Screw conveyer model selection method

Abstract

The invention discloses a spiral conveyor model selection method. The method comprises the steps that demand information is obtained; calculating the relation between the diameter of the screw conveyer and the semi-cone angle of the screw according to a maximum error formula; the relation is substituted into a conveying amount formula of the spiral conveyor, and the rotating speed range of the spiral conveyor is worked out; according to the relation between the rotating speed range of the screw conveyor and the diameter of the screw conveyor, the optimal rotating speed and diameter are found out in the database; according to the method, on the basis of conventional conveying capacity calculation, two important parameters including errors and manufacturing cost are creatively introduced, and the manufacturing cost is determined through the diameter and rotation of the spiral conveyor. Through the improvement, the optimal design scheme which is economical and meets the conveying error requirement can be obtained through one-time calculation; not only is the design efficiency of the spiral conveyor improved, but also the economical efficiency and the practicability of the spiral conveyor are optimized.

Description

Technical Field

[0001] The invention relates to the field of material transportation, in particular to a method for selecting a screw conveyor. Background Art

[0002] In the existing technical field, the performance evaluation and design optimization of screw conveyors, as a mechanical device widely used in material transportation, mainly focus on calculating the hourly conveying volume. These calculations are essential to ensure that the screw conveyor can meet basic material handling needs. However, there is a significant limitation in the current calculation methods, that is, they usually ignore the inherent connection between the design of the screw conveyor and the cost and conveying error. This also leads to the fact that screw conveyors are generally not used for metering. If metering is required, additional metering devices are required.

[0003] Specifically, although engineers and designers can determine the conveying capacity of screw conveyors based on traditional calculation methods, these calculations do not take into account cost factors and errors in the conveying process. Cost is one of the key factors that determine the economic efficiency of screw conveyors, while conveying errors are directly related to conveying efficiency and accuracy. The lack of comprehensive consideration of these factors often leads to the design of screw conveyors that meet the conveying requirements in theory, but may face problems of high cost or insufficient conveying accuracy in actual applications. Summary of the invention

[0004] Therefore, in order to solve the above-mentioned shortcomings, the present invention provides a method for selecting a screw conveyor. Based on the conventional conveying capacity calculation, the method creatively introduces two important parameters, namely, error and cost, wherein the cost is determined by the diameter and transmission of the screw conveyor. Through this improvement, the present invention can achieve a one-time calculation to obtain the optimal design solution that is both economical and meets the conveying error requirements; it not only improves the design efficiency of the screw conveyor, but also optimizes its economy and practicality.

[0005] Specifically, a method for selecting a screw conveyor includes the following steps:

[0006] Obtaining demand information, the demand information at least includes a conveying efficiency and a conveying volume error range when conveying materials; wherein the material properties at least include the viscosity and density of the material, wherein the viscosity is represented by an adhesion constant; wherein the conveying efficiency is a maximum conveying volume per minute within the error range;

[0007] The relationship between the diameter of the screw conveyor and the semi-cone angle of the screw is calculated based on the maximum error formula;

[0008] Substitute the above relationship into the screw conveyor's conveying capacity formula to find the speed range of the screw conveyor;

[0009] According to the relationship between the speed range of the screw conveyor and the diameter of the screw conveyor, find the optimal speed and diameter in the database.

[0010] The present invention has the following advantages:

[0011] Based on the conventional conveying capacity calculation, the present invention creatively introduces two important parameters: error and cost (determined by the diameter and rotation of the screw conveyor). Through this improvement, the present invention can obtain the optimal design scheme that is both economical and meets the conveying error requirements in a one-time calculation.

[0012] This method improves the accuracy and economy of screw conveyor design. By comprehensively considering multiple key parameters such as speed, semi-cone angle of the screw, density and viscosity of the material, as well as the error and conveying efficiency requirements proposed by the user, this algorithm can calculate the diameter and semi-cone angle of the screw conveyor blade, thereby ensuring that the conveyor can achieve the expected conveying efficiency and error control level in actual operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a schematic diagram of the process of the present invention. DETAILED DESCRIPTION

[0014] Embodiments of the present application are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present application, and should not be construed as limiting the present application.

[0015] In this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprises", or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article, or apparatus that includes a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article, or apparatus.

[0016] As described in the background technology, specifically, although engineers and designers can determine the conveying capacity of screw conveyors based on traditional calculation methods, these calculations do not take into account cost factors and errors in the conveying process. Cost is one of the key factors that determine the economic efficiency of screw conveyors, and conveying errors are directly related to conveying efficiency and accuracy. The lack of comprehensive consideration of these factors often leads to the design of screw conveyors that meet the conveying requirements in theory, but may face problems of excessive cost or insufficient conveying accuracy in actual applications.

[0017] Based on the above reasons, this embodiment provides a method for selecting a screw conveyor, comprising the following steps:

[0018] Step S100, obtaining demand information, the demand information at least including material properties, conveying efficiency and conveying volume error range when conveying materials; wherein the material properties at least include the viscosity and density of the material, wherein the viscosity is represented by the adhesion constant; wherein the conveying efficiency is the maximum conveying volume per minute within the error range;

[0019] Exemplarily, the detection method for expressing the adhesion constant is to place a naturally stacked 10mm×10mm×10mm material on a plane, and the angle between the plane and the horizontal plane gradually increases from 0°. When more than 50% of the material slides off the plane, the ratio of the angle between the plane and the horizontal plane to 90° is the material adhesion constant G.

