阅读说明：本技术 一种在水介质中可完全溶解的硬质合金涂层及其制备方法和应用 (Hard alloy coating capable of being completely dissolved in aqueous medium and preparation method and application thereof ) 是由 刘军 汪伟 李文戈 赵胜兰 王大江 方梦莉 王晓婉 *** 于 2019-10-12 设计创作，主要内容包括：本发明公开一种在水介质中可完全溶解的硬质合金涂层及其制备方法和应用。该硬质合金涂层由可溶合金粉和硬质合金粉组成,溶解速度适中,硬度大。其制备为：将硬质合金粉和可溶合金粉混合均匀后通过等离子喷涂、火焰喷涂或超音速喷涂工艺喷涂到工件上,即得硬质合金涂层,与基体结合好。该硬质合金涂层可应用于油气田压裂改造施工中所使用工具或零件表面的防护,施工结束后该硬质合金涂层可实现完全溶解,省去后续磨铣工序,利于返排,提高施工效率。(The invention discloses a hard alloy coating capable of being completely dissolved in an aqueous medium, and a preparation method and application thereof. The hard alloy coating consists of soluble alloy powder and hard alloy powder, and has moderate dissolving speed and high hardness. The preparation method comprises the following steps: the hard alloy powder and the soluble alloy powder are uniformly mixed and then sprayed on a workpiece through a plasma spraying, flame spraying or supersonic spraying process to obtain a hard alloy coating which is well combined with a matrix. The hard alloy coating can be applied to protection of the surfaces of tools or parts used in oil and gas field fracturing modification construction, can be completely dissolved after construction is finished, saves subsequent milling procedures, is favorable for flowback, and improves construction efficiency.)

1. The hard alloy coating capable of being completely dissolved in an aqueous medium is characterized by consisting of soluble alloy powder and hard alloy powder, wherein the volume ratio of the soluble alloy powder to the hard alloy powder is 1: 15-1: 5.

2. The cemented carbide coating fully dissolvable in an aqueous medium according to claim 1, wherein the dissolvable alloy powder is at least one of a dissolvable aluminum alloy powder, a dissolvable magnesium alloy powder; the hard alloy powder is nickel-based alloy powder or iron-based alloy powder.

3. The hard alloy coating capable of being completely dissolved in an aqueous medium according to claim 2, wherein the soluble aluminum alloy powder comprises the following components in percentage by weight: mg: 2.8% -4.2%, Cu: 1% -2%, Ga: 1% -1.8%, In: 0.2 to 0.5 percent of Al, and the balance of Al; the soluble magnesium alloy powder comprises the following components in percentage by weight: al: 5% -9%, Zn: 0.9% -1.6%, Ni: 0.2 to 1.2 percent of Mg, and the balance of Mg; the nickel-based alloy powder is Ni 60; the iron-based alloy powder is Fe 60.

4. The cemented carbide coating fully dissolvable in an aqueous medium according to claim 1, wherein the cemented carbide coating is a single layer or a multi-layer structure, wherein the cemented carbide coating components of different layers in the multi-layer structure may be the same or different.

5. The cemented carbide coating fully dissolvable in an aqueous medium according to claim 1, wherein the particle size of the soluble alloy powder and the particle size of the cemented carbide powder are both 100-350 mesh; the thickness of the hard alloy coating is 1-1.5 mm.

6. The cemented carbide coating fully soluble in aqueous media according to claim 1 wherein the soluble alloy powder has a dissolution rate of 8-80 mg/cm in a 3% KCl solution at 95 ℃ by weight²hr; the dissolving rate of the hard alloy coating in a KCl solution with the weight ratio of 3 percent at 95 ℃ is 0.008-0.028 mm/hr.

7. A method for preparing a cemented carbide coating fully dissolvable in an aqueous medium according to any of claims 1 to 6, comprising the steps of:

(1) uniformly mixing soluble alloy powder and hard alloy powder to obtain soluble hard alloy powder, and sealing and storing in vacuum;

(2) and (3) carrying out sand blasting treatment on the surface of the workpiece, spraying the soluble hard alloy powder obtained in the step (1) on the surface of the workpiece by adopting plasma spraying, flame spraying or supersonic spraying, and obtaining a hard alloy coating after the spraying is finished.

8. The production method according to claim 7,

the soluble alloy powder in the step (1) is prepared by the following steps: machining a soluble alloy block into small scraps, and grinding the scraps into powder by adopting a ball milling method, wherein the ball milling conditions are as follows: the volume ratio of the ball to the soluble alloy scraps is 1: 2-2: 1, the rotating speed of the ball mill is as follows: 100-300 revolutions per minute, the running time is: 5-8 hours;

the soluble alloy powder and the hard alloy powder in the step (1) are mixed by ball milling, wherein the ball milling conditions are as follows: the rotating speed of the ball mill is as follows: 50-80 rpm, the running time is: 5-15 minutes.

9. Use of a cemented carbide coating fully dissolvable in an aqueous medium according to any of the claims 1-6 for protection of surfaces of tools or parts used in oil and gas field fracturing modification construction.

