Methods for adjusting the length and turning of irregular coal mining faces

Abstract

This invention discloses a method for adjusting the length and turning of irregularly shaped coal mining faces, including the following steps: determining the advancing distance at both ends of the face during the turning process; designing overhead cylinders and ground cylinders between the hydraulic supports of the face for coordinated turning; strengthening the support at the widened section of the machine roadway; and monitoring and adapting ventilation and transportation during the face turning process. This invention provides a complete workflow for turning irregularly shaped coal mining faces and a calculation method for widening the machine roadway at the turning point. Simultaneously, by introducing overhead cylinders and ground cylinders between the top beam and base of two adjacent hydraulic supports, and coordinating the turning of hydraulic supports at different positions on the face, a calculation basis for the face turning can be provided, ensuring the safety of face mining and transportation during the face turning process.

Description

Technical Field

[0001] This invention relates to the field of digital mining technology services, and in particular to a method for adjusting the length and turning of irregularly shaped coal mining faces. Background Technology

[0002] Coal mining often encounters complex geological structures such as faults and folds, or the mine design may employ a combined layout of mining areas and panels, resulting in oblique intersections when working faces are arranged in the same area. Both situations lead to a large number of working faces requiring turning. Traditional longarm mining methods face the following difficulties when turning working faces: 1. The hydraulic supports of the working face must remain perpendicular to the working face at all times, and the working face must maintain a linear turning direction. 2. The bridge-type transfer conveyor is relatively long, making it difficult to pass through inflection points during turning. 3. The length of the working face changes during turning, requiring the addition or reduction of hydraulic supports and chutes, involving the connection issues between various processes on the working face. 4. Ensuring ventilation and transportation in roadways and at the working face is difficult during turning. Summary of the Invention

[0003] To address the aforementioned technical problems, this invention provides a simple, safe, and reliable method for adjusting and turning the length of irregularly shaped coal mining faces.

[0004] The technical solution of this invention to solve the above-mentioned technical problems is: a method for adjusting and turning the length of irregularly shaped coal mining faces, comprising the following steps:

[0005] Step 1: Determine the advancing distance at both ends of the working face during the turning process;

[0006] Step 2: Design overhead cylinders and ground cylinders between the hydraulic supports on the working face for coordinated steering;

[0007] Step 3: Strengthen the support of the widened section of the machine roadway;

[0008] Step 4: Monitoring and adaptation of ventilation and transportation during the working face turning period.

[0009] The specific process of step 1 in the above-mentioned method for adjusting and turning the length of irregularly shaped coal mining faces is as follows:

[0010] Step 11: Determine the inflection point of the working face. When the working face turns, the center point of the machine roadway on the side closest to the center of the turning circle is the inflection point. The machine roadway is divided into the roadway before the turn and the roadway after the turn.

[0011] Step 12: Determine the length of the centerline of the bridge transfer machine when it is retracted to its shortest length, based on the model of the bridge transfer machine used on the working face;

[0012] Step 13: Draw a reference circle with the determined inflection point as the center;

[0013] Step 14: Draw the starting line and ending line of the working face turning, and the intersection of the starting line and the ending line of the working face turning is the center of the turning circle;

[0014] Step 15: Determine the widening range and degree of the machine roadway based on the starting line and stopping line of the working face turning;

[0015] Step 16: With the center of the turning circle as the vertex, and the starting line and the stopping line of the working face turning as the two sides, form an angle. Draw a bisector of the angle. The bisector intersects the inner line of the roadway before turning and the inner line of the roadway after turning. The distance between two adjacent bisectors is the advancing distance during the working face turning process.

[0016] Step 17: Divide the working face into equal sections based on the actual coal cutting advance as the basic unit. Determine the pushing distance ratio at both ends of the working face during the turning process based on the similarity ratio of each equal triangle.

[0017] In the above-mentioned method for adjusting the length and turning of irregular coal mining faces, in step 13, let the intersection of the reference circle and the center line of the roadway before turning be s1, and the intersection of the reference circle and the center line of the roadway after turning be s2. Let the straight distance between s1 and s2 be d1, then d1=d2, and d2 is the length of the centerline when the bridge transfer machine is contracted to its shortest length.

[0018] In the above-mentioned method for adjusting the length and turning of irregular coal mining faces, in step 14, a straight line parallel to the working face before turning is drawn through the intersection point s1 of the reference circle and the center line of the roadway before turning, which is the starting line of the working face turning; a straight line parallel to the working face after turning is drawn through the intersection point s2 of the reference circle and the center line of the roadway after turning, which is the stopping line of the working face turning; both the starting line and the stopping line of the working face turning are tangent to the reference circle.