[0020] Step S200, calculating the relationship between the diameter of the screw conveyor and the semi-cone angle of the screw according to the maximum error formula;

[0021] Exemplarily, step S200 includes the following steps:

[0022] Step S201, set the maximum error formula as follows:

[0023]

[0024] Among them: E is the maximum error, K is the error correction coefficient, G is the material adhesion constant, d is the diameter of the screw conveyor, ρ is the true density of the material, and α is the semi-cone angle of the screw. Among them, the material adhesion constant G is in the range of 0 to 1; the semi-cone angle α of the screw can be smaller when conveying materials with good fluidity; when conveying materials with poor fluidity, the angle can be appropriately increased, generally between 5-70°, the larger the G, the larger the semi-cone angle α, and the value of the semi-cone angle α is generally greater than the angle between the plane and the horizontal plane when more than 20% to 60% of the material slides off the plane when measuring the material adhesion constant G.

[0025] Step S202: The relationship between the diameter of the screw conveyor and the semi-cone angle of the screw is expressed by the following first modified formula:

[0026]

[0027] Step S300: Substitute the above relationship into the conveying capacity formula of the screw conveyor to calculate the speed range of the screw conveyor.

[0028] Exemplarily, step S300 includes the following steps:

[0029] Step S301, the following conveying amount formula is set based on the relationship between the conveying amount of the screw conveyor and its diameter and screw distance:

[0030]

[0031] Among them, Q is the maximum conveying volume per minute, d is the diameter of the screw conveyor, n is the speed, γ is the bulk density of the material, and α is the semi-cone angle of the screw;

[0032] Step S302: After the above-mentioned delivery amount formula is deformed, the following second deformation formula is obtained:

[0033]

[0034] Step S303, combining the first deformation formula with the second deformation formula to form the following third deformation formula;

[0035]

[0036] Step S304: After deformation, the following fourth deformation formula is obtained, and the speed range of the screw conveyor is determined by the formula:

[0037]

[0038] In the fourth variation formula, Q, K, G, ρ, E and γ are all given requirements or physical parameters of the material itself, and are all known numbers, so the maximum speed requirement can be calculated. According to the maximum rotational speed requirement, the most economical motor can be queried in the database. The database is pre-formed, and the database at least includes information such as motor price, motor speed, and the price of common steel.

[0039] Step S400: Find the optimal speed and diameter in the database according to the relationship between the speed range of the screw conveyor and the diameter of the screw conveyor.

[0040] Exemplarily, the specific method of step S400 is:

[0041] The formula Substituting this into the most economical motor speed above, we get the following inequality:

[0042]

[0043] in All are given requirements or physical parameters of the material itself, all are known numbers. When α is selected, That is, it is a fixed value, d2≥fixed value, and the minimum d can be obtained. d determines the amount of processing material used, and n determines the cost of the motor. Therefore, by comparing the database, find the minimum value of n, which is the optimal solution, that is, the optimal screw conveyor selection.

[0044] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for selecting a screw conveyor, characterized in that: The steps include: Obtaining demand information, the demand information at least includes a conveying efficiency and a conveying volume error range when conveying materials; wherein the material properties at least include the viscosity and density of the material, wherein the viscosity is represented by an adhesion constant; wherein the conveying efficiency is a maximum conveying volume per minute within the error range; The relationship between the diameter of the screw conveyor and the semi-cone angle of the screw is calculated based on the maximum error formula; Substitute the above relationship into the screw conveyor's conveying capacity formula to find out the speed range of the screw conveyor; based on the relationship between the speed range of the screw conveyor and the diameter of the screw conveyor, find the optimal speed and diameter in the database.

2. A method for selecting a screw conveyor according to claim 1, characterized in that: The specific method to calculate the relationship between the diameter of the screw conveyor and the semi-cone angle of the screw according to the maximum error formula is: Assume the maximum error formula is: Where: E is the maximum error, K is the error correction coefficient, G is the material adhesion constant, d is the diameter of the screw conveyor, ρ is the true density of the material, and α is the semi-cone angle of the screw; The relationship between the diameter and the semi-cone angle of the spiral is expressed by the following formula:

3. A method for selecting a screw conveyor according to claim 2, characterized in that: The delivery volume formula is as follows: Where: Q is the maximum conveying volume per minute, d is the diameter of the screw conveyor, n is the rotation speed, and γ is the bulk density of the material; Substituting the inequality expressing the relationship between the diameter and the semi-cone angle of the screw into the above conveying capacity formula, the speed range of the screw conveyor is as follows:

4. A method for selecting a screw conveyor according to claim 2, characterized in that: The relationship between the speed range of the screw conveyor and the diameter of the screw conveyor is determined by the following formula: When α is selected, is a fixed value, that is, d2 ≥ fixed value, and the minimum d can be obtained. d determines the amount of processing material used, and n determines the cost of the motor.

5. A method for selecting a screw conveyor according to claim 1, characterized in that: The detection method for expressing the adhesion constant is to place naturally stacked 10mm×10mm×10mm materials on a plane, and the angle between the plane and the horizontal plane gradually increases from 0°. When more than 50% of the materials slide off the plane, the ratio of the angle between the plane and the horizontal plane to 90° is the material adhesion constant G.

6. A method for selecting a screw conveyor according to claim 2, characterized in that: When conveying materials with good fluidity, the smaller the value of the semi-cone angle α is; When the material conveying fluidity is poor, the value of the semi-cone angle α is larger.

7. A method for selecting a screw conveyor according to claim 2, characterized in that: The value range of the semi-cone angle α is 5-70°; when the semi-cone angle α is greater than the set value when the material adhesion constant G is measured, and the material slides off the plane, the semi-cone angle α is the angle between the plane and the horizontal plane at this time.

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