SU772782A1 - Method of grinding with belt - Google Patents

Description

i

This invention relates to metalworking and concerns the problem of preventing wear of contact elements of tape and machine tools.

The known method of belt grinding of metal parts is when the abrasive tape is pressed against the workpiece by a contact element, which is informed by movement, and to increase the efficiency of the process and reduce wear of the contact element, the treatment is carried out using coolant-free liquids (coolant) {jlj.

However, with the known method of grinding, the contact elements nevertheless rather quickly accumulate, and unevenly along the working surface, which forces them to spend considerable funds on their finishing, which, in particular, is carried out mechanically by the abrasive tape itself.

However, in this case, a scarce hard alloy is used, from which contact elements are usually made. In addition, the restoration of grinding carbide contact elements requires considerable time, special tapes, devices, etc.

The purpose of the invention is the restoration of worn contact elements by using electrolytic implantation of the contact element.

This goal is achieved by the fact that electrolytic metal deposition is carried out directly in the process of belt grinding of parts, for which the contact element is supplied with a negative electrical potency, is positive on the workpiece, and electrolyte containing salts of the deposited metal is used as the coolant.

FIG. 1, the proposed method is illustrated in the plane of rotation of the tape in FIG. 2 is a view A of FIG. L

20 The grinding of part 1 is carried out with an abrasive tape 2, the envelope of the guide rollers 3, the drive and tension pulley 4 and the contact element 5. Part 1 is fixed in the tool

25 6, and the plunging serves the contact element 5 (in the direction of the arrow

W).

The reverse scheme is also possible when the contact element 5 is stationary, and 30 to the tape presses the workpiece 1. Processing is carried out according to the copying method, when the working surface of the contact element is equidistant processed by the thickness of the tape, or according to the method of running-in, when the parts report forming motion: .

The abrasive tape is reported to rotate at the rate of the encryption of Y, and if necessary, the transverse movements of S (Fig. 2).

In the treatment area using a special nozzle 7 serves a stream of Q mamaochno-cooled liquid containing salts of the deposited metal. Electrolytes are used as coolant; water based fluids. The electrolyte composition is accepted according to recommendations known from the technical literature, or selected (refined) experimentally, depending on the material being processed, the contact element material, grinding conditions that affect the wear rate of the contact element, etc.

Chrome lining is currently considered the most wear resistant coating, which is recommended as a specific example to prevent wear of contact elements. In this case, chromic anhydride and trivalent chromium, caustic soda, and other components are included in the electrolyte (COX) composition in accordance with known recommendations.

In the process of grinding, a positive potential (+) is applied to the workpiece, and a negative (-) potential is applied to the contact element.

In the process of grinding the workpiece, the moving abrasive belt gradually wears out the contact element, as if to produce its operation for cleaning the electrochemical tetrahromat (cold) chrome plating.

Under the action of the electric field formed between the work piece and the contact element, chromium from the electrolyte is deposited on the wear areas of the contact element. At the same time, the areas of the contact element that are not resistant, i.e. the tape is not cleaned, practically and is not chromed. Thus, if any part of the contact element wears out faster, then it is faster and restored. In this case, the shape of the contact element is not lost.

The rate of electrolytic deposition is assumed to be equal to or greater than the rate of wear of the contact element. In the latter case, the potentials are applied to the contact element and the part periodically, for example, based on the results of measuring the accuracy of processing.

The magnitude of the speed of chromium plating is chosen experimentally with the usual methods (i.e., selection of electrolyte density, current density, etc.). If the part is polished with a narrow belt with transverse movements S, then the chrome plating process is carried out mainly with the help of an electrolyte filling the gap a (phi 2) 5 between the part and the contact element, and if the treatment is performed with a wide belt equal to the width of the part, The basis of the abrasive belt is made of a porous material (fabric), 0 which is well impregnated with electrolyte, or, otherwise (for example, nylon tapes), a plurality of holes are made in the tape (the process of grinding and polishing is intensified during echoing). and an account of the abrasive coverage of the abrasive).

The achieved positive effect (elimination of time for fine-tuning contact elements, increasing the productivity and accuracy of grinding due to this) depends on the specific processing conditions (type of material being processed, modes, etc.).

In addition, contact elements can be made from ordinary structural steels instead of expensive solid alloys.

 the invention

0 The method of grinding with a tape, the size of which is less than half the width of the copier that presses it, which is set to reciprocate through the treatment area, with irrigation of the working

. Sources, characterized in that 5, in order to prevent wear of the contact element, the grinding process is carried out in the mode of electrochemical restoration of the copier, for which purpose

0 The electrolyte and the copier and the product are included in the circuit of the direct current source.

Sources of information taken into account in the examination

55 1. USSR author's certificate 117101, cl. B 23 P 1/10, 1958.

Claims (1)

Claim 4S A method of grinding with a tape, the size of which is less than half the width of the copier pressing it, which sets the reciprocating movement along the processing zone, with irrigation of the working medium, characterized in that, in order to prevent wear of the contact element, the grinding process is carried out in the mode of electrochemical restoration of the copier, for whereby electrolyte is used as the working medium, and the copier and product are included in the DC source circuit.