Calculation method for wire rope inclination angle change of large-span conveying system support saddle under all working conditions

Abstract

The present application relates to the field of material conveying, and specifically discloses a large-span conveying system support saddle steel wire rope full working condition inclination angle change calculation method; comprising the following steps: step 1, determining the height of the starting point and the ending point of the conveying system, and determining the side with lower height as left and the side with higher height as right; step 2, determining the support, determining the test working condition, and the uniformly distributed load, chord inclination angle, chord length and height under the test working condition; step 3, calculating the steel wire rope tension on the left side of the support, calculating the steel wire rope tension on the right side of the support; step 4, calculating the left side inclination angle of the support, and when the left side chord line of the support is below the horizontal line, the left side inclination angle takes a positive number; when the left side chord line of the support is above the horizontal line, the left side inclination angle takes a negative number; calculating the right side inclination angle of the support; step 5, calculating the support fold angle; the large-span conveying system support saddle steel wire rope full working condition inclination angle change calculation method in the present application can improve the safety of the belt conveyor during operation.

Description

Technical Field

[0001] This invention relates to the field of material conveying, specifically to a method for calculating the inclination angle variation of the steel wire rope on the support saddle of a large-span conveying system under all working conditions. Background Technology

[0002] Belt conveyors (also known as cable-stayed belt conveyors or cable bridge belt conveyors) are long-distance, large-span bulk material conveying equipment that uses pylons, main suspension cables, and suspenders to suspend the truss and conveyor frame. They are suitable for conveying bulk materials such as coal and ore across valleys, rivers, and roads in scenarios such as mines, power plants, and ports. They have advantages such as large span, strong terrain adaptability, small footprint, and good environmental performance.

[0003] Existing belt conveyors include structures such as supports, wire ropes, hangers, and belts. The wire ropes and belts extend along the conveying path, the supports provide support for the wire ropes, and the hangers are located on the wire ropes and support the belts. Since the supports are installed on the ground, the position where the supports support the wire ropes will vary in height depending on the terrain, resulting in differences in the inclination angle of the wire ropes on both sides of the supports.

[0004] Currently, there is no systematic method for calculating the inclination angle change of wire ropes in belt conveyors, which raises questions about the safety of the wire ropes: there is a risk of insufficient pressure causing the wire rope to dislodge from the saddle and the rope itself to wear out. Summary of the Invention

[0005] The present invention aims to provide a method for calculating the inclination angle variation of the steel wire rope of the support saddle in a large-span conveying system under all working conditions, so as to improve the safety of belt conveyors during operation.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: a method for calculating the inclination angle variation of the steel wire rope of the support saddle in a large-span conveying system under all working conditions, comprising the following steps: Step 1: Determine the height of the starting and ending points of the conveying system, and designate the side with the lower height as the left and the side with the higher height as the right. Step 2: Determine support i, designate the support to the left of support i as support (i-1), and the support to the right of support i as support (i+1). Determine the test condition and the uniformly distributed load q under this test condition. c Inclination angle α （i） chord length l （i） and elevation difference h （i） ; Step 3, calculate the tension T' of the wire rope on the left side of the support i according to the following formula (1). z(i) : (1); Calculate the tension T' of the wire rope on the right side of the support i according to the following formula (2). y(i) : (2); Step 4, calculate the left tilt angle βz(i) of the support i according to the following formula (3): (3); When the left chord of bracket i is below the horizontal line, the left tilt angle is positive; when the left chord of bracket i is above the horizontal line, the left tilt angle is negative. The right-side tilt angle βy(i) of the support i is calculated according to the following formula (4): (4); When the right chord of bracket i is below the horizontal line, the right inclination angle is positive; when the right chord of bracket i is above the horizontal line, the right inclination angle is negative. Step 5, calculate the bracket i-angle δ according to the following formula (5). （i） : (5).

[0007] In this scheme, the chord inclination angle refers to the inclination angle between the contact point between the wire rope and the support between two adjacent supports.

[0008] Chord length refers to the slant length between the contact point between the wire rope and the support between two adjacent supports.

[0009] Elevation difference h （i） This refers to the height difference between the contact points between the wire rope and the support between two adjacent supports.

