Ultralow-temperature zinc-free hydraulic oil for engineering machinery in extremely cold area and preparation method of ultralow-temperature zinc-free hydraulic oil

Abstract

The invention discloses ultralow-temperature zinc-free hydraulic oil for engineering machinery in extremely cold areas and a preparation method of the ultralow-temperature zinc-free hydraulic oil. The hydraulic oil is prepared from the following raw materials in percentage by mass: 65 to 75 percent of base oil, 24 to 35 percent of a viscosity index improver, 0.3 to 1.0 percent of an anti-wear agent, 0.1 to 1.5 percent of an antioxidant, 0.01 to 0.1 percent of an anti-rust agent, 0.005 to 0.02 percent of a demulsifying agent and 0.005 to 0.02 percent of a de-foaming agent. According to the ultralow-temperature hydraulic oil for the engineering machinery in the extremely cold region, the poly-alpha-olefin and the light white oil are used as main raw materials, so that the oil product has excellent low-temperature fluidity and viscosity-temperature property. The viscosity index of the oil product is greater than 250, the kinematic viscosity under the condition of-50 DEG C is less than 1500mm < 2 > / s, the pour point is lower than-60 DEG C, and the oil product is suitable for a movable hydraulic system in the Antarctic or Arctic region. The ultralow-temperature hydraulic oil for engineering machinery in extremely cold areas can ensure that a hydraulic system has startability under the condition of-50 DEG C, can realize quick start under the condition of-40 DEG C, and is very suitable for movable hydraulic systems in extremely cold areas, especially south pole and north pole areas.

Description

Technical Field

[0001] The invention relates to an ultra-low temperature zinc-free hydraulic oil for engineering machinery in extremely cold areas and a preparation method thereof. Background Art

[0002] Conventional ultra-low temperature hydraulic oil can only ensure the smooth start-up of the hydraulic system of construction machinery within the range of -20℃ to -25℃. However, within the temperature range of -30℃ to -40℃, the kinematic viscosity of ultra-low temperature hydraulic oil will increase significantly, exceeding the viscosity limit required for the start-up of the hydraulic system, resulting in the inability of construction machinery to operate smoothly in areas with extremely low temperatures. In some extremely cold areas, such as the Antarctic and Arctic regions, the ambient temperature in winter is very low, usually at -50℃ and below. When construction machinery is used in such areas, ultra-low temperature hydraulic oil is often blended with Class III and / or Class IV base oils. However, the kinematic viscosity of the oil increases significantly under extremely cold temperature conditions, which manifests as solidification or slow flow, and does not meet the winter cold start requirements of mobile hydraulic systems. Summary of the invention

[0003] In order to at least partially solve the technical problems existing in the above-mentioned prior art, an embodiment of the present invention provides an ultra-low temperature zinc-free hydraulic oil for engineering machinery in extremely cold areas and a preparation method thereof, so that when the hydraulic oil is used in engineering machinery in extremely cold areas, it can have excellent low-temperature fluidity and viscosity-temperature properties, thereby meeting the oil demand for mobile hydraulic systems in extremely cold areas.

[0004] As one aspect of the present invention, it relates to an ultra-low temperature zinc-free hydraulic oil for engineering machinery in extremely cold areas, which comprises the following constituent raw materials, measured by mass percentage: 65-75% of base oil, 24-35% of viscosity index improver, 0.3-1.0% of antiwear agent, 0.1-1.5% of antioxidant, 0.01-0.1% of rust inhibitor, 0.005-0.02% of demulsifier, and 0.005-0.02% of defoaming agent.

[0005] In one or some possible embodiments, the base oil is selected from a base oil having a kinematic viscosity of 1.5 to 5.0 mm at 40°C. 2 / s light white oil.

[0006] In one or some possible embodiments, the viscosity index improver is selected from a material having a kinematic viscosity of 600 or 1000 mm at 100°C. 2 / s of polyalphaolefin.

[0007] In one or some possible embodiments, the poly-alpha-olefin is as shown in formula (I):

[0008] In formula (I), the value range of n is 50 to 200; and R is selected from C8 to C12 long-chain alkanes.

[0009] In one or some possible embodiments, the anti-wear agent is selected from one or more of dibutyl phosphite, tricresyl phosphate or triphenyl thiophosphate.

