RU2754628C1 - Device for fixing axisymmetric parts during their thermal power processing - Google Patents

Abstract

FIELD: fixing devices.

SUBSTANCE: invention relates to a device for fixing axisymmetric parts during their thermal power processing. The device is made in the form of a slipway with a body having a cavity that is filled with filler and closed on both sides with threaded plugs and contains mechanisms for fixing parts. The body of the slipway is made of a cylindrical shape, on the ends of which two covers are rigidly fixed, and it is ribbed along the outer diameter with ribs in the form of rings with a step equal to six of its diameters. At least six slots for fixing parts are cut out on the ribs evenly spaced along the diameters of the ribs, while one mechanism for fixing parts is made in the form of a rigid center, and the other mechanism for fixing parts is made in the form of a center that can be axially moved, and both of these mechanisms are installed on the two specified covers. On both sides of the grooves, two replaceable plates are fixed on the ribs, which are made with slots, or replaceable locking washers are installed on the ribs in the groove area.

EFFECT: improving the design of the device to ensure increased quality and performance of thermal power processing.

1 cl, 6 dwg

Description

The invention relates to mechanical engineering technology, and more specifically to devices for thermal power processing of low-rigid axisymmetric parts of the "shaft" type.

Known device for thermal power processing of shafts of low rigidity, including a slipway, which is made in the form of a pipe made of metal with a coefficient of linear expansion greater than that of the product. The device for the same purpose to the claimed invention, selected as a prototype, is a device for thermal power treatment containing a multilayer prefabricated sectional slipway made in the form of a pipe made of a material with a coefficient of linear expansion greater than that of a product, the internal space of which is filled with a sand filler with cast iron shavings, radiators with radial grooves installed on the outer surface of the product along its entire length, thrust bearing caps and spherical feet for rigid fixation of the product on both sides relative to the ends of the slipway [1].

The disadvantage of this device is the complexity of the design due to the presence of a prefabricated multilayer slipway and a large number of radiators in the design, as well as harmful working conditions, since when the device is cooled in oil, the filler of the slipway is impregnated with oil, and the rate of its cooling is very low, therefore, oil burns out and, as a result, the production areas are smoke-filled.

The closest device for the same purpose to the claimed invention, selected as a prototype, is a device for thermal power treatment containing a slipway in the form of two pipes with a filler, made of a material with a coefficient of linear expansion greater than that of the part, a threaded mechanism for fixing parts at both ends in the form of two washers-spheres and two nuts for force locking, the pipes of the slipway are screwed into each other, each of them is made with a parabolic profile, the mechanisms for fixing the parts are placed along the perimeter of the slipway, and the filler is in the central part of the slipway in a cavity closed on both sides threaded plugs [2].

The disadvantage of this device is its limited technological capabilities. The workpiece only experiences tensile deformations and during this processing there is an uneven permanent deformation along the entire length of the workpiece, which leads to warping of the finished product, loss of accuracy for the entire period of operation.

The task to be solved by the claimed invention is to improve the quality of manufacturing of low-rigid axisymmetric parts with the achievement of the following results: increasing the stability of dimensions and shape of axisymmetric low-rigid parts by eliminating the direction of axial residual stresses, due to a uniform loading scheme; elimination of technological heredity due to the restructuring of the material texture, which leads to a more uniform distribution of residual stresses along the length of the part. Improvement of the design of the device for thermal power treatment, provides an increase in the quality and productivity of thermal power treatment.

This problem is solved by the fact that the body of the slipway is made of a cylindrical shape, at the ends of which two covers are rigidly fixed and ribbed along the outer diameter with ribs in the form of rings with a pitch. The pitch of the rings should be equal to six of its diameters, with at least six grooves evenly spaced along the diameters of the ribs cut out on the ribs to fix the parts. One mechanism for fixing parts is made in the form of a rigid center, and the other mechanism for fixing parts is made in the form of a center that can be axially displaced. Both of these mechanisms are installed on the two indicated covers. On both sides of the grooves on the ribs, two replaceable plates are fixed, which are made with slots or replaceable lock washers are installed on the ribs in the area of the grooves.

