RU2016658C1 - Lining plate - Google Patents

Abstract

FIELD: mechanical engineering. SUBSTANCE: plate with a wave-shaped working surface has a steel base and reinforcing inserts in the form of truncated cones from a white austenite cast iron fastened in the steel base at a step multiple of 1.5-3.0 of the maximum diameter which is within 30 -70 mm. The reinforcing inserts are fastened flush with the working surface in the steel base. The rows of inserts are inclined to the motion direction of the ore mass by a value of 1.0-2.0 of the setting step. EFFECT: improved structure. 3 dwg, 1 tbl

Description

 The invention relates to the field of engineering, in particular, to the design of the lining plates of ore-grinding mills for the armor of the intake heat of rotary excavators, the lining of the bottom of the bucket of excavators, etc.

 The specified parts and assemblies of mining machinery units belong to the category of wearing parts.

 Especially low service life of linings of rod mills working in the first stage of grinding, which in some cases does not exceed 5-6 months. continuous work.

 The lining of the drum of large diameter grinding mills (3.2 m or more) consists of left steel grade 110G13L and is subject to intense abrasion and the effects of significant dynamic loads.

 Known heel lining plate with spherical protrusions on the working surface, which is less susceptible to wear due to the specifics of the design itself, which prevents the intensive movement of abrasive material on the surface of the lining during rotation of the mill, thereby reducing the contact effect of the abrasive mass on the surface of the lining [1] .

 A disadvantage of the known lining plate is the low productivity of the mills due to the limited movement of the processed material and the reduction of its grinding speed, as well as increased energy consumption.

 Known lining plate with protrusions on the working surface of a wear-resistant material, fixed in a steel base plate [2].

 To increase the impact resistance and service life of the lining plate, the protrusions are made spherical in shape with the center of the sphere located inside the base and vertical grooves filled with the base metal - steel.

 A disadvantage of the known design is the low impact resistance of spherical protrusions made of a wear-resistant alloy having insufficient strength properties and low resistance to shock loads.

 The steel base filling the vertical grooves in the inserts does not provide reliable protection against impacts of grinding media (rods, balls), which leads to the destruction of wear-resistant cast iron inserts to reduce the service life.

 The destruction of the protrusions from wear-resistant cast iron in all cases will occur primarily during the loading of grinding media and even more so during the break-in of the mill at idle for several hours before putting it into operation.

 Another significant drawback of the known plate is the abrasive wear of the metal base in the spaces between the rows of wear-resistant inserts in the direction of movement of the ore mass. The closest technical solution is a wave profile lining plate containing a steel base and reinforcing inserts of white austenitic cast iron in the form of truncated cones. The inserts are fixed in a steel base with a step that is a multiple of 1.5-3.0 of the maximum diameter lying within 30-70 mm [3].

 The disadvantages of the known design of the lining plate is that with a significant increase in service life due to the good protection of the reinforcing inserts from impacts of grinding media when loading the mills and idling, the steel base of the lining plate is subject to significant wear during operation.

 In order to prevent rupture of metal during plate manufacture, reinforcing inserts are fixed in a steel base at a sufficiently large distance from each other, equal to 1.5-3.0 mm of maximum diameter, which does not provide complete protection of the steel base from abrasive wear in the gaps between the rows of inserts .

 Bulk ore materials subjected to grinding are moved along with grinding media along an annular line and thereby abrade the softer steel base of the lining plates, which ultimately reduces the service life of the lining.

 In addition, the design of the lining plate is complicated.

 The aim of the invention is to increase the service life of the lining plate and simplify its design.

 This goal is achieved by the fact that in the lining plate with the working surface of the wave profile, containing a steel base and reinforcing inserts in the form of truncated cones of white austenitic cast iron, fixed in a steel base in increments of 1.5-3.0 of their maximum diameter lying within 30-70 mm, the reinforcing inserts are fixed in a steel base flush with the working surface, and the rows of inserts are inclined to the direction of movement of the ore mass by a value of 1.0-2.0 setting steps.

 In FIG. 1 shows a lining plate (section AA); in FIG. 2 - lining plate with a wave working surface, reinforced with wear-resistant cast iron inserts, general view; in FIG. 3 is a diagram of the protective effect of wear-resistant lining inserts on the wear of a steel substrate, depending on their location relative to the flow direction of the abrasive ore mass.

 The lining plate consists of a steel base 1 wave profile, reinforcing inserts 2 in the form of truncated cones of wear-resistant alloy.

 The plate is equipped with mounting loops 3 and holes 4 for mounting to the drum using bolted connections.

 The reinforcing inserts 2 are fixed in the steel base 1 with the pitch T, equal to 2-3 diameters of the inserts. The rows of inserts 2 are inclined to the direction B of the ore mass flow movement by 1.0-2.0 steps of setting T.

 Lining plate works as follows.

 Before the mill is put into operation, the grinding media are loaded. Grinding bodies, for example, for rod mills, are steel rods with a diameter of 100-125 mm and a length slightly shorter than the mill itself.

 The grinding bodies are loaded within 40-50% of the drum volume, i.e. from 60 to 275 tons, depending on the size of the mill.

 After loading the grinding bodies and preliminary rolling of the mill at idle for several hours, the bolt fasteners of the linings are additionally tightened.

 When the mill is idling, the shock loads on the lining plates are maximum.

 Wear-resistant inserts, mounted in a steel base flush with the working surface, are less susceptible to shocks when loading grinding media, when running at idle, as well as during operation, and the location of the inserts in rows with an inclination to the direction of ore flow by 1.0-2 , 0 steps of their installation, thanks to the shadow effect, protects the metal base from wear, because when tilting rows of inserts, each separately standing wear-resistant insert is offset from the stream stream of ore mass by a certain amount and protects part of the surface of the base from abrasive wear.

 Examples of specific performance of the device are shown in the table. The lining plate contains a base made of high-manganese steel grade 1210 G13L and reinforced with inserts made of white austenitic cast iron grade 250 x 28N2. The reinforcing inserts have the shape of a truncated cone, the smaller of which is located on the working surface of the steel base flush with it.

 The inserts with a diameter of 50 mm are fixed in a steel base with a pitch of 75 mm and are arranged in rows inclined to the direction of movement of the ore mass (direction of movement of the ore mass parallel to the smaller side of the plate) by 75 mm.

 The reinforcing inserts are located on the diagonal of a right-angled triangle, the greater side of which coincides with the direction of movement of the ore mass, less than t is equal to the pitch of setting T.

 Reducing the slope of a number of reinforcing inserts (less than one step of placement) leads to insecurity of part of the working surface of the base in the row spacing.

 In cases of the location of reinforcing inserts with a slope of rows of more than 2 steps from the arrangement, leads to the appearance of free zones of the base unprotected from wear.

 Feasibility study of the use of the lining plate is to significantly increase the service life of the lining and simplify the design of the lining plates.

 The operation of mills with linings of the proposed design will allow consumers to reduce current costs for repair and restoration.

 Implementation of the proposed design of the lining plate is provided for at the Novo-Kramatorsk Machine-Building Plant for ore-grinding mills with a diameter of 3.6 m or more.

Claims (1)

 Lining plate with a working surface of the wave profile, containing a steel base and reinforcing inserts in the form of truncated cones of white austenitic cast iron, fixed in a steel base with a step that is a multiple of 1.5 - 3.0 of their maximum diameter lying within 30 - 70 mm, characterized in that, in order to increase the service life and simplify the design, the reinforcing inserts are fixed in a steel base flush with the working surface, and the rows of inserts are inclined to the direction of movement of the ore mass by a value of 1-2 steps of setting.

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