CN109751402B - Vehicle-mounted coalbed methane drill power head reduction gearbox - Google Patents

Abstract

The application discloses a vehicle-mounted coalbed methane drill head reduction gearbox which comprises a box body, a box cover, a main shaft, a driven gear and a detachable and replaceable slurry sealing device, wherein the box body is provided with a box cover and a box cover; the slurry sealing device is coaxial with the main shaft and is arranged on the upper end surface of the main shaft and used for sealing high-pressure slurry in the hollow main shaft; the slurry sealing device comprises a wear-resistant pipe, a static sealing structure and a dynamic sealing structure; the abrasion-resistant pipe is fixedly connected with the static sealing structure, the dynamic sealing structure is fixedly connected to the upper end of the main shaft, the dynamic sealing structure is rotationally connected with the abrasion-resistant pipe, and in the drilling operation process, the main shaft drives the dynamic sealing structure to rotate around the abrasion-resistant pipe of the static sealing structure, so that high-pressure slurry at the rotating/non-rotating position is sealed. The support cylinder is provided with an installation opening for taking and placing the slurry sealing device, so that the slurry sealing device is convenient to replace. The three groups of bearings are adopted to respectively transmit the torsion, lifting force and downward pressure during working, and the structure is simple and practical.

Description

A vehicle-mounted coal bed methane drilling rig power head reduction gearbox

Technical field

The invention belongs to the technical field of engineering equipment and relates to a power head reduction gearbox for a vehicle-mounted coal bed methane drilling rig.

Background technique

Compared with traditional vertical shaft and rotary table drilling rigs, truck-mounted coal bed methane drilling rigs using fully hydraulic power heads have significantly improved working performance and efficiency, and have developed rapidly in the domestic market in recent years.

The existing technology has the following defects: 1. It cannot achieve good sealing inside the power head to prevent high-pressure mud from leaking from the rotating/non-rotating position of the upper end of the main shaft of the power head, causing the power head to be scrapped; 2. The existing seal The device is a non-independent module. Replacing the seals needs to be done on the entire drilling rig. It is necessary to remove the connecting flange at the top and the mud pipelines on it, etc., and then remove the wear-resistant pipe assembly. The disassembly process is time-consuming. Effortless.

Contents of the invention

Purpose: In order to overcome the deficiencies in the prior art, the present invention provides a vehicle-mounted coal bed methane drilling rig power head reduction gearbox. It has a simple structure and has a self-sealing and modular sealing device. While achieving effective sealing, the seals can be replaced quickly and easily, greatly improving operating efficiency.

Technical solution: In order to solve the above technical problems, the technical solution adopted by the present invention is:

A power head reduction gearbox, including a box body, a box cover, a main shaft, a driven gear and a removable and replaceable mud sealing device;

A main shaft for outputting power from the reduction box is rotatably assembled in the box, and the driven gear is coaxially fixed with the main shaft to transmit rotational power to the main shaft;

The mud sealing device is coaxial with the main shaft and installed on the upper end surface of the main shaft, and is used to seal the high-pressure mud in the hollow main shaft;

The mud sealing device includes a wear-resistant tube, a static sealing structure and a dynamic sealing structure; the wear-resistant tube is fixedly connected to the static sealing structure, the dynamic sealing structure is fixedly connected to the upper end of the main shaft, and the dynamic sealing structure is connected to the upper end of the spindle. The wear-resistant tube is rotatably connected. During the drilling operation, the spindle drives the dynamic sealing structure to rotate around the wear-resistant tube of the static sealing structure, thereby sealing the high-pressure mud in the rotating/non-rotating position.

The box cover is removably and fixedly connected to the upper end surface of the box body; a support tube coaxial with the main shaft is fixedly connected to the box cover; the support tube is a cylindrical structure, and a hole is provided on the support tube for Access the installation opening of the mud seal device.

The mud sealing device has a self-sealing, modular structure, and its upper and lower ends are trapezoidal threads, which can be fixedly connected with the upper end of the main shaft and the inner inner threads of the upper end of the support tube respectively. When it is necessary to replace the internal sealing member of the mud sealing device, simply loosen the thread, and the mud sealing device can be taken out from the installation port on the support tube.

Further, the static sealing structure includes an upper packing box gland, a first O-ring, an upper sealing sleeve, packing, a retaining ring, and an upper packing box; the upper packing box gland is threadedly connected and installed on the On the inner side of the upper end of the support tube, the packing and the upper sealing sleeve are installed in the upper packing box in sequence. The wear-resistant pipe and the upper sealing sleeve are circumferentially connected by rectangular splines, and the retaining ring is installed in the annular groove of the wear-resistant pipe. , to prevent the wear-resistant pipe from falling from the static sealing structure; the first O-ring is installed in the upper end ring groove of the upper sealing sleeve, and forms an end face static seal with the end face of the support tube.

