Lubricating oil for screw air compressor
By adding PAO oil, GTL oil and oxazoline borate to the lubricant of screw air compressor, the problem of lubricant difficulty in starting under low temperature environment and deterioration of oil products in high temperature and high pressure environment is solved, and better anti-wear and oxidation performance is achieved, ensuring the stable operation of the equipment and the convenience of low temperature start-up.
Patent Information
- Application Number
- CN202411961453.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-30
- Publication Date
- 2025-04-08
AI Technical Summary
The lubricant of existing screw air compressors has difficulty starting in low temperature environments, resulting in increased motor load and increased overall energy consumption. The oil deteriorates in high temperature and high pressure environments, affecting the stable operation of the equipment.
A lubricating oil consisting of PAO oil, GTL oil, oxazoline borate, etc. is used to form a mixed film through the friction chemical reaction of oxazoline borate during the friction process, reducing friction and improving anti-wear performance. At the same time, the addition of antioxidants, preservatives and other additives are added to improve the anti-oxidation and corrosion resistance of the oil.
The fluidity and starting performance of lubricant at low temperatures are improved, the service life of the equipment is extended, the anti-oxidation and wear performance of lubricant is improved, and the stability of operation and low-temperature start-up is ensured in a high-temperature and high-pressure environment.
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Figure CN119776058A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of lubricating oils, in particular to lubricating oil for a screw air compressor. Background Art
[0002] Screw air compressors are key equipment widely used in the industrial field. Screw compressors have the advantages of compact size, low mechanical vibration and continuity of compressed fluid, but the working conditions are harsh. Compressor oil, as an essential medium for compressor equipment, undertakes the functions of lubrication, sealing and cooling in the system. Many domestic and foreign products have mostly met the requirements in terms of wear resistance, high-temperature oxidation and paint film formation. It is worth noting that additives play an important role in lubricating greases, such as oxazoline and imidazoline borate, which can further improve the performance of lubricating oils. Oxazoline has good anti-wear properties, which can reduce the friction coefficient between the moving parts of the compressor, reduce wear, and thus extend the service life of the equipment; imidazoline borate performs well in anti-oxidation and anti-corrosion, which helps to maintain the stability of the lubricating oil and prevent the oil from deteriorating under high temperature and high pressure environments, thereby ensuring the stable operation of the compressor.
[0003] When the compressor is used in low-temperature areas in the north, the difficulty in starting will cause the motor load to soar, increasing the overall energy consumption of the compressor. Therefore, screw compressor lubricants with good low-temperature fluidity and containing effective additives such as oxazoline and imidazoline borate can help save energy for the compressor as a whole. While meeting the needs of industrial production, it also complies with the current pursuit of environmental protection and energy efficiency, and provides support for sustainable development. Summary of the invention
[0004] 1. Technical problems solved:
[0005] In view of the deficiencies in the prior art, the present invention provides a lubricating oil for a screw air compressor, which has antioxidant and anti-wear properties, is beneficial to the low-temperature flow performance of the equipment when starting up, and can maintain the viscosity index required for the lubrication effect during the service life.
[0006] (II) Technical solution:
[0007] A lubricating oil for a screw air compressor, comprising the following component raw materials in parts by weight: 45-58 parts by weight of PAO oil, 30-67 parts by weight of GTL oil, and 12-15.5 parts by weight of additives;
[0008] The additives include: 1.2-1.5 parts by weight of antioxidant, 1-1.2 parts by weight of preservative, 1.5-2.5 parts by weight of antiwear agent, 0.3-0.4 parts by weight of rust inhibitor, and 7-15 parts by weight of viscosity index improver.
[0009] Preferably, the PAO oil is a polyolefin synthetic base oil having a kinematic viscosity of 15-50 cst at 40°C, and the GTL oil is a GTL oil having a kinematic viscosity of 15-50 cst at 40°C.
[0010] Preferably, the antioxidant is at least one of disulfide and butylated hydroxytoluene.
[0011] Preferably, the preservative is at least one of thiocarbamate and benzotriazole.
[0012] Preferably, the rust inhibitor is at least one of barium naphthenate and barium sulfonate.
[0013] Preferably, the viscosity index improver is polymethacrylate with a molecular weight of 20,000-100,000 and a dispersion index PDI of 1.6-2.2.
