阅读说明：本技术 适用于极温条件的环保型固体石墨润滑组合物、润滑剂及其制备方法 (Environment-friendly solid graphite lubricating composition suitable for extreme temperature condition, lubricant and preparation method thereof ) 是由 李云翔 李琳琼 于 2019-07-30 设计创作，主要内容包括：本发明提供了一种适用于极温条件的环保型固体石墨润滑组合物、润滑剂及其制备方法。以重量百分比计,环保型固体石墨润滑组合物包括：石墨30～50％；聚四氟乙烯粉10～30％；水性聚酰胺酰亚胺溶液10～20％；生物油脂15～30％；乳化剂5～10％；以及二硫化钼5～10％,其中水性聚酰胺酰亚胺溶液的固含量为25～35％。上述组合物中的所有组分均为环保材料,易降解；而且在低温下不易凝固；石墨、聚四氟乙烯粉和生物油脂具有高温润滑效果；水性聚酰胺酰亚胺溶液耐高温,通过控制其添加量增加润滑剂的附着力；另外乳化剂提高了石墨和聚四氟乙烯粉在体系中的分散性,二硫化钼进一步提高了该润滑剂的抗粘附性能。(The invention provides an environment-friendly solid graphite lubricating composition suitable for extreme temperature conditions, a lubricant and a preparation method thereof. The environment-friendly solid graphite lubricating composition comprises the following components in percentage by weight: 30-50% of graphite; 10-30% of polytetrafluoroethylene powder; 10-20% of a water-based polyamide-imide solution; 15-30% of biological oil; 5-10% of an emulsifier; and 5-10% of molybdenum disulfide, wherein the solid content of the aqueous polyamide-imide solution is 25-35%. All components in the composition are environment-friendly materials and are easy to degrade; and is not easy to solidify at low temperature; the graphite, the polytetrafluoroethylene powder and the biological grease have a high-temperature lubricating effect; the water-based polyamide-imide solution resists high temperature, and the adhesive force of the lubricant is increased by controlling the addition amount of the water-based polyamide-imide solution; in addition, the dispersibility of graphite and polytetrafluoroethylene powder in a system is improved by the emulsifier, and the anti-adhesion performance of the lubricant is further improved by the molybdenum disulfide.)

1. An environmentally friendly solid graphite lubricating composition suitable for use in extreme temperature conditions, the environmentally friendly solid graphite lubricating composition comprising, in weight percent:

30-50% of graphite;

10-30% of polytetrafluoroethylene powder;

10-20% of a water-based polyamide-imide solution;

15-30% of biological oil;

5-10% of an emulsifier; and

5 to 10 percent of molybdenum disulfide,

wherein the solid content of the aqueous polyamide-imide solution is 25-35%.

2. The environmentally friendly solid graphite lubricating composition of claim 1, wherein the environmentally friendly solid graphite lubricating composition comprises, in weight percent:

35-45% of graphite;

15-25% of polytetrafluoroethylene powder;

15-20% of the aqueous polyamide-imide solution;

20-30% of the biological oil;

5-10% of the emulsifier; and

and 5-10% of molybdenum disulfide.

3. The environment-friendly solid graphite lubricating composition according to claim 1 or 2, wherein the graphite is flake graphite, preferably flake graphite having a particle size of 100 to 500 mesh, and more preferably flake graphite having a particle size of 200 to 400 mesh.

4. The environmentally friendly solid graphite lubricating composition of claim 1 or 2, wherein the polytetrafluoroethylene powder is polytetrafluoroethylene micropowder.

5. The environment-friendly solid graphite lubricating composition according to claim 1 or 2, wherein the biological oil or fat is selected from any one of animal oil or fat, vegetable oil or fat and kitchen waste oil or fat, and is preferably animal oil or fat.

6. The eco-friendly solid graphite lubricating composition according to claim 1 or 2, wherein the emulsifier is selected from polyol lipid nonionic surfactants, preferably a combination of Span series surfactants selected from any one of Span20, Span40, Span60 and Span80 and Tween series surfactants selected from any one of Tween20, Tween40, Tween60 and Tween 80.

