Wear-resistant torque-reducing tool for well drilling and preparation method of wear-resistant torque-reducing tool

Abstract

The invention discloses a wear-resistant torque-reducing tool for well drilling and a preparation method thereof, and belongs to the technical field of torque-reducing connectors, the wear-resistant torque-reducing tool comprises a torque-reducing connector body, an internal composite material lubricating sleeve, an alloy steel reinforced inner framework, a composite material friction-reducing torque-reducing outer sleeve and an end composite material lubricating sleeve; the inner composite material lubricating sleeve, the composite material friction-reducing and torque-reducing outer sleeve and the end composite material lubricating sleeve are prepared from a wear-resistant composite material; the wear-resistant composite material is prepared by taking polytetrafluoroethylene resin as a base material and compounding graphite, glass fibers and modified molybdenum disulfide. According to the invention, polytetrafluoroethylene resin is taken as a base material, graphite, glass fiber and modified molybdenum disulfide are compounded to prepare the wear-resistant composite material, and the friction coefficient of the wear-resistant composite material with metal is reduced from 0.4 to about 0.2. The loss of torque transmission is reduced, the safety coefficient is improved, and safe, high-quality and rapid drilling operation is achieved.

Description

Technical Field

[0001] The invention relates to the technical field of torsion reducing joints, and in particular to a wear-resistant torsion reducing tool for drilling and a preparation method thereof. Background Art

[0002] In oil and gas drilling operations, the rotary power of the drill bit is transmitted to the drill bit through the drill string by the turntable on the drilling platform or the top drive device on the top. When drilling directional wells, the transmission of this torsional power becomes very difficult due to the mutual friction between the drill string and the well wall or the drill string and the casing. Especially in horizontal well and extended reach well drilling operations, the loss of torque affects the efficiency of the drilling rig and reduces the maximum drilling capacity of the drilling rig. On the other hand, due to the mutual friction between the drill string and the well wall, the drill string and the casing, the service life of the drill string and the casing will be reduced, and the well wall will become irregular. In addition, due to the loss of torque transmission, in order to ensure the drilling torque of the drill bit, the torsional load of the drill string must be increased, which will reduce the safety factor of the drill string. These factors will affect safe, high-quality and fast drilling operations.

[0003] Based on this, the present invention designs a wear-resistant torque-reducing tool for drilling and a preparation method thereof to solve the above-mentioned problems. Summary of the invention

[0004] In view of the above-mentioned shortcomings of the prior art, the present invention provides a wear-resistant torque-reducing tool for drilling and a preparation method thereof.

[0005] To achieve the above objectives, the present invention is implemented through the following technical solutions: A wear-resistant torque-reducing tool for drilling, comprising a torque-reducing joint body, an internal composite material lubricating sleeve, an alloy steel reinforced inner skeleton, a composite material friction-reducing torque-reducing outer sleeve and an end composite material lubricating sleeve; The outer side of the torsion reducing joint body is provided with a plurality of annular grooves for fitting the internal composite material lubricating sleeve, the outer side of the internal composite material lubricating sleeve is rotatably connected to an alloy steel reinforced inner frame, the outer side of the alloy steel reinforced inner frame is rotatably connected to a composite material friction and torsion reducing outer sleeve, and both ends of the torsion reducing joint body are fixedly connected to end composite material lubricating sleeves; The internal composite material lubricating sleeve, the composite material anti-friction and anti-torque outer sleeve and the end composite material lubricating sleeve are made of wear-resistant composite material; The wear-resistant composite material is prepared by using 45-58 parts of polytetrafluoroethylene resin as a base material and compounding 3-6 parts of graphite, 1-4 parts of glass fiber and 4-8 parts of modified molybdenum disulfide; The preparation method of the wear-resistant composite material comprises the following steps: Step 1: preparing modified molybdenum disulfide; The fly ash, molybdenum disulfide powder and graphite powder are uniformly mixed in a ratio of 3-8:15-23:4-9 to obtain a mixed powder; Preheating the mixed powder to 50-70° C., spreading and compacting the mixed powder, sending the mixed powder into a steam generating chamber, and grinding the mixed powder with isopropyl stearate at 375-380° C. to obtain modified molybdenum disulfide; Step 2: Weigh 45-58 parts of polytetrafluoroethylene resin and evenly disperse them in anhydrous ethanol, and evenly divide them into four equal parts, record them as resin solutions A, B, C and D, and add modified molybdenum disulfide, graphite and glass fiber to the resin solutions A, B and C respectively and mix them evenly; Step 3: Add resin solution A to resin solution D to obtain resin solution E, stir for 10-15 minutes, heat up and stand for 20-25 minutes; at the same time, add resin solution B and resin solution C to resin solution D, heat up and stir to obtain a masterbatch; Step 4: Filter, dry and crush the masterbatch to obtain masterbatch, and press and sinter the masterbatch to obtain the wear-resistant composite material.

