Guide rod strength checking method of hydraulic support based on safety standard test

Abstract

The invention relates to a method for checking the strength of a guide rod of a hydraulic support based on a safety standard test. The method comprises the steps that S1, the rated working resistance of the hydraulic support in a preset underground working state, the included angle between the axial direction of a stand column and the vertical face, safety standard test cushion block information and guide rod information are obtained; s2, acquiring a strength safety coefficient K of the guide rod according to the information acquired in the step S1; s3, the strength safety coefficient K is used for checking the strength of the guide rod of the hydraulic support so that the guide rod of the hydraulic support used in the underground coal mine can meet the strength requirement; wherein when the strength safety coefficient K is obtained, the safety standard test stress analysis model provided with the safety standard test cushion block is adopted to process the information, and the strength safety coefficient K is obtained. According to the method, the stress condition of the guide rod in the preset underground working state can be accurately analyzed, the strength safety coefficient K is obtained by adopting the safety standard test stress analysis model provided with the safety standard test cushion block, and therefore it is ensured that the strength of the guide rod meets the underground use requirement of a coal mine.

Description

Technical Field

[0001] The present invention relates to the technical field of hydraulic supports, and in particular to a guide rod strength verification method for a hydraulic support based on a safety standard test. Background Art

[0002] As an important supporting equipment for fully mechanized mining working face, hydraulic support is used to protect the safety of personnel and equipment. Figure 1 、 Figure 2 and Figure 3 The existing roof beam structure includes a roof beam 1, movable side guards 2, a jack 3, a guide rod 4, a spring 5, a locking pin 6, and a roof beam sleeve 7. The movable side guards 2 extend and retract via the guide rods 4 and the sleeves 7 within the roof beam 1, providing both inter-frame sealing and movement guidance. When the hydraulic support is raised, lowered, or moved, the movable side guards 2 simultaneously prevent overturning and adjust the support, significantly impacting the hydraulic support's performance. Because the roof beam structure is in direct contact with the roof of the coal face during fully mechanized mining, the guide rods 4 controlling the unilateral movement of the movable side guards 2 are subject to indirect pressure from the roof, increasing the risk of bending and fracture. "GB 25974 - Hydraulic Supports for Coal Mines" specifies requirements for support testing methods and inspection rules. The loading test on the movable side guards 2, in particular, determines the source of force acting on the guide rods 4. Therefore, strength verification of the movable side guide rods of the roof beam side guards under safety standard testing is particularly important.

[0003] At present, the conventional strength check method of the guide rod of the hydraulic support is to simplify it and establish a mechanical model, in which the gravity of the movable side guard plate 2 and its guide rod 4 is ignored. The positive pressure of the working surface top plate on the hydraulic support is set to F, and the forces on the movable side guard plate 2 and the guide rod 4 are as follows: Figure 3 Specifically, the conventional strength verification method for the guide rod of the movable side guard plate of the bracket top beam includes the following steps:

[0004] Step 1: Calculate the force magnitudes at points A and C of a single guide rod 4 of the movable side guard plate from the support positive pressure F. The force magnitude at point A of the guide rod 4 is:

[0005] F1=F×L2 / L / n

[0006] Where, F1 is the force at point A of the guide rod 4, and its unit is N;

[0007] F is the positive pressure of the hydraulic support, that is, the working resistance of the hydraulic support, and its unit is N;

[0008] L2 is the contact distance between the movable side guard plate 2 on the suspended side of the guide rod 4 and the top plate of the coal mining face, and its unit is mm;

[0009] L is the width of the top beam structure after the movable side guard plate 2 is opened, and its unit is mm;

[0010] n is the number of guide rods 4 on one side of the movable side guard plate 2, and its unit is piece;

[0011] Then, according to the moment balance equation F2×L4=L3×F1, the force at point C of guide rod 4 can be obtained as:

[0012] F2=L3×F1 / L4;

[0013] Where, F2 is the force at point C of the guide rod 4, and its unit is N;

[0014] L3 is the length of the free-standing side of the guide rod 4, in mm;

[0015] L4 is the length of the guide rod 4 included in the top beam sleeve 7, and its unit is mm;

[0016] Step 2: Take the bending moment of point B based on the forces on both sides of the guide rod 4 and take the maximum value M of the two. MAX :

[0017] M1=F1×L3;

[0018] M2=F2×L4;

[0019] Where M1 is the bending moment of the guide rod 4 at point A with respect to point B, and its unit is N*mm;

[0020] M2 is the bending moment of the guide rod 4 at point C with respect to point B, and its unit is N*mm;

[0021] M MAX is the maximum value between M1 and M2;

[0022] Step 3: Calculate the bending stress σ and shear stress τ of the guide rod based on the radius r, bending section coefficient W, and cross-sectional area S of the guide rod 4, and calculate the combined stress σ of the two. 合 :

[0023] σ=M MAX / W;

[0024] τ = F1 / S;

[0025] Where, W is the bending section coefficient of the guide rod 4;

[0026] F1 is the force on point A of guide rod 4, and its unit is N;

[0027] S is the cross-sectional area of ​​the guide rod 4, S = πr 2 , r is the radius of the guide rod 4.

