrusion on the side of the working surface, made integral with the modular element and forming a helical rib with the protrusions of other modular elements, while one end surface of at least one protrusion of each modular element lies in the same plane with the corresponding longitudinal side surface of the modular element. The use of the above lining, in particular, makes it possible to reduce the complexity of the assembly and disassembly of modular elements by simplifying the sealing and fastening operations.

The disadvantage of this invention is that such a nozzle is justified only for mills with a small class of loaded material, and when unloading into the nozzle from the loading device the size and volume of ore, grinding balls, for example, as in wet semi-autogenous grinding mills, the straps of fastening modular elements and fasteners are deformed strips from impacts, intensive wear of the protrusions of modular elements occurs and, as a result, backfilling of the branch pipe due to the insufficient angle of inclination of the conical working surface. The use of elastic modular inserts does not protect their fasteners from impacts with ore and grinding balls, which, in turn, leads to breakage of modular elements and wear of the pin in open areas. The use of bolted fasteners in the working area also leads to its rapid wear and, as a result, leads to breakage of modular elements and wear of the trunnion in open areas. The circulation of material over a conical surface with a small angle of inclination leads to intensive wear of the nozzle, which reduces the service life and requires frequent replacement. A large number of modular elements does not provide quick installation and replacement of nozzle elements. Mounting of elements requires precise installation of numerous fasteners in the trunnion. The absence of grooves between modular elements requires high precision in the manufacture of elements, as well as additional sealing work.

The technical problem of the present invention ispromotion reliability hopper lining, increasing its service life and reducing labor costs for installation and repairs in the hopper.

The technical problem is solved due to the fact that the lining of the loading funnel of the trunnion of the drum mill consists of plates connected to each other by longitudinal side surfaces to form a conical pipe having protrusions in the form of ribs from the side of the working surface, while the protrusions are inclined relative to the axis of symmetry of the plates ; in addition to plates with protrusions, the lining includes plates without protrusions, which alternate with each other, while the plates are connected to each other in a groove along the entire length, and holes for bolt fasteners are made for fastening to the hopper on the side of its smallest diameter; each plate from the side directed into the drum has a bend, which forms a ring like a flange when assembling the lining.

For fast and affordable mounting, each liner has at least two mounting lugs.

The present invention is illustrated by drawings:

Figure 1 shows a section of the hopper;

Figure 2 shows a fragment of a section of the grooves of the lining plates along A-A;

In FIG. 3 shows the reverse side of the lining plate with a protrusion in the form of a rib;

In FIG. 4 shows the reverse side of the lining plate without the protrusion;

In FIG. 5 shows the complete lining (view from the side of the largest diameter).

The description of the invention is presented on the example of installation in the feed funnel 1 of the trunnion of the drum mill 2, which consists of a conical sleeve 3 pasted over with a replaceable rubber lining 4 and connected to the flange 5 on the side of the smaller diameter and the ring 6 on the side of the larger diameter. The conical bushing has stiffeners 7, which are also connected to the ring 6 and the flange 5, the flange 5 has holes 8 opposite to the bolt fastening 9 of the lining plates. The lining of the loading funnel of the trunnion of the drum mill (hereinafter referred to as the lining) consists of two types of plates, the first type 10 has a ledge 11 in the form of a rib inclined relative to the axis of symmetry of the plate by the width of each plate, the second type 12 without a ledge. The plates are mounted through one in turn, forming a conical pipe, while the lining has an equal number of plates of the first 10 and second type 12, which creates a sufficient distance between the protrusions 11 and due to the speed of rotation of the mill drum 13, a sufficiently accumulated mass of ore is pushed into the mill drum more efficiently , which helps to reduce the wear of the upper row of the lining of the end loading wall 14, which is joined to the lining. In addition, due to the effective pushing of the accumulated mass of ore into the mill drum, the circulation of ore and grinding balls through the lining is minimized, which prolongs its service life. Each lining plate, on the side directed into the drum, has a bend 15, which stiffens the entire lining, wedging the plates between each other, due to which the lining is securely fixed in the hopper 1, which makes it possible to place holes for bolt fasteners 16 of each lining plate in non-working zone 17. In this case, the non-working zone 17 is a part of the lining plate, from the side of the loading device, on which ore and grinding balls do not fall when unloading from the loading device installed in the trunnion of the drum mill. The bending of the plate 15 also dampens the torques generated when the projections 11 push the ore and grinding balls, which ensures the integrity of the bolt fastener 9.