[0006] A method for preparing the wear-resistant torque-reducing tool for drilling comprises the following steps: Step 1: preparing modified molybdenum disulfide; The fly ash, molybdenum disulfide powder and graphite powder are uniformly mixed in a ratio of 3-8:15-23:4-9 to obtain a mixed powder; Preheating the mixed powder to 50-70° C., spreading and compacting the mixed powder, sending the mixed powder into a steam generating chamber, and grinding the mixed powder with isopropyl stearate at 375-380° C. to obtain modified molybdenum disulfide; Step 2: Weigh 45-58 parts of polytetrafluoroethylene resin and evenly disperse them in anhydrous ethanol, and evenly divide them into four equal parts, record them as resin solutions A, B, C and D, and add modified molybdenum disulfide, graphite and glass fiber to the resin solutions A, B and C respectively and mix them evenly; Step 3: Add resin solution A to resin solution D to obtain resin solution E, stir for 10-15 minutes, heat to 50-52°C and stand for 20-25 minutes; at the same time, add resin solution B and resin solution C to resin solution D, heat to 50-52°C and stir for 20-25 minutes to obtain a masterbatch; Step 4: Filtering, drying and crushing the masterbatch to obtain masterbatch, and pressing and sintering the masterbatch to obtain the wear-resistant composite material; Step 5: shaping the wear-resistant composite material to obtain an internal composite material lubricating sleeve, a composite material anti-friction and anti-torque outer sleeve, and an end composite material lubricating sleeve; Step six: Compound the internal composite material lubricating sleeve, the composite material anti-friction and anti-torsion outer sleeve and the end composite material lubricating sleeve with the alloy steel reinforced inner skeleton and the anti-torsion joint body to obtain a wear-resistant anti-torsion tool for drilling.

[0007] Furthermore, in step 1, fly ash with a particle size of 70-90 μm, molybdenum disulfide powder with a particle size of 5-10 μm and graphite powder with a particle size of 20-30 μm are uniformly mixed in a ratio of 3-8:15-23:4-9 to obtain a mixed powder.

[0008] Furthermore, in step 1, the mixed powder is preheated to 50-70°C, the mixed powder is spread to a thickness of 1.2-1.5 cm and compacted, the mixed powder is sent into a steam generating chamber, and the mixed powder is ground by isopropyl stearate at 375-380°C to obtain modified molybdenum disulfide.

[0009] Furthermore, step three is specifically as follows: adding resin solution A preheated to 40-45°C to resin solution D preheated to 40-45°C to obtain resin solution E, stirring for 10-15 minutes, heating to 50-52°C and standing for 20-25 minutes; at the same time, adding resin solution B and resin solution C preheated to 40-45°C to resin solution D, heating to 50-52°C and stirring for 20-25 minutes to obtain a masterbatch.

[0010] Furthermore, in step three, the stirring speed is 150-200 r / min.

[0011] Furthermore, the alloy steel reinforced inner skeleton has the following mass percentage composition: carbon 0.01-0.15%, silicon ≤3%, manganese ≤3%, aluminum ≤0.08%, and the remainder is Fe and impurities.

[0012] Furthermore, the torsion reducing joint body is made of polytetrafluoroethylene.