[0010] In one or some possible embodiments, the antioxidant is 2,6-di-tert-butyl mixed phenol and / or butyl octyl diphenylamine.

[0011] In one or some possible embodiments, the rust inhibitor is calcium dinonylnaphthalenesulfonate and / or dodecenylsuccinic acid half ester.

[0012] In one or some possible embodiments, the demulsifier is a polyether demulsifier.

[0013] In one or some possible embodiments, the defoaming agent is a silicon-based composite antifoaming agent.

[0014] In one or some possible embodiments, the kinematic viscosity of the zinc-free hydraulic oil at 40°C is 13.5-16.5 mm 2 / s, viscosity index not less than 250, pour point not exceeding -60℃.

[0015] As another aspect of the present invention, it relates to a method for preparing the ultra-low temperature zinc-free hydraulic oil for engineering machinery in extremely cold regions, which specifically comprises the following steps:

[0016] S1. Add base oil, viscosity index improver, anti-wear agent, antioxidant and rust inhibitor in sequence under stirring, and heat and mix;

[0017] S2. Under stirring conditions, continue to add demulsifier and defoamer to the mixed solution prepared in S1 in sequence to obtain ultra-low temperature zinc-free hydraulic oil.

[0018] The ultra-low temperature hydraulic oil for engineering machinery in extremely cold regions prepared by the present invention uses poly-alpha olefin and light white oil as the main raw materials, so that the oil has excellent low temperature fluidity and viscosity-temperature properties. The viscosity index of the oil is greater than 250, and the kinematic viscosity at -50°C is less than 1500mm 2 / s, pour point below -60℃, suitable for mobile hydraulic systems in Antarctic or Arctic regions.

[0019] The ultra-low temperature hydraulic oil for engineering machinery in extremely cold regions of the present invention can ensure that the hydraulic system has startability at -50°C and can achieve rapid start at -40°C, and is very suitable for mobile hydraulic systems in extremely cold regions, especially in Antarctic and Arctic regions. DETAILED DESCRIPTION

[0020] The following is a detailed description of the embodiments of the present invention: The embodiments of the present invention are implemented on the premise of the technical solution of the present invention, and detailed implementation methods and processes are given, but the protection scope of the present invention is not limited to the following embodiments. The process parameters for which specific conditions are not specified in the following embodiments are generally based on conventional conditions.

[0021] The endpoints and any values ​​of the ranges disclosed in the present invention are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of each range, the endpoint values ​​of each range and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be regarded as specifically disclosed in the present invention.

[0022] The inventors conducted experimental research with reference to patents CN111218325A and CN111019743A and found that the kinematic viscosity and viscosity-temperature properties of the ultra-low temperature hydraulic oils prepared by the two at 100°C were not as expected by the inventors. The inventors conducted experimental research with reference to patents CN109652178A, CN108977260A and CN102757841A and found that most of the above three patent documents use Class II and Class III base oils as the main raw materials for ultra-low temperature hydraulic oils, and their low-temperature fluidity at -50°C is not as expected by the inventors. Therefore, the inventors made the present invention through further research and development.

[0023] The present invention uses a polyalphaolefin viscosity index improver (hereinafter referred to as "viscosity index improver") and light white oil as the main raw materials of ultra-low temperature hydraulic oil, so that the oil product has the advantages of low pour point, good low-temperature fluidity, etc., and can be suitable for developing ultra-low temperature hydraulic oil with extremely low pour point and excellent low-temperature fluidity to meet the requirements of mobile hydraulic systems in extremely cold areas.

[0024] The present invention is further described below in conjunction with specific examples, and the protection scope of the present invention is not limited by the following examples. The sources of the materials mainly involved in the examples are shown in Table 1 below, and other materials not shown are conventional commercial products.

[0025] Table 1 Material source description

[0026]

[0027]

[0028] The hydraulic oils prepared in the following examples or comparative examples are all prepared by the following steps:

[0029] Add base oil, viscosity modifier, anti-wear agent, antioxidant and rust inhibitor to the blending kettle in sequence, heat and stir for 0.5-1 hour; then add demulsifier to the mixed liquid and stir for 0.5-1 hour; finally, add defoamer and stir for 0.5-1 hour to obtain hydraulic oil product.

