Steel tooth roller bit tooth surface strengthening process

Abstract

The invention belongs to the technical field of wire machining, and particularly relates to a steel tooth roller bit tooth surface strengthening process, a roller is heated to 700 DEG C or above, and a natural gas stove or an oxyacetylene welding gun or a flame torch can be used as the heating method. Meanwhile, the hard alloy sheet to be welded is placed on a heating device such as a muffle furnace or an electric heating plate to be heated, a layer of cosolvent can be scattered on the surface of the hard alloy sheet, and the cosolvent has an anti-oxidation function. According to the method, the hard alloy block body is compounded with the tooth surface of the steel tooth, the tooth is made of steel and is integrated with the tooth wheel, so that the toughness is excellent, and the alloy block only plays a role in wear resistance and press-in.

Description

Technical Field

[0001] The invention belongs to the technical field of roller drill bits, and in particular relates to a tooth surface strengthening process for a steel tooth roller drill bit. Background Art

[0002] The roller drill bit is a commonly used tool for oil drilling. It is directly connected to the rotary top drive through the drill string or connected to the mud motor to rotate and break the rock. Common roller drill bits include insert tooth roller drill bits and steel tooth roller drill bits. The insert tooth roller drill bit directly presses the sintered tungsten carbide carbide teeth into the roller, and the alloy teeth are used as rock breaking materials. The insert tooth roller drill bit is generally used for drilling in harder formations. The steel tooth roller drill bit is processed by milling the alloy steel blank into a tooth shape, and then surfacing with wear-resistant materials, such as using oxyacetylene surfacing to weld tubular tungsten carbide wear-resistant electrodes or other wear-resistant materials. The steel tooth roller drill bit is suitable for soft formations and has a very fast drilling speed.

[0003] The insert drill bit with cemented carbide as the cutting teeth has high hardness and wear resistance, but relatively speaking, cemented carbide is brittle and the teeth are prone to chipping or breaking when the formation is uneven or cracked. At the same time, due to the limitations on the exposed tooth height and tooth shape, if the insert drill bit is used in soft formations, the penetration rate will not be as good as that of the steel tooth drill bit of the same specification even if the drill bit has long exposed teeth.

[0004] However, steel-tooth drill bits are only limited to soft formations. When the abrasiveness of the formation increases slightly, the wear rate of the teeth will increase rapidly, resulting in a decrease in the life of the drill bit. In some cases, the drill bit cannot be used after 10 to 20 hours and needs to be replaced. Summary of the invention

[0005] The purpose of the present invention is to provide a steel-tooth roller drill bit tooth surface strengthening process to solve the problems existing in the prior art.

[0006] To achieve the above object, the present invention provides the following technical solution: a steel tooth roller drill bit tooth surface strengthening process, comprising the following steps: Step 1: Heat the gear to above 700°C; Step 2: Heat the hard alloy sheet to be welded on a muffle furnace or electric heating plate heating device; Step 3: Place the solder sheet or solder paste on the tooth surface, continue to heat with acetylene, and apply flux at the same time; Step 4: After the solder sheet or solder paste is melted, use tweezers to press the carbide sheet onto the molten solder sheet. After cooling, the cladding brazing is completed.

[0007] Preferably, in step one, the heating method may use a natural gas stove, or an oxyacetylene welding gun or a flame torch.

[0008] Preferably, in step two, a layer of flux is sprinkled on the surface of the cemented carbide sheet.

[0009] A tooth surface strengthening process for a steel-tooth roller bit includes the following steps: placing a welding sheet between the tooth surface and the cemented carbide, using a heating furnace to melt the welding material according to a predetermined process, and sintering the cemented carbide and the steel-tooth surface.

[0010] The beneficial effect of the present invention is that this method composites the cemented carbide block with the steel-tooth surface. Since the tooth itself is made of steel and is integrated with the roller bit, it has excellent toughness. The alloy block only plays a role in wear resistance and pressing-in, and is supported by the steel-tooth surface itself. Therefore, the impact force received is very limited. Therefore, the grades can be made into YG8 (92% tungsten carbide, 8% cobalt) and YG6 (94% tungsten carbide, 6% cobalt). Description of the Drawings

[0011] Figure 1 Schematic diagram of the steel tooth in the present invention; Figure 2 Schematic diagram of the inlaid cemented carbide block after brazing in the present invention; Figure 3 Schematic diagram of the inlaid cemented carbide block after brazing in the present invention; Figure 4a Combination diagram of the tooth and the alloy in the present invention; Figure 4b Tooth processing diagram in the present invention; Figure 4c Alloy component diagram in the present invention; Figure 5 Schematic diagram of the roller bit after brazing in the present invention. Detailed Embodiments

[0012] It should be noted that, without conflict, the embodiments and features in the embodiments of the present invention can be combined with each other.