[0013] Compared with the prior art, the present invention has the following beneficial effects: the present invention uses polytetrafluoroethylene resin as a base material, and compound graphite, glass fiber and modified molybdenum disulfide to prepare a wear-resistant composite material, and reduces the friction coefficient between the polytetrafluoroethylene resin and the metal from 0.4 to about 0.2; During directional well drilling, the external drive device drives the torque reducing joint body to rotate, and the torque reducing joint body drives the internal composite material lubricating sleeve to rotate. While the internal composite material lubricating sleeve rotates, it generates friction with the alloy steel reinforced inner frame. Since the mutual friction between the composite material friction reducing and torque reducing outer sleeve and the internal composite material lubricating sleeve and the alloy steel reinforced inner frame is small, the transmission of this torsional power becomes very smooth. Especially in horizontal well and large displacement well drilling operations, it not only improves the efficiency of the drilling rig, but also improves the maximum drilling capacity of the drilling rig; on the other hand, since the mutual friction between the composite material friction reducing and torque reducing outer sleeve and the internal composite material lubricating sleeve and the alloy steel reinforced inner frame is small, the service life of the composite material friction reducing and torque reducing outer sleeve, the internal composite material lubricating sleeve and the alloy steel reinforced inner frame is improved. Moreover, since the loss of torque transmission is reduced, there is no need to increase the torsional load, which will improve the safety factor of the torque reducing joint body and realize safe, high-quality and fast drilling operations. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] 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 prior art descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention, and for ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0015] Figure 1 It is a structural schematic diagram of a wear-resistant torque-reducing tool for drilling of the present invention; Figure 2 for Figure 1 Enlarged view of point A in the middle.

[0016] The numbers in the figure represent: 1. Torque reducing joint body; 2. Internal composite material lubricating sleeve; 3. Alloy steel reinforced inner skeleton; 4. Composite material friction reducing and torque reducing outer sleeve; 5. Composite material lubricating sleeve at the end. DETAILED DESCRIPTION

[0017] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0018] Embodiment 1: In some embodiments, please refer to the attached Figure 1-2, a wear-resistant torque reducing tool for drilling, comprising a torque reducing joint body 1, an internal composite material lubricating sleeve 2, an alloy steel reinforced inner skeleton 3, a composite material friction reducing and torque reducing outer sleeve 4 and an end composite material lubricating sleeve 5; The outer side of the torque reducing joint body 1 is provided with a plurality of annular grooves for fitting the internal composite material lubricating sleeve 2, that is, the internal composite material lubricating sleeve 2 is fixedly connected to the outer side of the torque reducing joint body 1, the outer side of the internal composite material lubricating sleeve 2 is rotatably connected to an alloy steel reinforced inner frame 3, the outer side of the alloy steel reinforced inner frame 3 is rotatably connected to a composite material friction reducing and torque reducing outer sleeve 4, and both ends of the torque reducing joint body 1 are fixedly connected to end composite material lubricating sleeves 5; The alloy steel reinforced inner skeleton 3 has the following mass percentage composition: carbon 0.01-0.15%, silicon ≤3%, manganese ≤3%, aluminum ≤0.08%, and the balance is Fe and impurities; The torsion reducing joint body 1 is made of polytetrafluoroethylene; The internal composite material lubricating sleeve 2, the composite material anti-friction and anti-torque outer sleeve 4 and the end composite material lubricating sleeve 5 are made of wear-resistant composite materials; The wear-resistant composite material is prepared by using 58g of polytetrafluoroethylene resin as a base material and compounding 6g of graphite, 4g of glass fiber and 8g of modified molybdenum disulfide; The preparation method of the wear-resistant composite material comprises the following steps: Step 1: preparing modified molybdenum disulfide; Fly ash with a particle size of 90 μm, molybdenum disulfide powder with a particle size of 10 μm, and graphite powder with a particle size of 30 μm are uniformly mixed in a ratio of 8:23:9 to obtain a mixed powder; The mixed powder was preheated to 70° C., the mixed powder was spread to a thickness of 1.5 cm and compacted, the mixed powder was sent into a steam generating chamber, and the mixed powder was ground by isopropyl stearate at 380° C. to obtain modified molybdenum disulfide; (Principle: isopropyl stearate is used to generate modified gas through a steam generator and released through the gaps on an operating table. The operating table is arranged above the steam generator. A plurality of gaps are formed between the operating table and the first steam chamber. When the mixed powder is placed on the operating table, the modified gas contacts the lower surface of the mixed powder. Reference structure: A graphite modification device and modification method disclosed in Chinese patent CN109095465B) Step 2: Weigh 58 g of polytetrafluoroethylene resin and evenly disperse it in anhydrous ethanol, and evenly divide it into four equal parts, record them as resin solutions A, B, C and D, and add modified molybdenum disulfide, graphite and glass fiber to the resin solutions A, B and C respectively and mix them evenly; Step 3: Add resin solution A preheated to 45°C to resin solution D preheated to 45°C to obtain resin solution E, stir at 200 r / min for 15 minutes, heat to 52°C and stand for 25 minutes; at the same time, add resin solution B and resin solution C preheated to 45°C to resin solution D, heat to 52°C and stir at 200 r / min for 25 minutes to obtain a masterbatch; Step 4: Filtering, drying and crushing the masterbatch to obtain masterbatch, and pressing and sintering the masterbatch to obtain the wear-resistant composite material; Step 5: shaping the wear-resistant composite material to obtain an inner composite material lubricating sleeve 2, a composite material anti-friction and anti-torque outer sleeve 4 and an end composite material lubricating sleeve 5; Step six: Compound the internal composite material lubricating sleeve 2, the composite material anti-friction and torque reducing outer sleeve 4 and the end composite material lubricating sleeve 5 with the alloy steel reinforced inner skeleton 3 and the torque reducing joint body 1 to obtain a wear-resistant torque reducing tool for drilling.

