Method for predicting the interference fit between the sleeve and mandrel during VC roller pressurization

Abstract

This invention discloses a method for predicting the interference fit between the sleeve and mandrel during the hydraulic pressure process of a VC roll, comprising the following steps: S1, collecting equipment parameters of the VC mill under no-hydraulic-pressure conditions; S2, collecting equipment parameters of the VC mill under hydraulic pressure conditions; S3, establishing the geometric relationship between the deformation of the sleeve and mandrel under no-hydraulic-pressure conditions; S4, solving for the interference force p0 under no-hydraulic-pressure conditions; S5, solving for the interference fit G under no-hydraulic-pressure conditions; S6, establishing the relationship between the contact stress p after hydraulic pressure p1 and the interference force p0; S7, solving for the contact stress p after hydraulic pressure; S8, substituting the contact stress p into the interference fit calculation formula to calculate the interference fit G1 after hydraulic pressure. This invention, combined with the structural characteristics of the VC mill, summarizes the influence law of hydraulic pressure on the interference fit between the sleeve and mandrel during the hydraulic pressure process of the VC roll.

Description

Technical Field

[0001] This invention relates to VC rolling mill technology, and more specifically, to a method for predicting the interference fit between the sleeve and the mandrel during the pressurization process of VC rolls. Background Technology

[0002] In recent years, the output of construction machinery and agricultural machinery has maintained rapid growth, and the demand for steel from industries such as home appliances and shipbuilding is also increasing. Compared with traditional rolling mills, VC rolling mills have the advantage of being able to adjust the crown of the rolls by changing the hydraulic pressure according to the different rolled products, thus achieving satisfactory product precision. VC rolls mainly consist of two parts: a mandrel and a sleeve, with an annular oil cavity between the mandrel and the sleeve. During the rolling process, the crown of the sleeve can be adjusted by changing the pressure of the hydraulic oil inside the VC roll's oil cavity. In recent years, the strip and plate industry has developed rapidly. VC rolling mills, due to their flexible shape control and fast response speed, have gradually developed from low-pressure non-ferrous metal rolling to relatively high-pressure ferrous metal rolling. However, with the increase in rolling pressure, the influence of hydraulic pressure on the interference fit and interference force between the VC roll sleeve and the mandrel becomes increasingly complex, thus affecting the crown of the VC roll. In recent years, many scholars at home and abroad have noticed the influence of different oil pressures on the crown of VC rolls and have used the finite element method to solve it approximately. However, this algorithm has too much computation and too long a calculation time, and cannot play a timely prediction role when the rolling mill is working. Summary of the Invention

[0003] To address the shortcomings of existing technologies, the purpose of this invention is to provide a method for predicting the interference fit between the sleeve and mandrel during the pressing process of VC rolls. Based on the structural characteristics of VC rolling mills, the influence law of oil pressure on the interference fit between the sleeve and mandrel during the pressing process of VC rolls is summarized.

[0004] To achieve the above objectives, the present invention adopts the following technical solution:

[0005] A method for predicting the interference fit between the sleeve and the mandrel due to hydraulic pressure during the pressurization process of a VC roller includes the following steps:

[0006] S1. Collect equipment parameters of the VC mill under oil-free conditions;

[0007] S2. Collect equipment parameters of the VC mill under oil pressure conditions;

[0008] S3. Establish the deformation geometric relationship between the sleeve and the mandrel under oil-free conditions;

[0009] S4. Solve for the interference force p0 under the condition of no oil pressure;

[0010] S5. Solve for the interference G under the condition of no oil pressure;

[0011] S6. Establish the relationship between the contact stress p and the interference force p0 after the oil pressure p1 is increased;

[0012] S7. Solve for the contact stress p after oil pressure is applied;

[0013] S8. Substitute the contact stress p into the interference calculation formula to calculate the interference G1 after adding oil pressure.

[0014] Preferably, the equipment parameters of the VC mill in step S1 under oil-free conditions include the inner diameter d1 of the sleeve, the outer diameter d2 of the sleeve, and the diameter d of the mandrel. x Elastic modulus E of the working roll, Poisson's ratio ν of the working roll.

