Lubricating grease as well as preparation method and application thereof

Abstract

The invention belongs to the technical field of oil extraction expansion pipe lubrication, and provides lubricating grease as well as a preparation method and application thereof. The lubricating grease is prepared from the following raw materials in percentage by mass: 30-65% of alkaline calcium sulfonate, 30-55% of base oil, 1-8% of a calcium sulfonate crystal form conversion agent and 0.5-3% of a tackifier, the kinematic viscosity of the base oil at 100 DEG C is 10-100 mm < 2 > / s; and the viscosity average molecular weight of the tackifier is 35000 to 100000. According to the lubricating grease, the base oil with relatively high viscosity and the tackifier are used, so that the adhesion performance and the water washing resistance of the lubricating grease are effectively improved, meanwhile, the lubricating grease has good high-temperature resistance and wear resistance, the friction coefficient of an expansion pipe in the expansion process can be effectively reduced, and due to the improvement of lubricating conditions, the lubricating grease has good lubricating performance. And the service life of the expansion cone is prolonged, and the risk of operation faults is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of oil production expansion pipe lubrication, and in particular to a lubricating grease and a preparation method and application thereof. Background Art

[0002] The expansion casing technology is to lower the casing to be expanded into the well, and use mechanical or hydraulic power to make the expansion tool pass through the inner hole of the expansion tube, so that it undergoes plastic deformation and expands to the designed size. It can repair the casing and seal the perforated layer to optimize water injection, gas injection or production capacity. In terms of drilling, the expansion casing technology can provide emergency plugging solutions when drilling abnormal formations such as abnormal high pressure, well leakage, water production, and collapse. In addition, the expansion casing technology can provide technical means to ensure the safety of subsequent drilling operations and the smooth drilling of the target layer, effectively increase the drilling depth, change the traditional wellbore structure, optimize drilling operations, reduce the amount of cutting of the formation and the use of cementing cement slurry, supporting pipes and drilling fluids, etc., and greatly reduce drilling costs.

[0003] The lubrication problem of expansion tubes is directly related to the difficulty of the expansion process and the mechanical properties of the expanded casing. With the development of complex wells and expansion tube technology, the contradiction between the reliability of expansion tubes and complex downhole accidents has become increasingly prominent, and lubricants and expansion tube protection have become increasingly important. During deep well operations, the temperature is as high as 160°C or even higher. The expansion tube is filled with liquid, and the expansion cone is pushed forward under the action of high-pressure liquid. During this process, there is a high contact stress between the expansion cone and the inner wall of the expansion casing, which is prone to cold welding and damage to the pipe body.

[0004] At present, the grease used in the construction of expansion tubes is commercially available molybdenum disulfide extreme pressure lithium-based grease. Although it can reduce the friction coefficient and wear of the expansion tube during the friction process, the lubrication effect is not good under high temperature conditions exceeding 160°C, that is, the high temperature resistance is poor. Summary of the invention

[0005] In view of this, the object of the present invention is to provide a lubricating grease and a preparation method and application thereof. The lubricating grease provided by the present invention has excellent high temperature resistance.

[0006] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0007] The present invention provides a lubricating grease, which is prepared from raw materials comprising the following mass percentages:

[0008] Basic calcium sulfonate 30-65%, base oil 30-55%, calcium sulfonate crystal conversion agent 1-10%, tackifier 0.5-5%;

[0009] The kinematic viscosity of the base oil at 100°C is 10 to 100 mm 2 / s;

[0010] The viscosity average molecular weight of the tackifier is 35,000 to 100,000.

[0011] Preferably, the basic calcium sulfonate includes petroleum calcium sulfonate and / or high base calcium sulfonate; the base value of the basic calcium sulfonate is greater than or equal to 400 mgKOH / g.

[0012] Preferably, the base oil comprises mineral oil and / or polyalphaolefin synthetic oil.

[0013] Preferably, the calcium sulfonate crystal form conversion agent is a mixture of n-butanol and glacial acetic acid, and in the mixture of n-butanol and glacial acetic acid, the mass ratio of n-butanol to glacial acetic acid is 1:1.

[0014] Preferably, the tackifier includes one or more of polyisobutylene, ethylene-propylene copolymer and C9 petroleum resin.

[0015] Preferably, the raw materials also include a complex calcium soap component, and based on the mass percentage of alkaline calcium sulfonate, the mass percentage of the complex calcium soap component is 0-10%, not 0%; the complex calcium soap component includes the following preparation raw materials: fatty carboxylic acid, boric acid and calcium hydroxide, the number of carbon atoms in the fatty carboxylic acid is 12-24; the molar ratio of calcium hydroxide, fatty carboxylic acid and boric acid is 1:(0.4-1):(1-1.6).

[0016] Preferably, the raw material further comprises an antioxidant, and based on the mass percentage of basic calcium sulfonate, the mass percentage of the antioxidant is 0-5%, not 0%; the antioxidant comprises one or more of diphenylamine, alkyl diphenylamine and 2,6-di-tert-butyl-p-cresol.

