A design method for differentiating the roller generatrix of an extra-large double-row tapered roller bearing

Abstract

The present invention discloses a method for differential design of the roller generatrix of an extra-large double-row tapered roller bearing, which includes, when designing the bearing, after structural design and static strength check, performing finite element analysis to calculate the maximum contact stress borne by each row of rollers; after obtaining two contact stress values, while keeping the contact lengths of the two roller generatrices with the raceway of the ring in the same range of the total length of the raceway, determining the coefficient value in the logarithmic function of the bearing generatrix, and determining the size of the roller bulge amount through this coefficient value. The present invention calculates the convexity deformation amount of the roller by using logarithmic function formulas with different coefficient values, which can ensure that the deformation amounts of the double-row tapered roller bearing are consistent under different contact stress conditions, and control the contact lengths of the two roller generatrices with the raceway of the ring within the range of 85-90% of the total length of the raceway, which is beneficial to increasing the rotation stability and reliability of the bearing, thereby prolonging the service life of the bearing.

Description

Technical Field

[0001] The present invention belongs to the technical field of roller bearings, and in particular relates to a method for differentially designing roller generatrixes of an extra-large double-row tapered roller bearing. Background Art

[0002] Large bearings (such as those used in wind turbines) require strict precision control during the design, manufacturing, and assembly stages due to their large dimensions, heavy weight, and harsh operating conditions. Extra-large double-row tapered roller bearings are commonly used in wind power generation. When designing these bearings, a preliminary structural design is typically performed based on the loads and mounting dimensions. Static strength verification is then performed. If the safety factor fails to meet the requirements or is excessively high, the structural parameters are revised repeatedly until the safety factor reaches the desired target.

[0003] However, since the forces on the two rows of rollers of the bearing are very different during actual operation, the above-mentioned traditional structural design, in order to make the roller stress distribution reasonable, although considering the use of a logarithmic curve for the roller busbar, does not take into account the different forces and stresses on each row of rollers. If the same logarithmic function is used, the length of the stress contact between the busbar of each row of rollers and the busbar of the ring raceway will also be different, which may easily lead to problems such as reduced bearing rotation accuracy, poor bearing reliability and short bearing life. Summary of the Invention

[0004] In order to solve the above technical problems, the present invention provides a differentiated design method for the roller busbars of an extra-large double-row tapered roller bearing. After calculating the maximum contact stress borne by each row of rollers through finite element analysis, the K value in the logarithmic function is determined according to the contact stress, so that the contact length between the two rows of roller busbars and the ring raceway is controlled within the range of 85-90% of the total raceway length, which is beneficial to improving the stability and reliability of the bearing rotation and extending the life of the bearing.

[0005] The technical solution adopted by the present invention is: a differentiated design method for the roller busbar of an extra-large double-row tapered roller bearing, including, when designing the bearing, performing structural design and static strength verification, and then performing finite element analysis to calculate the maximum contact stress borne by each row of rollers; after obtaining the two contact stress values, while keeping the contact lengths of the two roller busbars and the ring raceway within the same range of the total raceway length, determining the coefficient value in the logarithmic function of the bearing busbar, and determining the size of the roller protrusion by this coefficient value.

[0006] The bearing generatrix logarithmic function formula is: ;

[0007] In the above formula, L weis the effective length of the roller, x represents the abscissa of the curve, i.e., the value of the contact stress, and P x represents the ordinate of the curve;

[0008] wherein, P x value is also the convexity deformation amount of the bearing roller. It can be known from the above formula that when the contact stress values of the two rows of rollers are different, if the convexity deformation amounts of the rollers are to be kept the same, the value of the coefficient K can be adjusted to achieve this.

[0009] The contact lengths of the two roller generatrices and the raceway of the ring are both controlled within the range of 85 - 90% of the total length of the raceway.

