An automatic and precise pressure control device for grouting anchor rod

Abstract

The present invention relates to an automatic and precise pressure control device for grouting anchor rods, comprising an upper clamp, a lower clamp, a bursting disc, a spring, a metal block and a high-pressure resistant metal pipe. The high-pressure resistant metal pipes on both sides of the device can be fixed on the grouting pipeline by quick plugging. When the grouting pressure in the pipeline is greater than the preset value of the bursting disc, the bursting disc is torn apart along the supporting edge and falls off as a whole. The spring returns to its original state, thereby pushing the metal block and the fallen bursting disc into the groove of the lower clamp, preventing the slurry from continuing to flow. The device realizes automatic pressure control, solves the problem that the grouting anchor rod (cable) is overly dependent on manual judgment of the grouting situation, effectively improves the effect of automatic and precise control of the grouting pressure, and ensures the safety of the grouting process.

Description

Technical Field

[0001] The invention belongs to the technical field of mine anchor equipment, and in particular relates to an automatic and precise pressure control device for a grouting anchor. Background Art

[0002] With the continuous development of my country's coal industry, anchor (cable) support technology has reached more than 90% in coal mine tunnel support. However, there are still many safety hazards when constructing in underground tunnels under complex geological conditions, mainly roof falls and collapse accidents. Anchor-injection support technology converts grouting anchors (cables) into full-length anchors, fills the cracks in the surrounding rock, integrates the broken surrounding rock, and significantly improves the integrity and mechanical properties of the surrounding rock. A large number of engineering practices have shown that anchor-injection support technology is an effective measure to maintain the stability of the tunnel surrounding rock and reduce roof falls.

[0003] When grouting is performed to reinforce the surrounding rock cracks, the grouting pressure is generally used as a sign of whether the grouting is completed. It is necessary to monitor the grouting pressure, shut down the grouting pump in time, and stop the grouting. The existing grouting pressure monitoring technology mainly relies on the pressure gauge on the grouting pump for manual judgment and identification. In the actual grouting process, due to the complex underground environment, manual judgment often has large errors. Stopping when the pressure is too low will result in insufficient grouting and poor grouting effect; excessive pressure will lead to leakage, grouting and other phenomena, and even cause safety accidents. Summary of the invention

[0004] In order to effectively solve the problem that traditional grouting stopping methods rely too much on manual judgment, the present invention designs an automatic and precise pressure control device for grouting anchor rods, which is particularly suitable for timely stopping grouting when the grouting pressure of anchor support in mine shafts, tunnels and underground projects is too high, thereby achieving safe and efficient grouting.

[0005] In order to achieve the above-mentioned purpose, the technical solution adopted by the present invention is: an automatic precise pressure control device for grouting anchor rods, comprising an upper clamp, a lower clamp, a bursting disc, a spring, a metal block and a high-pressure resistant metal pipe, wherein

[0006] The upper clamp and the lower clamp are both made of high-pressure resistant metal and are designed as a rectangular parallelepiped. The lower end of the upper clamp and the upper end of the lower clamp are provided with square openings, and the two are fastened by bolts at four corners; a small square opening is opened on one side of the upper clamp; a groove is designed at the bottom of the lower clamp for fixing the fallen bursting disc and metal block, and a circular hole is opened on the left and right sides respectively, and an inner thread is designed in the hole to cooperate with the outer thread of the high-pressure resistant metal tube;

[0007] The rupture disc is a rectangular flat-plate detachable rupture disc, which is installed on the top of the lower holder and forms a slurry flow pipeline with the lower holder; when the grouting pressure in the pipeline is greater than the preset value of the rupture disc, the rupture disc is torn along the support edge and falls off as a whole;

[0008] The spring is a cylindrical compression spring, and its main function is that when the bursting disc falls off, the spring returns to its original shape, thereby pushing the metal block and the fallen bursting disc into the groove of the lower holder, preventing the slurry from continuing to flow;

[0009] The metal block is a solid rectangular parallelepiped, and its size fits the interior of the upper holder. When the bursting disc falls off, the metal block quickly falls into the groove of the lower holder under the action of its own gravity and the spring, blocking the grouting pipeline and preventing the slurry from flowing.