[0030] Example 1

[0031] The constituent materials and contents of the zinc-free hydraulic oil of this embodiment are shown in Table 2:

[0032] Table 2 Material composition and content of Example 1

[0033]

[0034]

[0035] Example 2

[0036] The constituent materials and contents of the zinc-free hydraulic oil of this embodiment are shown in Table 3:

[0037] Table 3 Material composition and content of Example 2

[0038]

[0039] Example 3

[0040] The constituent materials and contents of the zinc-free hydraulic oil of this embodiment are shown in Table 4:

[0041] Table 4 Material composition and content of Example 3

[0042]

[0043] Example 4

[0044] The constituent materials and contents of the zinc-free hydraulic oil of this embodiment are shown in Table 5:

[0045] Table 5 Material composition and content of Example 4

[0046]

[0047]

[0048] During the experimental research, the inventor made some changes to the raw materials of hydraulic oil in order to make up for the disadvantages of hydraulic oil in extremely cold areas as much as possible. Now, the experimental objects with average or poor effects are selected as comparative examples of the present invention. The following are comparative examples 1 to 3 of the present invention.

[0049] Comparative Example 1

[0050] The constituent raw materials and contents of the zinc-free hydraulic oil of this comparative example are shown in Table 6:

[0051] Table 6 Material composition and content of comparative example 1

[0052]

[0053] Comparative Example 2

[0054] The constituent raw materials and contents of the zinc-free hydraulic oil of this comparative example are shown in Table 7:

[0055] Table 7 Comparative Example 2 Material Composition and Content

[0056]

[0057] Comparative Example 3

[0058] The constituent raw materials and contents of the zinc-free hydraulic oil of this comparative example are shown in Table 8:

[0059] Table 8 Material composition and content of comparative example 3

[0060]

[0061]

[0062] The inventors conducted the following performance tests on Examples 1 to 4 and Comparative Examples 1 to 3, and recorded the performance test results of Examples 1 to 4 and Comparative Examples 1 to 3 in the following Tables 9 and 10, respectively.

[0063] Table 9 Performance test results of Examples 1 to 4

[0064]

[0065] Table 10 Performance test results of comparative examples 1 to 3

[0066]

[0067]

[0068] Through Examples 1 to 4 and Comparative Examples 1 to 3, combined with the performance test results of Tables 9 and 10, it can be seen that when the ultra-low temperature hydraulic oil with the same 40°C kinematic viscosity is blended, the ultra-high viscosity PAO600 and light white oil are used to blend the 40°C kinematic viscosity between 13.5 and 16.5 mm 2 The kinematic viscosity of ultra-low temperature hydraulic oil at -50℃ is less than 1500mm / s 2 / s, pour point below -60℃, using ultra-high viscosity PAO600 and Class III base oil to blend with 40℃ kinematic viscosity between 13.5 and 16.5 mm 2 / s ultra-low temperature hydraulic oil has a kinematic viscosity of more than 2500mm at -50℃ 2 / s, and the pour point is significantly higher than -60℃.

[0069] By comparing Example 2 and Comparative Example 2, it can be seen that when blending ultra-low temperature hydraulic oil with the same 40°C kinematic viscosity, ultra-high viscosity PAO100 and light white oil are used to blend a 40°C kinematic viscosity of 13.5-16.5 mm 2 The kinematic viscosity of ultra-low temperature hydraulic oil at -50℃ is less than 1500mm / s 2 / s, pour point below -60℃, using traditional linear polymethyl methacrylate and light white oil to blend with a 40℃ kinematic viscosity of 13.5~16.5mm 2 The kinematic viscosity of ultra-low temperature hydraulic oil at -50℃ is close to 1500mm / s. 2 / s, but the pour point is significantly higher than -60℃.

[0070] It can be concluded that: light white oil and ultra-high viscosity PAO can be used to prepare ultra-low temperature hydraulic oil with extremely low pour point, excellent low temperature fluidity and viscosity-temperature properties; Class III base oil and ultra-high viscosity PAO as well as light white oil and linear polymethyl methacrylate cannot be used to prepare ultra-low temperature hydraulic oil with both low temperature fluidity and viscosity-temperature properties (40℃ kinematic viscosity is between 13.5 and 16.5 mm 2 / s); Ultra-high viscosity PAO can be used as a viscosity modifier to blend ultra-low temperature hydraulic oil to achieve a lower pour point and further optimize the low-temperature fluidity of the oil.

