CN116004306A - Main bearing sealing grease of shield tunneling machine and preparation method thereof - Google Patents

Description

Shield machine main bearing sealing grease and preparation method thereof

technical field

The invention relates to the technical field of grease for mechanical equipment, in particular to a main bearing sealing grease of a shield machine and a preparation method thereof.

Background technique

During the construction process of the shield machine, the cutterhead cuts the soil to excavate the tunnel, and the main bearing of the shield machine bears the axial and radial load and moment of the cutting cutterhead, and supports the rotation and transmission of the cutterhead. Therefore, the reliability, safety and life of the main bearing are very important. Since the excavation tunnel is usually located tens of meters below the ground, there is a lot of earth pressure on the excavation surface, and in order to reduce the torque of the cutter head and improve the fluidity of the soil during the excavation process, water, foam or Bentonite, so the main bearing sealing system is required to prevent external groundwater, muck, foaming agent, etc. from entering the main bearing.

The sealing system of the main bearing of the shield machine is generally composed of a labyrinth seal and a lip seal. The seals are separated by a seal spacer, and the cavity between the seals is filled with grease. The chamber of the labyrinth structure injects the main bearing sealing grease through the oil channel of the main bearing outer ring, which can effectively prevent water, foam, mud, bentonite cutting, muck cut off by the cutter head and When groundwater enters the main bearing system, it can also lubricate the sealing ring, thereby prolonging the service life of the main bearing, more effectively improving the tunneling efficiency of the shield machine, and ensuring the smooth progress of shield construction. Commonly used sealing greases use inorganic solid powders such as molybdenum disulfide, tungsten disulfide, and graphite as anti-wear agents to improve the friction resistance and lubrication performance of the product. However, this kind of antiwear agent is very prone to agglomeration in the base oil, and the addition of a slightly larger amount will lead to uneven dispersion of the effect in the antiwear agent and fail to exert its excellent performance.

With the needs of tunnel construction, there are more and more large-diameter shield machines, and higher requirements are put forward for the pressure-bearing type, friction resistance, and sealing performance of the main bearing sealing grease. Therefore, it is necessary to develop a friction-resistant performance and Sealing grease with excellent sealing performance.

Contents of the invention

Based on the above technical problems, the present invention combines various anti-wear agents and optimizes base oil and tackifier to obtain a shield machine main bearing sealing grease that is resistant to friction and has excellent sealing performance.

The first object of the present invention is to provide a sealing grease for the main bearing of a shield machine, which includes the following raw material components: 15-20 parts of base oil, 5-15 parts of tackifier, anti-rust 5-10 parts of anti-wear agent, 5-10 parts of liquid anti-wear agent, 2-6 parts of fiber, 30-50 parts of filler, 4-8 parts of organic solid anti-wear agent, 4-8 parts of inorganic solid anti-wear agent, lubricant 5 to 20 copies;

The liquid antiwear agent is 1-methyl-3-butylimidazolium hexafluorophosphate ionic liquid, 1-butyl-3-methylimidazolium tetrafluoroborate ionic liquid, 1-ethyl-3-methanol One or more of imidazolium dicyanamide salt ionic liquid and 1-ethyl-3-methylimidazolium acetate ionic liquid.

In one embodiment, the sealing grease for the main bearing of the shield machine includes the following raw material components: 18-20 parts of base oil, 8-12 parts of tackifier, 5-8 parts of anti-rust agent, 5-8 parts of liquid anti-wear agent 8 parts, 2 to 4 parts of fiber, 35 to 45 parts of filler, 4 to 6 parts of organic solid antiwear agent, 4 to 6 parts of inorganic solid antiwear agent, and 5 to 15 parts of lubricant.

In one embodiment, the base oil is one or more of rapeseed oil, polyethylene glycol, trimethylolpropane oleate, polyol ester and glycerin.

In one embodiment, the tackifier is a polar group-terminated polymer and its derivatives.

In one embodiment, the tackifier is one or more of polypropylene carbonate polyol, polyether polyol, polycaprolactone polyol and derivatives thereof.

In one embodiment, the rust inhibitor is one or more of calcium petroleum sulfonate, barium petroleum sulfonate, pentaerythritol monooleate, and stearylamine oleate.

In one embodiment, the fibers are one or more of short cotton fibers, long cotton fibers, cellulose fibers, and animal fibers.

