SU1761450A1 - Method for pressure strain hardening of crankshaft fillets - Google Patents

Abstract

Use, metal forming, surface hardening of machined surfaces. SUMMARY OF THE INVENTION: during hardening of crankshaft fillets, the deformation forces are applied to the heel of the crankshaft RZLOV, deformation forces are applied to the fillets on the half-arc of the circumference of the neck of the weights from the side of the weights, and the cores are laid by the sheets. necks. Then shake the beats of each root cervix and determine the neck that has the maximum beating beyond the outlet. The additional force of deformation-propagation of the galtol.1 of the above-mentioned root collar, having a maximal runout, was measured at half of the arc of its circumference from the side of the adjacent connecting rod, in the plane of the Yuroy, the beating was measured. 3 il., 1 gab.

Description

The invention relates to mechanical engineering, mainly to engine building, in particular to crankshafts of internal combustion engines that are under heavy loads.

The known method of hardening shaft fillers, in which, in order to increase the fatigue strength of the shaft and ensure the correct geometrical shape, surface plastic deformation is performed with a constant force in the area of the shaft concavity (ed. St. USSR No. 494413).

However, this method is not acceptable in such a way to strengthen crankshaft fillets. For example, a five-bearing eight-cylinder GAZ-53 engine has five main and four crankpins.

and these are 18 engines, Shatuin-e shake are located at an angle of 90 °

There is a method of hardening the crankshaft fillets by plastic deforming by wrapping the leggels with zeros. Odnogfemv-but in one turn of the hall run around the rod of the connecting rod and indigenous necks (Donetsk V.Buntos VN and others. Increasing the resource by technical methods. Mashinostroenie v., 1978, p.44)

However, with the known method, along with an increase in ycTfsiocTHon of the shaft strength, the specificity of splicing on the bearing surfaces of the necks and joint is increased, as the lintels have a smaller diameter than the same nack. are below the surface of their winter about 20% of their surface and i e in (c

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gas pressure loads, which requires an increase in the length of the necks to reduce the specific loads.

Increasing the length of the neck and: going: increasing the size and weight of the engine by 10-15%. Increasing the specific loads, if not lengthening the neck, leads to fatigue damage to the liners. In addition, after running of the fillets, the beating of the main journals reaches 0.2 mm, which additionally requires grinding the main journals.

The purpose of the invention is to improve the quality of processing by increasing the fatigue strength and the accuracy of the shape of the shaft being machined and to narrow the operational specific loads on the bearings by maintaining the areas of the bearing surfaces.

The goal is achieved by the method of strengthening the crankshaft fillets by surface plastic deformation by applying deformation forces to the fillets of the main and connecting rod journals, according to the invention, the deformation forces are applied to the fillets on the half of the arc of the rod of the connecting rod necks from the counterweights, and the root ones the crank neck, then the beating of each root neck is measured, the neck having the maximum beating beyond the tolerance is determined, and additional force is applied It is not distorted to the fillet of the root collar, which has the maximum beating, at half the arc of its circumference from the side of the adjacent crank neck, in the plane of which the maximum beating is measured.

When hardening by the proposed method, the deformation is one-sided and is directed in the direction opposite to the deformation of the shaft axis from hardening of the connecting rod necks. The beating of the shaft is reduced two times. If necessary, if the beats of the vals are higher than the allowable, in the same zones additional deformation is present to the fillet with the maximum beating. In this way, the shaft runout can be brought up to the requirements of the drawing, eliminating the need for further shaft polishing to eliminate the beat.

FIG. Figure 1 shows schematically a general view of the crankshaft and the zone of application of deformation to the crank shaft haptels along an arc of 90 to 270 °; in fig. 2 - section A - A in FIG. 1 and the zone of application of the deformation to the fillet of the crank neck in an arc from 90 to 270 °; in fig. 3 shows a section BB in FIG. 2 and the zone of application of the deformation to the fillet of the root collar in an arc from 270 ° to 90 °,

In the drawings, the following notation is accepted: 1 — main crankshaft necks, 2 — rollers, 3 — crank necks, 4 — zones of the crank of the conrod neck, 5 — zones of the main necks, 6 — hour indicator, 7 — counterweights, 8 - shaft axis.