[0017] The present invention also provides a method for preparing the grease described in the above technical solution, comprising the following steps:

[0018] dissolving the tackifier in a portion of the base oil to obtain a tackifier solution;

[0019] After mixing part of the base oil, basic calcium sulfonate and water, a calcium sulfonate crystal form conversion agent is added to carry out a crystal form conversion reaction to obtain a crystal form conversion product;

[0020] The crystal transformation product and the thickener solution are mixed, and dehydrated and homogenized in sequence to obtain the grease.

[0021] Preferably, the temperature of the crystal conversion reaction is 80-90°C and the time is 1-5h;

[0022] The dehydration temperature is 100-160°C and the time is 0.5-2h;

[0023] The homogenization temperature is room temperature to 80° C., the homogenization method is grinding, the grinding is performed on a three-roller grinder, and the number of grinding times is 1 to 6 times.

[0024] The present invention also provides the use of the lubricating grease described in the above technical solution or the lubricating grease prepared by the preparation method described in the above technical solution in expansion tubes and ship components.

[0025] The invention provides a lubricating grease.

[0026] The lubricating grease of the present invention uses a relatively high viscosity base oil and a tackifier, which effectively improves the adhesion and water scouring resistance of the lubricating grease, and has good high temperature resistance and wear resistance, which can effectively reduce the friction coefficient of the expansion tube during the expansion process; at the same time, due to the improvement of lubrication conditions, the service life of the expansion cone is extended and the risk of operational failure is reduced. In addition to being used for expansion tubes, the lubricating grease of the present invention can also be used for lubrication and protection of ship components in marine environments.

[0027] The data of the examples show that the grease of the present invention has relatively excellent adhesion characteristics and lubrication performance at 200° C., that is, it has excellent high temperature resistance. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 The comparison curve of the water washout resistance of commercially available molybdenum disulfide grease and the grease obtained in Examples 1 to 4;

[0029] Figure 2 The photographs are of the adhesion state of the commercially available molybdenum disulfide grease and the grease obtained in Examples 1 to 4 before and after being immersed in high-temperature distilled water;

[0030] Figure 3 The friction coefficient of commercially available molybdenum disulfide grease and the grease obtained in Examples 1 to 4 is changed with the test time under the conditions of a load of 100N, a frequency of 25Hz and a temperature of 200°C;

[0031] Figure 4 3D contour diagram of the wear spot after tribological testing of commercially available molybdenum disulfide grease and the grease obtained in Examples 1 to 4. DETAILED DESCRIPTION

[0032] The present invention provides a lubricating grease, which is prepared from raw materials comprising the following mass percentages:

[0033] Basic calcium sulfonate 30-65%, base oil 30-55%, calcium sulfonate crystal conversion agent 1-10%, tackifier 0.5-5%;

[0034] The kinematic viscosity of the base oil at 100°C is 10 to 100 mm 2 / s;

[0035] The viscosity average molecular weight of the tackifier is 35,000 to 100,000.

[0036] Unless otherwise specified, the raw materials used in the present invention are preferably commercially available products.

[0037] In terms of mass percentage, the raw materials for preparing the grease provided by the present invention include 30-65% of basic calcium sulfonate, and are preferably 30%, 35%, 40%, 45%, 47%, 50%, 55%, 60%, 62% or 65%. In the present invention, the basic calcium sulfonate preferably includes petroleum calcium sulfonate and / or high base calcium sulfonate, and is more preferably high base calcium sulfonate. In the present invention, the base value of the basic calcium sulfonate is preferably greater than or equal to 400 mgKOH / g, and is more preferably 400-500 mgKOH / g. In a specific embodiment of the present invention, the high base calcium sulfonate is preferably purchased from Jinzhou Kangtai Lubricant Additive Co., Ltd., with a brand name of BD C400G and a total base value of 400-500 mgKOH / g.

[0038] Based on the mass percentage of basic calcium sulfonate, the raw materials for preparing the grease provided by the present invention include 30-55% of base oil, and specifically preferably 30%, 33%, 35%, 38%, 39%, 40%, 45%, 50% or 55%. In the present invention, the kinematic viscosity of the base oil at 100°C is 10-100 mm 2 / s, preferably 30 to 60 mm 2 / s, preferably 30mm 2 / s, 31.94mm 2 / s, 35mm 2 / s, 40mm 2 / s, 45mm 2 / s, 50mm 2 / s, 55mm 2 / s or 60mm 2 / s. In the present invention, the base oil preferably includes mineral oil and / or polyalphaolefin synthetic oil, and is more preferably mineral oil. In a specific embodiment of the present invention, the base oil is preferably base oil 150BS, purchased from IRPC, Thailand, with a kinematic viscosity of 496 mm at 40°C. 2 / s, kinematic viscosity at 100℃ is 31.94mm 2 / s. In the present invention, the viscosity of the base oil is relatively high, which improves the adhesion and water wash resistance of the grease, and also has good high temperature resistance and anti-wear performance.