In one embodiment, the filler is one or more of calcium carbonate, barium sulfate, talcum powder, and feldspar powder;

In one embodiment, the organic solid antiwear agent is one or more of polytetrafluoroethylene, polymethylmethacrylate, polyurethane, and triphenylphosphorothioate;

In one embodiment, the inorganic antiwear agent: one or more of molybdenum disulfide, tungsten disulfide, calcium fluoride, and niobium disulfide.

In one embodiment, the lubricant is one or more of lithium-based grease, barium-based grease, lanolin, and vulcanized lard.

The second object of the present invention is to provide a preparation method for the above-mentioned shield machine main bearing sealing grease, the preparation method comprising the following steps:

Mix base oil, tackifier, antirust agent, liquid antiwear agent and knead and stir, then add fiber and knead and stir, then add filler, organic solid antiwear agent, inorganic solid antiwear agent and grease for Knead and stir to obtain a sealed grease.

In one embodiment, the kneading and stirring time is 20-60 min.

Beneficial effects of the present invention:

The present invention combines organic, inorganic and specific types of liquid anti-wear agents, wherein the organic solid anti-wear agent has a smooth molecular profile and a low friction coefficient, and can form a transfer film with the contacted pair surface during the sliding process. Therefore, it has good lubricating properties, its surface energy is extremely low, it has excellent non-stickiness, and it is not easy to agglomerate in oil, which improves the dispersion and stability of inorganic solid antiwear agents in products; liquid antiwear agents are ionic liquids , which is adsorbed on the steel surface during the friction process and forms a boundary lubricant film. At higher temperatures, it will tribochemically interact with the steel surface to form a boundary composed of FePO ₄ or FeF ₂ with high bearing capacity and anti-wear performance. The lubricating film effectively plays the role of reducing friction and anti-wear, and the three kinds of wear-resistant agents synergistically improve the wear-resistant performance; and the sealing performance is excellent.

Detailed ways

In order to facilitate understanding of the present invention, the present invention will be described more fully below with reference to related examples. However, the present invention can be embodied in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosure of the present invention more thorough and comprehensive.

In addition, the terms "first" and "second" are used for descriptive purposes only, and cannot be interpreted as indicating or implying relative importance or implicitly specifying the quantity of indicated technical features. Thus, the features defined as "first" and "second" may explicitly or implicitly include at least one of these features. In the description of the invention, "plurality" means at least two, such as two, three, etc., unless specifically defined otherwise. In the description of the present invention, "several" means at least one, such as one, two, etc., unless otherwise specifically defined.

The words "preferably", "more preferably" etc. in the present invention refer to embodiments of the invention which may afford certain advantages, under certain circumstances. However, other embodiments may also be preferred, under the same or other circumstances. Furthermore, the recitation of one or more preferred embodiments does not imply that other embodiments are not useful, nor is it intended to exclude other embodiments from the scope of the invention.

When a numerical range is disclosed herein, such range is considered continuous and includes the minimum and maximum values of that range and every value between such minimum and maximum values. Further, when a range refers to an integer, every integer between the minimum and maximum of the range is included. Furthermore, when multiple ranges are provided to describe a feature or characteristic, the ranges may be combined. In other words, unless otherwise indicated, all ranges disclosed herein are to be understood to encompass any and all subranges subsumed therein.

All percentages, fractions and ratios are based on the total mass of the compositions of the present invention, unless otherwise specified. All weights as they pertain to listed ingredients are given at the active level and, therefore, do not include solvents or by-products that may be included in commercially available materials, unless otherwise specified. The term "mass percentage content" herein can be represented by the symbol "%". All molecular weights herein are weight average molecular weights expressed in Daltons unless otherwise indicated. All formulation and testing herein took place at a 25°C environment unless otherwise specified. Herein "comprises", "comprising", "comprising", "containing", "having" or other variations thereof are intended to cover non-closed inclusions and no distinction is made between these terms. The term "comprising" means that other steps and ingredients can be added which do not affect the end result. The compositions and methods/processes of the present invention comprise, consist of and consist essentially of the essential elements and limitations described herein and any additional or optional ingredients, components, steps or limitations described herein. No distinction is made herein between the terms "efficacy", "performance", "effect", "efficacy".

Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the technical field of the invention. The terminology used herein in the description of the present invention is only for the purpose of describing specific embodiments, and is not intended to limit the present invention. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

The first purpose of the present invention is to provide a shield machine main bearing sealing grease, which includes the following raw material components: 15-20 parts of base oil, 5-15 parts of tackifier, 5-15 parts of rust inhibitor 10 parts, 5-10 parts of liquid anti-wear agent, 2-6 parts of fiber, 30-50 parts of filler, 4-8 parts of organic solid anti-wear agent, 4-8 parts of inorganic solid anti-wear agent, 5-20 parts of lubricant share.