7. The environmentally friendly solid graphite lubricating composition of claim 1 or 2, further comprising 2 to 5 wt.% of ethylene glycol.

8. An environmentally friendly solid graphite lubricant suitable for use under extreme temperature conditions, characterized by being prepared using the environmentally friendly solid graphite lubricating composition of any one of claims 1 to 7.

9. The method of preparing an environmentally friendly solid graphite lubricant of claim 8, comprising mixing components of an environmentally friendly solid graphite lubricating composition to form the environmentally friendly solid graphite lubricant, preferably the method comprises:

sequentially adding polytetrafluoroethylene powder, a water-based polyamide-imide solution and an emulsifier into a mixer for first stirring to form a first mixed system;

sequentially adding graphite, molybdenum disulfide and biological oil into the first mixed system under the second stirring condition, adjusting the stirring speed after the addition is finished, stirring for the third time to obtain the environment-friendly solid graphite lubricant,

the environmentally friendly solid graphite lubricant also includes ethylene glycol, which is added after the emulsifier and before the graphite.

10. The preparation method according to claim 9, wherein the first stirring speed is 300-500 rpm and the time is 1-2 h, preferably the second stirring speed is 600-800 rpm and the time is 15-30 min; preferably, the third stirring speed is 400-550 rpm, and the time is 1-2 h.

Technical Field

The invention relates to the technical field of drilling materials, in particular to an environment-friendly solid graphite lubricating composition and a lubricant suitable for extreme temperature conditions and a preparation method thereof.

Background

In the process of drilling oil and gas wells, because the stratum contains a lot of shale, the drilling bit is easy to block the drill, the well wall is unstable, accidents such as well collapse and buried drilling occur, the abrasion of the drilling bit and the drilling tool is aggravated, and the great economic loss is caused; in the drilling process, the ground stress around the well bottom is released, and the conventional drilling fluid can increase the drilling strength of the well bottom, is not beneficial to the stable drilling of the well bottom and increases the resistance of a drilling bit; the traditional drilling fluid material is difficult to degrade, can cause pollution to a great extent on a reservoir and influence the exploitation yield of a later-period oil-gas well.

The drilling fluid lubricant is an important chemical treatment agent for the drilling fluid, and has the functions of improving the lubricating property of the drilling fluid, reducing the friction between a drilling tool and a well wall (or a casing), reducing the rotating torque and the tripping resistance of a drill string and reducing the occurrence of drilling sticking accidents. In recent years, with the continuous development and improvement of drilling technologies of deep wells, directional wells and horizontal wells, the requirements on the performance of drilling fluid lubricants are higher and higher, and the types and the quantities of the used lubricants are also higher and higher. Some lubricants in the discharged waste drilling fluid are toxic and harmful, and a considerable part of lubricants are difficult to degrade under natural conditions, so that the lubricants cause long-term retention and accumulation of the substances in the environment and pose a threat to human beings and the ecological environment. With the enhancement of environmental awareness, people pay more and more attention to environmental protection when developing novel drilling fluid lubricants.

Furthermore, with the development of the oil and gas drilling industry, drilling operations in severe cold and even extremely cold environments are more and more, and the drilling depth is also larger, so that the drilling fluid lubricant is required to have strong frost resistance before being added, and the drilling fluid lubricant is required to have high temperature resistance during the operation.

At present, drilling fluid lubricants are various in types, wherein the drilling fluid lubricants are also various in types applied at high temperature, and a patent application with the publication number of CN102277140A discloses a multifunctional solid lubricant for drilling fluid, which is prepared from the following raw materials in percentage by mass: 60-80% of expanded crystalline flake graphite, 25-35% of potassium humate, 5-10% of white oil and 5-8% of octyl phenol polyoxyethylene ether (OP-4 emulsifier) containing 4 ethoxy groups, but the white oil is easy to solidify at low temperature, so that the lubricant is difficult to add under cold conditions.