[0028] Step 4: According to the allowable stress σ of the guide rod material 许 / σ 合 The ratio is finally calculated to obtain the guide rod safety factor K. It is generally believed that a guide rod safety factor K greater than 1 meets the requirements.

[0029] At present, the defects and shortcomings of the conventional strength verification method of the guide rod of the hydraulic support are as follows: the guide rod strength verification method is based on the conventional force analysis of the underground support, that is, the positive pressure F of the hydraulic support is calculated according to the working resistance of the support, and does not take into account the support efficiency of the column, that is, the fact that the support column has a vertical angle and the working resistance of the support is reduced. Therefore, the safety factor of the guide rod calculated by the above method is too low; secondly, the above calculation method is based only on the force of the side guard plate of the hydraulic support in the conventional posture, and does not consider the force composition of the side guard plate guide rod under the extreme force (safety standard test condition) of the hydraulic support. In summary, this calculation method deviates from the calculation results of the side guard plate guide rod strength under actual and extreme working conditions underground. Summary of the Invention

[0030] (1) Technical issues to be resolved

[0031] The present invention proposes a method for checking the strength of the guide rods of a hydraulic support based on a safety standard test. The method aims to more accurately evaluate the strength of the guide rods by considering the inclination angle of the columns and the force analysis of the safety standard test, thereby ensuring the stability and safety of the hydraulic support under complex working conditions and making up for the shortcomings of the existing technology.

[0032] (2) Technical solution

[0033] In order to achieve the above objectives, the main technical solutions adopted by the present invention include:

[0034] An embodiment of the present invention provides a guide rod strength verification method for a hydraulic support based on a safety standard test. The hydraulic support includes a base, a column and a top beam structure. One end of the column is connected to the base, and the other end of the column is connected to the top beam structure. The top beam structure includes a top beam, a top beam sleeve, a guide rod and a movable side guard plate. The lower surface of the top beam is provided with a top beam sleeve extending along the width direction of the top beam. The guide rod is movably provided in the top beam sleeve. The movable side guard plate has a top plate and a side plate perpendicular to the top plate. The end of the guide rod is connected to the inner side surface of the side plate. The lower surface of the top plate abuts against the top beam. The upper surface of the top plate is provided with a safety standard test pad.

[0035] The guide rod strength verification method includes the following steps:

[0036] S1. Obtain the rated working resistance F of the hydraulic support in a preset underground working state, the angle α between the axial direction of the column and the vertical plane, the safety test pad information, the movable side guard plate information, and the guide rod information;

[0037] S2. Obtaining a strength safety factor K of the guide rod based on the rated working resistance F of the hydraulic support in a preset underground working state, the angle α between the axial direction of the column and the vertical plane, safety standard test pad information, movable side guard plate information, and guide rod information;

[0038] S3. Use the strength safety factor K to check the strength of the guide rods of the hydraulic support so that the guide rods of the hydraulic support used in coal mines meet the strength requirements;

[0039] Among them, when obtaining the strength safety factor K, the safety test force analysis model after setting the safety test pad is used to process the rated working resistance F of the hydraulic support in the preset underground working state, the angle α between the axial direction of the column and the vertical plane, the safety test pad information, the movable side guard plate information and the guide rod information to obtain the strength safety factor K.

[0040] Optionally, the preset underground working state of the hydraulic support means that the lifting height of the top beam structure of the hydraulic support is consistent with the lifting height of the top beam structure of the hydraulic support when it is in use underground, and the movable side guards on the sides of the top beam structure are all extended.

[0041] Optionally, the connection point between one end of the guide rod and the movable side guard plate is point A, the other end of the guide rod away from the movable side guard plate is point C, the critical point between the section of the guide rod contained in the top beam sleeve and the suspended section of the guide rod is point B, and the critical point between the contact portion of the top plate of the movable side guard plate and the top beam and the suspended portion of the top plate is point D;

[0042] The rated working resistance F of the hydraulic support in the preset underground working state is equal to the sum of the rated working resistances of all the columns of the hydraulic support;

[0043] Safety test pad information includes: the distance a between the safety test pad and the edge of the movable side guard plate, the width b of the safety test pad, and the suspension distance c of the safety test pad relative to point D;

[0044] The movable side guard plate information includes: the total width h of the top plate of the movable side guard plate and the overlap distance e between the top plate of the movable side guard plate 2 and the top beam;

[0045] The guide rod information includes: the number of guide rods n, the length of the free side of the guide rod f, the length of the guide rod included in the top beam sleeve g, the guide rod radius r and the allowable stress σ of the guide rod material 许 The length f of the suspended side of the guide rod is equal to the distance between point A and point B, and the length g of the guide rod included in the top beam sleeve is equal to the distance between point B and point C.