Further, the dynamic sealing structure includes packing, a lower packing box, a lower sealing sleeve, a lower packing box gland, a second O-ring, screws, and an oil cup; the lower packing box gland is threaded for installation. At the upper end of the main shaft, the packing and the lower sealing sleeve are installed in the lower packing box in sequence. The oil cup is installed on the lower packing box for regular lubrication of the dynamic sealing structure. The screw circumference is installed on the lower packing box and snapped into The annular groove of the lower sealing gland prevents the packing and the lower sealing gland from falling out of the lower packing box during the assembly process; the second O-ring is installed in the end annular groove of the lower sealing gland and is in contact with the main shaft. The end face forms an end face static seal.

In the above-mentioned static sealing structure and dynamic sealing structure, the number of packings can be adjusted according to needs. It can be one or more, and spacers are provided between multiple packings.

After the truck-mounted coal bed methane drilling rig has been working for a period of time, the packing will wear to a certain extent, resulting in a decrease in sealing performance. At this time, the compression amount of the packing can be adjusted by tightening the upper packing box gland and the lower packing box gland in sequence to improve The service life of static sealing structure and dynamic sealing structure.

As a preferred solution, the power head reduction gearbox further includes a first bearing. The first bearing is fixedly installed between the main shaft and the box cover. The box cover is provided with a first bearing seat. The inner ring of a bearing is fixedly connected to the main shaft, and the outer ring of the first bearing is clamped and fixed on the first bearing seat inside the box cover; the box cover is used to bear the torsion during operation to straighten the main shaft and improve rotation stability. sex;

It also includes a second bearing, which is fixedly installed in the middle and upper part between the main shaft and the box body, and the driven gear is close to the top of the second bearing. The second bearing is installed in the middle and upper part of the box body. Bearing seat, the inner ring of the second bearing is fixedly connected to the main shaft, and the outer ring of the second bearing is clamped and fixed on the second bearing seat inside the box; so as to bear the direction of the drilling tool installed on the main shaft through the box. downward pulling force;

It also includes a third bearing, which is fixedly installed in the lower part between the main shaft and the box body. A third bearing seat is provided in the lower part of the box body. The inner ring of the third bearing is fixed to the main shaft. The outer ring of the third bearing is clamped and fixed to the third bearing seat inside the box body; the box body is used to withstand the upward pressure of the drilling tool installed on the main shaft.

The power head reduction gearbox also includes a hydraulic motor, which provides power for the rotation of the main shaft. A speed change transmission mechanism is provided between the main shaft and the hydraulic motor. The speed change transmission mechanism includes a transmission mechanism connected to the hydraulic motor. The motor output shaft has a driving gear coaxially connected to the main shaft and a driven gear coaxially connected to the main shaft. The driving gear meshes with the driven gear. The driving gear and the driven gear are located in the box. middle.

Further, the main shaft is equipped with a pressure plate for compressing the driven gear. The pressure plate is threadedly connected to the outer wall of the main shaft. In the direction of the main shaft axis, the pressure plate and the driven gear are fixed with bolts. connection to prevent the driven gear from moving axially;

Further, the hydraulic motor is connected and installed on the box cover, and the hydraulic motor is installed parallel to the main shaft.

The power head reduction gearbox also includes an upper sealing structure and a lower sealing structure. The upper sealing structure and the lower sealing structure are coaxial with the main shaft and are respectively installed at the upper end and lower end of the box for sealing the box. gear oil in.

As a preferred solution, an upper sealing structure is provided on the upper end of the first bearing, and the upper sealing structure includes a bearing cover plate, a first skeleton oil seal, a first spacer, a fourth O-ring, and a third O-ring;

The bearing cover and the box cover are connected with bolts to compress the first bearing; the bearing cover is equipped with two sets of first skeleton oil seals installed back to back, which on the one hand prevents external mud or dust from entering the reduction box The gear oil in the body is polluted, and on the other hand, the internal gear oil is prevented from seeping out; the third O-ring seal is used between the bearing cover and the box cover to prevent the gear oil in the reduction box from seeping out between them;

Further, a first spacer sleeve is provided between the first skeleton oil seal and the main shaft, thereby converting the relative rotation seal between the main shaft and the first skeleton oil seal into the relative rotation seal between the first spacer sleeve and the first skeleton oil seal. ;The first spacer sleeve and the main shaft are tightly fitted and connected,

More preferably, a fourth O-ring is provided between the first spacer sleeve and the main shaft to prevent the gear oil in the reduction box from seeping out between them.

Further, a mud umbrella is installed on the main shaft above the bearing cover.

As a preferred solution, a mud leakage port is provided on the support tube so that when mud leakage occurs, the mud flows out from the mud leakage port, thereby extending the life of the first skeleton oil seal and preventing the mud from flowing from the bearing cover plate to the bearing cover plate. The first partition room enters the reduction box body.