[0010] The beneficial effects of this plan are: 1. Traditional belt conveyors have relatively short conveying distances, and even without systematic calculation of the inclination angle, they are not prone to danger. The method in this solution is applied to ultra-long distances with spans of 1000m and above, ensuring safety under such large conveying distances and spans. This solution calculates the bending angle using the above formula. After verification, when the bending angle is negative and the value is large, it indicates that the terrain of the line is relatively steep, and there is a risk that the wire rope may not be able to effectively adhere to the support saddle. When the bending angle is positive and the value is large, it indicates that the support is under great stress at that point, and there is a possibility of excessive wear on the wire rope and uneven operation.

[0011] Wire ropes are prone to slipping off the saddle, causing the hangers and belts that are mounted on the wire ropes to fall. This can lead to the material on the belts falling as well, especially when the material is heavy. The falling material can also cause trees to break, rocks to fall, and animals or even people passing below to be injured. When the angle is positive but the value is too large, the sign of the angle can be used to assess the safety of the system.

[0012] 2. Traditional cable cars and ropeways calculate the inclination angle as the angle between the cable chord and the horizontal line. The calculation focuses on structural geometric parameters and wire rope tension, with the requirement that the inclination angle not exceed the specified limits. Furthermore, cable cars and ropeways operate at low speeds and with minimal fluctuations in operating conditions; even when calculations are performed, they only consider static geometric inclination angles. However, the conveying system in this scheme requires cross-city and even cross-province transport over long distances, thus demanding higher speeds. The actual operating conditions of the conveying system are completely different from those of cable cars and ropeways. This scheme substitutes the wire rope tension on the right side of support i into the formula for calculating the wire rope tension on the left side of support i+1. This allows the inclination angle calculation for each support in the entire conveying system to be performed sequentially from left to right, resulting in better systemicity and accommodating the significant differences in operating conditions on both sides of the support.

[0013] Furthermore, it also includes step 6, where when the angle is negative, the angle is increased by at least one of the following methods: reducing the radius of curvature of the saddle on the support i to accommodate the large angle, or increasing the height h of the support i until the angle is positive.

[0014] Furthermore, when the angle is positive and greater than the preset value, at least one of the following methods can be used to reduce the angle: reduce the height of the support, form a chain frame, or use a saddle with a larger radius of curvature.

[0015] The beneficial effects of this solution are as follows: by adjusting the saddle and increasing the height of the support, this solution can directly change the force between the wire rope and the saddle, thereby more directly changing the left and right tilt angles. The overall adjustment range is small and the cost is low.

[0016] Furthermore, the number of test conditions in step 2 is greater than 1, and the calculations in steps 2 to 5 are repeated to obtain the bending angle under each test condition. In step 6, the maximum and minimum bending angles among all bending angles are first determined, and the adjustment of the saddle angle is completed based on the maximum and minimum bending angles, ensuring that the bending angles of the test conditions corresponding to the maximum and minimum bending angles after adjustment are all positive numbers.

[0017] Furthermore, the test conditions in step 2 include empty rope, no load, and full load. The empty rope means that only the steel wire rope is installed on the support; the no load means that the system is assembled but no material is being transported; and the full load means that the material with the maximum load is being transported.

[0018] The beneficial effects of this solution are as follows: This solution calculates the bending angle under multiple working conditions, which can simulate the safety under different working conditions. Thus, when the bending angle error caused by external forces such as wind load and measurement error leads to the error in adjusting the saddle angle, it effectively improves the accuracy of saddle adjustment. Moreover, when both the maximum and minimum bending angles meet the requirements, it proves that the bending angles corresponding to the above test working conditions meet the requirements, that is, the system has a high safety under the above test working conditions.

[0019] Furthermore, the test conditions in step 2 also include combining the conditions on both sides of the support to make the conditions on both sides different.

[0020] Furthermore, the test conditions in step 2 also include the maximum tension condition. The maximum tension condition is calculated by multiplying the tension of the left wire rope and the tension of the right wire rope under no-load conditions by a coefficient n, where n is a constant greater than 1, and then performing the calculations of formula (2) and formula (3).

[0021] Furthermore, the test conditions in step 2 also include the system suddenly shutting down during operation.