[0046] Optionally, step S2 includes:

[0047] S21. Obtain the safety test pressure F acting on a single safety test pad based on the rated working resistance F of the hydraulic support and the angle α between the axial direction of the column and the vertical plane. 安标 :

[0048] S22, according to the safety test pressure F 安标 and the safety standard test pad information to obtain the hanging force F' acting on the top plate of the movable side guard plate;

[0049] S23. Obtain the force F″ acting on the connection point A between the guide rod and the movable side guard plate based on the suspension force F′ and the safety test pad information;

[0050] S24. Obtain the force F1 at point A and the force F2 at point C of the single guide rod based on the force F″ acting on the connection point A between the guide rod and the movable side guard plate and the guide rod information;

[0051] S25, according to the force F1 at point A and the force F2 at point C of the single guide rod, obtain the bending and torsion M1 of the guide rod at point B due to the force F1 at point A and the bending and torsion M2 of the guide rod at point B due to the force F2 at point C, and take the maximum value of the two as M MAX ;

[0052] S26, according to the maximum bending moment M that the guide rod can bear MAX , the force F1 at point A and the radius r of the guide rod, obtain the bending stress σ and shear stress τ of the guide rod;

[0053] S27, according to the bending stress σ and shear stress τ of the guide rod and the allowable stress σ of the material of the guide rod 许 , obtain the strength safety factor K of the guide rod.

[0054] Optionally, in step S21, the safety test pressure F 安标 From formula (1), we can get:

[0055] F 安标 =1.2×F×COSα / 2 (1)

[0056] Where, F is the rated working resistance of the hydraulic support, and its unit is N;

[0057] α is the angle between the axis of the column and the vertical plane, and its unit is °.

[0058] Optionally, in step S22, the suspension force F′ acting on the top plate of the movable side guard plate is obtained by formula (2):

[0059] F′=(hae) / b×F 安标 (2)

[0060] Where a is the distance between the safety test pad and the edge of the movable side guard plate, and the size of a is 20-50mm;

[0061] b is the width of the safety test pad, and the size of b is 180-220mm;

[0062] h is the total width of the top plate of the movable side guard plate, in mm;

[0063] e is the overlapping distance between the top plate and the top beam when the movable side guard is fully extended, and its unit is mm.

[0064] Optionally, in step S23, the force F″ acting on the connection point A between the guide rod and the movable side guard plate is obtained by formula (3):

[0065]

[0066] Where c is the suspension distance between the safety test pad and the contact point D, and its unit is mm;

[0067] a is the distance between the safety test pad and the edge of the movable side guard plate, and the size of a is 20-50mm.

[0068] Optionally, in step S24, the force F1 at point A of a single guide rod is obtained by formula (4):

[0069] F1=F″ / n (4)

[0070] Where n is the number of guide rods;

[0071] The force F2 at point B of a single guide rod is obtained from formula (5):

[0072] F2=(F1×f) / g (5)

[0073] Where, f is the length of the free-standing side of the guide rod, and its unit is mm;

[0074] g is the length of the guide rod included in the top beam sleeve, and its unit is mm.

[0075] Optionally, in step S24, the bending and torsion M1 of the guide rod point B caused by the force F1 at point A is obtained by formula (6):

[0076] M1=F1×f (6)

[0077] Where, f is the length of the free-standing side of the guide rod, and its unit is mm;

[0078] The bending and torsion M2 of the guide rod at point B due to the force F2 at point C is obtained from formula (7):

[0079] M1=F2×g (7)

[0080] Where g is the length of the guide rod included in the top beam sleeve, and its unit is mm.

[0081] Optionally, in step S26, the bending stress σ of the guide rod is obtained by formula (8):

[0082] σ=M max / π(2r) 3 ×32 (8)

[0083] Where r is the radius of the guide rod, and its unit is mm;

[0084] The shear stress τ on the guide rod is obtained from formula (9):

[0085] τ=F1 / (πr 2 ) (9)

[0086] Where r is the radius of the guide rod, and its unit is mm;

[0087] In step S27, the strength safety factor K of the guide rod is obtained by formula (10):

[0088]

[0089] Where, σ 许 is the allowable stress of the guide rod material.

[0090] (3) Beneficial effects

[0091] The beneficial effects of the present invention are as follows: the guide rod strength verification method of the hydraulic support based on the safety standard test of the present invention comprises a base, a column and a top beam structure, one end of the column is connected to the base, and the other end of the column is connected to the top beam structure, the top beam structure comprises a top beam, a top beam sleeve, a guide rod and a movable side guard plate, a top beam sleeve extending in the width direction of the top beam is provided on the lower surface of the top beam, a guide rod is movably provided in the top beam sleeve, the movable side guard plate has a top plate and a side plate perpendicular to the top plate, the end of the guide rod is connected to the inner side surface of the side plate, the lower surface of the top plate abuts against the top beam, and the upper surface of the top plate is provided with a safety standard test pad; the guide rod strength verification method comprises the following steps: S1, obtaining the rated working resistance F of the hydraulic support in a preset underground working state, the angle α between the axial direction of the column and the vertical plane, Safety test pad information, movable side guard plate information, and guide rod information; S2. According to the rated working resistance F of the hydraulic support in the preset underground working state, the angle α between the axial direction of the column and the vertical plane, the safety test pad information, the movable side guard plate information, and the guide rod information, the strength safety factor K of the guide rod is obtained; S3. The strength safety factor K is used for the strength verification of the guide rod of the hydraulic support, so that the guide rod of the hydraulic support used in the coal mine meets the strength requirements; wherein, when obtaining the strength safety factor K, the safety test force analysis model after setting the safety test pad is used to process the rated working resistance F of the hydraulic support in the preset underground working state, the angle α between the axial direction of the column and the vertical plane, the safety test pad information and the guide rod information to obtain the strength safety factor K. Compared with the conventional guide rod strength verification method of the hydraulic support, the guide rod strength verification method of the present invention takes into account the characteristics of the angle between the columns of the hydraulic support when working underground and in the safety test posture. The calculated single-sided positive pressure result of the support is more in line with reality. Adding the safety test pad and analyzing the force on the guide rod in this area is the basis for the subsequent calculation of the guide rod safety factor, which solves the problem of the force source of the guide rod of the side guard plate of the support top beam and avoids the problem that the calculation process of this part in the existing technology is too macro and rough. Based on the above two advantages, the obtained guide rod strength safety factor is more in line with reality and the strength is guaranteed, which is conducive to avoiding problems such as excessive guide rod strength, waste of materials or low strength, component damage, etc., and is also conducive to timely design adjustments of the hydraulic support, and truly realizes the design of inherently safe and lightweight support products.