Disclosure of Invention

The invention mainly aims to provide an environment-friendly solid graphite lubricating composition suitable for extreme temperature conditions, a lubricant and a preparation method thereof, so as to solve the problem that the lubricant in the prior art is difficult to meet the use requirement under the extreme temperature conditions.

In order to achieve the above object, according to one aspect of the present invention, there is provided an eco-friendly solid graphite lubricating composition suitable for use in extreme temperature conditions, comprising, in weight percent: 30-50% of graphite; 10-30% of polytetrafluoroethylene powder; 10-20% of a water-based polyamide-imide solution; 15-30% of biological oil; 5-10% of an emulsifier; and 5-10% of molybdenum disulfide, wherein the solid content of the aqueous polyamide-imide solution is 25-35%.

Further, the environmentally friendly solid graphite lubricating composition comprises, in weight percent: 35-45% of graphite; 15-25% of polytetrafluoroethylene powder; 15-20% of a water-based polyamide-imide solution; 20-30% of biological oil; 5-10% of an emulsifier; and 5-10% of molybdenum disulfide.

Further, the graphite is flake graphite, preferably flake graphite having a particle size of 100 to 500 mesh, and more preferably flake graphite having a particle size of 200 to 400 mesh.

Further, the polytetrafluoroethylene powder is polytetrafluoroethylene ultrafine powder.

Further, the biological oil and fat is selected from any one of animal oil and fat, vegetable oil and fat, and kitchen waste oil and fat, and is preferably animal oil and fat.

Further, the emulsifier is selected from polyalcohol lipid nonionic surfactants, preferably a combination of Span series surfactants and Tween series surfactants, wherein the Span series surfactants are selected from any one of Span20, Span40, Span60 and Span80, and the Tween series surfactants are selected from any one of Tween20, Tween40, Tween60 and Tween 80.

Further, the environment-friendly solid graphite lubricating composition also comprises 2-5 wt% of ethylene glycol.

According to another aspect of the present invention, there is provided an environmentally friendly solid graphite lubricant suitable for use in extreme temperature conditions, prepared using any of the environmentally friendly solid graphite lubricating compositions described above.

According to another aspect of the present invention, there is provided a method for preparing the environmentally friendly solid graphite lubricant, wherein the method comprises mixing the components of the environmentally friendly solid graphite lubricating composition to form the environmentally friendly solid graphite lubricant, and preferably comprises: sequentially adding polytetrafluoroethylene powder, a water-based polyamide-imide solution and an emulsifier into a mixer for first stirring to form a first mixed system; and sequentially adding graphite, molybdenum disulfide and biological oil into the first mixing system under the second stirring condition, adjusting the stirring speed after the addition is finished, and stirring for the third time to obtain the environment-friendly solid graphite lubricant, wherein the environment-friendly solid graphite lubricant further comprises glycol, and the glycol is added after the emulsifier and before the graphite.

Further, the speed of the first stirring is 300-500 rpm, the time is 1-2 h, and the speed of the second stirring is preferably 600-800 rpm, and the time is 15-30 min; preferably, the third stirring speed is 400-550 rpm, and the time is 1-2 h.

By applying the technical scheme of the invention, all components are environment-friendly materials and are easy to degrade; and is not easy to solidify at low temperature, so the addition is convenient under the low-temperature operation condition; meanwhile, the graphite, the polytetrafluoroethylene powder and the biological grease have a high-temperature lubricating effect, the polytetrafluoroethylene is added in a powder form, and the addition amount of the polytetrafluoroethylene is controlled, so that on one hand, the addition and the mixing of materials are facilitated, and on the other hand, the lubricating effect at high temperature when the polytetrafluoroethylene powder is compatible with other components is improved by utilizing the self-lubricating property and the non-self-agglomeration property of the polytetrafluoroethylene powder; the water-based polyamide-imide solution is high-temperature resistant, and the adhesive force of the lubricant is increased to a certain degree by controlling the addition amount of the water-based polyamide-imide solution, so that the lubricating effect of the lubricant on a drill bit and a drilling tool is improved, and the defects that the drill bit is stuck due to the fact that the drilling resistance is increased due to too high adhesive force are avoided; in addition, the added emulsifier improves the dispersibility of graphite and polytetrafluoroethylene powder in a system, so that the lubricating effect is improved, the molybdenum disulfide has a higher lubricating coefficient, and the anti-adhesion performance of the lubricant is further improved.