Preferably, the sealing grease includes the following raw material components: 18-20 parts of base oil, 8-12 parts of tackifier, 5-8 parts of anti-rust agent, 5-8 parts of liquid anti-wear agent, 2-4 parts of fiber , 35-45 parts of filler, 4-6 parts of organic solid anti-wear agent, 4-6 parts of inorganic solid anti-wear agent, and 5-15 parts of lubricant.

Preferably, the sealing grease for the main bearing of the shield machine includes the following raw material components: 20 parts of base oil, 10 parts of tackifier, 5 parts of antirust agent, 5 parts of liquid antiwear agent, 3 parts of fiber, and 40 parts of filler , 5 parts of organic solid antiwear agent, 5 parts of inorganic solid antiwear agent, 10 parts of lubricant.

The liquid antiwear agent is 1-methyl-3-butylimidazolium hexafluorophosphate ionic liquid, 1-butyl-3-methylimidazolium tetrafluoroborate ionic liquid, 1-ethyl-3-methanol One or more of imidazolium dicyanamide salt ionic liquid and 1-ethyl-3-methylimidazolium acetate ionic liquid.

In one embodiment, the base oil is one or more of rapeseed oil, polyethylene glycol, trimethylolpropane oleate, polyol ester and glycerin. Among them, polar oil is selected as the base oil, which can have good compatibility with the ionic liquid anti-wear agent, improve the stability of the sealing grease, and reduce the amount of oil separation.

In one embodiment, the tackifier is a polar group-terminated polymer and its derivatives, specifically including: polypropylene carbonate polyol, polyether polyol, polycaprolactone polyol and derivatives thereof one or more of them. The tackifier adopts polar tackifiers containing polar group hydroxyl end-blocking related polar tackifiers to increase the compatibility with polar base oils and liquid wear-resistant agents in the sealing grease system, with good storage stability and less oil separation.

By combining the above-mentioned tackifier and base oil containing polar groups, the sealing grease system has good compatibility, good storage stability and small oil separation.

In one embodiment, the rust inhibitor is one or more of calcium petroleum sulfonate, barium petroleum sulfonate, pentaerythritol monooleate, and stearylamine oleate.

In one embodiment, the fibers are one or more of short cotton fibers, long cotton fibers, cellulose fibers, and animal fibers.

In one embodiment, the filler is one or more of calcium carbonate, barium sulfate, talcum powder, and feldspar powder;

In one embodiment, the organic solid antiwear agent is one or more of polytetrafluoroethylene, polymethyl methacrylate, polyurethane, and triphenyl phosphorothioate; each of the above molecules has a smooth molecular profile and has Low friction coefficient, can form a transfer film with the contacted pair surface during the sliding process, so it has good lubricating performance, its surface energy is extremely low, it has excellent non-stickiness, it is not easy to agglomerate in oil, and it improves the solid Dispersion and stability of antiwear agents in products.

In one embodiment, the inorganic antiwear agent: one or more of molybdenum disulfide, tungsten disulfide, calcium fluoride, and niobium disulfide.

In one embodiment, the lubricant is one or more of lithium-based grease, barium-based grease, lanolin, and vulcanized lard.

The second object of the present invention is to provide a preparation method for the above-mentioned shield machine main bearing sealing grease, the preparation method comprising the following steps:

Mix base oil, tackifier, antirust agent, liquid antiwear agent and knead and stir, then add fiber and knead and stir, then add filler, organic solid antiwear agent, inorganic solid antiwear agent and grease for Knead and stir to obtain a sealed grease.

Before the preparation, the tackifier was dried in a blast drying oven at a temperature of 70°C.

In the preparation process, a double planetary mixer is used for kneading, and the material is discharged after kneading, and the obtained sealed grease is sealed and stored in a bag.

In one embodiment, the kneading and stirring time is 20-60 min, and the kneading time is preferably 30 min or 40 min.

The materials and reagents used in the following examples can be obtained from commercial sources unless otherwise specified.

The present invention is described in detail below in conjunction with specific examples, and these examples are for understanding rather than limiting the present invention.

Embodiment 1-5

The raw materials of Examples 1-5 were weighed according to the proportioning in Table 1.

