RU234997U1 - CRANKSHAFT CONNECTING ROD - Google Patents

Abstract

The utility model includes a housing (1), wherein an insert (2) made in a ring-shaped form is installed inside the housing. The insert (2) of the connecting rod is made of silicon carbide with a thickness of at least 2.75 mm. The technical result of the claimed utility model is an increase in the wear resistance of the insert. 1 ill.

Description

AREA OF TECHNOLOGY

The utility model relates to the field of mechanical engineering, in particular to crankshaft connecting rods, and can be used in the designs of heavily loaded crankshaft connecting rods of automobile internal combustion engines, centrifugal, plunger pumps and compressors, as well as in other mechanisms that have a crank mechanism.

LEVEL OF TECHNOLOGY

The prior art discloses a thin-walled bearing insert for a crank mechanism, which includes a steel housing, an antifriction layer, a running-in coating, and end surfaces, wherein the cross-section of the steel housing is made to decrease monotonically from the axis of symmetry to the end surfaces (see SU 1809192).

The technical problem inherent in the given analogue is the complexity of the design and the complexity of the manufacturing process of the insert.

This technical problem is caused by the fact that the insert includes a steel body, an antifriction layer, a running-in coating, and end surfaces, while the cross-section of the steel body is made to decrease monotonically from the axis of symmetry to the end surfaces.

The closest analogue selected is a multilayer connecting rod bearing of the crankshaft connecting rod, which is a ring-shaped part, on the outer surface of which a plasma anti-corrosion bronze coating is applied, and on the inner surface an antifriction layer of lead-tin bronze with microadditives of nickel powders, zirconium oxide, aluminum oxide and cerium oxide, a barrier nickel layer, an antifriction layer based on a galvanic alloy of tin-antimony-copper, tin, and a running-in layer of a solid lubricating polymer coating based on molybdenum disulfide with fullerene (see RU 2813220) are applied.

The technical problem inherent in the given analogue is accelerated abrasive wear, fatigue chipping and destruction of the working layer in the form of local delamination of the material from the base.

This technical problem is caused by the fact that the insert is made in the form of a multi-layer structure.

DISCLOSURE OF THE ESSENCE

The technical result of the claimed utility model is an increase in the wear resistance of the liner.

The stated technical result is achieved by the design of the crankshaft connecting rod, which includes a housing, with a ring-shaped insert installed inside the housing.

The connecting rod insert is made of silicon carbide with a thickness of at least 2.75 mm.

A distinctive feature of the silicon carbide insert is the high hardness of the material, which allows to minimize wear of friction units, increase the reliability of the insert itself and the structure, which includes the insert, and also increase its service life.

The service life of mechanisms with parts made of silicon carbide is higher than that of tool steels and graphites and, on average, 1.5-2 times higher than that of hard alloys.

Based on the results of the tests and calculations, it was established that it is most advisable to make the liner with a thickness of at least 2.75 mm, since a smaller thickness does not provide a significant increase in the wear resistance of the liner, since when using the liner in an environment with a high abrasive content, rapid wear and a decrease in the thickness of the liner may occur, and therefore, it is advisable to make it with a thickness that allows the liner to be used for a long period without replacing it, which will increase the service life of the structure as a whole.

Silicon carbide has high wear resistance, chemical resistance and high mechanical characteristics, therefore, the production of the insert from the specified material contributes to the achievement of the declared technical result.

In its design, the crankshaft connecting rod can be composite and include an upper part with a connecting rod rod and a lower part, while the liner can also be composite and consist of two half rings, one of which is installed in the upper part of the connecting rod, and the other in the lower part of the connecting rod.

BRIEF DESCRIPTION OF DRAWINGS

The claimed utility model is illustrated by an illustration, where the following structural elements of the crankshaft connecting rod are designated by positions:

pos. 1 - crankshaft connecting rod housing;

pos. 1.1 - upper part of the crankshaft housing;

pos. 1.2 - lower part of the crankshaft housing;

pos. 2 - insert;

pos. 2.1 - half ring of the insert.

IMPLEMENTATION OF A UTILITY MODEL

The claimed utility model is implemented as follows.

The crankshaft connecting rod includes a housing 1, wherein an insert 2 made of an annular shape is installed inside the housing. The insert 2 of the connecting rod is made of silicon carbide with a thickness of at least 2.75 mm.

The body can be made as a single integral structure, or it can be composite and include the upper part 1.1 with the connecting rod and the lower part 1.2, connected to each other using fasteners, such as bolts or studs.

Insert 2 can also be made as a composite of two half rings 2.1, which are installed in the upper part 1.1 of the housing and the lower part 1.2, respectively.

The crankshaft connecting rod insert is made of high-tech composite material based on carbon and silicon - silicon carbide. The material has high wear resistance and high mechanical characteristics.

The silicon carbide insert can be produced using reactive solid-phase or liquid-phase sintering technology. During the production process, the initial blank, obtained by pressing a mixture of silicon carbide and graphite powders, is impregnated with silicon melt, after which the sintered blank is subjected to mechanical processing.

The main advantage of this material is its very high wear resistance under severe conditions of abrasive wear and elevated temperatures, ensured by a combination of high hardness and high thermal conductivity.

The use of silicon carbide allows to increase the wear resistance of the liner.

During assembly, the liner is installed in the crankshaft connecting rod housing in the bearing hole and can be secured in any acceptable way, for example, with locks or some special fasteners.

When a crankshaft connecting rod is used in a piece of equipment, such as a plunger pump, the connecting rod bushing contacts a bearing that is mounted on the crankshaft.

The stated solution can be used in any machine that uses a crank mechanism.

Claims (1)

A crankshaft connecting rod comprising a housing, wherein a ring-shaped insert is installed inside the housing, characterized in that the insert is made of silicon carbide with a thickness of at least 2.75 mm.