[0019] Embodiment 2: In some embodiments, please refer to the attached Figure 1-2 , a wear-resistant torque reducing tool for drilling, comprising a torque reducing joint body 1, an internal composite material lubricating sleeve 2, an alloy steel reinforced inner skeleton 3, a composite material friction reducing and torque reducing outer sleeve 4 and an end composite material lubricating sleeve 5; The outer side of the torque reducing joint body 1 is provided with a plurality of annular grooves for fitting the internal composite material lubricating sleeve 2, the outer side of the internal composite material lubricating sleeve 2 is rotatably connected to an alloy steel reinforced inner frame 3, the outer side of the alloy steel reinforced inner frame 3 is rotatably connected to a composite material friction reducing and torque reducing outer sleeve 4, and both ends of the torque reducing joint body 1 are fixedly connected to end composite material lubricating sleeves 5; The alloy steel reinforced inner skeleton 3 has the following mass percentage composition: carbon 0.01-0.15%, silicon ≤3%, manganese ≤3%, aluminum ≤0.08%, and the remainder is Fe and impurities; The torsion reducing joint body 1 is made of polytetrafluoroethylene; The internal composite material lubricating sleeve 2, the composite material anti-friction and anti-torque outer sleeve 4 and the end composite material lubricating sleeve 5 are made of wear-resistant composite materials; The wear-resistant composite material is prepared by using 45g of polytetrafluoroethylene resin as a base material and compounding 3g of graphite, 1g of glass fiber and 4g of modified molybdenum disulfide; The preparation method of the wear-resistant composite material comprises the following steps: Step 1: preparing modified molybdenum disulfide; Fly ash with a particle size of 70 μm, molybdenum disulfide powder with a particle size of 5 μm, and graphite powder with a particle size of 20 μm are uniformly mixed in a ratio of 3:15:4 to obtain a mixed powder; The mixed powder was preheated to 50° C., the mixed powder was spread to a thickness of 1.2 cm and compacted, the mixed powder was sent into a steam generating chamber, and the mixed powder was ground by isopropyl stearate at 375° C. to obtain modified molybdenum disulfide; (Principle: isopropyl stearate is used to generate modified gas through a steam generator and released through the gaps on an operating table. The operating table is arranged above the steam generator. A plurality of gaps are formed between the operating table and the first steam chamber. When the mixed powder is placed on the operating table, the modified gas contacts the lower surface of the mixed powder. Reference structure: A graphite modification device and modification method disclosed in Chinese patent CN109095465B) Step 2: Weigh 45g of polytetrafluoroethylene resin and evenly disperse it in anhydrous ethanol, and evenly divide it into four equal parts, record them as resin solutions A, B, C and D, and add modified molybdenum disulfide, graphite and glass fiber to the resin solutions A, B and C respectively and mix them evenly; Step 3: Add resin solution A preheated to 40°C to resin solution D preheated to 40°C to obtain resin solution E, stir at 150 r / min for 10 min, heat to 50°C and stand for 20 min; at the same time, add resin solution B and resin solution C preheated to 40°C to resin solution D, heat to 50°C and stir at 150 r / min for 20 min to obtain a masterbatch; Step 4: Filtering, drying and crushing the masterbatch to obtain masterbatch, and pressing and sintering the masterbatch to obtain the wear-resistant composite material; Step 5: shaping the wear-resistant composite material to obtain an inner composite material lubricating sleeve 2, a composite material anti-friction and anti-torque outer sleeve 4 and an end composite material lubricating sleeve 5; Step six: Compound the internal composite material lubricating sleeve 2, the composite material anti-friction and torque reducing outer sleeve 4 and the end composite material lubricating sleeve 5 with the alloy steel reinforced inner skeleton 3 and the torque reducing joint body 1 to obtain a wear-resistant torque reducing tool for drilling.