Table 1 Embodiment 1～5 each raw material selection and proportioning

The preparation method is as follows:

Put the tackifier into an electric heating adjustable blast drying oven, and adjust the temperature to 70°C for later use. Quantitatively weigh base oil, filler, organic solid antiwear agent, inorganic solid antiwear agent, liquid antiwear agent, tackifier, lubricant, antirust agent, fiber by the formula of each embodiment of table 1, place in the shade spare.

Add base oil, tackifier, antirust agent, and liquid antiwear agent into a double planetary mixer for full kneading and stirring for 30 minutes, then add fiber into the double planetary mixer and continue full kneading and stirring for 30 minutes. Finally, add the filler, organic solid anti-wear agent, inorganic solid anti-wear agent, and lubricant into the double planetary mixer for full kneading and stirring for 40 minutes, and then discharge the material to obtain the main bearing sealing grease of the shield machine, which is stored in a sealed bag.

Comparative example 1～3

According to the proportioning in Table 2, the raw materials of Examples 1-5 were weighed.

Table 2 The selection and proportioning of each raw material in comparative examples 1 to 3

Put the tackifier into an electric heating adjustable blast drying oven, and adjust the temperature to 70°C for later use. Weigh raw materials such as base oil, filler, inorganic solid antiwear agent, tackifier, lubricant, lubricant, antirust agent, etc. according to the ratio in Table 2, and place in a cool place for later use.

Add base oil, tackifier, antirust agent, and liquid antiwear agent into a double planetary mixer for full kneading and stirring for 30 minutes, then add fiber into the double planetary mixer and continue full kneading and stirring for 30 minutes. Finally, add the filler, anti-wear agent, and lubricant into the double planetary mixer for full kneading and stirring for 40 minutes, and then discharge the material to obtain the sealing grease for the main bearing of the shield machine, which is stored in a sealed bag.

Performance Testing

Performance tests were carried out on the sealing greases of the shield machine main bearings obtained in Examples 1-5 and Comparative Examples 1-3, specifically including oil separation tests, wear scar diameters under loads of 392N and 745N, maximum peeling force, and under the condition of 0.28MPa Water flow loss, anti-water pressure sealing. The specific standards and test methods are shown in Table 3.

Table 3 Performance parameters of main bearing seal grease and reference standard method

According to the above-mentioned standard method, performance tests were performed on the sealing greases of the shield machine main bearings in Examples 1-5 and Comparative Examples 1-3, and the results are shown in Table 4.

Table 4 The performance test results of the main bearing seal grease of the shield machine in each embodiment and comparative examples

According to the test results, it can be seen that the sealing grease obtained in Examples 1-5 has good wear resistance, less oil separation, and the diameter of the wear scar is less than 0.9mm under the condition of a load of 745N and a time of 1h, and the lowest can reach 0.82mm. mm, treated at 100°C for 24 hours, the oil separation is less than 1.5%, and the water washout loss is small. Through the combination of various anti-wear agents, the anti-wear performance of sealing grease is synergistically increased, and other agents such as base oil and tackifier are optimized according to the type of anti-wear agent, so as to reduce the amount of oil separation and improve storage stability.

According to Comparative Examples 1 to 3, the components and contents in Comparative Example 1 are consistent with those in Example 1, the difference is that no organic solid anti-wear agent is included, and according to the performance test results, the diameter of the wear scar is significantly increased, especially Under high load conditions, the diameter of the wear scar increases significantly, the maximum peeling force decreases, and its anti-friction performance decreases, indicating that the organic solid anti-wear agent can effectively increase the anti-friction performance of the main bearing sealing grease under high load. Wherein the components and contents in Comparative Example 2 are consistent with those in Example 2, the difference is that no liquid anti-wear agent is included, according to the performance test results, the diameter of the wear scar increases, the anti-friction performance decreases, and the maximum peeling force decreases, The increase in water flow loss shows that the liquid anti-wear agent can also improve the adhesion of the main bearing seal grease while improving the friction performance. Each component and its content in comparative example 3 are consistent with embodiment 3, and its difference is that the added tackifier is polyisobutylene, and it does not end-block with polar group, in sealing grease system, tackifier polyisobutylene The compatibility with liquid anti-wear agents is poor, and it is easy to precipitate, which increases the amount of oil separation, and at the same time, the anti-friction and adhesion properties also decrease. Therefore, according to the above examples and comparative examples, it can be concluded that the sealed grease system is an organic and unified whole, and the raw materials in the system interact with each other, and through the inherent properties of the reagents and the interaction with other reagents, synergistically improve The wear resistance of the sealing grease and the good compatibility of the raw materials of the sealing grease improve the stability of the system.

