CN118149692A - Sensor for detecting bending of drill rod and drill rod thrust control method - Google Patents

Abstract

The invention relates to a bending detection device, in particular to a sensor for detecting bending of a drill rod and a drill rod thrust control method. The sensor comprises a main body, fixed arms and sliding arms on two sides, wherein the outer ends of the sliding arms are contacted with the side wall of the drill rod, and a distance measuring device is arranged at the inner end of the sliding arms. And the bending degree of the drill rod is calculated through the sensing of the sensor on the transverse movement amount of the drill rod, so that the proper output thrust is controlled.

Description

A sensor for detecting drill rod bending and a drill rod thrust control method

Technical Field

The invention relates to a bending detection device, in particular to a sensor for detecting the bending of a drill rod and a method for controlling the thrust of the drill rod.

Background technique

At present, pneumatic anchor drills, hydraulic anchor drills, and hydraulic anchor drill vehicles are used in coal mines. They can be used to support and drill holes in coal tunnels and rock tunnels with various rock hardnesses of f≤10, anchors, and anchor cables. They have outstanding advantages in improving support effects, reducing costs, speeding up tunneling, reducing auxiliary transportation, reducing labor intensity, and improving tunnel section utilization. Anchor drills are key equipment for anchor support, which affects the quality of anchor support: the orientation, depth, and accuracy of the aperture of the anchor hole, as well as the quality of anchor installation, and also involve the operator's personal safety, labor intensity, and working conditions.

When the anchor drill is drilling, its maximum thrust is generally determined by the material, structure, and hardness of the anchor, and is currently calculated using theory. In order to ensure safety during drilling, theoretical calculations are very conservative, which greatly affects drilling efficiency. Currently, there are optical detection devices, mechanical contact detection devices, ultrasonic detection devices, laser scanning devices, digital image processing systems, etc., but these detection devices all require the drill rod to be removed from the drilling rig for detection, and cannot perform real-time detection of the running drill rod.

Summary of the invention

In view of the deficiencies in the prior art, the present invention provides a sensor which has a simple structure, is easy to install, and can detect the bending of a drill rod in real time during the drilling process, and a drill rod thrust control method using the sensor.

The technical solution adopted by the present invention is: a sensor for detecting the bending of a drill rod, comprising a sensor body, wherein two sides of the sensor body are respectively connected to a drilling rig and a drill rod, wherein a fixed arm and a movable arm are arranged on one side connected to the drill rod, the movable arm is inserted into a sliding hole of the fixed arm, the movable arm is away from the fixed arm and is in contact with the side wall of the drill rod, a spring is provided on the movable arm sleeve, a limiting ring is arranged on the end of the movable arm close to the drill rod, two ends of the spring respectively abut against the end face of the fixed arm and the limiting ring, when the drill rod is not bent or is bent, the movable arm always keeps in contact with the side wall of the drill rod under the action of the spring, and a distance sensing device for sensing the sliding distance of the movable arm in the sliding hole is arranged in the fixed arm.

Furthermore, two guide seats are provided at one end of the sensor body connected to the drill rod, and a guide groove is formed between the two guide seats.

Furthermore, there are two sets of fixed arms and movable arms, which are symmetrically arranged on both sides of the drill pipe.

Furthermore, the distance sensing device includes a resistor and a sliding contact, and the resistor is installed in the fixed arm and arranged in parallel with the sliding hole.

Furthermore, the fixed arm and the movable arm are both arc structures.

A drill pipe thrust control method comprises the following steps:

Step 1: Measure the extension length l of the drill rod and the extension length x of the contact position between the drill rod and the movable arm, and set the limit bending degree of the drill rod;

Step 2: Start the drilling rig to perform drilling operations, and monitor the displacement of the movable arms on both sides in the sliding hole in real time. When displacement occurs, the bending of the drill pipe is calculated by the displacement d of the movable arm on one side that is retracted, and the thrust of the drilling rig is adjusted according to the difference between the bending and the limit bending.

Furthermore, step two also includes: also detecting the displacement of the movable arm on the extended side, setting a displacement deviation limit, and when the displacement deviation between the movable arm on the retracted side and the movable arm on the extended side is higher than the displacement deviation limit, the system issues an alarm.