[0022] The beneficial effects of this solution are: in practical applications, the working conditions on both sides of the wire rope are complex under the action of external forces. This solution can further expand the range of test conditions, thereby improving safety. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the conveying system according to an embodiment of the present invention; Figure 2 for Figure 1 Installation diagram of the middle bracket i. Detailed Implementation

[0024] The following detailed description illustrates the specific implementation method: Example The implementation examples are basically as follows Figure 1 and Figure 2 As shown, a method for calculating the inclination angle variation of the steel wire rope on the support saddle of a long-span conveying system under all working conditions is disclosed, including the following steps: Step 1: Determine the height of the starting and ending points of the conveying system, and designate the side with the lower height as the left and the side with the higher height as the right. Number the supports sequentially from the starting point to the ending point as 1, 2, 3...n; Step 2: Determine the support i. The support to the left of support i is designated as support (i-1), and the support to the right of support i is designated as support (i+1). i is an integer greater than 0, and when i=0, there will be no support (i-1) to the left of support i. The number of test conditions is greater than 1. The test conditions include empty rope, no load, full load, maximum tension, and sudden shutdown of the system during operation. The above test conditions are numbered as Condition 1, Condition 2... Condition 5 respectively. Empty rope means that only steel wire rope is installed on the support; no load means that the system is assembled but no material is being transported; full load means that the material with the maximum load is being transported. Determine operating condition 1, and the load q under this test condition. （i） Inclination angle α （i） chord length l （i） and elevation difference h （i） In actual implementation, the elevation difference h in this embodiment （i） The height difference between the contact point between the steel wire rope on support i and the left support (i-1) and the saddle on that support; Step 3, calculate the tension T' of the wire rope on the left side of the support i according to the following formula (1). z(i) : (1); Among them T' y(i-1) In this embodiment, q represents the tension in the right-side steel wire rope of the left-side support. c The value is taken as the equivalent uniformly distributed load of the line; Calculate the tension T' of the wire rope on the right side of support i according to the following formula (2). y(i) : (2); Where △T （i） The specific value, △T, is determined based on the materials of the saddle and the wire rope. （i） =2×μ×T min ×sin(δmax / 2), where μ is the coefficient of friction between the wire rope and the support, which is taken as 0.1~0.12 in this scheme, T min The minimum tension in the wire rope on the right side of support i is given by δmax / 2, which is half of the maximum bending angle. When calculating the tension in the wire rope on the right side of support 1, T' is used. y(i) The value is either the initial tension of the wire rope or the tension of the counterweight.

[0025] In actual implementation, a graph showing the relationship between the frictional force between the wire rope and the saddle and the tension of the wire rope is established. Then, the corresponding tension is selected as ΔT(i) according to the design requirements: when the design requirements are high, the tension value corresponding to the larger frictional force is selected, and when the design requirements are low, the tension value corresponding to the smaller frictional force is selected.

[0026] In actual implementation, the calculated wire rope tension on the right side of support i is substituted into the formula for calculating the wire rope tension T' on the left side of support i+1. z(i+1) .

[0027] Step 4, calculate the left tilt angle β of the support i according to the following formula (3). z(i) : (3); When the left chord of bracket i is below the horizontal line, the left tilt angle is positive; when the left chord of bracket i is above the horizontal line, the left tilt angle is negative. The right-side tilt angle β of the support i is calculated according to the following formula (4). y(i) : (4); When the right chord of bracket i is below the horizontal line, the right inclination angle is positive; when the right chord of bracket i is above the horizontal line, the right inclination angle is negative. Step 5, calculate the bracket i-angle δ according to the following formula (5). （i） : (5); Step 6, repeat steps 2-4 above, and determine the bending angles corresponding to working conditions 2 to 5 in turn. When the test working condition is the maximum tension condition, calculate the tension of the left wire rope and the tension of the right wire rope under no-load conditions. First, multiply the tension of the left wire rope and the tension of the right wire rope by a coefficient n, where n is a constant greater than 1, and then perform the calculations of formula (2) and formula (3). In addition, the working conditions on the left and right sides of the support are combined to make the working condition numbers on the two sides of the support different, and the above steps 2-4 are repeated to determine the bending angle corresponding to the working condition combination in turn. First, determine the maximum and minimum bend angles among all bend angles. When any bend angle is negative, increase the bend angle using at least one of the following methods: reduce the radius of curvature of the saddle on bracket i to accommodate the large bend angle, or increase the height h of bracket i until the bend angle becomes positive. When any bend angle is positive and greater than a preset value, decrease the bend angle using at least one of the following methods: reduce the bracket height, form a chain frame, or use a saddle with a larger radius of curvature. In actual implementation, the preset value is determined based on the material of the saddle and the wire rope, ensuring that the wire rope is not rapidly worn.