[0039] Based on the mass percentage of basic calcium sulfonate, the raw materials for preparing the grease provided by the present invention include 1-10% of calcium sulfonate crystal form converter, and specifically preferably 1%, 1.5%, 1.9%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, 5%, 5.5%, 6%, 6.5%, 7%, 7.5%, 8%, 8.5%, 9%, 9.5% or 10%. In the present invention, the calcium sulfonate crystal form converter is preferably a mixture of n-butanol and glacial acetic acid, and the mass ratio of n-butanol to glacial acetic acid in the mixture of n-butanol and glacial acetic acid is preferably 1:1. In the present invention, the n-butanol is preferably used in the form of an aqueous solution of n-butanol, and the mass concentration of the aqueous solution of n-butanol is preferably 50%. In the present invention, the glacial acetic acid is preferably used in the form of an aqueous solution of glacial acetic acid, and the mass concentration of the aqueous solution of glacial acetic acid is preferably 50%. In the present invention, the calcium sulfonate crystal form converter can convert amorphous calcium carbonate in high-alkalinity calcium sulfonate into calcite-type calcium carbonate, thereby having the ability to thicken base oil.

[0040] Based on the mass percentage of basic calcium sulfonate, the raw materials for preparing the grease provided by the present invention include 0.5-5% of a tackifier, and specifically preferably 0.5%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5% or 5%. In the present invention, the viscosity-average molecular weight of the tackifier is 35000-100000, and preferably 35000, 40000, 45000, 50000, 55000, 60000, 65000, 70000, 75000, 80000, 85000, 90000, 95000 or 100000. In the present invention, the tackifier preferably includes one or more of polyisobutylene, ethylene-propylene copolymer and C9 petroleum resin, and is further preferably polyisobutylene, and more preferably medium molecular weight polyisobutylene. In a specific embodiment of the present invention, the medium molecular weight polyisobutylene is preferably purchased from Zhejiang Shunda New Materials Co., Ltd., with a brand name of SDG-8850 and a viscosity average molecular weight of 85000±5000. In the present invention, the viscosity of the tackifier is relatively high, which improves the adhesion and water wash resistance of the grease, and also has good high temperature resistance and anti-wear performance.

[0041] The raw materials for preparing the grease provided by the present invention preferably also include a complex calcium soap component. Based on the mass percentage of alkaline calcium sulfonate, the mass percentage of the complex calcium soap component is preferably 0-10%, not 0%; further preferably 0.1-10%, specifically preferably 0.1%, 0.5%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, 5%, 5.5%, 6%, 6.5%, 7%, 7.5%, 8%, 8.5%, 9%, 9.1%, 9.2%, 9.5% or 10%. In the present invention, the complex calcium soap component preferably includes the following preparation raw materials: fatty carboxylic acid, boric acid and calcium hydroxide. In the present invention, the molar ratio of calcium hydroxide, fatty carboxylic acid and boric acid is preferably 1: (0.4-1): (1-1.6), specifically preferably 1: 0.48: 1.53. In the present invention, the number of carbon atoms of the fatty carboxylic acid is preferably 12-24. In a specific embodiment of the present invention, the fatty carboxylic acid is preferably 12-hydroxystearic acid, stearic acid or octadecenoic acid, and more preferably 12-hydroxystearic acid. In the present invention, the calcium hydroxide is preferably used in the form of a calcium hydroxide aqueous suspension, and the mass concentration of the calcium hydroxide aqueous suspension is preferably 50%. In the present invention, the complex calcium soap component can effectively improve the pumping performance and extreme pressure anti-wear performance of the grease, and the prepared grease has a relatively lower cost.

[0042] The raw materials for preparing the grease provided by the present invention preferably also include an antioxidant. Based on the mass percentage of basic calcium sulfonate, the mass percentage of the antioxidant is preferably 0-5%, not 0%; more preferably 0.1-5%, specifically preferably 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%, 1.1%, 1.2%, 1.3%, 1.4%, 1.5%, 1.6%, 1.7%, 1.8%, 1.9%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5% or 5%. In the present invention, the antioxidant preferably includes one or more of diphenylamine, alkyl diphenylamine and 2,6-di-tert-butyl-p-cresol, and more preferably alkyl diphenylamine and 2,6-di-tert-butyl-p-cresol. In the present invention, the alkyl diphenylamine preferably includes butyl octyl diphenylamine. In a specific embodiment of the present invention, the antioxidant is a mixture of 2,6-di-tert-butyl-p-cresol and butyl-octyl diphenylamine, and in the mixture of 2,6-di-tert-butyl-p-cresol and butyl-octyl diphenylamine, the mass ratio of 2,6-di-tert-butyl-p-cresol to butyl-octyl diphenylamine is preferably 1:2. In the present invention, the antioxidant can improve the antioxidant performance of the grease, prevent premature oxidation decay, and extend the storage and service life.

[0043] The present invention also provides a method for preparing the grease described in the above technical solution, comprising the following steps:

[0044] dissolving the tackifier in a portion of the base oil to obtain a tackifier solution;

[0045] After mixing part of the base oil, basic calcium sulfonate and water, a calcium sulfonate crystal form conversion agent is added to carry out a crystal form conversion reaction to obtain a crystal form conversion product;

[0046] The crystal transformation product and the viscosity enhancer solution are sequentially dehydrated and homogenized to obtain the grease.

[0047] In the present invention, the tackifier is dissolved in a part of the base oil (recorded as the first part of the base oil) to obtain a tackifier solution.