[0092] The guide rod strength verification method of the hydraulic support based on the safety standard test of the present invention comprises the following steps: S21, according to the rated working resistance F of the hydraulic support and the angle α between the axial direction of the column and the vertical plane, obtaining the safety standard test pressure F acting on a single safety standard test pad. 安标 :S22, according to the safety test pressure F 安标and safety test pad information, obtain the hanging force F' acting on the top plate of the movable side guard plate; S23, according to the hanging force F' and the safety test pad information, obtain the force F" acting on the connection point A of the guide rod and the movable side guard plate; S24, according to the force F" acting on the connection point A of the guide rod and the movable side guard plate and the guide rod information, obtain the force F1 at point A and the force F2 at point C of the single guide rod; S25, according to the force F1 at point A and the force F2 at point C of the single guide rod, obtain the bending and torsion M1 of the force F1 at point A on the guide rod point B and the bending and torsion M2 of the force F2 at point C on the guide rod point B, and take the maximum value of the two as M MAX ; S26, according to the maximum bending moment M that the guide rod can withstand MAX , the force F1 at point A and the radius r of the guide rod are used to obtain the bending stress σ and shear stress τ of the guide rod; S27, according to the bending stress σ and shear stress τ of the guide rod and the allowable stress σ of the material of the guide rod 许 , obtain the strength safety factor K of the guide rod, in S21, the safety test pressure F 安标 It is derived from the following formula: F 安标 =1.2×F×COSα / 2, that is, the safety test pressure F 安标 Based on 1.2 times the rated working resistance of the support, the advantage of adding this part of the calculation is that it is closer to the actual working of the hydraulic support on the basis of ensuring the strength of the component under extreme stress conditions of the guide rod, making the subsequent calculation results of the guide rod strength safety factor more accurate. BRIEF DESCRIPTION OF THE DRAWINGS

[0093] Figure 1 It is a three-dimensional schematic diagram of the top beam structure of an existing hydraulic support;

[0094] Figure 2 for Figure 1 A three-dimensional diagram of the side guard plates, jacks, guide rods and springs inside the top beam structure from an upward perspective;

[0095] Figure 3 The diagram is a schematic diagram of the internal structure of the existing top beam structure and a schematic diagram of the force analysis of the movable side guard plate guide rod in the extended state;

[0096] Figure 4 This is a schematic diagram of the working posture of the hydraulic support;

[0097] Figure 5 A schematic diagram of the internal structure of the top beam structure of the present invention and a schematic diagram of the force analysis of the movable side guard plate guide rod in the extended state;

[0098] Figure 6 The present invention is a flow chart of a method for checking the guide rod strength of a hydraulic support based on a safety standard test.

[0099] [Description of Reference Numerals]

[0100] 1: Top beam; 2: Movable side guard; 3: Jack; 4: Guide rod; 5: Spring; 6: Lock pin; 7: Top beam sleeve; 8: Column; 9: Safety test pad; 10: Base. DETAILED DESCRIPTION

[0101] In order to better explain the present invention and facilitate understanding, the present invention is described in detail below with reference to the accompanying drawings and through specific embodiments. Figure 5 The orientation is referenced.

[0102] See also Figure 1 、 Figure 2 、 Figure 4 and Figure 5 The guide rod strength verification method of the hydraulic support based on the safety standard test of this embodiment is applied to the hydraulic support. The hydraulic support includes a base 10, a column 8 and a top beam structure.

[0103] One end of the column 8 is connected to the base 10, and the other end of the column 8 is connected to the top beam structure. The top beam structure includes a top beam 1, a top beam sleeve 7, a guide rod 4 and a movable side guard plate 2. The lower surface of the top beam 1 is provided with a top beam sleeve 7 extending along the width direction of the top beam 1. The guide rod 4 is movably arranged in the top beam sleeve 7. The movable side guard plate 2 has a top plate and a side plate perpendicular to the top plate. The end of the guide rod 4 is connected to the inner side of the side plate, the lower surface of the top plate is in contact with the top beam 1, and the upper surface of the top plate is provided with a safety test pad 9.