The method is carried out as follows.

Hardening crankshaft fillets

engine YMZ. made of 50G steel and ground up to 2 repair size and having a beat of 0.01 mm, was carried out on a screw-cutting lathe at a rotation frequency of 10 rpm.

The Galtels 4 and 5 were driven around by a hard-alloy roller 2 with a radius of 6 mm on the half-arc of the connecting rod connecting rod 4 on the side of counterweights 7, and the main bearing 5 on the side of connecting rod neck. The run-in was made by one fillet - one roller with a force of 350-400 kgf to a depth of 1 - I.5 mm. The beating of each root neck is then measured. using indicator 6. Determine the neck with the maximum runout. This is a 3-root

neck in the plane of the 2nd crank neck - beating is 0.09 mm. This is the maximum heartbeat that goes beyond tolerance. An additional deformation force is applied to the 3rd root neck on

half of the arc of its circumference from the side of the adjacent crank neck 2, in the plane of which the maximum runout is measured. With additional effort we bring

the beating of this neck to 0.03 mm with the help of indications of the indicator 6, which controls the beating in the process of deformation.

Comparative hardening of crankshaft fillets was carried out.

on the proposed and known methods (prototype). The results are summarized s table. The table shows that the fatigue strength of crankshafts, fillets which are strengthened by the proposed method,

increased by 13%.

The supporting surface of the necks is more than 20%, which reduces the specific loadings /. reduces fatigue damage to liners.

The beating of the shafts according to the proposed method is an order of magnitude less than that known, grinding is excluded.

Reduced non-parallelism of the axles of the connecting rod journals relative to the axis of the main bearings.

5 2 times, which reduces the distortion of the piston to the cylinder by 0.05-0.08 mm.

The formula and the phrase about 8

The method of hardening of the fillets of the crankshaft as a result of the plastic plastic deformer by the link through the use of force

deformation of main and crank journals to galtels, characterized in that, for the purpose of elevated, I saw the treatment of 3d by increasing the fatigue strength and shape accuracy of the shaft and lowering the specific bearing loads by maintaining the bearing surface areas; to the gal gel m on the half arc of the circumference of the connecting rod necks from the side

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counterbalances, and the main ones - from the tail of the tail necks, then the beating is measured each (the neck neck, the neck is determined, I, and j; / io the maximum beating outgoing 3J tolerance limits, and The shape of the root to the .o ner. i root neck with the maximum beating is half the arc of its circumference from the side of the receiving neck and aTVrfH i, the neck, in the plane of which the syringe is measured.

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Claims (1)

Claim The method of hardening the crankshaft fillets by surface plastic deformation by applying deformation forces to the fillets of the main and connecting rod necks, characterized in that, in order to improve the quality of processing by increasing the fatigue strength and accuracy of the truss of the machined 5 shaft and reducing the operational specific load on the bearings by maintaining the areas of the supporting surfaces, the deformation forces are applied to the fillets on a half-arc of the circumference of the connecting rod journals on the side of the counterweights, and data from the side of the connecting rod necks, then measure the runout of each root neck, determine the neck that has the maximum runout that is outside the tolerance, and apply an additional deformation force to the fillet of the root neck having the maximum runout, on half of the arc of its circumference from the side of the adjacent connecting rod neck, in the plane of which the maximum runout is measured. I №№ pp Fatigue strength, 2 kg / mm Supporting surface,% Arc of a circle. Runout mm Non-parallel axis of the connecting rod relative to the root neck, mm ί The proposed method ί 1 18.9 100 '90-270 0,03 0.010 | 2 18.8 100 90-270 0,025 0.10 3 18.7 100 90-270 0,035 0.010 4 - 18.3 100 110-250 0.045 0.015 5 18.1 100 120-230 0.05 0.017 • The known method {prototype ' 1 16.0 80 360 0.25 0.30 2 16.1 80 360 0.30 0,035 3 16.1 80 360 0.20 0,025