RU1794685C - Device for crushing solid material plates - Google Patents

Abstract

Usage: processing of stones, superhard materials. SUMMARY OF THE INVENTION: A plate and adjacent malleable elements are placed in a confined space limited by rigid elements to which a load is applied. 2 s.p., f-ly, 3 ill.

Description

The invention relates to the processing of stones and the like. materials and can be used in the manufacture of elements from plates by notching and breaking them. The field of application of the invention, in particular, encompasses a class of wafers made of superhard materials based on diamond, cubic boron nitride, boron carbide, etc., which require considerable processing costs due to their high hardness and stiffness.

A known method of cutting stones by splitting is according to which an incision is made at the object and an impact load is applied from the side opposite to the incision. The application of the method is limited to the class of large-sized objects with high inertia at the depth of the notches - a few centimeters.

A method for separating notched plates is known, according to which a pre-notched plate is placed between two flexible plates to which a load is applied by means of pressure rolls. The disadvantages of the method include the fact that the used loading scheme, due to the relatively high flexibility of the flexible elements, cannot provide load levels sufficient to break the notched plates with high erect stiffness.

The closest in technical essence to the claimed invention is a method of breaking plates, according to which a pre-cut plate is placed between pliable elements: an elastic base and a sheet of flexible material, a load is applied to the latter by means of a spring roller. This method has the same drawback as the analogue method. In addition, due to the need to position the pinch roller over each notch line, the length of the fracture process for long plates with a complex configuration with a large number of notches increases.

The purpose of the invention is to expand technological capabilities, as well as increase productivity by simultaneously breaking the plate along all notch lines.

In a method for breaking plates of solid materials, comprising

WITH

vj yu

Hv

0

00

ate

the joint of a plate previously cut along a predetermined contour between compliant elements to which a load is applied by means of rigid elements, the plate is further limited by lateral surfaces to form matrix cavities above the ends of the plate, in which compliant elements are placed having stiffness characteristics asymmetric with respect to the median plane of the plate and in at least one element - variables from the side surface to the center.

Moreover, the applied method is characterized in that at least one of the pliable elements is made of liquid, pasty or powder material.

In addition, on the lateral surface of the plate, a cavity is formed which communicates with the existing matrix cavity, into which an additional flexible element is placed.

From the position of resistance of materials in a plate with notches (stress concentrators) loaded with pressure e, the maximum stresses act.

tfmax a b he. (1)

where "B - stress concentration coefficient;

It is the nominal voltages or voltages in the sample without a hub. We can assume that the stress levels are proportional to the load d. Then, on the basis of (1), we have:

ОГТА «БР (2)

Plate breaking occurs when the stresses exceed the tensile strength of the plate material. From analysis (2), there are two possible ways to achieve the required Ohiax levels. At large values of Б B, breaking occurs at lower loads g and vice versa. However, increasing a B, as a rule, implies an increase in the depth of incision. This involves additional costs, especially when processing superhard materials. Therefore, it is preferable to increase the load levels at the minimum values of a B. At the same time, large loads will be required to break the plate with greater bending stiffness. Their ultimate value will be limited by the bearing capacity of rigid or pliable elements transmitting pressure to the plate. According to the prototype, pliable elements experience compression close to uniaxial. The ultimate load g for uniaxial compression cannot exceed

yield strength of the material of the compliant element - otherwise it will be extruded. It can be tentatively limited to g levels of B-10 MPa.

In the present invention, a malleable element is placed in a matrix cavity and is constrained in its deformation. This makes it possible to achieve loading pressures up to 1000 MPa and higher, up to the loss of strength of the rigid loading elements surrounding the matrix cavity.

The foregoing does not limit the scope of the invention to

plates with low bending stiffness, increases the productivity of the mesh due to the simultaneous breaking of the plate along all notch lines.

In FIG. 1 shows a deformed notched plate; in FIG. 2 - diagram

0 loads on the plate; in FIG. 3 is a diagram of power circuit elements.

The mechanism of interaction of features of the claimed population is as follows.

5 The initial prerequisite for fracture is bending deformation of the plate, in which the stretched fibers are on the notch side (Fig. 1). To carry out this type of deformation,

0 is a force loading circuit which causes bending moments of the corresponding sign in the plate. Consider, for example, a sufficient general scheme depicted in Fig. 2. The counterpropagating loads gi and d2 are asymmetrically distributed metrically relative to the median plane of the plate, but their resultant is zero. A variant is possible when an additional lateral load DZ is applied, which increases the hydrostatic component of the stress state and, as shown by experiments, improves the fracture quality for plates with high bending stiffness. Pressure gi, yes, dz

5 are transferred to the plate 1 by means of compliant elements 2, 3, 4 (FIG. 3), the configuration and (or) rigidity of which has asymmetry characteristic of the law of load distribution g (FIG. 2). Malleable

0 elements are placed in matrix cavities and subjected to the action of hard load elements 5, b, 7 (Fig. 3), closing the power circuit,

For the convenience of filling matrix cavities, liquid, paste-like or powder materials are used as malleable elements whenever possible. Moreover, in the last two states of materials, compositions with desired properties are easily obtained. Liquids like

other materials with zero or near-zero shear fluid are used, as a rule, in the form of thin interlayers, the thickness of which is comparable with the deformations of the plate.

Example 1. On a diamond-carbide plate with a diameter of 13.5 mm and a height of 3.5 mm, a diametrical incision with a cross section of 0.3 x 0.3 mm is pierced from the side of the hard alloy. In a cylindrical cavity with a diameter of 13.5 mm with a flat base sequentially placed: a rubber disk 1 mm high; the plate is notched up; graphite disk 3 mm high; a steel cylinder with a diameter of 13.5 mm with a working profile in the form of a cone with an angle of 150 °, turned upward. A pressure of 800 MPa was applied to the steel cylinder, after which the plate broke into two parts along the notch.

Example 2. Under the conditions of example 1, two, three or four diametrical cuts were machined on the plate, after which the plastic

5

0

it was broken along the cuts into four, six and eight parts, respectively, Example 3. Under the conditions of Example 1, the graphite disk was replaced with graphite powder at a filling height of 4 mm, thereby eliminating the preliminary operation of manufacturing a graphite disk.

Example 4 Under the conditions of Example 1, the rubber disc was replaced with a layer of liquid engine oil, which was applied by contacting the plate with a surface moistened with oil. At the same time, the cost of auxiliary material was reduced.

Example 5. Under the conditions of Example 1, the diameter of the cylindrical cavity and all cylindrical elements, with the exception of the plate, was increased to 20 mm. A graphite ring with a diameter of 20 mm and a height of 3.5 mm was placed in the cavity formed from the side surface of the plate. As a result, the quality of the fault surface was improved.

Claims (3)

SUMMARY OF THE INVENTION 1. A method for breaking plates of solid materials, comprising placing a plate previously cut along a predetermined contour between pliable elements, to which a load is applied by means of rigid elements, characterized in that, in order to expand technological capabilities, as well as increase productivity by simultaneously breaking plates along all notch lines, the plate is limited along the lateral surfaces with the formation of matrix cavities above the plate ends, in which accommodate pliable elements that have stiffness characteristics asymmetric with respect to the median plane and in at least one element - variables from the side surface to the center, 2. The method of pop. 1, wherein at least one of the pliable elements is made of a liquid, pasty or powdery material. 3. The method of claim 1, wherein so that on the side surface of the plate form communicating with existing an additional matrix cavity into which the compliant element is placed. Fi 2.2 Fig.Z