[0014] Preferably, the anti-wear agent is an organic borate, and the preparation method of the organic borate is:
[0015] Step 1: Add tetrahydrofuran to a reaction vessel, then add 3-amino-1-phenyl-1,4-butanediol, sodium bicarbonate and benzoyl chloride in a molar ratio of 1:(1.4-1.6):(0.9-1.1) to the reaction vessel, react at 20-30°C for 4-6h, distill off the solvent under reduced pressure, add water, extract the organic layer with dichloromethane, dry with anhydrous magnesium sulfate, filter, and distill off the solvent under reduced pressure to obtain an amide compound.
[0016] Step 2: dissolve the amide compound in dichloromethane, add triethylamine and p-toluenesulfonyl chloride, react in an ice-water bath for 12-16 hours, warm to room temperature, and remove the solvent by distillation under reduced pressure to obtain an oxazoline intermediate.
[0017] Step 3: Add the oxazoline intermediate, boric acid and lauryl alcohol in a molar ratio of 1:(0.9-1.2):(1.8-2.2) into a reaction vessel, heat at 170-180°C for 6-8h, and distill under reduced pressure to 140-160°C after cooling to obtain oxazoline borate.
[0018] Preferably, in step 2, the molar ratio of the amide compound to p-toluenesulfonyl chloride is 1:(0.9-1.1).
[0019] (III) Beneficial technical effects: The present invention generates an oxazoline intermediate from 3-amino-1-phenyl-1,4-butanediol and benzoyl chloride, generates an oxazoline borate anti-wear agent from the oxazoline intermediate, boric acid and lauryl alcohol, and then mixes the oxazoline borate anti-wear agent with PAO oil, GTL oil, antioxidant, preservative, rust inhibitor and viscosity index improver to obtain a lubricating oil.
[0020] The present invention is used for lubricating oil of screw air compressors. The liquid oil of oxazoline borate undergoes tribochemical reaction during friction, and forms a mixed film composed of B2O3, iron oxide and nitrogen-containing organic matter on the surface of the wear spot, thereby playing a role in reducing friction and resisting wear, and has better anti-wear performance. At the same time, other additives are added to show excellent antioxidant performance, which is beneficial to the low-temperature flow performance of equipment startup and can maintain the viscosity index required for the lubrication effect during the service life. BRIEF DESCRIPTION OF THE DRAWINGS
[0021] Figure 1 This is the reaction formula for the preparation of organic borate esters. DETAILED DESCRIPTION
[0022] Embodiment 1:
[0023] (1) Add 100 mL of tetrahydrofuran to a reaction vessel, then add 30 mmol of 3-amino-1-phenyl-1,4-butanediol, 42 mmol of sodium bicarbonate and 33 mmol of benzoyl chloride to the reaction vessel, react at 20° C. for 6 h, remove the solvent by distillation under reduced pressure, add water, extract the organic layer with dichloromethane, dry with anhydrous magnesium sulfate, filter, and remove the solvent by distillation under reduced pressure to obtain an amide compound.
[0024] (2) 30 mmol of the amide compound was dissolved in 100 mL of dichloromethane, and 40 mL of triethylamine and 33 mmol of p-toluenesulfonyl chloride were added. The mixture was reacted in an ice-water bath for 16 h, and the temperature was raised to room temperature. The solvent was removed by distillation under reduced pressure to obtain an oxazoline intermediate.
[0025] (3) 10 mmol of the oxazoline intermediate, 9 mmol of boric acid and 18 mmol of lauryl alcohol were added to a reaction vessel, heated at about 170° C. for 8 h, cooled and then distilled under reduced pressure to 140° C. to obtain oxazoline borate.
[0026] (4) 45 g of polyolefin synthetic base oil PAO4, 39.5 g of GTL oil 420, 1.2 g of dibenzyl sulfide, 1 g of thiocarbamate, 2 g of oxazoline borate, 0.3 g of T746, and 11 g of polymethacrylate with a molecular weight of 51564 and a PDI of 1.86 were mixed to obtain a lubricating oil.
[0027] Embodiment 2:
[0028] (1) Add 100 mL of tetrahydrofuran to a reaction vessel, then add 30 mmol of 3-amino-1-phenyl-1,4-butanediol, 48 mmol of sodium bicarbonate and 27 mmol of benzoyl chloride to the reaction vessel, react at 30° C. for 4 h, remove the solvent by distillation under reduced pressure, add water, extract the organic layer with dichloromethane, dry with anhydrous magnesium sulfate, filter, and remove the solvent by distillation under reduced pressure to obtain an amide compound.