As a preferred solution, the power head reduction gearbox is characterized in that: the lower end of the box body is provided with a lower sealing structure, and the lower sealing structure includes a lower end cover, a fifth O-shaped sealing ring, a second skeleton oil seal, and a felt ring. ;

The lower end cover is connected to the box body with bolts, and two sets of second skeleton oil seals installed in the same direction are installed on the lower end cover to seal the gear oil in the reduction box; a fifth set of oil seals is used between the lower end cover and the box body. The O-ring seal prevents the gear oil in the reduction box from seeping out between them; the lower end cover is equipped with a felt ring to prevent external mud or dust from entering the reduction box and contaminating the gear oil.

Further, a second spacer sleeve is provided between the second skeleton oil seal and the main shaft, thereby converting the relative rotation of the seal between the main shaft and the second skeleton oil seal into the relative rotation of the second spacer sleeve and the second skeleton oil seal. Sealing; the second spacer sleeve is tightly connected to the main shaft;

More preferably, a sixth O-ring is provided between the second spacer sleeve and the main shaft to prevent the gear oil in the reduction box from seeping out between them.

As a preferred solution, in the power head reduction box, a magnetic screw plug is installed on the box body to magnetically absorb waste residue in the reduction box, and to discharge waste oil when the gear oil in the reduction box is replaced.

As a preferred solution, an observation window is installed on the box body at a position corresponding to the driven gear to facilitate observation of the gear oil level in the reduction box body when refueling.

As a preferred solution, a screw plug is installed on the upper end surface of the box cover to add new oil when replacing the gear oil in the reduction box.

As a preferred solution, a breather is installed on the upper end surface of the box cover to release high-temperature gas generated when the power head reduction gearbox is working.

On the other hand, the present invention also provides a vehicle-mounted coal bed methane drilling rig, which is characterized in that it includes the above-mentioned power head reduction gearbox.

Beneficial effects: The vehicle-mounted coal bed methane drilling rig power head reduction gearbox provided by the present invention has a self-sealing and modular sealing device. While achieving effective sealing, seals can be replaced conveniently and quickly, greatly improving operating efficiency. Has the following advantages:

(1) The power head reduction box of the vehicle-mounted coal bed methane drilling rig adopts a self-sealing, modular mud sealing device with a simple structure. It has an installation port for taking and placing the mud sealing device, and has a detachable threaded connection, making it convenient and quick to replace the seal. At the same time, the compression amount of the seal can be adjusted to extend the sealing life.

(2) The power head reduction box of the vehicle-mounted coal bed methane drilling rig uses three sets of bearings to respectively transmit the torque, lifting force and downforce during operation. The structure is simple and practical.

(3) The power head reduction box of the vehicle-mounted coal bed methane drill rig adopts an upper sealing structure and a lower sealing structure to seal the gear oil in the power head reduction box. A spacer is used to convert the relative rotational motion between the skeleton oil seal and the main shaft into a spacer and a The relative rotational movement of the skeleton oil seal effectively extends the service life of the spindle and reduces the cost of replacing the spindle.

Description of the drawings

Figure 1 is a cross-sectional view of the power head reduction gearbox of the vehicle-mounted coal bed methane drilling rig according to the embodiment;

Figure 2 is a front view of the power head reduction gearbox of the vehicle-mounted coal bed methane drilling rig according to the embodiment;

Figure 3 is a top view of the power head reduction gearbox of the vehicle-mounted coal bed methane drilling rig according to the embodiment;

Figure 4 is a partial cross-sectional view of the mud sealing device of the embodiment;

Figure 5 is a partial cross-sectional view of the upper sealing structure of the embodiment;

Figure 6 is a partial cross-sectional view of the lower sealing structure of the embodiment;

In the picture: box body 1, box cover 2, main shaft 3, upper sealing structure 4, hydraulic motor 5, mud sealing device 6, support tube 7, mud umbrella 8, first bearing 9, pressure plate 10, driving gear 11, slave Moving gear 12, second bearing 13, third bearing 14, lower sealing structure 15, observation window 16, installation port 17, screw plug 18, breather 19, magnetic screw plug 20;

Bearing cover 4-1, first skeleton oil seal 4-2, first spacer 4-3, fourth O-ring 4-4, slurry leakage port 4-5, third O-ring 4-6;

Upper packing box gland 6-1, first O-ring 6-2, upper seal gland 6-3, packing 6-4, retaining ring 6-5, wear-resistant tube 6-6, upper packing Box 6-7; lower packing box 6-8, spacer ring 6-9, lower sealing gland 6-10, lower packing box gland 6-11, second O-ring 6-12, screw 6- 13. Oil cup 6-14;

Lower end cover 15-1, fifth O-ring 15-2, second skeleton oil seal 15-3, second spacer 15-4, sixth O-ring 15-5, felt ring 15-6.

Detailed ways

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some of the embodiments of the present invention, rather than all the embodiments. The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the invention, its application or uses. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts fall within the scope of protection of the present invention.

