RU2176589C1 - Method and device for producing workpieces from vulcanite abrasive compounds - Google Patents

Abstract

FIELD: abrasive industry, producing grinding, polishing and cutting-off wheel. SUBSTANCE: method contains preparing binder of forging rolls, preparing fabricated abrasive compounds, and pressing. The compound is extruded from slots provided in a die block. The extruded compound is in form of semifinished items of rectangular cross-section. The semifinished items are put one over another and placed on the moving backing. Speed of the coming out from the die block semifinished items is equal to the speed of the backing moving. The semiproduct items are put one over another forming rectangular layered workpiece with tapered front end. Device for producing workpieces contains forging rolls, press, horizontal die consisting of rectangular container 1 provided with punch 2 and die- washer 3 installed inside, die block 4 provided with horizontal slots 5 of rectangular cross-section. The backing 10 made as conveyor is mounted in front of the die block. Punch 2 extrudes vulcanite compound 8 through slots 5 of the die. Extruded semifinished items 7 are put on the backing 10 forming layered workpiece 9. EFFECT: enhanced quality and efficiency. 6 cl, 1 dwg

Description

 The invention relates to the abrasive industry, and in particular to methods and devices for preparing blanks from volcanic abrasive mass, intended for rolling sheets and obtaining grinding, polishing and cutting wheels from them.

 A known method of preparing blanks from a volcanic abrasive mass in the form of a conglomerate of different-sized flat pieces by rolling the components of the abrasive mass on a mixing roll, in which rubber is introduced into the rolls, and after it covers the rolls, a softener, sulfur, fillers, vulcanization accelerators and abrasive sequentially are introduced grain [1].

 Significant disadvantages of this method are: low productivity and uniform distribution of components in an abrasive lump. In addition, the prepared billet in the form of a conglomerate of pieces is heterogeneous, since it consists of interconnected adhesion forces of differently sized flat pieces. The supply of such a blank in the form of an inhomogeneous mass to the calender rolls for rolling sheets is difficult, and the rolled sheets have defects in the form of unformed sections (voids and friability).

 A device for preparing blanks in the form of a lump of volcanic abrasive mass, which is a mixing roller. The rollers include two rolls rotating at different speeds, devices for regulating the gap between them and a drive for rotating the rolls [2].

 The disadvantages of the device include: its low productivity, heterogeneity of mass and the different sizes of flat pieces of mass, interconnected by adhesion forces.

 There is also known a method of preparing blanks from a volcanic abrasive lump by rolling the binder components on a mixing roll, in which rubber is introduced into the rolls, and after it covers the rolls, a softener and powder components (sulfur, fillers and vulcanization accelerators) are introduced sequentially, and then by rolling ligaments on mixing rollers together with abrasive grains added to it [3].

 The separation of the operations of preparing a bunch and abrasive lump mass increases the productivity of the method. However, this method of preparing blanks from volcanic abrasive lump also leads to insufficient uniformity in the distribution of components in them. The cooked mass is also heterogeneous, because it consists of interconnected adhesion forces of differently sized flat pieces. Billet from such a heterogeneous mass makes it difficult to roll defect-free sheets from it.

 A device for preparing blanks from a volcanic lump mass is also known, which is a separately installed mixing roller for preparing a binder and preparing an abrasive lump mass. The rollers include two rolls rotating at different speeds, devices for regulating the gap between them and a drive for rotating the rolls [3].

 The disadvantages of the device include: the heterogeneity of the distribution of components in the abrasive mass and the heterogeneity of the distribution of differently sized flat pieces in the workpiece, interconnected by adhesion forces. As a result, the difficulty of feeding the workpiece from such a lump in the calender rolls for rolling sheets and defects on the sheets in the form of unformed sections.

 The closest in technical essence and the achieved effect to the proposed one is a method of preparing blanks from volcanic abrasive mass by rolling the binder components, in which rubber, softener and powder components are introduced into the rolls, rolling the finished binder with the addition of abrasive grains, and then pressing from heterogeneous lump mass of blanks of rectangular cross section [4].

 This method increases the uniformity of the mass and facilitates its feeding into the rolls of calendars for rolling sheets.

 The main disadvantages of the method are the heterogeneity of the distribution of components in the workpiece from the abrasive mass and the heterogeneity of the distribution of pieces of mass in the pressed blanks. When pressing pieces of a non-uniform mass of billets of rectangular cross section with a relative deformation of 30-60%, internal pores and even voids cannot be completely eliminated. In the process of rolling such billets, defects are formed on the sheets in the form of unformed sections (voids and friability).

 The closest in technical essence and the achieved effect to the proposed device is a device that includes mixing rollers for the preparation of bundles and rollers for the preparation of abrasive mass, as well as a press for obtaining rectangular billets from lump mass [4].

 The disadvantage of this method is the low quality of pressed billets and sheets obtained from them.

 The task of the invention is to eliminate these drawbacks, namely increasing the uniformity of the distribution of components in the workpieces from abrasive mass, improving the quality of the workpieces and sheets obtained from them.