[0010] The high-pressure resistant metal pipe is a slurry circulation pipeline, and an outer thread is arranged on the outer side of the pipeline, which is consistent with the inner thread width of the circular openings on both sides of the lower clamp and cooperates with each other.

[0011] Furthermore, the upper clamp and the lower clamp can provide sufficient pressing force to ensure the sealing performance of the entire device.

[0012] Furthermore, the bursting disc does not generate fragments after falling off, has a large effective discharge area, and has good fatigue resistance.

[0013] Furthermore, the size of the metal block matches the groove of the lower clamp, and there is no obvious gap around it when it falls into the groove of the lower clamp.

[0014] Furthermore, the high-pressure resistant metal pipes on both sides of the device can be fixed on the grouting pipeline by quick plugs.

[0015] The beneficial effects of the present invention are:

[0016] 1) Use a bursting disc to achieve automatic and precise pressure control. The bursting disc is a device that automatically releases pressure by rupturing the bursting disc due to the pressure difference between the inlet and outlet media. When the pressure difference on both sides of the bursting disc reaches a predetermined value at the set bursting temperature, the bursting disc will immediately act to release the pressure in time;

[0017] 2) The device has a simple structure and reliable performance. It can respond quickly and stop grouting when the grouting pressure is too high, thus achieving safe and efficient grouting.

[0018] 3) This device has a more accurate effect and a more convenient installation method than the traditional grouting pressure monitoring method. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0020] Figure 1 It is a cross-sectional view of an automatic precise pressure control device for grouting anchor before the bursting piece falls off.

[0021] The reference numerals are described as follows:

[0022] 1. Upper clamp; 2. Lower clamp; 3. Spring; 4. Metal block; 5. Bolt; 6. Bursting disc; 7. High-pressure resistant metal pipe; 8. Cement slurry. DETAILED DESCRIPTION

[0023] The preferred embodiments of the present invention are described in detail below in conjunction with the accompanying drawings so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby making a clearer and more definite definition of the protection scope of the present invention.

[0024] like Figure 1 As shown, a grouting anchor bolt automatic precision pressure control device includes an upper clamp, a lower clamp, a bursting disc, a spring, a metal block and a high-pressure resistant metal pipe, wherein

[0025] The upper clamp and the lower clamp are both made of high-pressure resistant metal, and the two are fastened by bolts at the four corners, which can provide sufficient clamping force to ensure the sealing performance of the entire device. The upper and lower clamps are designed as rectangular parallelepipeds for easy twisting. A square opening is provided at the lower end of the upper clamp and the upper end of the lower clamp to facilitate the movement of the metal block in the clamp. A small square opening is also provided on one side of the upper clamp, through which the underground grouting construction personnel can observe whether the metal block falls into the lower clamp, so as to judge the time to shut down the grouting pump. A circular hole is provided on the left and right sides of the lower clamp, respectively, and an inner thread is designed in the hole to cooperate with the outer thread of the high-pressure resistant metal tube. A groove is designed at the bottom of the lower clamp to fix the fallen blasting disc and metal block.

[0026] The spring is a cylindrical compression spring, and its main function is to restore itself to its original shape when the bursting disc falls off, thereby pushing the metal block and the fallen bursting disc into the groove of the lower clamp to prevent the slurry from continuing to flow.

[0027] The bursting disc is a device that automatically releases pressure by rupturing the bursting disc under the pressure difference between the inlet and outlet media. When the pressure difference on both sides of the bursting disc reaches a predetermined value at the set bursting temperature, the bursting disc will immediately act to release the pressure medium in time. The bursting disc of this device adopts a rectangular flat-plate detachable bursting disc. When the grouting pressure in the pipeline is greater than the predetermined value of the bursting disc, the bursting disc will tear along the supporting edge and fall off as a whole. The advantages of this bursting disc are that it does not produce fragments after falling off, has a large effective discharge area, is suitable for most occasions, and has good fatigue resistance.

[0028] The metal block is a solid cuboid, made of high-pressure resistant metal material, and its size fits the inside of the holder. After the metal block is placed in the holder, there is no obvious gap around it. When the bursting disc falls off, the metal block quickly falls into the groove of the lower holder under the action of its own gravity and the spring, blocking the grouting pipeline, preventing the slurry from flowing, and completing the pressure control.