[0048] In the present invention, the dissolution temperature is preferably 110-130° C., more preferably 120° C.; the dissolution time is preferably 18-22 h, more preferably 20 h, and the dissolution is preferably carried out in an oven.

[0049] In the present invention, the mass concentration of the thickener in the thickener solution is preferably 10-50%, and specifically preferably 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45% or 50%.

[0050] The invention mixes part of base oil, alkaline calcium sulfonate and water, and then adds a calcium sulfonate crystal form conversion agent to carry out a crystal form conversion reaction to obtain a crystal form conversion product.

[0051] In the present invention, the water is preferably deionized water. In the present invention, the mass ratio of the basic calcium sulfonate to water is preferably 10:1.

[0052] In the present invention, the temperature for mixing the part of base oil (referred to as the second part of base oil), basic calcium sulfonate and water is preferably room temperature, the time is preferably 30 to 60 minutes, and the mixing is preferably carried out under stirring.

[0053] In the present invention, the calcium sulfonate crystal form converter is preferably used in the form of an aqueous solution of a calcium sulfonate crystal form converter. In a specific embodiment of the present invention, when the calcium sulfonate crystal form converter is preferably a mixture of n-butanol and glacial acetic acid, the calcium sulfonate crystal form converter is preferably added in the form of an aqueous solution of n-butanol and an aqueous solution of glacial acetic acid, respectively, more preferably first adding an aqueous solution of glacial acetic acid and then adding an aqueous solution of n-butanol; after the aqueous solution of glacial acetic acid is added, the present invention preferably further comprises stirring for 5 minutes; after the aqueous solution of n-butanol is added, the present invention preferably further comprises stirring for 5 minutes. In the present invention, the mass concentration of the aqueous solution of n-butane and the aqueous solution of glacial acetic acid is preferably 50%.

[0054] In the present invention, the temperature of the crystal conversion reaction is preferably 80-90°C, the time is preferably 1-5h, and more preferably 2-3h; the crystal conversion reaction is preferably carried out under stirring. In the present invention, the crystal conversion reaction is preferably carried out in a closed reactor.

[0055] In the present invention, the crystal conversion reaction can convert the amorphous calcium carbonate in the highly basic calcium sulfonate into calcite-type calcium carbonate, thereby having the ability to thicken the base oil.

[0056] Sampling and detection are preferably performed during the crystal conversion reaction, and the detection method is preferably Fourier transform infrared spectroscopy detection; when 881-886 cm -1 When the characteristic absorption peak no longer changes, it can be considered that the crystal transformation reaction is completed.

[0057] After the crystal conversion reaction is completed, the present invention preferably does not perform any treatment to obtain the crystal conversion product.

[0058] After obtaining the crystal form conversion product, the present invention mixes the crystal form conversion product and the viscosity enhancer solution, and sequentially dehydrates and homogenizes the mixture to obtain the grease.

[0059] In the present invention, the mixing of the crystal form conversion product and the thickener solution preferably includes: adding the thickener solution to the crystal form conversion product.

[0060] After the tackifier solution is added, the present invention preferably further comprises adding a portion of base oil (referred to as the third portion of base oil), wherein the third portion of base oil is the remaining base oil calculated in the formula. In the present invention, the third portion of base oil and the first portion of base oil and the second portion of base oil together constitute the entire base oil.

[0061] In the present invention, the dehydration temperature is preferably 100-160°C, specifically preferably 100°C, 110°C, 120°C, 130°C, 140°C, 150°C or 160°C; the dehydration time is 0.5-2h, specifically preferably 0.5h, 1h, 1.5 or 2h.

[0062] In the present invention, the homogenization temperature is preferably room temperature to 80°C, more preferably 60°C; the homogenization method is preferably grinding, the grinding is preferably carried out on a three-roll grinder, and the number of grinding is preferably 1 to 6 times, more preferably 3 times.

[0063] In the present invention, when the mass percentage of the complex calcium soap component is not 0, the complex calcium soap component is preferably mixed with the crystal form conversion product and the tackifier solution, and more preferably, the crystal form conversion product and the complex calcium soap component are mixed before adding the tackifier solution. In the present invention, the complex calcium soap component is preferably added in the form of a raw material for preparation.

[0064] In a specific embodiment of the present invention, when the raw materials for preparing the composite calcium soap component include fatty carboxylic acid, boric acid and calcium hydroxide, the composite calcium soap component is preferably added in the form of calcium hydroxide aqueous suspension, boric acid and fatty carboxylic acid, more preferably first adding calcium hydroxide aqueous suspension, and then adding boric acid and fatty carboxylic acid in sequence; after the calcium hydroxide aqueous suspension is added, the present invention preferably further includes stirring for 10 minutes; after the fatty carboxylic acid is added, the present invention preferably further includes stirring for 30 minutes. In the present invention, the concentration of the calcium hydroxide aqueous suspension is preferably 50wt%.