[0019] In the above-mentioned method for adjusting and turning the length of irregular coal mining faces, in step 15, the area of ​​the intersection of the starting line of the turning of the working face, the stopping line of the turning of the working face, and the outer line of the machine roadway where the turning point is located is taken as the widening range of the machine roadway and the machine roadway is widened; the boundary line of the machine roadway after widening is parallel to the line connecting s1 and s2, and the vertical distance between the turning point and the boundary line of the machine roadway after widening is half the width of the machine roadway where the turning point is located.

[0020] In the above-mentioned method for adjusting and turning the length of irregular coal mining faces, in step 2, a hydraulic cylinder is installed between the top beam and the base body of two adjacent hydraulic supports. The hydraulic cylinder between the two top beams is called the top cylinder, and the hydraulic cylinder between the two base bodies is called the bottom cylinder. The center lines of the top cylinder and the bottom cylinder on the same support are on the same vertical plane to ensure that the hydraulic support is pushed synchronously and coordinated during the turning process.

[0021] In the above-mentioned method for adjusting and turning the length of irregular coal mining faces, in step 2, during the turning process of the working face, the overhead cylinder and the ground cylinder extend and retract simultaneously, coordinating to control the turning of the hydraulic support, so that the hydraulic support is always perpendicular to the working face.

[0022] In the above-mentioned method for adjusting and turning the length of irregular coal mining faces, in step 3, local reinforcement support is required at the widening point of the machine roadway. The support method is determined based on the roof span, lithology, ground stress, and mining influence conditions at the widening point of the machine roadway.

[0023] In the above-mentioned method for adjusting the length and turning of irregular coal mining faces, in step 4, during the turning process of the working face, both the roadway before and after the turning are involved in the turning, and the turning point also involves the widening of the machine roadway. The working face equipment continuously adjusts its orientation during the turning process. Therefore, the ventilation resistance and transportation capacity of the working face and the mining roadways on both sides are calculated and adjusted in real time. At the same time, the gas concentration monitoring at the turning point is strengthened to ensure the safe mining of the working face.

[0024] The above-mentioned method for adjusting the length and turning of irregular coal mining faces involves moving the face's advance supports to both sides of the machine roadway in advance when the face advances to the turning range to ensure that the hydraulic support frame and the bridge transfer machine can pass through; at the same time, the length of the bridge transfer machine is reduced to the shortest possible length to ensure that the face can pass through the turning point when turning.

[0025] The beneficial effects of this invention are as follows: This invention provides a complete workflow for the turning of irregularly shaped coal mining faces and a calculation method for the widening of the machine roadway at the turning point. Simultaneously, it creatively introduces overhead cylinders and ground cylinders between the top beam and base of two adjacent hydraulic supports, coordinating with the hydraulic supports at different positions on the working face for coordinated turning. This provides a calculation basis for the turning of the working face and ensures the safety of mining and transportation during the turning process. Attached Figure Description

[0026] Figure 1 This is the overall flowchart of the present invention.

[0027] Figure 2 This is a schematic diagram of the working surface.

[0028] Figure 3 This is a schematic diagram of the widened section of the machine lane.

[0029] In the diagram, 1 is the machine roadway, 2 is the bridge transfer machine, 3 is the reference circle, 4 is the inflection point, 5 is the center of the turning circle, 6 is the starting line of the working face turning, 7 is the stopping line of the working face turning, 8 is the widening point of the machine roadway, and 9 is the mining roadway. Detailed Implementation

[0030] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0031] like Figures 1-3 As shown, the method for adjusting the length and turning of an irregularly shaped coal mining face includes the following steps:

[0032] Step 1: Determine the advancing distance at both ends of the working face during the turning process;

[0033] The specific process of step 1 is as follows:

[0034] Step 11: Determine the inflection point 4 of the working face. When the working face turns, the center point of the machine roadway 1 on the side closest to the center 5 of the turning circle is the inflection point 4. The machine roadway 1 is divided into the roadway before the turn and the roadway after the turn.

[0035] Step 12: Determine the length of the central axis of the bridge transfer machine 2 when it is retracted to its shortest length, based on the model of the bridge transfer machine used on the working face;

[0036] Step 13: Draw a reference circle 3 with the determined inflection point 4 as the center; let the intersection of the reference circle 3 and the center line of the roadway before the turn be s1, and the intersection of the reference circle 3 and the center line of the roadway after the turn be s2. Let the straight distance between s1 and s2 be d1, then d1=d2, and d2 is the length of the centerline of the bridge transfer machine 2 when it is contracted to the shortest length.

[0037] Step 14: Draw the starting line 6 and the stopping line 7 of the working face turning, and the intersection of the starting line 6 and the stopping line 7 is the center 5 of the turning circle.