[0104] Combine Figure 6 As shown, the guide rod strength verification method of the hydraulic support based on the safety standard test of this embodiment includes the following steps:

[0105] S1. Obtain the rated working resistance F of the hydraulic support in a preset downhole working state, the angle α between the axis of the column 8 and the vertical plane, information about the safety test pad 9, information about the movable side guard plate 2, and information about the guide rod 4;

[0106] S2. Obtaining a strength safety factor K of the guide rod 4 based on the rated working resistance F of the hydraulic support in a preset downhole working state, the angle α between the axis of the column 8 and the vertical plane, information about the safety standard test pad 9, information about the movable side guard plate 2, and information about the guide rod 4;

[0107] S3. Use the strength safety factor K to check the strength of the guide rod of the hydraulic support so that the guide rod 4 of the hydraulic support used in the coal mine meets the strength requirements;

[0108] Among them, when obtaining the strength safety factor K, the safety test force analysis model after setting the safety test pad 9 is used to process the rated working resistance F of the hydraulic support in the preset underground working state, the angle α between the axial direction and the vertical plane of the column 8, the safety test pad 9 information, the movable side guard plate 2 information and the guide rod 4 information to obtain the strength safety factor K.

[0109] It should be noted that the computer is the main body for executing the guide rod strength verification method of the hydraulic support based on the safety standard test in this embodiment.

[0110] In the embodiments of the present invention, the preset underground operating state of the hydraulic support refers to the elevation height of the top beam structure of the hydraulic support being consistent with the elevation height of the top beam structure during the hydraulic support's actual underground operation. Furthermore, the safety standard test stipulates that during the safety standard test, the movable side guard plates 2 on the sides of the top beam structure must be fully extended. It should be noted that the full extension of the movable side guard plates 2 means that the top plate of the movable side guard plates 2 is fully extended, i.e., the top plate of the movable side guard plates 2 is extended to the maximum extent possible.

[0111] See also Figure 5 The contact area between the movable side guard plate 2 and the top beam 1 is taken as the research object, the connection point between one end of the guide rod 4 and the movable side guard plate 2 is point A, the other end of the guide rod 4 away from the movable side guard plate 2 is point C, the critical point between the section of the guide rod 4 contained in the top beam sleeve 7 and the suspended section of the guide rod 4 is point B, and the critical point between the contact part of the top plate of the movable side guard plate 2 and the top beam 1 and the suspended part of the top plate is point D.

[0112] Specifically, the rated working resistance F of the hydraulic support in a preset downhole working state is equal to the sum of the rated working resistances of all the columns 8 of the hydraulic support.

[0113] Specifically, the information of the safety test pad 9 includes: the distance a between the safety test pad 9 and the edge of the movable side guard plate 2, the width b of the safety test pad 9, and the suspension distance c of the safety test pad 9 relative to point D.

[0114] Specifically, the information of the movable side guard plate 2 includes: the total width h of the top plate of the movable side guard plate 2 and the overlapping distance e between the top plate of the movable side guard plate 2 and the top beam 1 .

[0115] Specifically, the information of the guide rod 4 includes: the number n of the guide rods 4, the length f of the free side of the guide rod 4, the length g of the section of the guide rod 4 included in the top beam sleeve 7, the radius r of the guide rod 4, and the allowable stress σ of the material of the guide rod 4 许The length f of the free-standing portion of guide rod 4 is equal to the distance between points A and B, and the length g of the portion of guide rod 4 contained within top beam sleeve 7 is equal to the distance between points B and C. It should be noted that point A is the connection point between one end of guide rod 4 and movable side guard plate 2, point B is the critical point between the portion of guide rod 4 contained within top beam sleeve 7 and the free-standing portion of guide rod 4, and point C is the other end of guide rod 4 away from movable side guard plate 2.

[0116] In some preferred embodiments of the present invention, step S2 includes:

[0117] S21. Obtain the safety test pressure F acting on a single safety test pad 9 based on the rated working resistance F of the hydraulic support and the angle α between the axial direction of the column 8 and the vertical plane. 安标 :

[0118] S22, according to the safety test pressure F 安标 and the safety test pad 9 information to obtain the suspension force F′ acting on the top plate of the movable side guard plate 2;

[0119] S23. Obtain the force F″ acting on the connection point A between the guide rod 4 and the movable side guard plate 2 based on the suspension force F′ and the information of the safety test pad 9;

[0120] S24, obtaining the force F1 at point A and the force F2 at point C of the single guide rod 4 based on the force F″ acting on the connection point A between the guide rod 4 and the movable side guard plate 2 and the information of the guide rod 4;

[0121] S25, according to the force F1 at point A and the force F2 at point C of the single guide rod 4, obtain the bending and torsion M1 of the guide rod point B caused by the force F1 at point A and the bending and torsion M2 of the guide rod point B caused by the force F2 at point C, and take the maximum value of the two as M MAX ;

[0122] S26, according to the maximum bending moment M borne by the guide rod 4 MAX , the force F1 at point A and the radius r of the guide rod 4, obtain the bending stress σ and shear stress τ of the guide rod 4;

[0123] S27, according to the bending stress σ and shear stress τ of the guide rod 4 and the material allowable stress σ of the guide rod 4 许 , obtain the strength safety factor K of the guide rod 4.

[0124] In some preferred embodiments of the present invention, in step S21, the safety test pressure F 安标 From formula (1), we can get:

[0125] F 安标 =1.2×F×COSα / 2 (1)

[0126] Where, F is the rated working resistance of the hydraulic support, and its unit is N;

[0127] α is the angle between the axial direction of the column 8 and the vertical plane, and its unit is °.