The present invention can detect the bending curvature of the drill rod in real time during the drilling operation, thereby realizing closed-loop control of the anchor rod thrust to maximize its efficiency, while preventing the anchor rod from excessively bending and causing harm to workers, and the like.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a schematic diagram of the main structure of the sensor of the present invention;

FIG2 is a schematic diagram of the left side structure of the sensor of the present invention;

FIG3 is a schematic diagram of the structure of the sensor of the present invention from top view;

FIG4 is a schematic diagram of the structure of the sensor of the present invention when viewed from above;

FIG5 is a schematic diagram of the three-dimensional structure of the sensor of the present invention;

FIG6 is a schematic diagram of the internal structure of the fixed arm of the present invention;

FIG. 7 is a diagram showing the principle of calculating the curvature of a drill pipe according to the present invention.

In the figure: 1-sensor body, 11-docking installation part, 12-drill rod insertion part, 13-drill rod guide part, 14-water hole, 15-fixed arm, 16-movable arm,

111 - electrical connection hole, 121 - drill rod mounting hole, 131 - guide seat, 132 - guide groove, 151 - sliding hole, 152 - resistor, 153 - sliding contact, 161 - spring, 162 - limit ring.

Detailed ways

As shown in Fig. 1-5, a sensor for detecting drill rod bending includes a sensor body 1. The sensor body 1 is installed between a drilling rig and a drill rod, that is, the sensor body 1 is connected to the drill rod and the drilling rig on both sides, and the sensor body 1 is composed of a connecting installation part 11, a drill rod insertion part 12, and a drill rod guide part 13 in the direction from the drilling rig to the drill rod.

The docking installation part 11 is docked with the power output shaft of the drilling rig through a through-hole conductive slip ring to ensure power supply and signal input and output when the sensor and the drill rod rotate. A water hole 14 and an electrical connection hole 111 are opened at the bottom of the docking installation part 11.

The drill rod mounting portion 12 is provided with a drill rod mounting hole 121 facing the drilling direction. In this embodiment, the cross section of the drill rod is a regular hexagon, so the drill rod mounting hole 121 is adapted to the shape of the drill rod. The water hole 14 passes through the sensor body 1 and is connected to the drill rod mounting hole 121.

The drill rod guide portion 13 includes two guide seats 131 , which are symmetrically arranged with a guide groove 132 formed therebetween. The drill rod installed in the drill rod installation hole 121 passes through the guide groove 132 and extends forward.

As shown in Figures 1, 3, 5 and 6, two groups of fixed arms 15 and movable arms 16 are symmetrically arranged on one side of the sensor body 1 for mounting the drill rod. Both the fixed arm 15 and the movable arm 16 are arc-shaped structures. A sliding hole 151 is arranged in the fixed arm 15, and the movable arm 16 is inserted into the sliding hole 151. The plane where the fixed arm 15 and the movable arm 16 slide and extend in the direction coincides with the center plane of the extension direction of the guide groove 132, and passes through the center axis of the drill rod.

The movable arm 16 is provided with a spring 161, and a limit ring 162 is provided near one end of the drill rod. Both ends of the spring 161 respectively abut against the end surface of the fixed arm 15 and the limit ring 162. When the drill rod is not bent or is bent, the movable arm 16 always keeps in contact with the side wall of the drill rod under the action of the spring 161. The outer end surface of the movable arm 16 is provided with an end surface adapted to fit the side wall of the drill rod. The movable arm 16 is located at the inner end side of the sliding hole 151 and a sliding contact 153 is installed. A resistor 152 with an arc structure parallel to the sliding hole 151 is provided in the fixed arm 15. When the movable arm 16 slides, the sliding contact 153 moves synchronously on the resistor 152.

Before drilling, first measure the extension length l of the drill rod and the extension length x of the contact position between the drill rod and the movable arm 16, and reset the displacement of the movable arms 16 on both sides. Determine the bending limit of the drill rod against pressure based on its material and structural information.