The relative arrangement of components and steps, numerical expressions, and numerical values set forth in these examples do not limit the scope of the invention unless specifically stated otherwise. At the same time, it should be understood that, for convenience of description, the dimensions of various parts shown in the drawings are not drawn according to actual proportional relationships. Techniques, methods and devices known to those of ordinary skill in the relevant art may not be discussed in detail, but where appropriate, such techniques, methods and devices should be considered a part of the specification. In all examples shown and discussed herein, any specific values are to be construed as illustrative only and not as limiting. Accordingly, other examples of the exemplary embodiments may have different values. It should be noted that similar reference numerals and letters refer to similar items in the following figures, so that once an item is defined in one figure, it does not need further discussion in subsequent figures.

As shown in Figure 1, a vehicle-mounted coal bed methane drilling rig power head reduction gearbox of the present invention mainly includes a box body 1, a box cover 2, a main shaft 3, an upper sealing structure 4, a hydraulic motor 5, a mud sealing device 6, and a support tube 7 , lower sealing structure 15. The upper sealing structure 4 and the lower sealing structure 15 are coaxial with the main shaft 3 and are respectively installed at its upper and lower end positions for sealing the gear oil in the box 1 . The mud sealing device 6 is coaxial with the main shaft 3 and is installed on the upper end surface of the main shaft 3 for sealing the high-pressure mud in the hollow main shaft 3 .

In some embodiments, as shown in Figure 1, the upper plane of the box 1 is connected with a box cover 2 using bolts, and the main shaft 3 for outputting power from the reduction box is rotatably installed in the box 1. The box cover 2 is fastened with bolts to a hydraulic motor 5 installed parallel to the main shaft 3 .

As shown in Figure 1, a speed change transmission mechanism is provided between the main shaft 3 and the hydraulic motor 5. The speed change transmission mechanism includes a driving gear 11 coaxially connected to the output shaft of the hydraulic motor 5 and a driving gear 11 coaxially connected to the output shaft of the hydraulic motor 5 and the main shaft. 3. The driven gear 12 is coaxially connected.

The number of the hydraulic motors 5 is M, and M is an even number. In this embodiment, M=4.

The hydraulic motor 5 is a double-displacement cycloid motor, which can achieve high and low speed changes. In the low gear, it outputs low speed and large torque to meet the needs of drilling stuck or drilling hard rock, and in the high gear, it outputs high speed and small torque to meet the needs of normal operations. .

Under the drilling operation conditions of the vehicle-mounted coal bed methane drilling rig, the transmission path of the torque of the power head reduction box is that after the drilling rig power is provided to the hydraulic motor 5, it is transmitted to the driven gear 12 through the driving gear 11, and then to the driven gear 12. The main shaft 3 that is coaxially fixed with the driven gear 12 finally outputs power to the drilling tool connected with the main shaft 3 .

As shown in Figures 1 and 2, the box cover 2 is bolted to a support tube 7 coaxial with the spindle 3. The support tube 7 is a cylindrical structure with a hole for taking in and out of mud. Installation opening 17 of sealing device 6.

The mud sealing device 6 has a self-sealing, modular structure, and its upper and lower ends are trapezoidal threads, which can be threadedly connected to the upper end of the main shaft 3 and the upper end of the support tube 7 respectively. When it is necessary to replace the internal seal of the mud sealing device 6, the mud sealing device 6 can be taken out from the installation port 17 on the support tube 7 by simply loosening the thread.

In some embodiments, as shown in Figure 4, the mud sealing device 6 includes a static sealing structure and a dynamic sealing structure. Among them, the static sealing structure includes the upper packing box gland 6-1, the first O-ring 6-2, the upper sealing gland 6-3, packing 6-4, retaining ring 6-5, and wear-resistant tube 6 -6. Upper packing box 6-7. The dynamic sealing structure includes packing 6-4, lower packing box 6-8, spacer ring 6-9, lower sealing gland 6-10, lower packing box gland 6-11, second O-ring 6- 12. Screws 6-13, oil cups 6-14.

More specifically, the static seal structure is characterized by: the upper packing box gland 6-1 is connected with a trapezoidal thread and installed inside the upper end of the support tube 7, and the packing 6-4 and the upper sealing gland 6-3 are installed in sequence. In the upper packing box 6-7, the wear-resistant pipe 6-6 and the upper sealing sleeve 6-3 are circumferentially connected by rectangular splines, and the retaining ring 6-5 is installed in the annular groove of the wear-resistant pipe 6-6. Prevent the wear-resistant pipe 6-6 from falling from the static sealing structure. The first O-ring 6-2 is installed in the annular groove of the upper end face of the upper sealing sleeve 6-3, and forms an end face static seal with the end face of the support cylinder 7.