[0128] In the guide rod strength verification method of the hydraulic support based on the safety standard test of this embodiment, a safety standard test pad 9 is provided on the upper surface of each of the two movable side guard plates 2. The rated working resistance F of the hydraulic support is multiplied by COSα to obtain the maximum positive pressure that the hydraulic support can withstand in the vertical direction, and then multiplied by 1.2 times, and finally divided by 2 to obtain the safety standard test pressure F of the single safety standard test pad 9 acting on the movable side guard plate 2. 安标 It takes into account the angle between the upright column 8 and the hydraulic support during underground operation and in the safety test posture, and calculates the positive pressure of the hydraulic support based on 1.2 times the rated working resistance. The advantage of adding this part of the calculation is that it is closer to the actual operation of the support on the basis of ensuring the strength of the guide rod 4 under extreme stress conditions, making the subsequent calculation results of the guide rod strength safety factor more accurate.

[0129] See Figure 5 In the partial enlarged diagram, the contact area between the movable side guard plate 2 and the top beam 1 is taken as the research object. Point D is the critical point between the top plate of the movable side guard plate 2 and the contact point. Assuming that the safety test pressure of the top beam 1 acts entirely on the safety test pad 9, and considering that the safety test pad 9 partially overlaps with the top beam 1 and the top plate of the movable side guard plate 2 (the overlap distance is d), the force acting on the top plate of the movable side guard plate 2 in the air is F′=c / b×F 安标 , then in step S22, the suspension force F′ acting on the top plate of the movable side guard plate 2 can be obtained by formula (2):

[0130] F′=(hae) / b×F 安标 (2)

[0131] Wherein, a is the distance between the safety test pad 9 and the edge of the movable side guard plate 2, and the size of a is 20-50mm;

[0132] b is the width of the safety test pad 9, and the size of b is 180-220mm;

[0133] h is the total width of the top plate of the movable side guard plate 2, in mm;

[0134] e is the overlap distance between the top plate and the top beam 1 when the movable side guard plate 2 is fully extended, and its unit is mm.

[0135] Preferably, in step S23, the force F″ acting on the connection point A between the guide rod 4 and the movable side guard plate 2 is obtained by formula (3):

[0136]

[0137] Where c is the suspension distance between the safety test pad 9 and the contact point D, and its unit is mm;

[0138] a is the distance between the safety test pad 9 and the edge of the movable side guard plate 2, and the size of a is 20-50mm.

[0139] Assuming that the suspension force F′ acts at c / 2, the torque of the suspension force F′ on the contact area point D is F′×c / 2. Then, the torque balance equation of the force F″ at point A connecting the guide rod 4 and the movable side guard plate 2 and the suspension force F′ on the contact area point D is: F″×(a+c)=F′×c / 2, from which the above formula (3) can be derived.

[0140] Preferably, the length direction of the safety test pad 9 of this embodiment is parallel to the front-rear direction of the hydraulic support, and the length of the safety test pad 9 is 1800-2200 mm.

[0141] The guide rod strength verification method of the hydraulic support based on the safety standard test of this embodiment adds a safety standard test pad 9 to the upper surface of the movable side guard plate 2, and performs a force analysis on the guide rod 4 in this area, which is the basis for the subsequent calculation of the safety factor of the guide rod strength, solves the problem of the force source of the guide rod 4, and avoids the problem that this part of the calculation process in the prior art is too macroscopic and rough.

[0142] Preferably, in step S24, the force F1 at point A of the single guide rod 4 is obtained by formula (4):

[0143] F1=F″ / n (4)

[0144] Wherein, n is the number of guide rods 4.

[0145] The force F2 at point B of a single guide rod 4 is obtained from formula (5):

[0146] F2=(F1×f) / g (5)

[0147] Where, f is the length of the free-standing side of the guide rod 4, and its unit is mm;

[0148] g is the length of the section where the guide rod 4 is included in the top beam sleeve 7, and its unit is mm.

[0149] It should be noted that the above formula (5) is derived from the moment balance equation of F1 and F2 at point B in the contact area.

[0150] Preferably, in step S24, the bending and torsion M1 of the guide rod point B caused by the force F1 at point A is obtained by formula (6):

[0151] M1=F1×f (6)

[0152] Wherein, f is the length of the suspended side of the guide rod 4, and its unit is mm.

[0153] The bending and torsion M2 of the guide rod at point B due to the force F2 at point C is obtained from formula (7):

[0154] M1=F2×g (7)

[0155] Wherein, g is the length of the section where the guide rod 4 is included in the top beam sleeve 7, and its unit is mm.

[0156] Preferably, in step S26, the bending stress σ of the guide rod 4 is obtained by formula (8):

[0157] σ=M max / π(2r) 3 ×32 (8)

[0158] Where r is the radius of the guide rod 4, and its unit is mm;

[0159] The shear stress τ on the guide rod 4 is obtained from formula (9):

[0160] τ=F1 / (πr 2 ) (9)

[0161] Wherein, r is the radius of the guide rod 4, and its unit is mm.

[0162] M MAX is the maximum value between M1 and M2, that is, if M1 is greater than M2, M MAX Equal to M1, if M2 is greater than M1, M MAX Equal to M2.

