SU812403A1 - Shaft forging method - Google Patents

Description

(54) METHOD OF FORGING SHAFTS

I

The invention relates to the processing of metals by pressure, in particular to the technology of producing free forging shafts at Peres.

There is a known method of forging shafts on combined die heads, which includes the operations of feeding the workpiece to the tool, crimping it by applying additional forces to the side surface of the main and symmetrical with respect to the plane of the main force, and turning the workpiece after each reduction 1.

This method does not allow to obtain products of sufficiently high quality due to the constant position of zones of hindered deformation arising in places where additional efforts are made in the process of single reduction.

The purpose of the invention is to improve the quality of the products obtained by improving the study of the structure of the metal of the workpiece.

In order to achieve this goal in the method of forging shafts, including the steps of feeding the machined element to the tool, compressing it by applying additional forces to the side surface of the main body to the symmetric relative to the plane of application of the main force, in the process of each anniversary, the direction of application of additional forces is alternately changed efforts ranging from 90 to 1-2 °.

FIG. 1 shows the initial stage of reduction; in fig. .2 - intermediate stage; in fig. 3 - the final step.

The method is carried out as follows.

Claims (2)

The workpiece 1 is placed between instrumental 2 - 4 (see Fig. 1), after which the main ROSN and additional forces are applied to the workpiece i from the side of each tool; in the process of single reduction, tools 3 and 4 are rotated tangentially to the perimeter billet 1 relative to the axis of drawing in the direction of the tool 2. The rotation is carried out to the maximum possible approximation of tools 3 and 4, which is limited by the size of the workpiece and the possibility of its deforming without failure between tools 3 and 4. Next, tools 3 and .4 return to their original position. In the process of turning tools 3 and 4 of the zone of hindered deformation, arising in the places of application of additional us / sh, move along the perimeter of the workpiece in the direction to the upper structure. As a result, the non-uniformity of deformation during a single compression, and, consequently, the total non-uniformity of deformation over the entire forging period, is reduced. Each compression starts when the application is included; force relative to the plane of application of the main force a equal to 90 °. This position of the tool 2 - 4 corresponds to the case of forging the workpiece with flat dies, which ensure the maximum possible in the center of the workpiece. largest strain. If the angle a is more than 90 °, then tools 3 and 4 in the vertically transverse plane form two conjugate triangles that are in contact with the workpiece along verles. As a result of deformation by tool 3 and 4 in such a position on the surface of the deformable workpiece, hacks are possible. As deformed in. In the process of a single reduction, the angle a decreases a by 90 °, causing a decrease in the amount of deformation in the center. preforms and their development in the surface layers of the preform. Consequently, in the process of each reduction, starting from the center of the workpiece, the structure of the metal of the workpiece, practically the entire volume of the deformation zone, is worked out. The change in the direction of the application of additional forces relative to the plane of application of the main force is carried out depending on the diameter of the workpiece to an angle a. As the diameter of the workpiece decreases, the angle a decreases. And in the limiting case, at a 0 °, the workpiece may fall through between tool 3 and 4. Therefore, the minimum value of the angle ssu should be 1-2 °. Example. Lead blanks of the same heat are forged at room temperature from a diameter of 70 mm to a diameter of 30 mm. The forging is carried out by feeding the machined shaft to the tool, crimping by applying additional force to the side surface of the shaft and symmetrically with respect to the plane of application of the main force, additional forces and turning points after each crimping. In this case, in three cases, in the process of each reduction, the direction of application of additional forces relative to the plane of application of the main force is constant and the angles between the direction of application of the main and additional forces are respectively 90 °, a ,. 55 ° and about: t, 45 °. In the fourth case, during each reduction 4, the direction of application of external forces is alternately changed relative to the plane of force of the main force from hell 90 ° to -1-2 ° (with a workpiece diameter of 30 mm). Further, from the central part of the forged hedges, five samples are made in the longitudinal direction, which are subjected to stretching. The test results are presented in tabitsa. It follows from the table that the ductility during tensile tests of lead samples is higher in the case of EU; in the process of each reduction, the direction of application of additional forces is alternately changed relative to the plane of application of the main force in the range from 90 to 1-2 °. Increased ductility in this case is associated with an improvement in the quality of the material structure. Using the proposed method of forging shafts, especially when forging low-plastic grades of steel and alloys, provides for obtaining a more dense metal and a uniform shaft structure, improving the mechanical properties of the shaft metal, increasing labor productivity when forging shafts. The method of forging the shafts, which includes the operations of feeding the workpiece into the tool, crimping it by applying additional forces to the lateral surface of the main and symmetrical with respect to the plane of the main force, as well as turning the workpiece after each reduction, in order to increase the quality of the products obtained by improving the study of the structure of the metal of the billet in the process of each reduction, the direction of application of additional efforts alternately change applying no ground plane force between 90 ° and up to 1-2 °. Sources of information taken into account in the examination 1. P. Kamnev. Improvement of forging large forgings. L., Mechanical Engineering, 1975, p. 344.