Execution of the slipway monolithic allows to exclude plastic deformation in the threaded connection and to increase the service life of the installation.

Placement of part holders along the perimeter of annular ribs without preliminary power loading excludes axial force locking of parts.

The distribution of the force load evenly along the length of the part with division into equal deformation zones ensures uniform deformation of the part along the length.

Fixation of the blanks in the grooved grooves of the rings provides an additional heat outflow, which excludes the direction of the thermal deformation of the part. The choice of the design of the grippers in the form of two interchangeable locking plates allows fixing parts of various diameters in a wide range.

The invention is illustrated in the drawings, where FIG. 1 shows a diagram of the machining of a part. FIG. 2 shows a general view of the device for TCO, FIG. 3 shows view A of FIG. 2, in - fig. 4 shows a section b-b of Fig. 2, FIG. 5 shows a section D-D of FIG. 2. In FIG. 6 shows a section b-b of FIG. 5.

Parts 1, with pre-machined annular grooves, are installed in the grooves 2 of the annular ribs 4 of the slipway 5. Inside the slipway 5 there is a cavity 6, into which the filler 7 (sand, cast iron shot) is filled. The cavity 6 is closed on both sides with threaded plugs 8. The coefficient of linear expansion of the slipway 6 is greater than that of parts 1. Two covers 9 are fixed on the slipway 5 on both sides of the slipway 5. In the covers 9 there are two centers 10 and 11. The center 10 is adjustable, and center 11 is hard. On the periphery of the annular ribs 4 on both sides of the grooves 2 are attached two replaceable plates 12. The grooves of the plates 12 are made smaller than the grooves on the ribs.

The device for TCO works as follows. After fixing the parts 1 in the grooves 2 of the annular ribs 4 of the slipway 5, the latter has a cavity 6, which is filled with filler 7 (sand, cast iron shot). The cavity 6 is closed on both sides by threaded plugs 8. At the ends of the slipway body 5, on both sides of it, two covers 9 are attached, in which stoppers 10 and 11 are fixed. The latter provide fixation of the part during thermal power processing. Further, the slipway 5 with installed parts 1 is heated in a shaft furnace to the working temperatures of quenching or tempering according to the standard heat treatment technology. Due to the greater or lesser coefficient of linear expansion or contraction of the stock of the material of the stock 5, greater or less than the coefficient of linear expansion or contraction of part 1, axial deformation of stretching or compression of parts 1 occurs. than parts 1, which allows them to maintain their stress state throughout the entire processing cycle. This device allows for axial tensile deformation or compression of the part. For this, plates 12 are attached to the ribs 4 on each side. To expand the range of the diameter of the workpieces on the ribs 4, on each side of the grooves 2, plates 12 are attached with smaller dimensions than the grooves on the ribs 4. The use of this device allows you to obtain uniform plastic deformation of the material parts along its entire length and, accordingly, stabilize residual stresses in the entire volume of the part, and, accordingly, stabilize the geometric parameters of the part, expand the technological capabilities of the process and simplify the design of the device for thermal power treatment.

Bibliography

1.SU 1708884 A1, 30.01.1992.

2. RU 2381282 С21, 10.02.2010

Claims (1)

A device for fixing axisymmetric parts during their thermal power processing, made in the form of a slip with a body with a cavity filled with filler and closed on both sides with threaded plugs, and containing mechanisms for fixing parts, characterized in that the body of the slip is cylindrical, at the ends of which it is rigid two covers are fixed, and ribbed along the outer diameter with ribs in the form of rings with a pitch equal to six of its diameters, while at least six grooves evenly spaced along the rib diameters are cut out on the ribs for fixing parts, while one mechanism for fixing parts is made in the form of a rigid center , and the other mechanism for fixing the parts is made in the form of a center that has the possibility of axial movement, and both of these mechanisms are installed on the two indicated covers, and on both sides of the grooves on the ribs two replaceable plates are fixed, which are made with slots, or on the ribs in the zone of the grooves are installed replaceable lock washers.

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