[0013] In the description of the present invention, it should be understood that the orientation or positional relationships indicated by the terms "center", "longitudinal", "lateral", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. are based on the orientation or positional relationships shown in the drawings. These are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation to the present invention. In addition, terms such as "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, features defined with "first", "second", etc. may explicitly or implicitly include one or more of such features. In the description of the present invention, unless otherwise stated, the meaning of "a plurality of" is two or more.

[0014] In the description of the present invention, it should be noted that unless otherwise clearly specified and limited, the terms "installation", "connection", "connection", "fixed connection", "fixed joint" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood through specific circumstances.

[0015] The following will describe in detail the specific implementation manners of the present invention in conjunction with the drawings and preferred embodiments.

[0016] As Figure 1 shown, a tooth surface strengthening process for a steel-tooth roller bit, the processing schematic of the tooth can be made into the contour shown in the figure, or other contours, hard alloy, Figure 2 in which it is made into 4 parts and can be customized for sintering. Figure 3 In which the hard alloy is made into 5 parts and can also be customized for sintering with hard alloy production enterprises.

[0017] For hard alloy blocks with specific shapes, cooperation with hard alloy manufacturers can be carried out to customize specific outer contours and grades.

[0018] After the hard alloy adheres to the tooth surface, the alloy can be welded to the surface of the steel tooth by brazing, such as using alloy sheets with low melting points, such as Ni (nickel welding sheet) sheets, and Ag (silver welding sheet) with even lower melting points, or nickel welding paste and silver welding paste.

[0019] The specific steps are as follows: Heat the cone bits to a temperature above 700 °C. The heating method can be a natural gas stove, an oxy-acetylene welding torch or a flame torch. At the same time, place the hard alloy sheets to be welded on a heating device such as a muffle furnace or a hot plate. A layer of flux can be sprinkled on the surface of the hard alloy sheets, and the flux has the function of preventing oxidation. The heating temperature is 700 °C.

[0020] Subsequently, place the welding sheet or welding paste on the tooth surface and continuously heat it with oxy-acetylene. At the same time, apply the flux. After the welding sheet or welding paste melts, use tweezers to press the alloy sheet onto the melted welding sheet. After cooling, the cladding brazing is completed.

[0021] Alternatively, a sintering method can also be used. Place the welding sheet between the tooth surface and the hard alloy, and use a heating furnace (which can be an inert atmosphere furnace or a vacuum furnace) to melt the welding material according to a predetermined process, and sinter the hard alloy and the steel tooth surface.

[0022] The tooth still uses the steel tooth as the skeleton to ensure toughness. The hard alloy of the sintered block is more wear-resistant than the wear-resistant layer built up by melting a conventional welding rod.

[0023] As Figures 4a - 4c shown, there are several other similar but not limited designs, which can be designed and manufactured according to different needs. For example, only one-time inlay brazing alloy on the tooth surface, and the gap between alloys is beneficial to the passage of downhole circulating mud during use for cooling. Adjust the layout of the alloy according to design and use experience. The following are examples but not limited to this.

[0024] This patent combines the hard alloy block with the steel tooth surface. Since the tooth itself is made of steel and is integrated with the cone bit, it has excellent toughness. The alloy block only plays a wear-resistant role and a pressing-in role, and is supported by the steel tooth surface itself. Therefore, the impact force it receives is very limited. Therefore, the grades can be made into YG8 (92% tungsten carbide, 8% cobalt) and YG6 (94% tungsten carbide, 6% cobalt).

[0025] The special groove type of the alloy tooth used to attach the hard alloy block can be machined by a milling machine, and the specific hard alloy can be sintered and made through powder and a mold.

[0026] It should be noted that for those of ordinary skill in the art in this technical field, without departing from the principle of the present invention, several improvements and refinements can still be made, and these improvements and refinements should also be regarded as the protection scope of the present invention.

Claims

1. A steel tooth roller drill bit tooth surface strengthening process, characterized in that: The following steps are involved: Step 1: Heat the gear to above 700°C; Step 2: Heat the hard alloy sheet to be welded on a muffle furnace or electric heating plate heating device; Step 3: Place the solder sheet or solder paste on the tooth surface, continue to heat with acetylene, and apply flux at the same time; Step 4: After the solder sheet or solder paste is melted, use tweezers to press the carbide sheet onto the molten solder sheet. After cooling, the cladding brazing is completed.

2. The steel-tooth roller drill bit tooth surface strengthening process according to claim 1, characterized in that: In step 1, the heating method can use a natural gas stove, an oxyacetylene welding gun or a flame torch.

3. The steel-tooth roller drill bit tooth surface strengthening process according to claim 1, characterized in that: In step 2, a layer of flux is sprinkled on the surface of the cemented carbide sheet.

4. A steel tooth roller drill bit tooth surface strengthening process, characterized in that: The following steps are involved: The welding piece is placed between the tooth surface and the cemented carbide, and a heating furnace is used to melt the welding material according to a predetermined process to sinter the cemented carbide and the tooth surface of the steel tooth.

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