[0038] Draw a straight line parallel to the working face before turning through the intersection point s1 of the reference circle 3 and the center line of the roadway before turning, which is the starting line 6 of the working face turning; draw a straight line parallel to the working face after turning through the intersection point s2 of the reference circle 3 and the center line of the roadway after turning, which is the stopping line 7 of the working face turning; the starting line 6 and the stopping line 7 of the working face turning are both tangent to the reference circle 3.

[0039] Step 15: Determine the widening range and degree of the machine roadway based on the working face turning start line 6 and the working face turning stop line 7;

[0040] The area of ​​the intersection of the working face turning start line 6, the working face turning stop line 7 and the outer line of the machine roadway where the inflection point 4 is located is taken as the machine roadway widening area and the machine roadway is widened; the boundary line of the machine roadway after widening is parallel to the line connecting s1 and s2, and the vertical distance between the inflection point and the boundary line of the machine roadway after widening is half the width of the machine roadway where the inflection point is located.

[0041] Step 16: With the center 5 of the turning circle as the vertex, the starting line 6 and the stopping line 7 of the working face turning as the two sides, form an angle. Draw a bisector of the angle. The bisector intersects the inner line of the roadway before turning and the inner line of the roadway after turning. The distance between two adjacent bisectors is the advancing distance during the turning process of the working face.

[0042] Step 17: Divide the working face into equal sections based on the actual coal cutting advance as the basic unit. Determine the pushing distance ratio at both ends of the working face during the turning process based on the similarity ratio of each equal triangle.

[0043] Step 2: Design overhead cylinders and ground cylinders between the hydraulic supports on the working face for coordinated steering.

[0044] The hydraulic support consists of a top beam, hydraulic cylinders, and a base. During normal working face advancement, it moves in a straight line along the working face. However, turning the working face is involved, and turning large hydraulic supports is relatively difficult. Therefore, this invention incorporates overhead cylinders and ground cylinders between the hydraulic supports to assist in their rotation. Specifically, a hydraulic cylinder is installed between the top beam and the base of two adjacent hydraulic supports. The hydraulic cylinder between the two top beams is called the overhead cylinder, and the hydraulic cylinder between the two bases is called the ground cylinder. The centerlines of the overhead cylinder and the ground cylinder on the same support are on the same vertical plane, ensuring synchronous and coordinated movement of the hydraulic support during turning.

[0045] During the turning process of the working face, the top cylinder and the bottom cylinder extend and retract simultaneously, working together to control the turning of the hydraulic support, so that the hydraulic support is always perpendicular to the working face.

[0046] Step 3: Strengthen the support of the widened section of the machine roadway.

[0047] Local reinforcement support is required at the widened section 8 of the machine roadway. The support method is determined based on the roof span, lithology, ground stress, and mining impact conditions at the widened section 8 of the machine roadway.

[0048] Step 4: Monitoring and adaptation of ventilation and transportation during the working face turning period.

[0049] During the turning process of the working face, both the roadways before and after the turn involve turning, and the turning point 4 also involves widening the machine roadway. The working face equipment continuously adjusts its orientation during the turning process. Therefore, the ventilation resistance and transportation capacity of the working face and the two side mining roadways 9 are calculated and adjusted in real time. The calculation method for ventilation resistance and transportation capacity is existing technology and will not be described in detail in this invention. The adjustment method is as follows: if the ventilation resistance is too high (exceeding the set threshold), the equal division angle during the working face turning process is increased to enlarge the working face cross-section; the transportation capacity is adjusted by adjusting the specifications and models of the three machines matched on the working face. At the same time, the gas concentration monitoring at the turning point is strengthened to ensure safe mining of the working face.

[0050] Work process coordination during the steering process:

[0051] 1. When the working face advances to the turning range, the working face advance support is moved to the two sides of the machine roadway 1 in advance to ensure that the hydraulic support, chute and bridge transfer machine 2 can pass through; the chute is below the hydraulic support, and the coal cut by the coal mining machine is transported by the chute to the transfer machine and transported out by belt.

[0052] 2. Transport the hydraulic supports and chutes to the side of the working face that needs to be lengthened. Use the production shift to increase or decrease the hydraulic supports on the working face, and use the maintenance shift to increase or decrease the chutes on the working face.

[0053] 3. When the working face advances to the turning range, shorten the length of the bridge transfer machine 2 to the shortest possible length to ensure that the working face can pass through the turning point 4 when turning.

[0054] 4. During the change of working face length, the support should be added first, followed by the chute. During the removal of the support, the chute should be removed first, followed by the support.

Claims

1. A method for adjusting the length and turning of irregularly shaped coal mining faces, characterized in that, Includes the following steps: Step 1: Determine the advancing distance at both ends of the working face during the turning process; Step 2: Design overhead cylinders and ground cylinders between the hydraulic supports on the working face for coordinated steering; Step 3: Strengthen the support of the widened section of the machine roadway; Step 4: Monitoring and adaptation of ventilation and transportation during the working face turning period.