More specifically, the characteristics of the dynamic sealing structure are: the lower packing box gland 6-11 is connected with a trapezoidal thread and installed on the upper end of the main shaft 3, and the packing 6-4 and the lower sealing gland 6-10 are installed on the lower packing in sequence. In the box 6-8, the oil cup 6-14 is installed on the lower packing box 6-8 for regular lubrication of the dynamic sealing structure. The screw 6-13 is installed on the lower packing box 6-8 and clicked into the lower sealing pressure. The annular groove of the sleeve 6-10 prevents the packing 6-4, the spacer ring 6-9 and the lower sealing sleeve 6-10 from falling out of the lower packing box 6-8 during the assembly process. The second O-shaped sealing ring 6-12 is installed in the end face annular groove of the lower sealing sleeve 6-10, and forms an end face static seal with the end face of the main shaft 3.

In the above-mentioned static sealing structure and dynamic sealing structure, the number of packings 6-4 can be adjusted according to needs, and can be one or more. Spacers 6-9 are provided between the plurality of packings 6-4 for sealing. Adjacent packings are spaced 6-4 apart.

In the dynamic sealing structure, the number of screws 6-13 is N. In this embodiment, N=2.

During the drilling operation of the vehicle-mounted coal bed methane drilling rig, the spindle 3 drives the dynamic sealing structure to rotate around the wear-resistant tube 6-6 of the static sealing structure, thereby sealing the high-pressure mud in the rotating/non-rotating position.

After the truck-mounted coal bed methane drilling rig has been working for a period of time, the packing 6-4 has certain wear and tear, resulting in a decrease in sealing performance. At this time, the upper packing box gland 6-1 and the lower packing box gland 6-11 can be tightened in sequence. , adjust the compression amount of packing 6-4 to improve the service life of the seal.

In some embodiments, as shown in Figure 1, the main shaft 3 is equipped with a pressure plate 10 that compresses the driven gear 12. The pressure plate 10 is threadedly connected to the outer wall of the main shaft 3. In the axial direction of the main shaft 3 , the pressure plate 10 and the driven gear 12 are fixed with bolts to prevent the driven gear 12 from moving axially.

In some embodiments, as shown in Figure 1, the first bearing 9 is fixedly installed between the main shaft 3 and the box cover 2. The box cover 2 is provided with a first bearing seat. The first bearing 9 is The inner ring is fixedly connected to the main shaft 3, and the outer ring of the first bearing 9 is clamped and fixed on the first bearing seat inside the box cover 2; to maximize the bearing spacing, and to bear the torsion during operation through the box cover 2 , righting the spindle 3, improving rotational stability and prolonging the life of the seal. The second bearing 13 is fixedly installed in the upper middle part between the main shaft 3 and the box body 1, and is close to the bottom of the driven gear 12. A second bearing seat is provided in the upper middle part of the box body 1. The inner ring of the bearing 13 is fixedly connected to the spindle 3, and the outer ring of the second bearing 13 is clamped and fixed on the second bearing seat inside the box 1 so as to bear the drilling tools installed on the spindle 3 through the box 1. downward pulling force to withstand the vertical downward force. The third bearing 14 is fixedly installed in the lower part between the main shaft 3 and the box 1. A third bearing seat is provided in the lower part of the box 1. The inner ring of the third bearing 14 is fixedly connected to the main shaft 3. , the outer ring of the third bearing 14 is fixed to the third bearing seat inside the box 1; the box 1 is used to bear the upward pressure of the drilling tool installed on the spindle 3 to withstand the vertical upward force. .

Under the lifting operation conditions of the vehicle-mounted coal bed methane drilling rig, the transmission path of the lifting force is that the main shaft 3 bears the downward pulling force from the drilling tool, and is transmitted to the driven force through the pressure plate 10 threadedly connected with the main shaft 3 The gear 12 and the second bearing 13 are ultimately borne by the box 1 .

Under the pressing operation condition of the vehicle-mounted coal bed methane drilling rig, the transmission path of the downward pressure is that the main shaft 3 bears the upward pressure from the drilling tool, and is transmitted to the box through the end surface of the main shaft 3 in contact with the third bearing 14 Body 1.

As shown in Figures 1 and 5, the upper end of the first bearing 9 is provided with an upper sealing structure 4, including a bearing cover 4-1, a first skeleton oil seal 4-2, a first spacer 4-3, a fourth O Type sealing ring 4-4, slurry leakage port 4-5, third O-ring sealing ring 4-6. The bearing cover 4-1 and the box cover 2 are connected with bolts to compress the first bearing 9. The bearing cover 4-1 is equipped with two sets of first skeleton oil seals 4-2 installed back to back. On the one hand, it prevents external mud or dust from entering the reduction box and contaminating the gear oil. On the other hand, it prevents the internal gear oil from seeping out. The third O-ring 4-6 is used to seal the bearing cover 4-1 and the box cover 2 to prevent the gear oil in the reduction box from seeping out between them.