[0015] Preferably, the equipment parameters of the VC mill in step S2 under oil pressure include oil pressure p1, distance l from the support force to the center of the VC roll, distance l1 from the support force to the edge of the oil chamber, and distance l2 from the support force to the edge of the sleeve.

[0016] Preferably, the deformation geometry of the sleeve and mandrel in step S3 includes:

[0017] Establish an unknown quantity, namely a function of the interference force p0:

[0018]

[0019] In the formula, r1 is half the inner diameter of the upper sleeve of the VC roller, r1=d1 / 2; r2 is half the outer diameter of the upper sleeve of the VC roller, r2=d2 / 2.

[0020] Preferably, the interference force p0 in step S4 under the condition of no oil pressure is solved as follows:

[0021]

[0022] Preferably, the interference G in step S5 under the condition of no oil pressure is solved as follows:

[0023]

[0024] Preferably, the relationship between the contact stress p and the interference force p0 after applying oil pressure p1 in step S6 is as follows:

[0025] p(l1-l2)+p1(l-l1)=p0(l1-l2).

[0026] Preferably, the contact stress p after oil pressure in step S7 is calculated as follows:

[0027]

[0028] Preferably, the interference G1 after adding oil pressure in step S8 is calculated as follows:

[0029]

[0030] This invention provides a method for predicting the interference fit between the sleeve and mandrel during the pressurization process of a VC roll. By combining the parameters of the VC rolling mill equipment under both hydraulic and non-hydraulic conditions, the method studies and analyzes the influence of hydraulic pressure on the interference fit between the sleeve and mandrel under these conditions, establishes a model of the influence of hydraulic pressure on the interference fit between the sleeve and mandrel, and calculates the interference force between the sleeve and mandrel. This invention quantifies the interference fit value of the VC roll under different hydraulic pressures, which helps researchers analyze the influence trend of hydraulic pressure on the interference fit of the sleeve and mandrel, and allows for targeted simulation calculations for a specific rolling mill. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of the VC roller structure;

[0032] Figure 2 This is a flowchart illustrating the method for predicting the interference fit between the sleeve and the mandrel during the VC roller pressurization process of the present invention. Detailed Implementation

[0033] To better understand the above-mentioned technical solutions of the present invention, the technical solutions of the present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0034] Combination Figure 1 and Figure 2 As shown, the present invention provides a method for predicting the interference fit between the sleeve and the mandrel during the pressurization process of a VC roller, comprising the following steps:

[0035] S1. Collect the equipment parameters of the VC mill under oil-free conditions, including the inner diameter d1 of sleeve 1, the outer diameter d2 of sleeve 1, and the diameter d of mandrel 2. x Elastic modulus E of the working roll; Poisson's ratio ν of the working roll;

[0036] S2. Collect equipment parameters of the VC mill under oil pressure, including oil pressure p1, distance l from the support force to the center of the VC roll, distance l1 from the support force to the side of the oil chamber 3, and distance l2 from the support force to the side of the sleeve 1.

[0037] S3. Establish the deformation geometry of sleeve 1 and mandrel 2 under oil-free conditions, and establish an unknown quantity, namely a function of interference force p0:

[0038]

[0039] In the formula, r1 is half the inner diameter of the upper sleeve of the VC roller, r1=d1 / 2; r2 is half the outer diameter of the upper sleeve of the VC roller, r2=d2 / 2;

[0040] S4. Solve for the interference force p0 under the condition of no oil pressure, as follows:

[0041]

[0042] S5. Solve for the interference G under the condition of no oil pressure, as follows:

[0043]

[0044] S6. Establish the relationship between the contact stress p and the interference force p0 after the oil pressure p1 is increased, as follows:

[0045] p(l1-l2)+p1(l-l1)=p0(l1-l2)

[0046] S7. Solve for the contact stress p after oil pressure is applied. The solution is as follows:

[0047]

[0048] S8. Substitute the contact stress p into the interference fit calculation formula to calculate the interference fit G1 after oil pressure is applied, as follows:

[0049]

[0050] Example 1

[0051] Combined Figure 1 and Figure 2 As shown in Example 1, the method for predicting the interference fit between the sleeve and the mandrel during the VC roller pressurization process is as follows:

[0052] S1. The inner diameter d1 of the sleeve 1 of a VC rolling mill is 945mm, the outer diameter d2 of the sleeve 1 is 1400mm, and the diameter d of the mandrel 2 is... x The working roll has a diameter of 946.5 mm, an elastic modulus E of 210000 MPa, and a Poisson's ratio ν of 0.3.