[0028] The above descriptions are merely embodiments of the present invention, and common knowledge such as specific technical solutions and / or characteristics are not described in detail here. It should be noted that those skilled in the art can make various modifications and improvements without departing from the technical solutions of the present invention, and these should also be considered within the scope of protection of the present invention. These modifications and improvements will not affect the effectiveness of the implementation of the present invention or the practicality of the patent. The scope of protection claimed in this application should be determined by the content of its claims, and the specific embodiments described in the specification can be used to interpret the content of the claims.

Claims

1. A method for calculating the inclination angle variation of the steel wire rope on the support saddle of a large-span conveying system under all working conditions, characterized in that: Includes the following steps: Step 1: Determine the height of the starting and ending points of the conveying system, and designate the side with the lower height as the left and the side with the higher height as the right. Step 2: Determine support i, designate the support to the left of support i as support (i-1), and the support to the right of support i as support (i+1). Determine the test condition and the uniformly distributed load q under this test condition. c Inclination angle α （i） chord length l （i） and height difference h （i） ; Step 3, calculate the tension T' of the wire rope on the left side of the support i according to the following formula (1). z(i) : （1）； Calculate the tension T' of the wire rope on the right side of support i according to the following formula (2). y(i) : （2）； Step 4, calculate the left tilt angle βz(i) of the support i according to the following formula (3): （3）； When the left chord of bracket i is below the horizontal line, the left tilt angle is positive; when the left chord of bracket i is above the horizontal line, the left tilt angle is negative. The right-side tilt angle βy(i) of the support i is calculated according to the following formula (4): （4）； When the right chord of bracket i is below the horizontal line, the right inclination angle is positive; when the right chord of bracket i is above the horizontal line, the right inclination angle is negative. Step 5, calculate the bracket i-angle δ according to the following formula (5). （i） : （5）。 2. The method for calculating the inclination angle variation of the steel wire rope on the support saddle of a large-span conveying system under all working conditions as described in claim 1, is characterized in that: It also includes step 6, where when the angle is negative, the angle is increased by at least one of the following methods: reducing the radius of curvature of the saddle on the support i to accommodate the large angle or increasing the height h of the support i until the angle is positive.

3. The method for calculating the inclination angle variation of the steel wire rope of the support saddle in a large-span conveying system under all working conditions as described in claim 2, is characterized in that: When the angle is positive and greater than the preset value, at least one of the following methods can be used to reduce the angle: reduce the height of the support, form a chain frame, or use a saddle with a larger radius of curvature.

4. The method for calculating the inclination angle variation of the steel wire rope of the support saddle in a large-span conveying system under all working conditions, as described in claim 2 or 3, is characterized in that: Step 2 involves testing more than one condition and repeating the calculations from Step 2 to Step 5 to obtain the bend angle for each test condition. Step 6 first determines the maximum and minimum bend angles among all bend angles. The adjustment of the saddle angle is then completed based on the maximum and minimum bend angles, ensuring that the bend angles for the test conditions corresponding to the maximum and minimum bend angles are positive numbers after adjustment.

5. The method for calculating the inclination angle variation of the steel wire rope of the support saddle in a large-span conveying system under all working conditions, as described in claim 4, is characterized in that: The test conditions in step 2 include empty rope, no load, and full load. Empty rope means that only steel wire rope is installed on the support; no load means that the system is assembled but no material is being transported; full load means that the maximum load of material is being transported.

6. The method for calculating the inclination angle variation of the steel wire rope on the support saddle of a large-span conveying system under all working conditions, as described in claim 5, is characterized in that: Step 2 of the test also includes combining the working conditions on both sides of the support to make the working conditions on both sides different.

7. The method for calculating the inclination angle variation of the steel wire rope of the support saddle in a large-span conveying system under all working conditions, as described in claim 5, is characterized in that: The test conditions in step 2 also include the maximum tension condition. The maximum tension condition is calculated by multiplying the tension of the left wire rope and the tension of the right wire rope under no-load conditions by a coefficient n, where n is a constant greater than 1, and then performing the calculations of formula (2) and formula (3).

8. The method for calculating the inclination angle variation of the steel wire rope of the support saddle in a large-span conveying system under all working conditions, as described in claim 5, is characterized in that: The test conditions in step 2 also include the system suddenly shutting down during operation.

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