Detailed Description

It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict. The present invention will be described in detail with reference to examples.

As analyzed by the background art of the application, the lubricant for drilling fluid containing paraffin or white oil in the prior art has a good lubricating effect at high temperature, but paraffin is not easily degraded and is easily solidified at low temperature, so that the lubricant is not environment-friendly and is difficult to add.

The extreme temperature refers to a high or extremely cold low temperature and a high temperature under drilling operation, such as-40 ℃ to 220 ℃.

In one exemplary embodiment of the present application, there is provided an eco-friendly solid graphite lubricating composition suitable for use in extreme temperature conditions, comprising, in weight percent: 30-50% of graphite; 10-30% of polytetrafluoroethylene powder; 10-20% of a water-based polyamide-imide solution; 15-30% of biological oil; 5-10% of an emulsifier; and 5-10% of molybdenum disulfide, wherein the solid content of the aqueous polyamide-imide solution is 25-35%.

All components in the environment-friendly solid graphite lubricating composition are environment-friendly materials and are easy to degrade; and is not easy to solidify at low temperature, so the addition is convenient under the low-temperature operation condition; meanwhile, the graphite, the polytetrafluoroethylene powder and the biological grease have a high-temperature lubricating effect, the polytetrafluoroethylene is added in a powder form, and the addition amount of the polytetrafluoroethylene is controlled, so that on one hand, the addition and the mixing of materials are facilitated, and on the other hand, the lubricating effect at high temperature when the polytetrafluoroethylene powder is compatible with other components is improved by utilizing the self-lubricating property and the non-self-agglomeration property of the polytetrafluoroethylene powder; the water-based polyamide-imide solution is high-temperature resistant, and the adhesive force of the lubricant is increased to a certain degree by controlling the addition amount of the water-based polyamide-imide solution, so that the lubricating effect of the lubricant on a drill bit and a drilling tool is improved, and the defects that the drill bit is stuck due to the fact that the drilling resistance is increased due to too high adhesive force are avoided; in addition, the added emulsifier improves the dispersibility of graphite and polytetrafluoroethylene powder in a system, so that the lubricating effect is improved, the molybdenum disulfide has a higher lubricating coefficient, and the anti-adhesion performance of the lubricant is further improved.

In one embodiment of the present application, the environmentally friendly solid graphite lubricating composition comprises, in weight percent: 35-45% of graphite; 15-25% of polytetrafluoroethylene powder; 15-20% of a water-based polyamide-imide solution; 20-30% of biological oil; 5-10% of an emulsifier; and 5-10% of molybdenum disulfide. The lubricating capability of the lubricant at high temperature is improved by further controlling the content of each component.

The graphite used for the application can be selected from commonly-used crystalline flake graphite in the field of lubricants, and according to conventional test results, the crystalline flake graphite has the advantage of better lubricating effect, but through experimental verification of the application, when being compatible with other components of the application, the crystalline flake graphite has the particle size of 100-500 meshes, the lubricating effect is more prominent, and especially the crystalline flake graphite has the particle size of 200-400 meshes.

The polytetrafluoroethylene powder of this application is commercial polytetrafluoroethylene powder, in order to utilize its self-lubricating property to improve the lubricated effect of emollient more outstandingly, prefers above-mentioned polytetrafluoroethylene powder and is polytetrafluoroethylene superfine powder.

The bio-oil used in the present application may be selected from bio-oils commonly used in the prior art, and in order to reduce costs, the bio-oil is preferably selected from any one of animal oils and fats, vegetable oils and fats, and kitchen waste oils and fats, and is preferably animal oils and fats to further improve the lubricating effect of the lubricant with the oils and fats.