[0020] Embodiment 3: In some embodiments, please refer to the attached Figure 1-2 , a wear-resistant torque reducing tool for drilling, comprising a torque reducing joint body 1, an internal composite material lubricating sleeve 2, an alloy steel reinforced inner skeleton 3, a composite material friction reducing and torque reducing outer sleeve 4 and an end composite material lubricating sleeve 5; The outer side of the torque reducing joint body 1 is provided with a plurality of annular grooves for fitting the internal composite material lubricating sleeve 2, the outer side of the internal composite material lubricating sleeve 2 is rotatably connected to an alloy steel reinforced inner frame 3, the outer side of the alloy steel reinforced inner frame 3 is rotatably connected to a composite material friction reducing and torque reducing outer sleeve 4, and both ends of the torque reducing joint body 1 are fixedly connected to end composite material lubricating sleeves 5; The alloy steel reinforced inner skeleton 3 has the following mass percentage composition: carbon 0.01-0.15%, silicon ≤3%, manganese ≤3%, aluminum ≤0.08%, and the remainder is Fe and impurities; The torsion reducing joint body 1 is made of polytetrafluoroethylene; The internal composite material lubricating sleeve 2, the composite material anti-friction and anti-torque outer sleeve 4 and the end composite material lubricating sleeve 5 are made of wear-resistant composite materials; The wear-resistant composite material is prepared by using 50g of polytetrafluoroethylene resin as a base material and compounding 5g of graphite, 3g of glass fiber and 7g of modified molybdenum disulfide; The preparation method of the wear-resistant composite material comprises the following steps: Step 1: preparing modified molybdenum disulfide; Fly ash with a particle size of 80 μm, molybdenum disulfide powder with a particle size of 6 μm, and graphite powder with a particle size of 22 μm are uniformly mixed in a ratio of 4:18:5 to obtain a mixed powder; The mixed powder was preheated to 55° C., the mixed powder was spread to a thickness of 1.3 cm and compacted, the mixed powder was sent into a steam generating chamber, and the mixed powder was ground by isopropyl stearate at 378° C. to obtain modified molybdenum disulfide; (Principle: isopropyl stearate is used to generate modified gas through a steam generator and released through the gaps on an operating table. The operating table is arranged above the steam generator. A plurality of gaps are formed between the operating table and the first steam chamber. When the mixed powder is placed on the operating table, the modified gas contacts the lower surface of the mixed powder. Reference structure: A graphite modification device and modification method disclosed in Chinese patent CN109095465B) Step 2: Weigh 50 g of polytetrafluoroethylene resin and evenly disperse it in anhydrous ethanol, and evenly divide it into four equal parts, record them as resin solutions A, B, C and D, and add modified molybdenum disulfide, graphite and glass fiber to the resin solutions A, B and C respectively and mix them evenly; Step 3: Add resin solution A preheated to 42°C to resin solution D preheated to 42°C to obtain resin solution E, stir at 180r / min for 12min, heat to 51°C and stand for 23min; at the same time, add resin solution B and resin solution C preheated to 44°C to resin solution D, heat to 51°C and stir at 160r / min for 23min to obtain a masterbatch; Step 4: Filtering, drying and crushing the masterbatch to obtain masterbatch, and pressing and sintering the masterbatch to obtain the wear-resistant composite material; Step 5: shaping the wear-resistant composite material to obtain an inner composite material lubricating sleeve 2, a composite material anti-friction and anti-torque outer sleeve 4 and an end composite material lubricating sleeve 5; Step six: Compound the internal composite material lubricating sleeve 2, the composite material anti-friction and torque reducing outer sleeve 4 and the end composite material lubricating sleeve 5 with the alloy steel reinforced inner skeleton 3 and the torque reducing joint body 1 to obtain a wear-resistant torque reducing tool for drilling.