[0163] It should be noted that π(2r) 3 / 32 is equal to the bending section coefficient W of the guide rod 4, πr 2 Equal to the cross-sectional area S of the guide rod 4.

[0164] Preferably, in step S27, the strength safety factor K of the guide rod 4 is obtained by formula (10):

[0165]

[0166] Where, σ 许 is the allowable material stress of the guide rod 4.

[0167] It should be noted that according to the fourth strength theory in material mechanics, the resultant stress σ on the guide rod 4 is 合 It is derived from the following formula:

[0168]

[0169] The strength safety factor K of the guide rod 4 is equal to the allowable stress σ of the material of the guide rod 4 许Divide by the total stress σ on guide rod 4 合 .

[0170] In some preferred embodiments of the present invention, step S3 includes determining whether the strength safety factor K of guide rods 4 is greater than 1. If so, the design and selection of guide rods 4 are reasonable, and their strength can meet the requirements for use in coal mines. If not, the design and selection of guide rods 4 are unreasonable, and the design is redesigned to increase the number and / or diameter of guide rods 4.

[0171] Preferably, step S5 further includes: determining whether the strength safety factor K of the guide rod 4 is greater than 5: if so, the design and selection of the guide rod 4 are too redundant, and the guide rod 4 is redesigned to reduce the number and / or diameter of the guide rods 4.

[0172] The guide rod strength verification method of the hydraulic support based on the safety standard test in this embodiment has a guide rod strength safety factor that is more in line with reality and has guaranteed strength, which is beneficial to avoiding problems such as excessive strength of the guide rod 4, waste of materials or low strength, and damage to components. It is also beneficial for the hydraulic support to make timely design adjustments and truly realize the design of an intrinsically safe and lightweight support product.

[0173] In the description of the present invention, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of the technical features indicated. Therefore, a feature specified as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, "plurality" means two or more, unless otherwise specifically defined.

[0174] In the present invention, unless otherwise expressly specified or limited, the terms "mounted," "connected," "connect," "fixed," etc. should be understood broadly. For example, they may refer to fixed connection, detachable connection, or integration; mechanical connection or electrical connection; direct connection or indirect connection through an intermediate medium; and internal communication between two components or interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0175] In the present invention, unless otherwise expressly specified or limited, when a first feature is "above" or "below" a second feature, it may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Furthermore, when a first feature is "above," "above," or "above" a second feature, it may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is at a higher level than the second feature. When a first feature is "below," "below," or "below" a second feature, it may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is at a lower level than the second feature.

[0176] In the description of this specification, the terms "one embodiment", "some embodiments", "embodiments", "examples", "specific examples" or "some examples" refer to the specific features, structures, materials or characteristics described in conjunction with the embodiment or example and included in at least one embodiment or example of the present invention. In this specification, the schematic expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine different embodiments or examples described in this specification and features of different embodiments or examples, unless they are mutually inconsistent.

[0177] Although the embodiments of the present invention have been shown and described above, it will be understood that the above embodiments are illustrative and are not to be construed as limitations on the present invention. A person skilled in the art may alter, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. A method for checking the guide rod strength of a hydraulic support based on a safety standard test, characterized in that: The hydraulic support includes a base, a column and a top beam structure. One end of the column is connected to the base, and the other end of the column is connected to the top beam structure. The top beam structure includes a top beam, a top beam sleeve, a guide rod and a movable side guard plate. The lower surface of the top beam is provided with a top beam sleeve extending along the width direction of the top beam. The guide rod is movably provided in the top beam sleeve. The movable side guard plate has a top plate and a side plate perpendicular to the top plate. The end of the guide rod is connected to the inner side of the side plate. The lower surface of the top plate abuts against the top beam. The upper surface of the top plate is provided with a safety standard test pad. The guide rod strength verification method includes the following steps: S1. Obtain the rated working resistance F of the hydraulic support in a preset underground working state, the angle α between the axial direction of the column and the vertical plane, the safety test pad information, the movable side guard plate information, and the guide rod information; S2. Obtaining a strength safety factor K of the guide rod based on the rated working resistance F of the hydraulic support in a preset underground working state, the angle α between the axial direction of the column and the vertical plane, safety standard test pad information, movable side guard plate information, and guide rod information; S3. Use the strength safety factor K to check the strength of the guide rods of the hydraulic support so that the guide rods of the hydraulic support used in coal mines meet the strength requirements; Among them, when obtaining the strength safety factor K, the safety test force analysis model after setting the safety test pad is used to process the rated working resistance F of the hydraulic support in the preset underground working state, the angle α between the axial direction of the column and the vertical plane, the safety test pad information, the movable side guard plate information and the guide rod information to obtain the strength safety factor K.

2. The guide rod strength verification method for a hydraulic support based on a safety standard test according to claim 1 is characterized in that: The preset underground working state of the hydraulic support means that the lifting height of the top beam structure of the hydraulic support is consistent with the lifting height of the top beam structure when the hydraulic support is in use underground, and the movable side guards on the sides of the top beam structure are all extended.