[0053] S2. Collect the equipment parameters of the VC mill under oil pressure: oil pressure p1 is 35MPa, distance l from the support force to the center of the support roller is 1360mm, distance l1 from the support force to the side of the oil chamber 3 is 920mm, and distance l2 from the support force to the side of the sleeve 1 is 550mm.

[0054] S3. Establish the deformation geometry of sleeve 1 and mandrel 2 under oil-free conditions, and establish an unknown quantity, namely a function of interference force p0:

[0055]

[0056] In the formula, r1 is half the inner diameter of the upper sleeve of the VC roller, r1=d1 / 2; r2 is half the outer diameter of the upper sleeve of the VC roller, r2=d2 / 2;

[0057] S4. Input parameters: Inner diameter d1 of sleeve 1 for VC roller = 945mm, outer diameter d2 of sleeve 1 for VC roller = 1400mm, diameter d of interference fit of mandrel 2. x =946.5mm, elastic modulus of the work roll E = 210000MPa, Poisson's ratio of the work roll ν = 0.3. Using the above formula, solve for the interference force p0 under the condition of no oil pressure:

[0058]

[0059] The solution yields a value of p0 of 97.4 MPa.

[0060]

[0061] S5. Substitute the obtained inter-roller pressure p0 into the above formula to solve for the value of G, which is 0.7497 mm.

[0062] S6. Establish the relationship between the contact stress p and the interference force p0 after the oil pressure p1 is increased:

[0063] p(l1-l2)+p1(l-l1)=p0(l1-l2)

[0064] S7. Simplify the above formula to obtain the contact stress p after oil pressure is applied.

[0065]

[0066] The solution yielded a contact stress p between the roll and the sleeve after applying oil pressure, which was 55.8 MPa.

[0067] S8. Substitute the contact stress p into the interference calculation formula to calculate the interference G1 after adding oil pressure:

[0068]

[0069] The interference G1 between the roll and the sleeve after adding pressure is calculated to be 0.4298 mm.

[0070] Example 2

[0071] Combined Figure 1 and Figure 2 As shown in Example 2, the method for predicting the interference fit between the sleeve and the mandrel during the VC roller pressurization process is as follows:

[0072] S1. The inner diameter d1 of the sleeve 1 of a VC rolling mill is 945mm, the outer diameter d2 of the sleeve 1 is 1400mm, and the diameter d of the mandrel 2 is...x The working roll has a diameter of 946.5 mm, an elastic modulus E of 210000 MPa, and a Poisson's ratio ν of 0.3.

[0073] S2. Collect the equipment parameters of the VC mill under oil pressure: oil pressure p1 is 40MPa, distance l from the support force to the center of the support roller is 1360mm, distance l1 from the support force to the side of the oil chamber 3 is 920mm, and distance l2 from the support force to the side of the sleeve 1 is 550mm.

[0074] S3. Establish the deformation geometry of sleeve 1 and mandrel 2 under oil-free conditions, and establish an unknown quantity, namely a function of interference force p0:

[0075]

[0076] In the formula, r1 is half the inner diameter of the upper sleeve of the VC roller, r1=d1 / 2; r2 is half the outer diameter of the upper sleeve of the VC roller, r2=d2 / 2;

[0077] S4. Input parameters: Inner diameter d1 of sleeve 1 for VC roller = 945mm, outer diameter d2 of sleeve 1 for VC roller = 1400mm, diameter d of interference fit of mandrel 2. x =946.5mm, elastic modulus of the work roll E = 210000MPa, Poisson's ratio of the work roll ν = 0.3. Using the above formula, solve for the interference force p0 under the condition of no oil pressure:

[0078]

[0079] The solution yields a value of p0 of 97.4 MPa.