[0021] Embodiment 4: In some embodiments, please refer to the attached specification Figure 1-2 , a wear-resistant torque reducing tool for drilling, comprising a torque reducing joint body 1, an internal composite material lubricating sleeve 2, an alloy steel reinforced inner skeleton 3, a composite material friction reducing and torque reducing outer sleeve 4 and an end composite material lubricating sleeve 5; The outer side of the torque reducing joint body 1 is provided with a plurality of annular grooves for fitting the internal composite material lubricating sleeve 2, the outer side of the internal composite material lubricating sleeve 2 is rotatably connected to an alloy steel reinforced inner frame 3, the outer side of the alloy steel reinforced inner frame 3 is rotatably connected to a composite material friction reducing and torque reducing outer sleeve 4, and both ends of the torque reducing joint body 1 are fixedly connected to end composite material lubricating sleeves 5; The alloy steel reinforced inner skeleton 3 has the following mass percentage composition: carbon 0.01-0.15%, silicon ≤3%, manganese ≤3%, aluminum ≤0, 08%, and the balance is Fe and impurities; The torsion reducing joint body 1 is made of polytetrafluoroethylene; The internal composite material lubricating sleeve 2, the composite material anti-friction and anti-torque outer sleeve 4 and the end composite material lubricating sleeve 5 are made of wear-resistant composite materials; The wear-resistant composite material is prepared by using 48g of polytetrafluoroethylene resin as a base material and compounding 4g of graphite, 3g of glass fiber and 6g of modified molybdenum disulfide; The preparation method of the wear-resistant composite material comprises the following steps: Step 1: preparing modified molybdenum disulfide; Fly ash with a particle size of 80 μm, molybdenum disulfide powder with a particle size of 6 μm, and graphite powder with a particle size of 22 μm are uniformly mixed in a ratio of 4:18:5 to obtain a mixed powder; The mixed powder was preheated to 55° C., the mixed powder was spread to a thickness of 1.3 cm and compacted, the mixed powder was sent into a steam generating chamber, and the mixed powder was ground by isopropyl stearate at 378° C. to obtain modified molybdenum disulfide; (Principle: isopropyl stearate is used to generate modified gas through a steam generator and released through the gaps on an operating table. The operating table is arranged above the steam generator. A plurality of gaps are formed between the operating table and the first steam chamber. When the mixed powder is placed on the operating table, the modified gas contacts the lower surface of the mixed powder. Reference structure: A graphite modification device and modification method disclosed in Chinese patent CN109095465B) Step 2: Weigh 50 g of polytetrafluoroethylene resin and evenly disperse it in anhydrous ethanol, and evenly divide it into four equal parts, record them as resin solutions A, B, C and D, and add modified molybdenum disulfide, graphite and glass fiber to the resin solutions A, B and C respectively and mix them evenly; Step 3: Add resin solution A preheated to 42°C to resin solution D preheated to 42°C to obtain resin solution E, stir at 180r / min for 12min, heat to 51°C and stand for 23min; at the same time, add resin solution B and resin solution C preheated to 44°C to resin solution D, heat to 51°C and stir at 160r / min for 23min to obtain a masterbatch; Step 4: Filtering, drying and crushing the masterbatch to obtain masterbatch, and pressing and sintering the masterbatch to obtain the wear-resistant composite material; Step 5: shaping the wear-resistant composite material to obtain an inner composite material lubricating sleeve 2, a composite material anti-friction and anti-torque outer sleeve 4 and an end composite material lubricating sleeve 5; Step six: Compound the internal composite material lubricating sleeve 2, the composite material anti-friction and torque reducing outer sleeve 4 and the end composite material lubricating sleeve 5 with the alloy steel reinforced inner skeleton 3 and the torque reducing joint body 1 to obtain a wear-resistant torque reducing tool for drilling.

[0022] Comparative Example 1: A wear-resistant torque reducing tool for drilling, comprising a torque reducing joint body 1, an internal composite material lubricating sleeve 2, an alloy steel reinforced inner skeleton 3, a composite material friction reducing and torque reducing outer sleeve 4 and an end composite material lubricating sleeve 5; The outer side of the torque reducing joint body 1 is provided with a plurality of annular grooves for fitting the internal composite material lubricating sleeve 2, the outer side of the internal composite material lubricating sleeve 2 is rotatably connected to an alloy steel reinforced inner frame 3, the outer side of the alloy steel reinforced inner frame 3 is rotatably connected to a composite material friction reducing and torque reducing outer sleeve 4, and both ends of the torque reducing joint body 1 are fixedly connected to end composite material lubricating sleeves 5; The alloy steel reinforced inner skeleton 3 has the following mass percentage composition: carbon 0.01-0.15%, silicon ≤3%, manganese ≤3%, aluminum ≤0, 08%, and the balance is Fe and impurities; The torsion reducing joint body 1, the internal composite material lubricating sleeve 2, the composite material anti-friction and torsion reducing outer sleeve 4 and the end composite material lubricating sleeve 5 are all made of polytetrafluoroethylene.