3. The guide rod strength verification method for a hydraulic support based on a safety standard test according to claim 1 is characterized in that: The connection point between one end of the guide rod and the movable side guard plate is point A, the other end of the guide rod away from the movable side guard plate is point C, the critical point between the section of the guide rod contained in the top beam sleeve and the suspended section of the guide rod is point B, and the critical point between the contact part between the top plate of the movable side guard plate and the top beam and the suspended part of the top plate is point D. The rated working resistance F of the hydraulic support in the preset underground working state is equal to the sum of the rated working resistances of all the columns of the hydraulic support; Safety test pad information includes: the distance a between the safety test pad and the edge of the movable side guard plate, the width b of the safety test pad, and the suspension distance c of the safety test pad relative to point D; The movable side guard plate information includes: the total width h of the top plate of the movable side guard plate and the overlap distance e between the top plate of the movable side guard plate and the top beam; The guide rod information includes: the number of guide rods n, the length of the free side of the guide rod f, the length of the guide rod included in the top beam sleeve g, the guide rod radius r and the allowable stress σ of the guide rod material 许 The length f of the suspended side of the guide rod is equal to the distance between point A and point B, and the length g of the guide rod included in the top beam sleeve is equal to the distance between point B and point C.

4. The guide rod strength verification method for a hydraulic support based on a safety standard test according to claim 3 is characterized in that: Step S2 includes: S21. Obtain the safety test pressure F acting on a single safety test pad based on the rated working resistance F of the hydraulic support and the angle α between the axial direction of the column and the vertical plane. 安标 : S22, according to the safety test pressure F 安标 and the safety standard test pad information to obtain the hanging force F' acting on the top plate of the movable side guard plate; S23. Obtain the force F″ acting on the connection point A between the guide rod and the movable side guard plate based on the suspension force F′ and the safety test pad information; S24. Obtain the force F1 at point A and the force F2 at point C of the single guide rod based on the force F″ acting on the connection point A between the guide rod and the movable side guard plate and the guide rod information; S25, according to the force F1 at point A and the force F2 at point C of the single guide rod, obtain the bending and torsion M1 of the guide rod at point B due to the force F1 at point A and the bending and torsion M2 of the guide rod at point B due to the force F2 at point C, and take the maximum value of the two as M MAX ; S26, according to the maximum bending moment M that the guide rod can bear MAX , the force F1 at point A and the radius r of the guide rod, obtain the bending stress σ and shear stress τ of the guide rod; S27, according to the bending stress σ and shear stress τ of the guide rod and the allowable stress σ of the material of the guide rod 许 , obtain the strength safety factor K of the guide rod.

5. The guide rod strength verification method for a hydraulic support based on a safety standard test according to claim 4 is characterized in that: In step S21, the safety test pressure F 安标 From formula (1), we can get: F 安标 =1.2×F×COSα / 2 (1) Where, F is the rated working resistance of the hydraulic support, and its unit is N; α is the angle between the axis of the column and the vertical plane, and its unit is °.

6. The guide rod strength verification method for a hydraulic support based on a safety standard test according to claim 4, characterized in that: In step S22, the suspension force F′ acting on the top plate of the movable side guard plate is obtained by formula (2): F′=(h-a-e) / b×F 安标 (2) Where a is the distance between the safety test pad and the edge of the movable side guard plate, and the size of a is 20-50mm; b is the width of the safety test pad, and the size of b is 180-220mm; h is the total width of the top plate of the movable side guard plate, in mm; e is the overlapping distance between the top plate and the top beam when the movable side guard is fully extended, and its unit is mm.

7. The method for checking the guide rod strength of a hydraulic support based on a safety standard test according to claim 4, characterized in that: In step S23, the force F″ acting on the connection point A between the guide rod and the movable side guard plate is obtained by formula (3): Where c is the suspension distance between the safety test pad and the contact point D, and its unit is mm; a is the distance between the safety test pad and the edge of the movable side guard plate, and the size of a is 20-50mm.

8. The method for checking the guide rod strength of a hydraulic support based on a safety standard test according to claim 4, characterized in that: In step S24, the force F1 at point A of a single guide rod is obtained by formula (4): F1=F″ / n (4) Where n is the number of guide rods; The force F2 at point B of a single guide rod is obtained from formula (5): F2=(F1×f) / g (5) Where, f is the length of the free-standing side of the guide rod, and its unit is mm; g is the length of the guide rod included in the top beam sleeve, and its unit is mm.

9. The method for checking the guide rod strength of a hydraulic support based on a safety standard test according to claim 4, characterized in that: In step S24, the bending and torsion M1 of the guide rod B caused by the force F1 at point A is obtained by formula (6): M1=F1×f (6) Where, f is the length of the free-standing side of the guide rod, and its unit is mm; The bending and torsion M2 of the guide rod at point B due to the force F2 at point C is obtained from formula (7): M1=F2×g (7) Where g is the length of the guide rod included in the top beam sleeve, and its unit is mm.

10. The method for checking the guide rod strength of a hydraulic support based on a safety standard test according to claim 4, characterized in that: In step S26, the bending stress σ on the guide rod is obtained by formula (8): σ=M max / π(2r) 3 ×32 (8) Where r is the radius of the guide rod, and its unit is mm; The shear stress τ on the guide rod is obtained from formula (9): τ=F1 / (πr 2 ) (9) Where r is the radius of the guide rod, and its unit is mm; In step S27, the strength safety factor K of the guide rod is obtained by formula (10): Where, σ 许 is the allowable stress of the guide rod material.

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