 The presented task is achieved by the fact that in the known method of producing blanks from a volcanic abrasive mass, comprising preparing on a rolls a volcanic binder, and then the finished mass, and pressing rectangular pieces from the lump mass, according to the invention, when lump mass is pressed, semifinished products of predominantly rectangular cross section are pressed through the slits of the matrix and lay them on top of each other. In this case, the semi-finished products are installed on a moving substrate, the output speeds of the semi-finished products and the substrate are equal. Semi-finished products are superimposed on each other in height, forming a rectangular blank with a wedge-shaped front end.

 The process of pressing rectangular pieces from a lumpy mass by molding in a mold differs significantly from the pressing process by squeezing a matrix of semi-finished products of rectangular section from the mass through slots. When extruding in the mass, a stress state with high hydrostatic pressure and a deformed state with intense shears are created, which contributes to the complete elimination of internal pores and voids in the semi-finished products obtained by extrusion. A rectangular blank with a wedge-shaped end formed from semi-finished products is of high quality. Sheets rolled from such blanks will not have defects in the form of unformed sections.

 The task in the proposed device is achieved by the fact that in the device for producing blanks from volcanic abrasive mass, containing rollers for rolling the volcanic binder and abrasive mass, a press is equipped with a horizontally mounted mold with a horizontal container and a matrix with rectangular slots. The device is also provided with a substrate in the form of a conveyor mounted in front of the matrix.

 The method is as follows. A volcanic ligament is prepared on mixing rollers; an abrasive lump is prepared on other mixing rollers. This mass is fed to the press, square semifinished products are squeezed out through the slits of the matrix and superimposed on top of each other. When the semi-finished products are superimposed on each other, a wedge-shaped front end is formed. The lower semi-finished product is placed on a moving substrate, which is moved with the speed of exit of the semi-finished products from the matrix. A finished workpiece with a wedge-shaped front end is used to roll the sheet on free-standing calendars or on calendars of flow-mechanized lines, including successively arranged calendars.

 The proposed device is illustrated in the drawing.

 The device contains rollers for the preparation of lump volcanic ligaments (not shown), rollers for the preparation of abrasive lump mass (not shown). The mold of the press contains a rectangular container 1, inside of which a punch 2 with a press washer 3 is installed, and a matrix 4. The matrix 4 has horizontal slots 5 of a rectangular section. In the upper part of the mold, a loading device is installed 6. In front of the matrix, a substrate 7 is made, made in the form of a conveyor.

 A device for producing workpieces from abrasive volcanic mass works as follows.

 The lump mass is loaded by means of a loading device 6 into the container 1 (arrow A). With the help of a punch 2 and a press washer 3, the volcanic mass 8 is squeezed out through the slots 5 of the matrix 4 (in the direction of arrow B) and the resulting rectangular semi-finished products 7 are laid on the substrate - conveyor 10, forming a layered blank 9.

 To implement the proposed method, an experimental device for extruding layered semi-finished products with a height of 10 mm and a width of 200 mm was designed and manufactured. Of these, blanks were formed with a height of 40 mm and a width of 200 mm and a length of 600 mm. From the blanks obtained by this method, sheets with a height of 20, 15 and 10 mm were rolled on a two-roll calender with a roll diameter of 300 mm. All rolled sheets had a high-quality surface; no friable or unformed sections were observed on the sheets.

 The proposed method and device is most suitable for use in the production of grinding and polishing abrasive wheels on a vulcanite bond with a diameter of 80 to 600 mm and a height of 5 to 50 mm.

Sources of information
1. Gurevich A.S. Equipment for the production of abrasive tools. - M.: Mechanical Engineering, 1964.-S. 182.

 2. There. - S. 182-184, FIG. 98.

 3. Technological instructions for the manufacture of volcanic and flexible polishing wheels. South Ural Central Scientific and Technical Research Institute, 1970 .-- S. 26-41.

 4. Pat. RF N 2108227, B 24 D 18/00, 03/25/97.

Claims (6)

 1. A method of producing blanks from volcanic abrasive mass, comprising preparing bundles, finished mass on the rollers, forming a blank and then pressing it, characterized in that a matrix with slots is used, and the blank is formed by extruding the finished mass through matrix slots and laying extruded semi-finished products Each other.  2. The method according to claim 1, characterized in that through the slits of the matrix extruded semi-finished products of rectangular cross section.  3. The method according to claim 1, characterized in that they use a substrate on which the semi-finished products are laid, while the specified substrate is moved with the exit speed of the extruded semi-finished products.  4. The method according to claim 2 or 3, characterized in that the semi-finished products are stacked on top of each other from the condition of forming a rectangular blank with a wedge-shaped front end.  5. A device for producing blanks from a volcanic abrasive mass, containing rollers for rolling the volcanic binder and abrasive mass and a press, characterized in that it is provided with a horizontally mounted mold located on the press and made in the form of a rectangular container, and a matrix with rectangular horizontally located slots placed one above the other.  6. The device according to claim 5, characterized in that it is provided with a substrate made in the form of a conveyor mounted in front of the matrix.