[0029] (2) 30 mmol of the amide compound was dissolved in 100 mL of dichloromethane, and 40 mL of triethylamine and 27 mmol of p-toluenesulfonyl chloride were added. The mixture was reacted in an ice-water bath for 12 h, and the temperature was raised to room temperature. The solvent was removed by distillation under reduced pressure to obtain an oxazoline intermediate.
[0030] (3) 10 mmol of the oxazoline intermediate, 12 mmol of boric acid and 22 mmol of lauryl alcohol were added to a reaction vessel, heated at about 180° C. for 6 h, cooled and then distilled under reduced pressure to 160° C. to obtain oxazoline borate.
[0031] (4) 20 g of polyolefin synthetic base oil PAO6, 67 g of GTL oil 420, 1.5 g of dihydroxydiphenyl sulfide, 1.1 g of dialkyl dithiocarbamate butyl ester, 2 g of oxazoline borate, 0.4 g of T746, and 8 g of polymethacrylate with a molecular weight of 65647 and a PDI of 1.71 were mixed to obtain a lubricating oil.
[0032] Embodiment 3:
[0033] (1) Add 100 mL of tetrahydrofuran to a reaction vessel, then add 30 mmol of 3-amino-1-phenyl-1,4-butanediol, 45 mmol of sodium bicarbonate and 30 mmol of benzoyl chloride to the reaction vessel, react at 20° C. for 4 h, remove the solvent by distillation under reduced pressure, add water, extract the organic layer with dichloromethane, dry with anhydrous magnesium sulfate, filter, and remove the solvent by distillation under reduced pressure to obtain an amide compound.
[0034] (2) 30 mmol of the amide compound was dissolved in 100 mL of dichloromethane, 40 mL of triethylamine and 30 mmol of p-toluenesulfonyl chloride were added, and the mixture was reacted for 12 h in an ice-water bath. The mixture was heated to room temperature and the solvent was removed by distillation under reduced pressure to obtain an oxazoline intermediate.
[0035] (3) 10 mmol of the oxazoline intermediate, 10 mmol of boric acid and 20 mmol of lauryl alcohol are added to a reaction vessel, heated at about 170° C. for 7 h, cooled and then distilled under reduced pressure to 150° C. to obtain oxazoline borate.
[0036] (4) 58 g of polyolefin synthetic base oil PAO4, 30 g of GTL oil 430, 1.5 g of dihydroxydiphenyl sulfide, 1.2 g of benzyl dialkyldithiocarbamate, 2 g of oxazoline borate, 0.3 g of T702, and 7 g of polymethacrylate with a molecular weight of 74378 and a PDI of 1.89 were mixed to obtain a lubricating oil.
[0037] Comparative Example 1:
[0038] (1) Add 100 mL of tetrahydrofuran to a reaction vessel, then add 30 mmol of 3-amino-1-phenyl-1,4-butanediol, 42 mmol of sodium bicarbonate and 33 mmol of benzoyl chloride to the reaction vessel, react at 20° C. for 6 h, remove the solvent by distillation under reduced pressure, add water, extract the organic layer with dichloromethane, dry with anhydrous magnesium sulfate, filter, and remove the solvent by distillation under reduced pressure to obtain an amide compound.
[0039] (2) 30 mmol of the amide compound was dissolved in 100 mL of dichloromethane, and 40 mL of triethylamine and 33 mmol of p-toluenesulfonyl chloride were added. The mixture was reacted in an ice-water bath for 16 h, and the temperature was raised to room temperature. The solvent was removed by distillation under reduced pressure to obtain an oxazoline intermediate.
[0040] (3) 10 mmol of the oxazoline intermediate, 9 mmol of boric acid and 18 mmol of lauryl alcohol were added to a reaction vessel, heated at about 170° C. for 8 h, cooled and then distilled under reduced pressure to 140° C. to obtain oxazoline borate.
[0041] (4) 84.5 g of polyolefin synthetic base oil PAO4, 1.2 g of dibenzyl sulfide, 1 g of thiocarbamate, 2 g of oxazoline borate, 0.3 g of T746, and 11 g of polymethacrylate with a molecular weight of 51564 and a PDI of 1.68 were mixed to obtain a lubricating oil.