[0065] In a specific embodiment of the present invention, the fatty carboxylic acid is preferably divided into two parts, namely, a partial fatty carboxylic acid and a residual fatty carboxylic acid, and the mass ratio of the partial fatty carboxylic acid to the residual fatty carboxylic acid is preferably 1:1; the partial fatty carboxylic acid is preferably added during the crystal conversion reaction, and it is further preferred that the partial fatty carboxylic acid is added after the addition of the calcium sulfonate crystal conversion agent is completed; the residual fatty carboxylic acid is preferably added together with boric acid and calcium hydroxide according to the above technical scheme.

[0066] In the present invention, when the mass percentage of the complex calcium soap component is not 0, it is preferred to further include saponification reaction and refining, wherein the saponification reaction is preferably carried out before dehydration, and the refining is preferably carried out after dehydration and before homogenization. In a specific embodiment of the present invention, the crystal form conversion product, the complex calcium soap component and the tackifier solution are mixed, and saponification reaction, dehydration, refining and homogenization are carried out in sequence.

[0067] In the present invention, the temperature of the saponification reaction is preferably 90 to 120° C., more preferably 95 to 110° C., and particularly preferably 99° C.; the time is preferably 1 to 3 hours, and more preferably 2 hours.

[0068] After the saponification reaction, the present invention preferably does not perform any post-treatment and directly performs dehydration.

[0069] In the present invention, the refining temperature is preferably 150-210°C, specifically preferably 150°C, 160°C, 165°C, 170°C, 180°C, 190°C, 2000°C or 210°C; the refining time is preferably 5-30 min, specifically preferably 5 min, 10 min, 15 min, 20 min, 25 min or 30 min.

[0070] In the present invention, when the mass percentage of the antioxidant is not 0, the antioxidant is preferably added before homogenization. The addition temperature of the antioxidant is preferably 90° C. After the antioxidant is added, the present invention preferably further comprises stirring for 1 hour.

[0071] In a specific embodiment of the present invention, when the preparation raw materials include an antioxidant but do not include a complex calcium soap component, the preparation method of the grease preferably includes the following steps: dissolving a thickener in a portion of the base oil to obtain a thickener solution; mixing a portion of the base oil, alkaline calcium sulfonate and water, and adding a calcium sulfonate crystal conversion agent to carry out a crystal conversion reaction to obtain a crystal conversion product; mixing the crystal conversion product and the thickener, dehydrating, adding an antioxidant, and homogenizing to obtain the grease.

[0072] In a specific embodiment of the present invention, when the preparation raw materials include a complex calcium soap component but do not include an antioxidant, the preparation method of the grease preferably includes the following steps: dissolving a thickener in a portion of the base oil to obtain a thickener solution; mixing a portion of the base oil, alkaline calcium sulfonate and water, and sequentially adding an aqueous solution of glacial acetic acid, an aqueous solution of n-butanol and 12-hydroxystearic acid to carry out a crystal conversion reaction to obtain a crystal conversion product; sequentially adding a calcium hydroxide aqueous suspension, boric acid, 12-hydroxystearic acid and a thickener solution to the crystal conversion product, and sequentially carrying out a saponification reaction, dehydration, refining and homogenization to obtain the grease.

[0073] In a specific embodiment of the present invention, when the preparation raw materials include a complex calcium soap component and an antioxidant, the preparation method of the grease preferably includes the following steps: dissolving a thickener in a portion of the base oil to obtain a thickener solution; mixing a portion of the base oil, alkaline calcium sulfonate and water, and sequentially adding an aqueous solution of glacial acetic acid, an aqueous solution of n-butanol and 12-hydroxystearic acid to carry out a crystal conversion reaction to obtain a crystal conversion product; sequentially adding a calcium hydroxide aqueous suspension, boric acid, 12-hydroxystearic acid and a thickener solution to the crystal conversion product, sequentially carrying out a saponification reaction, dehydration and refining, adding an antioxidant, and homogenizing to obtain the grease.

[0074] The present invention also provides the use of the lubricating grease described in the above technical solution or the lubricating grease prepared by the preparation method described in the above technical solution in expansion tubes and ship components.

[0075] The present invention does not specifically limit the application method of the grease, and those skilled in the art can configure it according to actual needs.

[0076] The lubricating grease provided by the present invention and its preparation method and application are described in detail below in conjunction with the embodiments, but they should not be construed as limiting the scope of protection of the present invention.

[0077] The sources of raw materials used in the following examples include:

[0078] High base synthetic calcium sulfonate was purchased from Jinzhou Kangtai Lubricant Additive Co., Ltd., with a brand name of BD C400G and a total base number of 400-500 mgKOH / g;

[0079] The base oil 150BS was purchased from IRPC, Thailand, and the kinematic viscosity at 40°C was 496 mm 2 / s, kinematic viscosity at 100℃ is 31.94mm 2 / s;

[0080] Medium molecular weight polyisobutylene was purchased from Zhejiang Shunda New Materials Co., Ltd., with the brand name SDG-8850 and a viscosity-average molecular weight of 85000±5000;

[0081] Glacial acetic acid was purchased from Xilong Scientific Co., Ltd., analytical grade;

[0082] n-Butanol was purchased from Tianjin Damao Chemical Reagent Co., Ltd. of analytical grade;

[0083] Butyl octyl diphenylamine was purchased from BASF, brand L57;

[0084] 2,6-di-tert-butyl-p-cresol was purchased from LANSESS Company with the brand name AdditinRC 7110;

[0085] Distilled water was homemade.