2. The method for adjusting and turning the length of an irregularly shaped coal mining face according to claim 1, characterized in that, The specific process of step 1 is as follows: Step 11: Determine the inflection point of the working face. When the working face turns, the center point of the machine roadway on the side closest to the center of the turning circle is the inflection point. The machine roadway is divided into the roadway before the turn and the roadway after the turn. Step 12: Determine the length of the centerline of the bridge transfer machine when it is retracted to its shortest length, based on the model of the bridge transfer machine used on the working face; Step 13: Draw a reference circle with the determined inflection point as the center; Step 14: Draw the starting line and ending line of the working face turning, and the intersection of the starting line and the ending line of the working face turning is the center of the turning circle; Step 15: Determine the widening range and degree of the machine roadway based on the starting line and stopping line of the working face turning; Step 16: With the center of the turning circle as the vertex, and the starting line and the stopping line of the working face turning as the two sides, form an angle. Draw a bisector of the angle. The bisector intersects the inner line of the roadway before turning and the inner line of the roadway after turning. The distance between two adjacent bisectors is the advancing distance during the working face turning process. Step 17: Divide the working face into equal sections based on the actual coal cutting advance as the basic unit. Determine the pushing distance ratio at both ends of the working face during the turning process based on the similarity ratio of each equal triangle.

3. The method for adjusting and turning the length of an irregularly shaped coal mining face according to claim 2, characterized in that, In step 13, let the intersection of the reference circle and the center line of the roadway before the turn be s1, and the intersection of the reference circle and the center line of the roadway after the turn be s2. Let the straight-line distance between s1 and s2 be d1, then d1 = d2, and d2 is the length of the centerline when the bridge transfer machine is contracted to its shortest length.

4. The method for adjusting and turning the length of an irregularly shaped coal mining face according to claim 3, characterized in that, In step 14, a straight line parallel to the working face before turning is drawn through the intersection point s1 of the reference circle and the center line of the roadway before turning, which is the starting line of the working face turning; a straight line parallel to the working face after turning is drawn through the intersection point s2 of the reference circle and the center line of the roadway after turning, which is the stopping line of the working face turning; the starting line of the working face turning and the stopping line of the working face turning are both tangent to the reference circle.

5. The method for adjusting and turning the length of an irregularly shaped coal mining face according to claim 4, characterized in that, In step 15, the area of ​​the intersection of the working face turning start line, the working face turning stop line and the outer line of the machine lane where the inflection point is located is used as the machine lane widening range for machine lane widening; the boundary line of the machine lane after widening is parallel to the line connecting s1 and s2, and the vertical distance between the inflection point and the boundary line of the machine lane after widening is half the width of the machine lane where the inflection point is located.

6. The method for adjusting and turning the length of an irregularly shaped coal mining face according to claim 5, characterized in that, In step 2, a hydraulic cylinder is installed between the top beam and the base body of two adjacent hydraulic supports. The hydraulic cylinder between the two top beams is called the top cylinder, and the hydraulic cylinder between the two base bodies is called the bottom cylinder. The center lines of the top cylinder and the bottom cylinder on the same support are on the same vertical plane to ensure that the hydraulic support is pushed synchronously and coordinated during the turning process.

7. The method for adjusting and turning the length of an irregularly shaped coal mining face according to claim 6, characterized in that, In step 2, during the turning process of the working face, the top cylinder and the bottom cylinder extend and retract simultaneously, coordinating to control the turning of the hydraulic support, so that the hydraulic support is always perpendicular to the working face.

8. The method for adjusting and turning the length of an irregularly shaped coal mining face according to claim 7, characterized in that, In step 3, local reinforcement support is required at the widened section of the machine roadway. The support method is determined based on the roof span, lithology, ground stress, and mining impact conditions at the widened section of the machine roadway.

9. The method for adjusting and turning the length of an irregularly shaped coal mining face according to claim 8, characterized in that, In step 4, during the turning process of the working face, both the roadway before and after the turning are involved in the turning, and the turning point also involves the widening of the machine roadway. The working face equipment continuously adjusts its orientation during the turning process. Therefore, the ventilation resistance and transportation capacity of the working face and the mining roadways on both sides are calculated and adjusted in real time. At the same time, the gas concentration monitoring at the turning point is strengthened to ensure the safe mining of the working face.

10. The method for adjusting and turning the length of an irregularly shaped coal mining face according to claim 9, characterized in that, When the working face advances to the turning range, the advance support of the working face is moved to both sides of the machine roadway in advance to ensure that the hydraulic support frame and the bridge transfer machine can pass through; at the same time, the length of the bridge transfer machine is shortened to the minimum to ensure that the working face can pass through the turning point when turning.

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