[0080]

[0081] S5. Substitute the obtained inter-roller pressure p0 into the above formula to solve for the value of G, which is 0.7497 mm.

[0082] S6. Establish the relationship between the contact stress p and the interference force p0 after the oil pressure p1 is increased:

[0083] p(l1-l2)+p1(l-l1)=p0(l1-l2)

[0084] S7. Simplify the above formula to obtain the contact stress p after oil pressure is applied.

[0085]

[0086] The solution yielded a contact stress p between the roll and the sleeve after applying oil pressure, which was 49.8 MPa.

[0087] S8. Substitute the contact stress p into the interference calculation formula to calculate the interference G1 after adding oil pressure:

[0088]

[0089] The solution yields an interference fit G1 between the roll and the sleeve after applying pressure, which is 0.3837 mm.

[0090] Those skilled in the art should recognize that the above embodiments are merely illustrative of the present invention and are not intended to limit the present invention. Any variations or modifications to the above embodiments that are within the spirit and essence of the present invention will fall within the scope of the claims of the present invention.

Claims

1. A method for predicting the interference fit between the sleeve and the mandrel due to hydraulic pressure during the pressing process of a VC roller, characterized in that, Includes the following steps: S1. Collect equipment parameters of the VC mill under oil-free conditions; S2. Collect equipment parameters of the VC mill under oil pressure conditions; S3. Establish the deformation geometric relationship between the sleeve and the mandrel under oil-free conditions; S4. Solve for the interference force p0 under the condition of no oil pressure; S5. Solve for the interference G under the condition of no oil pressure; S6. Establish the relationship between the contact stress p and the interference force p0 after the oil pressure p1 is increased; S7. Solve for the contact stress p after oil pressure is applied; S8. Substitute the contact stress p into the interference calculation formula to calculate the interference G1 after adding oil pressure. In step S2, the equipment parameters of the VC mill under oil pressure include oil pressure p1, distance l from the support force to the center of the VC roll, distance l1 from the support force to the edge of the oil chamber, and distance l2 from the support force to the edge of the sleeve. The relationship between the contact stress p and the interference force p0 after applying oil pressure p1 in step S6 is as follows: p(l1-l2)+p1(l-l1)=p0(l1-l2).

2. The method for predicting the interference fit between the sleeve and the mandrel during the VC roller pressurization process according to claim 1, characterized in that: In step S1, the equipment parameters of the VC mill under oil-free conditions include the inner diameter d1 of the sleeve, the outer diameter d2 of the sleeve, and the diameter d of the mandrel. x Elastic modulus E of the working roll, Poisson's ratio ν of the working roll.

3. The method for predicting the interference fit between the sleeve and the mandrel during the VC roller pressurization process according to claim 2, characterized in that, The deformation geometry relationships of the sleeve and mandrel in step S3 include: Establish an unknown quantity, namely a function of the interference force p0: In the formula, r1 is half the inner diameter of the upper sleeve of the VC roller, r1=d1 / 2; r2 is half the outer diameter of the upper sleeve of the VC roller, r2=d2 / 2.

4. The method for predicting the interference fit between the sleeve and the mandrel during the VC roller pressurization process according to claim 3, characterized in that, The solution for the interference force p0 under the oil-free state in step S4 is as follows:

5. The method for predicting the interference fit between the sleeve and the mandrel during the VC roller pressurization process according to claim 4, characterized in that, The interference G under the oil-free state in step S5 is calculated as follows:

6. The method for predicting the interference fit between the sleeve and the mandrel during the VC roller pressurization process according to claim 5, characterized in that, The solution for the contact stress p after oil pressure in step S7 is as follows:

7. The method for predicting the interference fit between the sleeve and the mandrel during the VC roller pressurization process according to claim 6, characterized in that, The interference fit G1 after adding oil pressure in step S8 is calculated as follows:

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