[0086] Example 1

[0087] 23.6 g of tackifier SDG-8850 was added to 133.4 g of 150BS base oil, and the mixture was placed in an oven and kept at 120° C. for 20 h to dissolve the tackifier in the base oil, thereby obtaining a tackifier solution for use.

[0088] 1500g of high base synthetic calcium sulfonate BD C400G, 667.6g of 150BS base oil and 150.0g of deionized water were added into a 5L atmospheric pressure reactor, and stirring was started. After stirring for 30 minutes, 30g of glacial acetic acid (diluted with 1 times the mass of deionized water) was added. After stirring for 5 minutes, 30g of n-butanol (diluted with 1 times the mass of deionized water) was added. After stirring for 5 minutes, the reactor was heated to 90°C and the crystal conversion reaction was carried out under closed conditions for 3 hours. During this period, samples were taken for Fourier transform infrared spectroscopy detection until 881-886cm -1The characteristic absorption peak no longer changes; then the thickener solution is added, the reactor is heated to 140°C for dehydration for 2 hours, after the dehydration is completed, the temperature is reduced to 90°C, 2,6-di-tert-butyl-p-cresol AdditinRC 711011.8g and butyl octyl diphenylamine L5723.6g are added, and after stirring for 1 hour, the reactor is further cooled to 60°C, and ground and homogenized on a three-roll mill for 3 times to obtain grease.

[0089] The obtained grease is 2360.0 g, which contains 1.0 wt% of a thickener and 1.5 wt% of an antioxidant.

[0090] Example 2

[0091] 31.2 g of tackifier SDG-8850 was added to 176.8 g of 150BS base oil, and the mixture was placed in an oven at 120° C. for 20 h to dissolve the tackifier in the base oil, thereby obtaining a tackifier solution for use.

[0092] 1500.0g of high base synthetic calcium sulfonate BD C400G, 866.2g of 150BS base oil and 150.0g of deionized water were added into a 5L atmospheric pressure reactor, and stirring was started. After stirring for 30 minutes, 30.0g of glacial acetic acid (diluted with 1 times the mass of deionized water) was added. After stirring for 5 minutes, 30.0g of n-butanol (diluted with 1 times the mass of deionized water) was added. After stirring for 5 minutes, 67.0g of 12-hydroxystearic acid was added. The reactor was heated to 90°C and the crystal conversion reaction was carried out under closed conditions for 3 hours. During this period, samples were taken for Fourier transform infrared spectroscopy detection until 881-886cm -1 The characteristic absorption peak no longer changes; then slowly add 68.8g of calcium hydroxide (diluted with 1 times the mass of deionized water to form a suspension), stir and mix for 10 minutes, slowly add 88.2g of boric acid and 67.0g of 12-hydroxystearic acid, stir and mix for 30 minutes, add the thickener solution and 208.0g of 150BS base oil, heat to 99°C for saponification reaction for 2h, continue to heat to 140°C for dehydration for 2h, continue to heat to 165°C for refining for 10min, the reactor temperature is reduced to 90°C, Additin RC 711015.6g, L5731.2g are added, and stirred for 1h; the reactor is further cooled to 60°C, and ground and homogenized on a three-roll mill for 3 times to obtain grease.

[0093] 3120.0 g of grease was obtained, wherein the content of tackifier was 1.0 wt % and the content of antioxidant was 1.5 wt %.

[0094] Example 3

[0095] 46.8 g of tackifier SDG-8850 was added to 265.2 g of 150BS base oil (total 312 g), and the mixture was placed in an oven at 120° C. for 20 h to dissolve the tackifier in the base oil, thereby obtaining a tackifier solution for use.

[0096] 1500.0g of high base synthetic calcium sulfonate BD C400G, 866.2g of 150BS base oil and 150.0g of deionized water were added into a 5L atmospheric pressure reactor, and stirring was started. After stirring for 30 minutes, 30.0g of glacial acetic acid (diluted with 1 times the mass of deionized water) was added. After stirring for 5 minutes, 30.0g of n-butanol (diluted with 1 times the mass of deionized water) was added. After stirring for 5 minutes, 67.0g of 12-hydroxystearic acid was added. The reactor was heated to 90°C and the crystal conversion reaction was carried out under closed conditions for 3 hours. During this period, samples were taken for Fourier transform infrared spectroscopy detection until 881-886cm -1 The characteristic absorption peak does not change. Then slowly add 68.8g calcium hydroxide (diluted with 1 times the mass of deionized water to a suspension), stir and mix for 10 minutes, slowly add 88.2g boric acid and 67.0g 12-hydroxystearic acid, stir for 30 minutes, add thickener solution and 104.0g 150BS base oil, heat to 99℃ for saponification reaction for 2h, continue to heat to 140℃ for dehydration for 2h, continue to refine at 165℃ for 10min, the reactor temperature drops to 90℃, add AdditinRC 711015.6g, L5731.2g, stir for 1h, then continue to cool the reactor to 60℃, grind and homogenize on a three-roll mill for 3 times to obtain grease.