[0023] Experimental Example: The friction coefficient of the composite anti-friction and torque reducing outer sleeve 4 and the alloy steel reinforced inner skeleton 3 prepared in Examples 1 to 4 and Comparative Example 1 was tested using an MCY-02 friction coefficient tester according to GB / T 10006-2021 standard. The results are as follows:

[0024] The friction coefficient between polytetrafluoroethylene and metal is about 0.4. The present invention uses polytetrafluoroethylene resin as a base material, and compound graphite, glass fiber and modified molybdenum disulfide to prepare a wear-resistant composite material, and the friction coefficient between the polytetrafluoroethylene and metal is only about 0.2. During directional well drilling, the external driving device drives the torque reducing joint body 1 to rotate, and the torque reducing joint body 1 drives the internal composite material lubricating sleeve 2 to rotate. While the internal composite material lubricating sleeve 2 rotates, friction is generated with the alloy steel reinforced inner frame 3. Since the mutual friction between the composite material friction reducing and torque reducing outer sleeve 4 and the internal composite material lubricating sleeve 2 and the alloy steel reinforced inner frame 3 (i.e., the drill string and the casing) is small, the transmission of this torsional power becomes very smooth. Especially in horizontal well and large displacement well drilling operations, it not only improves the efficiency of the drilling rig, but also improves the maximum drilling capacity of the drilling rig; on the other hand, since the mutual friction between the composite material friction reducing and torque reducing outer sleeve 4 and the internal composite material lubricating sleeve 2 and the alloy steel reinforced inner frame 3 is small, the service life of the composite material friction reducing and torque reducing outer sleeve 4, the internal composite material lubricating sleeve 2 and the alloy steel reinforced inner frame 3 is improved. In addition, since the loss of torque transmission is reduced, there is no need to increase the torsional load, which will improve the safety factor of the torque reducing joint body 1 and realize safe, high-quality and fast drilling operations.

[0025] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. Such modifications or replacements will not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A wear-resistant torque reducing tool for drilling, comprising a torque reducing joint body (1), characterized in that: It also includes an internal composite material lubricating sleeve (2), an alloy steel reinforced inner frame (3), a composite material anti-friction and anti-torsion outer sleeve (4), and an end composite material lubricating sleeve (5); The outer side of the torsion reducing joint body (1) is provided with a plurality of annular grooves for fitting the internal composite material lubricating sleeve (2) therein; the outer side of the internal composite material lubricating sleeve (2) is rotatably connected to an alloy steel reinforced inner frame (3); the outer side of the alloy steel reinforced inner frame (3) is rotatably connected to a composite material friction reducing and torsion reducing outer sleeve (4); and both ends of the torsion reducing joint body (1) are fixedly connected to end composite material lubricating sleeves (5); The internal composite material lubricating sleeve (2), the composite material anti-friction and anti-torque outer sleeve (4) and the end composite material lubricating sleeve (5) are made of wear-resistant composite material; The wear-resistant composite material is prepared by using 45-58 parts of polytetrafluoroethylene resin as a base material and compounding 3-6 parts of graphite, 1-4 parts of glass fiber and 4-8 parts of modified molybdenum disulfide; The preparation method of the wear-resistant composite material comprises the following steps: Step 1: preparing modified molybdenum disulfide; The fly ash, molybdenum disulfide powder and graphite powder are uniformly mixed in a ratio of 3-8:15-23:4-9 to obtain a mixed powder; Preheating the mixed powder to 50-70° C., spreading and compacting the mixed powder, sending the mixed powder into a steam generating chamber, and grinding the mixed powder with isopropyl stearate at 375-380° C. to obtain modified molybdenum disulfide; Step 2: Weigh 45-58 parts of polytetrafluoroethylene resin and evenly disperse them in anhydrous ethanol, and evenly divide them into four equal parts, record them as resin solutions A, B, C and D, and add modified molybdenum disulfide, graphite and glass fiber to the resin solutions A, B and C respectively and mix them evenly; Step 3: Add resin solution A to resin solution D to obtain resin solution E, stir for 10-15 minutes, heat up and stand for 20-25 minutes; at the same time, add resin solution B and resin solution C to resin solution D, heat up and stir to obtain a masterbatch; Step 4: Filter, dry and crush the masterbatch to obtain masterbatch, and press and sinter the masterbatch to obtain the wear-resistant composite material.