After the upper sealing structure 4 works for a period of time, at the joint surface of the first skeleton oil seal 4-2 and the main shaft 3, the first skeleton oil seal 4-2 will cause certain wear to the rotating main shaft 3, causing Risk of slurry intrusion or oil leakage. In this embodiment, a first spacer 4-3 is provided between the first skeleton oil seal 4-2 and the main shaft 3, thereby converting the relative rotation seal between the main shaft 3 and the first skeleton oil seal 4-2 into a first The relative rotation seal between the spacer 4-3 and the first skeleton oil seal 4-2. After the first skeleton oil seal 4-2 wears the first spacer 4-3, you only need to replace the first spacer 4-3. Thereby extending the service life of the spindle 3 and reducing production costs. The first spacer 4-3 is tightly connected to the main shaft 3, and a fourth O-ring 4-4 is provided between the first spacer 4-3 and the main shaft 3 to prevent gear oil from entering the reduction box. Seeps out from between the two.

As shown in Figures 1 and 5, above the bearing cover 4-1, a mud umbrella 8 is installed on the main shaft 3, and a mud leakage port 4-5 is provided on the support tube 7. When mud leakage occurs, the mud can flow out from the mud leakage port 4-5, thereby extending the life of the first skeleton oil seal 4-2 and preventing mud and other debris from connecting between the bearing cover 4-1 and the first partition. Set 4-3 into the reduction box.

As shown in Figures 1 and 6, the lower end of the box 1 is provided with the lower sealing structure 15, including a lower end cover 15-1, a fifth O-ring 15-2, a second skeleton oil seal 15-3, a The second spacer 15-4, the sixth O-ring 15-5, and the felt ring 15-6. The lower end cover 15-1 is connected to the box body 1 with bolts. The lower end cover 15-1 is equipped with two sets of second skeleton oil seals 15-3 installed in the same direction to seal the gear oil in the reduction box. A fifth O-ring 15-2 is used to seal the lower end cover 15-1 and the box 1 to prevent the gear oil in the reduction box from seeping out between them. The lower end cover 15-1 is provided with a felt ring 15-6 to prevent external mud or dust from entering the reduction box body and contaminating the gear oil.

In order to extend the service life of the main shaft 3 and reduce the cost of replacing the main shaft 3, a second spacer 15-4 is provided between the second skeleton oil seal 15-3 and the main shaft 3, so that the main shaft is The relative rotating seal between 3 and the second skeleton oil seal 15-3 is converted into the relative rotating seal between the second spacer sleeve 15-4 and the second skeleton oil seal 15-3. After the second skeleton oil seal 15-3 separates the second spacer sleeve 15 After -4 is worn, only the second spacer 15-4 needs to be replaced. The second spacer 15-4 is tightly connected to the main shaft 3. A sixth O-ring 15-5 is provided between the second spacer 15-4 and the main shaft 3 to prevent the gear oil in the reduction box from seeping out between them.

As shown in Figure 2, a magnetic screw plug 20 is installed on the box 1 to magnetically absorb the waste residue in the reduction box and discharge the waste oil when replacing the gear oil in the reduction box; at the same time, a magnetic screw plug 20 is installed on the box 1 with the slave. An observation window 16 is installed at the corresponding position of the moving gear 12 to facilitate observation of the gear oil level in the reduction box when refueling for the first time.

As shown in Figure 3, a screw plug 18 is installed on the upper end surface of the box cover 2 to add new oil when replacing the gear oil in the reduction box. At the same time, a breather 19 is installed to release the gas generated when the power head reduction box is working. of high-temperature gas.

The vehicle-mounted coal bed methane drilling rig power head reduction gearbox provided by the invention has a simple structure and has a self-sealing and modular sealing device. While achieving effective sealing, seals can be replaced conveniently and quickly, greatly improving operating efficiency. Has the following advantages:

(1) The power head reduction gearbox of the vehicle-mounted coal bed methane drilling rig adopts a self-sealing and modular mud sealing device. It has a simple structure and is convenient and quick to replace the seal. At the same time, the compression amount of the seal can be adjusted to extend the sealing life.

(2) The power head reduction box of the vehicle-mounted coal bed methane drill rig adopts an upper sealing structure and a lower sealing structure to seal the gear oil in the power head reduction box. A spacer is used to convert the relative rotational motion between the skeleton oil seal and the main shaft into a spacer and a The relative rotational movement of the skeleton oil seal effectively extends the service life of the spindle and reduces the cost of replacing the spindle.

(3) The power head reduction box of the vehicle-mounted coal bed methane drilling rig uses three sets of bearings to transmit the torque, lifting force and downforce during operation. The structure is simple and practical.

In the description of this application, it needs to be understood that the terms "center", "longitudinal", "lateral", "front", "rear", "left", "right", "vertical", "horizontal", The orientations or positional relationships indicated by "top", "bottom", "inner", "outside", etc. are based on the orientations or positional relationships shown in the drawings. They are only for convenience of describing the present invention and simplifying the description, rather than indicating or implying. It means that the device or element referred to must have a specific orientation, be constructed and operate for a specific orientation, and therefore should not be construed as a limitation on the scope of protection of the present invention.