The emulsifier is used for improving the mixing effect of biological grease, other solid powder and an aqueous polyamide-imide solution, and can achieve the mixing effect of the substances, preferably the emulsifier is selected from polyalcohol lipid nonionic surfactants, preferably a combination of Span series surfactants and Tween series surfactants, wherein the Span series surfactants are selected from any one of Span20, Span40, Span60 and Span80, the Tween series surfactants are selected from any one of Tween20, Tween40, Tween60 and Tween80, and experiments prove that the emulsifying effect of the mixture of Span40 and Tween60 is more prominent when the mixture is matched with the emulsifier by the weight ratio of 2: 8-5: 5, the materials are more uniformly mixed, and the lubricating effect is improved.

In addition, in order to further improve the antifreezing effect of the lubricating composition, the environment-friendly solid graphite lubricating composition preferably further comprises 2-5 wt% of ethylene glycol.

In another exemplary embodiment of the present application, there is provided an environmentally friendly solid graphite lubricant suitable for use in extreme temperature conditions, prepared using any of the environmentally friendly solid graphite lubricating compositions described above.

All components in the environment-friendly solid graphite lubricating composition are environment-friendly materials and are easy to degrade; and is not easy to solidify at low temperature, so the addition is convenient under the low-temperature operation condition; meanwhile, the graphite, the polytetrafluoroethylene powder and the biological grease have a high-temperature lubricating effect, the polytetrafluoroethylene is added in a powder form, and the addition amount of the polytetrafluoroethylene is controlled, so that on one hand, the addition and the mixing of materials are facilitated, and on the other hand, the lubricating effect at high temperature when the polytetrafluoroethylene powder is compatible with other components is improved by utilizing the self-lubricating property and the non-self-agglomeration property of the polytetrafluoroethylene powder; the water-based polyamide-imide solution is high-temperature resistant, and the adhesive force of the lubricant is increased to a certain degree by controlling the addition amount of the water-based polyamide-imide solution, so that the lubricating effect of the lubricant on a drill bit and a drilling tool is improved, and the defects that the drill bit is stuck due to the fact that the drilling resistance is increased due to too high adhesive force are avoided; in addition, the added emulsifier improves the dispersibility of graphite and polytetrafluoroethylene powder in a system, so that the lubricating effect is improved, the molybdenum disulfide has a higher lubricating coefficient, and the anti-adhesion performance of the lubricant is further improved. Based on the properties of the environment-friendly solid graphite lubricating composition, the formed environment-friendly solid graphite lubricating agent also has the properties of environment protection, low-temperature freezing prevention and lubrication at high temperature.

In another exemplary embodiment of the present application, a method for preparing the above-mentioned environmentally-friendly solid graphite lubricant is provided, the method for preparing the environmentally-friendly solid graphite lubricant comprises mixing the components of the environmentally-friendly solid graphite lubricating composition to form an environmentally-friendly solid graphite lubricant, preferably the method for preparing the environmentally-friendly solid graphite lubricant comprises sequentially adding polytetrafluoroethylene powder, an aqueous polyamideimide solution and an emulsifier into a mixer for first stirring to form a first mixed system; and sequentially adding graphite, molybdenum disulfide and biological oil into the first mixing system under the second stirring condition, adjusting the stirring speed after the addition is finished, and stirring for the third time to obtain the environment-friendly solid graphite lubricant, wherein the environment-friendly solid graphite lubricant further comprises glycol, and the glycol is added after the emulsifier and before the graphite. The materials are added in sequence according to the mode, so that the uniformity of material mixing is facilitated.

In one embodiment of the present invention, the first stirring speed is 300 to 500rpm for 1 to 2 hours, and preferably the second stirring speed is 600 to 800rpm for 15 to 30 minutes; preferably, the third stirring speed is 400-550 rpm, and the time is 1-2 h. By controlling the stirring speed and time, the uniformity of material mixing is further improved.

The advantageous effects of the present application will be further described below with reference to examples and comparative examples.