[0097] 3120.0 g of grease was obtained, in which the content of viscosity enhancer was 1.5 wt% and the content of antioxidant was 1.5 wt%.

[0098] Example 4

[0099] 62.4 g of tackifier SDG-8850 was added to 353.6 g of 150BS base oil, and the mixture was placed in an oven at 120° C. for 20 h to dissolve the tackifier in the base oil, thereby obtaining a tackifier solution for use.

[0100] 1500.0g of high base synthetic calcium sulfonate BD C400G, 866.2g of 150BS base oil and 150.0g of deionized water were added into a 5L atmospheric pressure reactor, and stirring was started. After stirring for 30 minutes, 30.0g of glacial acetic acid (diluted with 1 times the mass of deionized water) was added. After stirring for 5 minutes, 30.0g of n-butanol (diluted with 1 times the mass of deionized water) was added. After stirring for 5 minutes, 67.0g of 12-hydroxystearic acid was added. The reactor was heated to 90°C and the crystal conversion reaction was carried out under closed conditions for 3 hours. During this period, samples were taken for Fourier transform infrared spectroscopy detection until 881-886cm-1 The characteristic absorption peak no longer changes; then slowly add 68.8g of calcium hydroxide (diluted with 1 times the mass of deionized water to make a suspension) and stir for 10 minutes, then slowly add 88.2g of boric acid and 67.0g of 12-hydroxystearic acid, stir for 30 minutes, add the thickener solution, heat to 99°C for saponification reaction for 2 hours, continue to heat to 140°C for dehydration for 2 hours, continue to heat to 165°C for refining for 10 minutes, the reactor temperature is reduced to 90°C, Additin RC 711015.6g, L5731.2g are added, and after stirring for 1 hour, the reactor temperature is continuously reduced to 60°C, and the grease is ground and homogenized 3 times on a three-roll mill to obtain grease.

[0101] 3120.0 g of grease was obtained, in which the content of thickener was 2.0 wt% and the content of antioxidant was 1.5 wt%.

[0102] Comparative Example 1

[0103] Take commercially available molybdenum disulfide extreme pressure lithium-based grease as a comparative example

[0104] Performance evaluation of the lubricating grease obtained in the examples and comparative examples

[0105] 1. Basic physical and chemical properties of grease in the examples

[0106] The basic physical and chemical properties of the greases of the embodiments and comparative examples, such as appearance, dropping point, non-working cone penetration, and copper sheet corrosion, were tested according to relevant standards. The test results are shown in Table 1.

[0107] Table 1 Performance test results of the grease obtained in the examples and comparative examples

[0108] project Example 1 Example 2 Example 3 Example 4 Comparative Example 1 Test methods Appearance brown brown brown brown black Visual inspection Dropping point, °C 330 330 330 330 196 GB / T3498-2008 Cone penetration, 0.1mm (25℃) 293 282 278 271 278 GB / T269-1991 Corrosion (T2 copper sheet, 100℃, 24h) qualified qualified qualified qualified qualified GB / T7326-1987

[0109] As can be seen from Table 1, the dropping point of the grease provided by the present invention reaches 330°C, which is much higher than the comparative MoS2 grease, indicating that the grease of the present invention can withstand a higher ambient temperature.

[0110] 2. Water-resistant performance of grease in the example

[0111] Grease water spray resistance refers to the ability of grease to resist being washed out by water under test conditions. The determination of grease water spray resistance is closely related to actual application, and is an issue that must be paid attention to when correctly selecting grease for mechanical equipment in humid environments. Taking MoS2 grease as a comparison, the grease in Example 1, the grease in Example 2, the grease in Example 3 and the grease in Example 4 were tested for water spray resistance. The test process was carried out in accordance with SH / T 0109-2004 "Determination of Grease Water Spray Resistance". The experimental conditions are a bearing speed of 600r / min±30r / min, a test temperature of 79°C, a water spray rate of 5mL / s±0.5mL / s, and a test duration of 60min. After the test, all accessories including grease were dried at 77°C±6°C for 15h. The results are as follows: Figure 1 shown.

[0112] Figure 1 The comparison curve of the water loss resistance of commercially available molybdenum disulfide grease and the grease obtained in Examples 1 to 4 is shown in FIG. Figure 1 It can be seen that compared with the molybdenum disulfide grease, the water washout loss of the grease obtained in the embodiment is greatly reduced, and it has better water resistance.

[0113] 3. Example High Temperature Adhesion Performance of Grease in Water

[0114] Cut a 20mm×40mm test piece from an expansion tube made of 15CrMo, evenly apply about 1g of grease on the surface of the test piece, put it vertically into the reactor along the inner edge of the reactor, and add 30mL of distilled water. Put the reactor into an oven, set the temperature to 200℃ and keep it for 36h. Take out the test piece after 36h, and check the state of the grease after high-temperature water immersion and its high-temperature adhesion state on the expansion tube. Taking MoS2 grease as a comparison, high-temperature water immersion tests were carried out on the grease in Example 1, the grease in Example 2, the grease in Example 3 and the grease in Example 4. The results are as follows: Figure 2 shown.