The technical features of the above-mentioned embodiments can be combined arbitrarily. To make the description concise, all possible combinations of the technical features in the above-mentioned embodiments are not described. However, as long as there is no contradiction in the combination of these technical features, should be considered as within the scope of this specification.

The above-mentioned embodiments only express several implementation modes of the present invention, and the descriptions thereof are relatively specific and detailed, but should not be construed as limiting the patent scope of the invention. It should be pointed out that those skilled in the art can make several modifications and improvements without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent for the present invention should be based on the appended claims.

Claims (13)

1. A seal grease for the main bearing of a shield machine, characterized in that the seal grease for the main bearing of a shield machine comprises the following raw material components: 15 to 20 parts of base oil, 5 to 15 parts of tackifier, 5 parts of rust inhibitor ～10 parts, liquid antiwear agent 5～10 parts, fiber 2～6 parts, filler 30～50 parts, organic solid antiwear agent 4～8 parts, inorganic solid antiwear agent 4～8 parts and lubricant 5～ 20 copies; The liquid antiwear agent is 1-methyl-3-butylimidazolium hexafluorophosphate ionic liquid, 1-butyl-3-methylimidazolium tetrafluoroborate ionic liquid, 1-ethyl-3-methanol One or more of imidazolium dicyanamide salt ionic liquid and 1-ethyl-3-methylimidazolium acetate ionic liquid. 2. The sealing grease for the main bearing of the shield machine according to claim 1, characterized in that the sealing grease for the main bearing of the shield machine comprises the following raw material components: 18-20 parts of base oil, 8-12 parts of tackifier , 5-8 parts of anti-rust agent, 5-8 parts of liquid anti-wear agent, 2-4 parts of fiber, 35-45 parts of filler, 4-6 parts of organic solid anti-wear agent, 4-6 parts of inorganic solid anti-wear agent , 5 to 15 parts of lubricant. 3. The sealing grease for shield machine main bearing according to any one of claims 1-2, wherein the base oil is rapeseed oil, polyethylene glycol, trimethylolpropane oleate, multi-component One or more of alcohol esters and glycerin. 4. The sealing grease for shield machine main bearing according to any one of claims 1-2, characterized in that the tackifier is a polymer terminated with a polar group and its derivatives. 5. according to the shield machine main bearing sealing grease according to any one of claims 1-2, it is characterized in that the tackifier is polypropylene carbonate polyol, polyether polyol, polycaprolactone polyol and one or more of its derivatives. 6. according to the shield machine main bearing sealing grease according to any one of claims 1-2, it is characterized in that the rust inhibitor is calcium petroleum sulfonate, barium petroleum sulfonate, pentaerythritol monooleate, oleic acid One or more of octadecylamine. 7. The sealing grease for shield machine main bearing according to any one of claims 1-2, characterized in that, the fibers are one or more of short cotton fibers, long cotton fibers, cellulose fibers, and animal fibers . 8. The sealing grease for the main bearing of the shield machine according to any one of claims 1-2, wherein the filler is one or more of calcium carbonate, barium sulfate, talcum powder, and feldspar powder. 9. The sealing grease for shield machine main bearing according to any one of claims 1-2, characterized in that, the organic solid antiwear agent is polytetrafluoroethylene, polymethyl methacrylate, polyurethane, triphenyl one or more phosphorothioates. 10. The main bearing sealing grease of the shield machine according to any one of claims 1-2, wherein the inorganic anti-wear agent is one of molybdenum disulfide, tungsten disulfide, calcium fluoride and niobium disulfide one or more species. 11. The sealing grease for shield machine main bearing according to any one of claims 1-2, wherein the lubricant is one of lithium-based grease, barium-based grease, lanolin, and vulcanized lard or more. 12. the preparation method of shield machine main bearing sealing grease described in any one of claim 1-11, is characterized in that, described preparation method comprises the steps: Mix base oil, tackifier, antirust agent, liquid antiwear agent and knead and stir, then add fiber and knead and stir, then add filler, organic solid antiwear agent, inorganic solid antiwear agent and grease for Knead and stir to obtain a sealed grease. 13. The method for preparing the sealing grease of the main bearing of the shield machine according to claim 12, characterized in that, the kneading and stirring time is 20-60min.