The above are only the preferred embodiments of the present invention. It should be pointed out that those of ordinary skill in the art can make several improvements and modifications without departing from the principles of the present invention. These improvements and modifications can also be made. should be regarded as the protection scope of the present invention.

Claims (16)

1. The utility model provides a unit head reducing gear box which characterized in that: comprises a box body, a box cover, a main shaft, a driven gear and a detachable and replaceable slurry sealing device;

the box body is rotationally provided with a main shaft for outputting power of the reduction box, and the driven gear is coaxially and fixedly connected with the main shaft to transmit rotary power to the main shaft; the slurry sealing device is coaxial with the main shaft and is arranged on the upper end surface of the main shaft and used for sealing high-pressure slurry in the hollow main shaft;

the slurry sealing device comprises a wear-resistant pipe, a static sealing structure and a dynamic sealing structure; the abrasion-resistant pipe is fixedly connected with the static sealing structure, the dynamic sealing structure is fixedly connected to the upper end of the main shaft, the dynamic sealing structure is rotationally connected with the abrasion-resistant pipe, and in the drilling operation process, the main shaft drives the dynamic sealing structure to rotate around the abrasion-resistant pipe of the static sealing structure, so that high-pressure slurry at a rotating/non-rotating position is sealed;

the box cover is detachably and fixedly connected with the upper end face of the box body; a supporting cylinder coaxial with the main shaft is fixedly connected to the box cover; the novel spindle motor is characterized by further comprising a first bearing, wherein the first bearing is fixedly arranged between the spindle and the box cover, a first bearing seat is arranged on the box cover, an inner ring of the first bearing is fixedly connected with the spindle, and an outer ring of the first bearing is clamped and fixed on the first bearing seat on the inner side of the box cover; the torque force is born by the box cover during working so as to straighten the main shaft and improve the rotation stability; the second bearing is fixedly arranged at the middle upper part between the main shaft and the box body, the driven gear is close to the upper part of the second bearing, a second bearing seat is arranged at the middle upper part in the box body, the inner ring of the second bearing is fixedly connected with the main shaft, and the outer ring of the second bearing is fixedly clamped at the second bearing seat at the inner side of the box body; to bear the downward pulling force of the drilling tool installed on the spindle through the box body; the device comprises a main shaft, a box body, a first bearing, a second bearing, a third bearing, a first bearing and a second bearing, wherein the first bearing is fixedly arranged at the lower part between the main shaft and the box body; to bear upward pressure of a drilling tool mounted on the spindle through a case;

the upper end and the lower end of the slurry sealing device are of a threaded structure and are respectively in threaded connection with the upper end of the main shaft and the upper end of the supporting cylinder; the static sealing structure comprises an upper packing box gland, a first O-shaped sealing ring, an upper sealing pressing sleeve, packing, a check ring and an upper packing box; the upper packing box pressing cover is in threaded connection with the inner side of the upper end of the supporting cylinder, the packing and the upper sealing pressing sleeve are sequentially arranged in the upper packing box, the wear-resisting pipe and the upper sealing pressing sleeve are fixedly connected in the circumferential direction by adopting rectangular splines, the retainer ring is arranged in an annular clamping groove of the wear-resisting pipe, and the wear-resisting pipe is prevented from falling from the static sealing structure; the first O-shaped sealing ring is arranged in an annular groove on the upper end surface of the upper sealing pressing sleeve and forms end surface static seal with the end surface of the supporting cylinder; the dynamic sealing structure comprises a packing, a lower packing box, a lower sealing pressing sleeve, a lower packing box pressing cover, a second O-shaped sealing ring, a screw and an oil cup; the gland of the lower packing box is connected with the upper end of the main shaft through threads, the packing and the lower sealing pressing sleeve are sequentially arranged in the lower packing box, an oil cup is arranged on the lower packing box and used for periodically lubricating a dynamic sealing structure, a screw circumference is arranged on the lower packing box and is clamped into an annular groove of the lower sealing pressing sleeve, and packing and the lower sealing pressing sleeve are prevented from falling out of the lower packing box in the assembly process; the second O-shaped sealing ring is arranged in an end surface ring groove of the lower sealing pressing sleeve and forms end surface static seal with the end surface of the main shaft;

an upper sealing structure is arranged at the upper end of the first bearing and comprises a bearing cover plate, a first framework oil seal, a first spacer bush and a third O-shaped sealing ring; the bearing cover plate is fixedly connected with the box cover through bolts so as to compress the first bearing; two groups of first framework oil seals which are arranged back to back are arranged on the bearing cover plate, so that on one hand, external slurry or dust is prevented from entering the reduction gearbox to pollute gear oil, and on the other hand, the internal gear oil is prevented from exuding; the bearing cover plate and the box cover are sealed by a third O-shaped sealing ring so as to prevent the gear oil in the reduction box from seeping out from the space between the bearing cover plate and the box cover; a first spacer bush is arranged between the first framework oil seal and the main shaft, so that the relative rotary seal between the main shaft and the first framework oil seal is converted into the relative rotary seal between the first spacer bush and the first framework oil seal; the first spacer bush is tightly matched and fixedly connected with the main shaft;