[0029] The high-pressure metal pipe is a slurry flow pipeline, and an outer thread is arranged on the outer side of one end of the pipe, which cooperates with the inner threads of the circular openings on both sides of the lower clamp. The width of the outer thread is consistent with that of the inner thread, and when the metal pipe is fully screwed in, it will not block the metal block and the bursting disc from falling.

[0030] The specific use steps of an automatic precise pressure control device for grouting anchor rods (cables) are as follows:

[0031] Step 1. Put the spring and metal block into the lower opening of the upper clamp in sequence, first the spring and then the metal block.

[0032] Step 2. Connect the four corners of the upper clamp, bursting disc and lower clamp through nuts to provide a certain compression force and sealing. Then fasten the high-pressure metal pipes on both sides of the device to the device through threads. Raw tape can be used to assist in installation to enhance the airtightness of the pipe interface and prevent leakage.

[0033] Step 3. Fix the high-pressure metal pipes on both sides of the device to the grouting pipeline through quick plugs, and start the grouting pump for grouting. When the grouting pressure in the pipeline is greater than the preset value of the bursting disc, the bursting disc will fall off immediately. From the side opening of the device, it can be seen that the spring quickly recovers from the compressed state, and at the same time, the metal block and the fallen bursting disc are pushed into the groove of the lower clamp. The metal block blocks the grouting pipeline, preventing the slurry from continuing to be injected into the coal rock body, and completing the automatic and precise control of the grouting pressure.

[0034] The above is only an embodiment of the present invention, and the common knowledge such as the known specific structure and characteristics in the scheme is not described in detail here. It should be pointed out that for those skilled in the art, several modifications and improvements can be made without departing from the structure of the present invention, which should also be regarded as the protection scope of the present invention, and these will not affect the effect of the implementation of the present invention and the practicality of the present invention.

Claims

1. An automatic precise pressure control device for grouting anchor, comprising an upper clamp, a lower clamp, a bursting disc, a spring, a metal block and a high-pressure resistant metal pipe, wherein The upper clamp and the lower clamp are both made of high-pressure resistant metal and are designed as a rectangular parallelepiped. The lower end of the upper clamp and the upper end of the lower clamp are provided with square openings, and the two are fastened by bolts at four corners; a small square opening is opened on one side of the upper clamp; a groove is designed at the bottom of the lower clamp for fixing the fallen bursting disc and metal block, and a circular hole is opened on the left and right sides respectively, and an inner thread is designed in the hole to cooperate with the outer thread of the high-pressure resistant metal tube; The rupture disc is a rectangular flat-plate detachable rupture disc, which is installed on the top of the lower holder and forms a slurry flow pipeline with the lower holder; when the grouting pressure in the pipeline is greater than the preset value of the rupture disc, the rupture disc is torn along the support edge and falls off as a whole; The spring is a cylindrical compression spring, and its main function is that when the bursting disc falls off, the spring returns to its original shape, thereby pushing the metal block and the fallen bursting disc into the groove of the lower holder, preventing the slurry from continuing to flow; The metal block is a solid rectangular parallelepiped, and its size fits the interior of the upper holder. When the bursting disc falls off, the metal block quickly falls into the groove of the lower holder under the action of its own gravity and the spring, blocking the grouting pipeline and preventing the slurry from flowing. The high-pressure resistant metal pipe is a slurry circulation pipeline, and an outer thread is arranged on the outer side of the pipeline, which is consistent with the inner thread width of the circular openings on both sides of the lower clamp and cooperates with each other.

2. The automatic and precise pressure control device for grouting anchor rod according to claim 1 is characterized in that: The upper clamp and the lower clamp can provide sufficient pressing force to ensure the sealing performance of the entire device.

3. The automatic and precise pressure control device for grouting anchor rod according to claim 1 is characterized in that: The bursting disc does not generate fragments after falling off, has a large effective discharge area, and has good fatigue resistance.

4. The automatic and precise pressure control device for grouting anchor rod according to claim 1 is characterized in that: The size of the metal block matches the groove of the lower clamp, and there is no obvious gap around it when it falls into the groove of the lower clamp.

5. The automatic and precise pressure control device for grouting anchor rod according to claim 1 is characterized in that: The high-pressure resistant metal pipes on both sides of the device can be fixed on the grouting pipeline by quick plugs.

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