[0071] In summary, the ultra-low temperature hydraulic oil for extremely cold regions of the present invention has excellent low-temperature fluidity, viscosity-temperature performance, water separation, air release and anti-foaming properties, and is suitable for mobile hydraulic systems in extremely cold regions.

[0072] The above are only preferred feasible embodiments of the present invention, and the protection scope of the present invention is not limited thereto. Various modifications or applications made according to the above embodiments are within the protection scope of this technical solution.

[0073] Although the specific embodiments of the present invention have been described in detail, it will be understood by those skilled in the art. According to all the teachings disclosed, various modifications and replacements can be made to those details, and these changes are all within the protection scope of the present invention. The full scope of the present invention is given by the attached claims and any equivalents thereof.

Claims

1. An ultra-low temperature zinc-free hydraulic oil for engineering machinery in extremely cold regions, characterized in that: Calculated by mass percentage, the composition comprises the following raw materials: 65-75% of base oil, 24-35% of viscosity index improver, 0.3-1.0% of antiwear agent, 0.1-1.5% of antioxidant, 0.01-0.1% of rust inhibitor, 0.005-0.02% of demulsifier and 0.005-0.02% of defoaming agent.

2. The ultra-low temperature zinc-free hydraulic oil for engineering machinery in extremely cold regions according to claim 1, characterized in that: The base oil is selected from the group consisting of a base oil having a kinematic viscosity of 1.5 to 5.0 mm at 40°C. 2 / s light white oil.

3. The ultra-low temperature zinc-free hydraulic oil for engineering machinery in extremely cold regions according to claim 1, characterized in that: The viscosity index improver is selected from a material having a kinematic viscosity of 600 or 1000 mm at 100°C. 2 / s of polyalphaolefin.

4. The ultra-low temperature zinc-free hydraulic oil for engineering machinery in extremely cold regions according to claim 3, characterized in that: The poly-alpha-olefin is shown in formula (I): In formula (I), the value range of n is 50 to 200; and R is selected from C8 to C12 long-chain alkanes.

5. The ultra-low temperature zinc-free hydraulic oil for engineering machinery in extremely cold regions according to claim 1, characterized in that: The anti-wear agent is selected from one or more of dibutyl phosphite, tricresyl phosphate or triphenyl thiophosphate.

6. The ultra-low temperature zinc-free hydraulic oil for engineering machinery in extremely cold regions according to claim 1, characterized in that: The antioxidant is 2,6-di-tert-butyl mixed phenol and / or butyl octyl diphenylamine.

7. The ultra-low temperature zinc-free hydraulic oil for engineering machinery in extremely cold regions according to claim 1, characterized in that: The rust inhibitor is calcium dinonylnaphthalenesulfonate and / or dodecenylsuccinic acid half ester.

8. The ultra-low temperature zinc-free hydraulic oil for engineering machinery in extremely cold regions according to claim 1, characterized in that: The demulsifier is a polyether demulsifier.

9. The ultra-low temperature zinc-free hydraulic oil for engineering machinery in extremely cold regions according to claim 1, characterized in that: The defoaming agent is a silicon-based composite antifoaming agent.

10. The ultra-low temperature zinc-free hydraulic oil for engineering machinery in extremely cold regions according to claim 1, characterized in that: The kinematic viscosity of the zinc-free hydraulic oil at 40°C is 13.5 to 16.5 mm 2 / s, viscosity index not less than 250, pour point not exceeding -60℃.

11. A method for preparing the ultra-low temperature zinc-free hydraulic oil for engineering machinery in extremely cold regions as claimed in any one of claims 1 to 10, characterized in that: The method comprises the following steps: S1. Add base oil, viscosity index improver, anti-wear agent, antioxidant and rust inhibitor in sequence under stirring, and heat and mix; S2. Under stirring conditions, continue to add demulsifier and defoamer to the mixed solution prepared in S1 in sequence to obtain ultra-low temperature zinc-free hydraulic oil.

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