When drilling, the drill rod rotates synchronously with the sensor. Under the thrust of the drill rig, the drill rod bends slightly. Since the end of the drill rod is in the guide groove 132, its bending is plane bending, and the spiral bending can be ignored. When the drill rod bends, the movable arm 16 on the bending side slides and retracts under the external force, the position of the sliding contact 153 on the resistor 152 changes, and the resistor changes. The control system calculates the displacement d or the sliding angle α of the movable arm 16 through the change of the resistance value. Since x is a known number, the lateral movement distance of the drill rod at the contact position with the movable arm 16 can be calculated by trigonometric functions, and then the total length l of the drill rod is used to finally calculate the curvature of the drill rod through the curve equation. When the curvature is extremely small and far below the bending limit, the system increases the thrust of the drill rod. When the curvature increases and approaches the limit value, the system reduces the pressure value. Finally, under PID regulation, a reasonable thrust range is maintained to maximize the drilling efficiency without damaging the drill rod.

At the same time, the displacement of the movable arm 16 on the extended side is detected, and a displacement deviation limit is set. When the displacement deviation between the movable arm 16 on the retracted side and the movable arm 16 on the extended side is higher than the displacement deviation limit, the system issues an alarm.

Some structures in the above embodiments can be replaced by equivalent ones: 1. The fixed arm 15 and the movable arm 16 are set as an arc structure mainly because the radial space occupied by the structure is small. If other telescopic structures are used, the detection function can also be realized. 2. The movable arm 16 is kept in contact with the drill rod under the action of the spring. If other elastic structures are used to control it to always be in contact with the drill rod, it is also acceptable. Therefore, the equivalent replacement of the above two structures also belongs to the protection scope of the present invention.

Claims (7)

1. The utility model provides a detect crooked sensor of drilling rod, includes sensor main part (1), characterized by: the drilling machine is characterized in that two sides of the sensor main body (1) are respectively connected with the drilling machine and the drill rod, a fixed arm (15) and a movable arm (16) are arranged on one side of the drill rod, the movable arm (16) is inserted into a sliding hole (151) of the fixed arm (15), one end of the movable arm (16) is far away from the fixed arm (15) and is attached to the side wall of the drill rod, a spring (161) is sleeved on the movable arm (16), a limiting ring table (162) is arranged on one end, close to the drill rod, of the movable arm (16), two ends of the spring (161) are respectively abutted to the end face of the fixed arm (15) and the limiting ring table (162), and when the drill rod is not bent or is bent, the movable arm (16) is always attached to the side wall of the drill rod under the action of the spring (161), and a distance sensing device for sensing the sliding distance of the movable arm (16) in the sliding hole (151) is arranged in the fixed arm (15).

2. A sensor for detecting bending of a drill rod as recited in claim 1, wherein: two guide seats (131) are arranged at one end, connected with the drill rod, of the sensor main body (1), and a guide groove (132) is formed between the two guide seats (131).

3. A sensor for detecting bending of a drill rod as recited in claim 2, wherein: the number of the fixed arms (15) and the movable arms (16) is 2, and the fixed arms and the movable arms are symmetrically arranged on two sides of the drill rod.

4. A sensor for detecting bending of a drill rod as claimed in claim 1,2 or 3, wherein: the distance sensing device comprises a resistor (152) and a sliding contact (153), wherein the resistor (152) is installed in the fixed arm (15) and is arranged in parallel with the sliding hole (151).

5. A sensor for detecting bending of a drill rod as claimed in claim 1,2 or 3, wherein: the fixed arm (15) and the movable arm (16) are of arc structures.

6. A drill rod thrust control method employing a sensor for detecting bending of a drill rod as claimed in claim 3, characterized in that; comprises the following steps:

step one: measuring the extension length l of the drill rod and the extension length x of the contact position of the drill rod and the movable arm (16), and setting the limit curvature of the drill rod;

step two: and starting the drilling machine to perform drilling operation, monitoring the displacement of the movable arms (16) at two sides in the sliding hole (151) in real time, calculating the curvature of the drill rod through the displacement d of the movable arm (16) at one side to retract when the displacement occurs, and adjusting the thrust of the drilling machine according to the difference between the curvature and the limit curvature.

7. The drill pipe thrust control method of claim 6, wherein the method comprises the following steps: the second step further comprises: and detecting the displacement of the movable arm (16) at the extending side, setting a displacement deviation limit, and sending an alarm prompt by the system when the displacement deviation of the movable arm (16) at the retracting side and the movable arm (16) at the extending side is higher than the displacement deviation limit.