10. Use of a cemented carbide coating according to claim 9, characterized in that: the tool is a soluble packer tool and the part is a slip part.

Technical Field

The invention belongs to the field of hard alloy coating preparation and oil-gas field development, and particularly relates to a hard alloy coating capable of being completely dissolved in an aqueous medium, and a preparation method and application thereof.

Background

A large number of oil and gas resources are distributed in the shale, and are distributed in strata with different depths, and the exploitation difficulty of the shale is high due to the characteristic of low permeability. For low-permeability oil and gas resource oil enterprises, a horizontal well multi-section hydraulic fracturing technology is mostly adopted to improve the single-well productivity. In fracturing construction, a packer (bridge plug and fracturing ball) is used for plugging a construction pipe column, and then a shale layer is fractured by adopting high-pressure fracturing fluid so as to be beneficial to oil gas transportation.

The currently and generally adopted packing tools are mostly made of insoluble materials such as steel, aluminum alloy, resin and the like. After fracturing construction is completed, the packer is drilled and milled away by a downhole drilling tool in the well, and abrasive dust is returned to the ground. Due to the difficulty of drilling and milling, abrasive dust powder and fragments are not easy to return, and oil enterprises hope to adopt a soluble packing tool to replace a traditional insoluble tool. Corrosion of the tool surface to some extent is inevitable during the run-in and fracturing operations of soluble tools, thereby affecting the safety of the use of soluble tools. In addition, the packing tool set on the casing needs to bear enough axial force (anchoring force) along the well bore direction, and the fixing of the packing tool in the well bore mainly depends on slips, and the anchoring force is mainly born by the friction force generated by embedding a ceramic (or hard alloy) block mounted on the slips on the casing. If the slips are partially dissolved in the well, the embedded ceramic and hard alloy blocks are loosened, so that the use effect of the tool is influenced; the ceramic and the hard alloy block are not soluble and are not easy to flowback, and the actual requirement is also influenced. Therefore, how to ensure the use safety and enough friction force of the soluble tool, and realize the complete dissolution of the soluble tool and the convenient flowback is a problem which needs to be solved urgently at present.

Disclosure of Invention

Aiming at the technical problems, the invention provides the hard alloy coating which can be completely dissolved in the aqueous medium, and the preparation method and the application thereof, the hard alloy coating has moderate dissolving speed and high hardness, can be applied to the protection of the surfaces of tools or parts used in the fracturing modification construction of oil and gas fields, can improve the use safety, and can be completely dissolved by self after the construction is finished, thereby being convenient for flowback.

In order to solve the problems, the invention adopts the following technical scheme:

the hard alloy coating capable of being completely dissolved in an aqueous medium consists of soluble alloy powder and hard alloy powder, wherein the volume ratio of the soluble alloy powder to the hard alloy powder is 1: 15-1: 5.

The soluble alloy powder is an alloy which can not only exert excellent mechanical properties in the aspect of metal strength and hardness, but also dissolve under the condition of an aqueous medium; the aqueous medium refers to an aqueous solution containing one or more of chloride, carbonate, sulfate, hydroxide, metal, etc. in varying amounts.

According to the scheme, the particle sizes of the soluble alloy powder and the hard alloy powder are both 100-350 meshes.

According to the scheme, the soluble alloy powder is at least one of soluble aluminum alloy powder and soluble magnesium alloy powder.

According to the scheme, the soluble aluminum alloy powder comprises the following components in percentage by weight: mg: 2.8% -4.2%, Cu: 1% -2%, Ga: 1% -1.8%, In: 0.2 to 0.5 percent of Al, and the balance of Al; the soluble magnesium alloy powder comprises the following components in percentage by weight: al: 5% -9%, Zn: 0.9% -1.6%, Ni: 0.2 to 1.2 percent of magnesium and the balance of magnesium.

According to the scheme, the dissolving rate of the soluble alloy powder in a KCl solution with the weight ratio of 3 percent at 95 ℃ is 8-80 mg/cm²hr, wherein the dissolution rate is 8-80 mg/cm²hr means that the alloy has 8-80 mg of weight corroded away in solution per unit time (hour) and per unit surface area (square centimeter).

According to the scheme, the hard alloy powder is nickel-based alloy powder or iron-based alloy powder.

According to the scheme, the nickel-based alloy powder is Ni60, and the iron-based alloy powder is Fe 60.

According to the scheme, the hard alloy coating is of a single-layer or multi-layer structure, wherein in the multi-layer structure, the hard alloy coating components of different layers can be the same or different; the multilayer structure is preferably a 2-4 layer structure.

According to the scheme, the thickness of the hard alloy coating is 1-1.5 mm.

According to the scheme, the dissolution rate of the hard alloy coating in a KCl solution with the weight ratio of 3% at 95 ℃ is 0.008-0.028 mm/hr, wherein the dissolution rate of 0.008-0.028 mm/hr means that the dissoluble thickness of the hard alloy coating per hour is 0.008-0.028 mm.