the lower end of the box body is provided with a lower sealing structure, and the lower sealing structure comprises a lower end cover, a fifth O-shaped sealing ring, a second framework oil seal and a felt ring; the lower end cover is fixedly connected with the box body by bolts, and two groups of second framework oil seals which are installed in the same direction are arranged on the lower end cover and are used for sealing gear oil in the reduction box body; the lower end cover and the box body are sealed by a fifth O-shaped sealing ring so as to prevent the gear oil in the reduction box body from seeping out from the lower end cover and the box body; the lower end cover is provided with a felt ring for preventing external mud or dust from entering the reduction gearbox to pollute gear oil; a second spacer bush is arranged between the second framework oil seal and the main shaft, so that the relative rotary seal between the main shaft and the second framework oil seal is converted into the relative rotary seal between the second spacer bush and the second framework oil seal; the second spacer bush is tightly matched and fixedly connected with the main shaft.

2. The powerhead reduction gearbox of claim 1, wherein: the supporting cylinder is of a cylindrical structure, and an installation opening for taking and placing the slurry sealing device is formed in the supporting cylinder.

3. The powerhead reduction gearbox of claim 1, wherein: in the static sealing structure and the dynamic sealing structure, the number of packing is one or more, and a spacing ring is arranged among the packing.

4. The powerhead reduction gearbox of claim 1, wherein: the hydraulic motor provides power for the rotation of the main shaft, a variable speed transmission mechanism is arranged between the main shaft and the hydraulic motor, the variable speed transmission mechanism comprises a driving gear coaxially and fixedly connected with an output shaft of the hydraulic motor and a driven gear coaxially and fixedly connected with the main shaft, the driving gear is meshed with the driven gear, and the driving gear and the driven gear are located in a box body.

5. The powerhead reduction gearbox of claim 4, wherein: the main shaft cover is equipped with and is used for compressing tightly the pressure disk of driven gear, the pressure disk with main shaft outer wall threaded connection in main shaft axis direction, the pressure disk with driven gear adopts the bolt rigid coupling, is used for preventing driven gear axial float.

6. The power head reduction gearbox according to claim 4 or 5, wherein: the hydraulic motor is connected and installed on the box cover, and the hydraulic motor is installed in parallel with the main shaft.

7. The powerhead reduction gearbox of claim 1, wherein: the gear oil sealing device is characterized by further comprising an upper sealing structure and a lower sealing structure, wherein the upper sealing structure and the lower sealing structure are coaxial with the main shaft and are respectively arranged at the upper end position and the lower end position of the box body and used for sealing gear oil in the box body.

8. The powerhead reduction gearbox of claim 1, wherein: the upper sealing structure further comprises a fourth O-shaped sealing ring, and the fourth O-shaped sealing ring is arranged between the first spacer bush and the main shaft so as to prevent gear oil in the reduction gearbox from seeping out from between the first spacer bush and the main shaft.

9. The powerhead reduction gearbox of claim 1, wherein: and a mud umbrella is arranged on the main shaft at the position above the bearing cover plate.

10. The powerhead reduction gearbox of claim 1, wherein: and a slurry leakage port is arranged on the supporting cylinder and used for enabling slurry to flow out from the slurry leakage port when slurry leakage occurs, so that the service life of the first framework oil seal is prolonged, and the slurry is prevented from entering the reduction gearbox from the position between the bearing cover plate and the first spacer bush.

11. The powerhead reduction gearbox of claim 1, wherein: a sixth O-shaped sealing ring is arranged between the second spacer bush and the main shaft to prevent the gear oil in the reduction gearbox from seeping out from between the second spacer bush and the main shaft.

12. The powerhead reduction gearbox of claim 1, wherein: the box body is provided with a magnetic screw plug for magnetically sucking waste residues in the reduction box body and discharging waste oil when gear oil in the reduction box body is replaced.

13. The powerhead reduction gearbox of claim 1, wherein: an observation window is arranged at a position on the box body corresponding to the driven gear so as to observe the gear oil level in the reduction box body during oiling.

14. The powerhead reduction gearbox of claim 1, wherein: and a screw plug is arranged on the upper end surface of the box cover to replace gear oil in the reduction box body, and new oil is added.

15. The powerhead reduction gearbox of claim 1, wherein: and the upper end surface of the box cover is provided with a ventilator for releasing high-temperature gas generated during the operation of the power head reduction gearbox.

16. A vehicle-mounted coalbed methane drilling machine, characterized by comprising the power head reduction gearbox of any one of claims 1-15.