[0115] Figure 2 The following are photos of the adhesion state of commercially available molybdenum disulfide grease and the grease obtained in Examples 1 to 4 before and after immersion in high-temperature distilled water. Figure 2 It can be seen that the MoS2 grease on the surface of the steel block slipped after being soaked in high-temperature water, and the example grease had better adhesion properties under the test conditions.

[0116] 4. Tribological properties of example greases

[0117] The friction coefficient of the grease of Example 1, Example 2, Example 3 and Example 4 was tested by using an SRV-IV micro-vibration friction and wear tester produced by Optimol Grease Company of Germany at a temperature of 200°C, a frequency of 25 Hz, an amplitude of 1 mm, and a load of 100 N for 30 min. The contact mode of the friction pair was ball-disc contact, and the upper test ball used was SAE52100 steel ball (59~61HRC), the lower test plate is made of 15CrMo expansion tube material For comparison, the friction coefficient of commercially available MoS2 grease was also obtained under the same conditions. Figure 3 shown.

[0118] Figure 3 The friction coefficient of commercially available molybdenum disulfide grease and the grease obtained in Examples 1 to 4 varies with the test time under the conditions of a load of 100N, a frequency of 25Hz, and a temperature of 200°C. Figure 3 It can be seen that under high temperature conditions of 200°C, the greases of the embodiments can obtain a lower friction coefficient than the MoS2 grease and have better lubrication performance.

[0119] 5. Anti-wear performance of example grease

[0120] The wear of MoS2 grease, Example 1 grease, Example 2 grease, Example 3 grease and Example 4 grease after friction test was tested using MicroXAM 3D non-contact surface tester. Figure 4 shown.

[0121] Figure 4 3D contour diagram of wear spots after tribological tests of commercially available molybdenum disulfide grease and the grease obtained in Examples 1 to 4. Figure 4 It can be seen that under high temperature conditions of 200°C, the example grease can obtain smaller wear spots than the MoS2 grease and has better anti-wear performance.

[0122] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A lubricating grease, characterized in that: Prepared from the following raw materials in percentage by weight: Basic calcium sulfonate 30-65%, base oil 30-55%, calcium sulfonate crystal conversion agent 1-10%, tackifier 0.5-5%; The kinematic viscosity of the base oil at 100°C is 10 to 100 mm 2 / s; The viscosity average molecular weight of the tackifier is 35,000 to 100,000.

2. The lubricating grease according to claim 1, characterized in that The basic calcium sulfonate includes petroleum calcium sulfonate and / or high base calcium sulfonate; the base value of the basic calcium sulfonate is greater than or equal to 400 mgKOH / g.

3. The lubricating grease according to claim 1, characterized in that: The base oil includes mineral oil and / or polyalphaolefin synthetic oil.

4. The lubricating grease according to claim 1, characterized in that: The calcium sulfonate crystal form conversion agent is a mixture of n-butanol and glacial acetic acid, and in the mixture of n-butanol and glacial acetic acid, the mass ratio of n-butanol to glacial acetic acid is 1:

1.

5. The lubricating grease according to claim 1, characterized in that: The tackifier includes one or more of polyisobutylene, ethylene-propylene copolymer and C9 petroleum resin.

6. The lubricating grease according to claim 1, characterized in that: The raw materials also include a complex calcium soap component, and based on the mass percentage of alkaline calcium sulfonate, the mass percentage of the complex calcium soap component is 0-10%, not 0%; The complex calcium soap component comprises the following preparation raw materials: fatty carboxylic acid, boric acid and calcium hydroxide, wherein the carbon atom number of the fatty carboxylic acid is 12 to 24; and the molar ratio of the calcium hydroxide, fatty carboxylic acid and boric acid is 1:(0.4 to 1):(1 to 1.6).

7. The lubricating grease according to claim 1, characterized in that The raw materials also include an antioxidant, and based on the mass percentage of basic calcium sulfonate, the mass percentage of the antioxidant is 0-5%, not 0%; the antioxidant includes one or more of diphenylamine, alkyl diphenylamine and 2,6-di-tert-butyl-p-cresol.

8. The method for preparing the lubricating grease according to any one of claims 1 to 7, characterized in that: The following steps are involved: dissolving the tackifier in a portion of the base oil to obtain a tackifier solution; After mixing part of the base oil, basic calcium sulfonate and water, a calcium sulfonate crystal form conversion agent is added to carry out a crystal form conversion reaction to obtain a crystal form conversion product; The crystal transformation product and the thickener solution are mixed, and dehydrated and homogenized in sequence to obtain the grease.

9. The preparation method according to claim 8, characterized in that: The temperature of the crystal conversion reaction is 80-90°C and the time is 1-5h; The dehydration temperature is 100-160°C and the time is 0.5-2h; The homogenization temperature is room temperature to 80° C., the homogenization method is grinding, the grinding is performed on a three-roller grinder, and the number of grinding times is 1 to 6 times.

10. Use of the lubricating grease according to any one of claims 1 to 7 or the lubricating grease prepared by the preparation method according to any one of claims 8 to 9 in expansion tubes and ship parts.

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