A preparation method of the hard alloy coating comprises the following specific steps:

(1) uniformly mixing soluble alloy powder and hard alloy powder to obtain soluble hard alloy powder, and sealing and storing in vacuum;

(2) and (2) carrying out sand blasting treatment on the surface of the workpiece, spraying the soluble hard alloy powder obtained in the step (1) on the surface of the workpiece by adopting plasma spraying, flame spraying or supersonic spraying in an inert gas atmosphere, and obtaining a hard alloy coating after the spraying is finished.

According to the scheme, the soluble alloy powder in the step (1) is prepared by the following steps: machining a soluble alloy block into small scraps, and grinding the scraps into powder by adopting a ball milling method, wherein the ball milling conditions are as follows: the volume ratio of the ball to the soluble alloy scraps is 1: 2-2: 1, the rotating speed of the ball mill is as follows: 100-300 revolutions per minute, the running time is: 5-8 hours.

According to the scheme, the soluble alloy powder and the hard alloy powder are mixed in the step (1) by ball milling, wherein the ball milling conditions are as follows: the rotating speed of the ball mill is as follows: 50-80 rpm, the running time is: 5-15 minutes.

According to the scheme, the volume ratio of the soluble alloy powder to the hard alloy powder in the step (1) is 1: 15-1: 5.

According to the scheme, the thickness of the hard alloy coating obtained in the step (2) is 1-1.5 mm.

The application of the hard alloy coating which can be completely dissolved in the aqueous medium is applied to the protection of the surfaces of tools or parts used in the fracturing modification construction of oil and gas fields.

According to the scheme, the tool is a soluble packing tool, and the parts are slip parts.

The invention provides a hard alloy coating which can be completely dissolved in an aqueous medium, and the hard alloy coating consists of soluble alloy and hard alloy. Soluble alloy powder is distributed around the hard alloy powder in the coating according to a certain proportion, so that the hard alloy coating has certain solubility, and the coating also has enough high hardness due to the fact that the coating also contains the hard alloy powder according to a certain proportion. Meanwhile, the content ratio of the two alloys, the solubility of the soluble alloy powder and the number of layers of the coating can be used for regulating the solubility of the hard alloy coating, and the hardness of the coating can be regulated by utilizing the types of the hard alloy and the proportion of the hard alloy in the soluble hard alloy coating. The dissolubility and the high hardness of the soluble hard alloy coating enable the coating to be applied to the protection of the surfaces of tools or parts in the fracturing modification construction of oil and gas fields. In the protection of the soluble packing tool, the soluble hard alloy coating not only ensures the hardness requirement, but also can be completely dissolved by itself, thereby being beneficial to flowback; in addition, the soluble hard alloy coating has certain roughness, and can provide anchoring force required between the packing tool and the casing when being applied to the surface of the part slip of the soluble packing tool, so that the soluble hard alloy coating can replace insoluble ceramic and hard alloy mosaic blocks, thoroughly solve the problem of backflow of the packing tool and reduce construction risk and cost. After construction is finished, the soluble hard alloy coating and the soluble packing tool can be completely dissolved by self, a subsequent milling process is omitted, and flowback is facilitated, so that the construction efficiency is improved.

The invention has the beneficial effects that:

1. the invention provides a hard alloy coating capable of being completely dissolved in an aqueous medium, which consists of soluble alloy powder and hard alloy powder, has high hardness, can be automatically dissolved in the aqueous medium, has small size of a dissolved product, can adjust the dissolving speed and the hardness, and can meet different construction requirements.

2. The hard alloy coating can be applied to the protection of the surface of a tool or a part in the fracturing modification construction of an oil and gas field, and when the hard alloy coating is applied to the surface of a soluble packer tool or a slip of the part, on one hand, the hardness requirement of the construction can be ensured, on the other hand, the required anchoring force between the packer tool and a casing can be provided, and the construction risk caused by using insoluble materials is reduced; after the construction is finished, the soluble hard alloy coating and the soluble packing tool can be completely dissolved by self, the subsequent milling procedure is saved, the flowback is facilitated, the construction efficiency is improved,

3. the invention adopts the spraying process to spray the soluble hard alloy powder on the surface of the required workpiece, and the prepared hard alloy coating has certain thickness, is continuous and uniform and is well combined with the matrix.

Drawings

The invention is described in further detail below with reference to the accompanying drawings

FIG. 1 is a scanning electron microscope image of a nickel-based alloy powder (a) having a particle size of 250 mesh and a soluble aluminum alloy powder (b) having a particle size of 200 mesh prepared by a ball milling method in example 1.

Fig. 2 shows a cemented carbide coating (a) prepared in example 1 and a product (b) of the cemented carbide coating dissolved in a KCl solution at 95 ℃ and a concentration of 3 wt.%.

FIG. 3 is a graph of the dissolution rate of the cemented carbide coating prepared in example 1 in a KCl solution at 95 ℃ and a concentration of 3 wt.%.

Detailed Description

The following is described with reference to specific experimental data.