[0010] The beneficial effects of the present invention are as follows:

[0011] The present invention uses logarithmic function formulas with different coefficient values to calculate the convexity deformation amount of the rollers, which can ensure that the deformation amounts of the double-row tapered roller bearings are consistent under different contact stress conditions, and the contact lengths of the two roller generatrices and the raceway of the ring are both controlled within the range of 85 - 90% of the total length of the raceway, which is beneficial to increasing the rotation stability and reliability of the bearing, thereby prolonging the service life of the bearing. Specific Embodiments

[0012] The following further elaborates on the specific embodiments of the present invention.

[0013] A method for differential design of the generatrix of rollers of a super-large double-row tapered roller bearing includes, when designing the bearing, after structural design and static strength check, performing finite element analysis to calculate the maximum contact stress borne by each row of rollers; wherein, finite element analysis is to simulate the real physical system (geometry and load conditions) by using a mathematical approximation method, and by using simple and interacting elements (i.e., units), the real system with an infinite number of unknowns can be approximated with a finite number of unknowns. In actual work, CAD software (including Pro / ENGINEER, Unigraphics, SolidEdge, SolidWorks, IDEAS, Bentley, and AutoCAD, etc.) can be used for modeling, thereby performing finite element analysis;

[0014] After obtaining the two contact stress values, under the condition that the contact lengths of the two roller generatrices and the raceway of the ring are both controlled within the same range of the total length of the raceway, determine the coefficient value in the logarithmic function of the bearing generatrix, and determine the size of the roller convexity amount through this coefficient value; during the actual working stage of the bearing, the generatrix of the roller has a certain convex shape, and when the roller bears a load, the roller will produce a certain deformation. In order to make the deformation amounts of the two rows of rollers consistent under the condition of bearing loads, therefore, logarithmic functions with different coefficient values are needed to calculate their deformation amounts.

[0015] The bearing busbar logarithmic function formula is ;

[0016] In the above formula, L we is the effective length of the roller, x represents the abscissa of the logarithmic curve, that is, the value of the contact stress, and P x represents the ordinate of the logarithmic curve;

[0017] Among them, the value of P x is also the convexity deformation amount of the bearing roller. It can be seen from the above formula that when the contact stress values of the two rows of rollers are different, if the convexity deformation amounts of the rollers are to be kept the same, the coefficient K value can be adjusted to achieve it; specifically, when the stress value is larger, the K value is selected to be smaller, and when the stress value is smaller, the K value is selected to be larger. In this way, when designing the bearing, logarithmic function formulas with different K values can be selected for the two rows of rollers at different positions.

[0018] The contact lengths of the two roller busbars and the raceway of the ring are both controlled within the range of 85-90% of the total length of the raceway, because within this range, the bearing has better rotational accuracy and high reliability.

Claims

1. A design method for differentiating the roller generatrix of an extra-large double-row tapered roller bearing, characterized in that: Including when designing a bearing, after structural design and static strength check, finite element analysis is carried out to calculate the maximum contact stress borne by each row of rollers; after obtaining two contact stress values, while keeping the contact lengths of the two roller generatrices with the raceway of the ring in the same range of the total length of the raceway, the coefficient value in the bearing generatrix logarithmic function is determined, and the size of the roller protrusion amount is determined by this coefficient value.

2. A method for differential design of the roller generatrix of an extra-large double-row tapered roller bearing according to claim 1, characterized in that: The bearing bus logarithmic function formula is ; In the above formula, L we is the effective length of the roller, x represents the abscissa of the curve, that is, the value of the contact stress, and P x represents the ordinate of the curve; Among them, P x The value is also the convexity deformation amount of the bearing roller. It can be seen from the above formula that when the contact stress values of the two rows of rollers are different, if the convexity deformation amount of the rollers is to be kept the same, the adjustment of the coefficient K value can achieve this.

3. A differential design method for the roller generatrix of an extra-large double-row tapered roller bearing according to claim 1, characterized in that: The contact lengths of the two roller generatrices with the raceway of the ring are both controlled within the range of 85-90% of the total length of the raceway.

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