2. A method for preparing a wear-resistant torque-reducing tool for drilling according to claim 1, characterized in that: The following steps are involved: Step 1: preparing modified molybdenum disulfide; The fly ash, molybdenum disulfide powder and graphite powder are uniformly mixed in a ratio of 3-8:15-23:4-9 to obtain a mixed powder; Preheating the mixed powder to 50-70° C., spreading and compacting the mixed powder, sending the mixed powder into a steam generating chamber, and grinding the mixed powder with isopropyl stearate at 375-380° C. to obtain modified molybdenum disulfide; Step 2: Weigh 45-58 parts of polytetrafluoroethylene resin and evenly disperse them in anhydrous ethanol, and evenly divide them into four equal parts, record them as resin solutions A, B, C and D, and add modified molybdenum disulfide, graphite and glass fiber to the resin solutions A, B and C respectively and mix them evenly; Step 3: Add resin solution A to resin solution D to obtain resin solution E, stir for 10-15 minutes, heat to 50-52°C and stand for 20-25 minutes; at the same time, add resin solution B and resin solution C to resin solution D, heat to 50-52°C and stir for 20-25 minutes to obtain a masterbatch; Step 4: Filtering, drying and crushing the masterbatch to obtain masterbatch, and pressing and sintering the masterbatch to obtain the wear-resistant composite material; Step 5: shaping the wear-resistant composite material to obtain an internal composite material lubricating sleeve (2), a composite material friction-reducing and torque-reducing outer sleeve (4), and an end composite material lubricating sleeve (5); Step six: Compounding the internal composite material lubricating sleeve (2), the composite material anti-friction and anti-torsion outer sleeve (4) and the end composite material lubricating sleeve (5) with the alloy steel reinforced inner skeleton (3) and the anti-torsion joint body (1) to obtain a wear-resistant anti-torsion tool for drilling.

3. The method for preparing a wear-resistant torque-reducing tool for drilling according to claim 2, characterized in that: In step 1, fly ash with a particle size of 70-90 μm, molybdenum disulfide powder with a particle size of 5-10 μm, and graphite powder with a particle size of 20-30 μm are uniformly mixed in a ratio of 3-8:15-23:4-9 to obtain a mixed powder.

4. The method for preparing a wear-resistant torque-reducing tool for drilling according to claim 3, characterized in that: In step 1, the mixed powder is preheated to 50-70° C., the mixed powder is spread to a thickness of 1.2-1.5 cm and compacted, the mixed powder is sent into a steam generating chamber, and the mixed powder is ground by isopropyl stearate at 375-380° C. to obtain modified molybdenum disulfide.

5. The method for preparing a wear-resistant torque-reducing tool for drilling according to claim 4, characterized in that: Step three is specifically as follows: adding resin solution A preheated to 40-45°C to resin solution D preheated to 40-45°C to obtain resin solution E, stirring for 10-15 minutes, heating to 50-52°C and standing for 20-25 minutes; at the same time, adding resin solution B and resin solution C preheated to 40-45°C to resin solution D, heating to 50-52°C and stirring for 20-25 minutes to obtain a masterbatch.

6. The method for preparing a wear-resistant torque-reducing tool for drilling according to claim 5, characterized in that: In step 3, the stirring speed is 150-200 r / min.

7. The method for preparing a wear-resistant torque-reducing tool for drilling according to claim 6, characterized in that: The alloy steel reinforced inner skeleton (3) has the following composition by mass percentage: carbon 0.01-0.15%, silicon ≤3%, manganese ≤3%, aluminum ≤0.08%, and the remainder is Fe and impurities.

8. The method for preparing a wear-resistant torque-reducing tool for drilling according to claim 7, characterized in that: The torsion reducing joint body (1) is made of polytetrafluoroethylene.

Images