The bending of the plates 15 of the lining allows you to remove the great influence of the weight of the plates on the bolt fastener 9, which is formed when each plate is at the top point during the rotation of the mill drum, which ensures the reliability of the bolt fastener 9 and guarantees the absence of its breakage and further breakage of the plate itself. The bend of the lining 15 has a beveled end part 18, which makes it possible to easily dismantle the upper row of the lining of the end loading wall 14, which is joined to the lining.

Due to the placement of holes for bolted fasteners 16 not in the working area 17, it is possible to service bolted fasteners at arm's length through the holes in the flange 8 of the hopper 1.

Each lining plate has a fastening groove 19, which provides adhesion between the plates. The joint 20 between the two sides of the groove 19 has a curved shape, which ensures the distribution of the load on adjacent plates from the impact of ore and grinding balls. The presence of the groove 19 prevents the material from penetrating under the lining, thereby preventing the circulation of the material under the lining, which prevents the wear of the rubber lining 4 and, as a result, the wear of the conical bushing 3, which ensures an increased service life of the feed funnel 1 of the trunnion of the drum mill.

Each lining plate has two mounting lugs 21 for quick mounting.

The operation of the invention is presented on the example of loading a drum mill with wet semi-autogenous grinding.

The ore and grinding balls unloaded from the loading device installed in the trunnion of the drum mill fall into the working area 22 of the lining, then the ore and grinding balls under their own weight descend down the inclined surface of the lining and, due to the rotation of the drum 13 of the mill, are picked up by ledges 11 of the plates, which stop the circulation of ore and grinding balls in the conical sleeve 1 of the loading funnel of the pin, pushing them into the mill drum, transferring inertia from the rotation of the drum 13 of the mill, thereby pushing them away from the upper row of the lining of the loading wall 14.

The proposed invention is durable in operation, it allows you to significantly extend the useful life of the lining, significantly extend the life of the feed funnel of the drum mill pin, reduce labor costs for servicing the drum mill pin to zero for the period from the moment of installation to the complete replacement of the lining, reduces the impact of ore and grinding balls on the upper lining of the end loading wall, which reduces downtime during scheduled preventive maintenance.

From the experience of operation in wet SAG mills, the lining of the loading funnel of the drum mill trunnion does not require maintenance during the entire useful life, which reduces downtime during the routine maintenance of the mill, and the long life of the lining allows saving on the lining of the upper row of the loading wall due to the presence of a bend, which allows to reduce the size of the lining of the end loading wall in height from the loading side. From operating experience, the lining, due to the presence of a bend, grooves and protrusions in the form of a rib, lasts at least three times longer than the lining of the end loading wall.

Claims (4)

1. The lining of the loading funnel of the trunnion of a drum mill, consisting of plates connected to each other by longitudinal side surfaces to form a branch pipe, having protrusions in the form of ribs on the side of the working surface, characterized in that the branch pipe has a conical shape, the protrusions are inclined relative to the axis of symmetry of the plates , in addition to plates with ledges, the lining includes plates without ledges, which alternate with each other, while the plates are connected to each other in a groove along the entire length, and holes for bolted connections are made for fastening to the loading funnel from the side of its smallest diameter, each plate with the side directed into the drum has a bend, which forms a ring like a flange when assembling the lining. 2. The device according to claim. 1, characterized in that the holes for bolted connections are in the non-working area. 3. The device according to claim 1, characterized in that each lining plate has at least two mounting lugs. 4. The device according to claim 1, characterized in that the protrusions are located over the entire width of the plate.

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