[0042] Comparative Example 2:
[0043] (1) Add 100 mL of tetrahydrofuran to a reaction vessel, then add 30 mmol of 3-amino-1-phenyl-1,4-butanediol, 42 mmol of sodium bicarbonate and 33 mmol of benzoyl chloride to the reaction vessel, react at 20° C. for 6 h, remove the solvent by distillation under reduced pressure, add water, extract the organic layer with dichloromethane, dry with anhydrous magnesium sulfate, filter, and remove the solvent by distillation under reduced pressure to obtain an amide compound.
[0044] (2) 30 mmol of the amide compound was dissolved in 100 mL of dichloromethane, and 40 mL of triethylamine and 33 mmol of p-toluenesulfonyl chloride were added. The mixture was reacted in an ice-water bath for 16 h, and the temperature was raised to room temperature. The solvent was removed by distillation under reduced pressure to obtain an oxazoline intermediate.
[0045] (3) 10 mmol of the oxazoline intermediate, 9 mmol of boric acid and 18 mmol of lauryl alcohol were added to a reaction vessel, heated at about 170° C. for 8 h, cooled and then distilled under reduced pressure to 140° C. to obtain oxazoline borate.
[0046] (4) 87 g of GTL oil 420, 1.5 g of dihydroxydiphenyl sulfide, 1.1 g of dialkyldithiocarbamate butyl ester, 2 g of oxazoline borate, and 9 g of polymethacrylate with a molecular weight of 150,000 and a PDI of 2.3 were mixed to obtain a lubricating oil.
[0047] Comparative Example 3:
[0048] (1) Add 100 mL of tetrahydrofuran to a reaction vessel, then add 30 mmol of 3-amino-1-phenyl-1,4-butanediol, 42 mmol of sodium bicarbonate and 33 mmol of benzoyl chloride to the reaction vessel, react at 20° C. for 6 h, remove the solvent by distillation under reduced pressure, add water, extract the organic layer with dichloromethane, dry with anhydrous magnesium sulfate, filter, and remove the solvent by distillation under reduced pressure to obtain an amide compound.
[0049] (2) 30 mmol of the amide compound was dissolved in 100 mL of dichloromethane, and 40 mL of triethylamine and 33 mmol of p-toluenesulfonyl chloride were added. The mixture was reacted in an ice-water bath for 16 h, and the temperature was raised to room temperature. The solvent was removed by distillation under reduced pressure to obtain an oxazoline intermediate.
[0050] (3) 10 mmol of the oxazoline intermediate, 9 mmol of boric acid and 18 mmol of lauryl alcohol were added to a reaction vessel, heated at about 170° C. for 8 h, cooled and then distilled under reduced pressure to 140° C. to obtain oxazoline borate.
[0051] (4) 45 g of polyolefin synthetic base oil PAO4, 39.5 g of GTL oil 420, 1.2 g of dibenzyl sulfide, 1 g of thiocarbamate, 2 g of phosphate, 0.3 g of T746, and 11 g of polymethacrylate with a molecular weight of 51564 and a PDI of 1.68 were mixed to obtain a lubricating oil.
[0052] According to GB / T265-1988, the kinematic viscosity test was carried out at 40°C for the products of the examples and comparative examples.
[0053] According to GB / T1995-1998, the viscosity index test was carried out on the products of the embodiments and comparative examples.
[0054] According to GB / T3535-2006, the pour point test was carried out on the products of the embodiments and comparative examples.
[0055] According to GB / T7305-2003, the demulsification time test was carried out at 54°C for the products of the examples and comparative examples.
[0056] According to SH / T0193-2022, a rotating oxygen bomb test was performed on the products of the embodiments and comparative examples.
[0057] According to GB / T5096-2017, for the products of the embodiments and comparative examples, the copper sheet was corroded at 100°C for 3 hours and the corrosion level test was performed.
[0058] According to GB / T264-1983, the total acid value test was performed on the products of the embodiments and comparative examples.
[0059] According to GB / T1995-1998, the oil viscosity index test was performed on the products of the embodiments and comparative examples after running for 4000 hours.
[0060] The anti-wear properties of liquid paraffin containing different mass fractions of additives were evaluated by a four-ball friction and wear tester. The steel ball was made of GCr15 and had a diameter of 12.7 mm. The rotation speed was 1450 r / min and the test time was 30 min. After the room temperature test, the steel balls were ultrasonically cleaned in distilled water and petroleum ether for 5 min respectively. The wear spot diameter (WSD) and the maximum no-seizure load P of the three lower test balls were measured under a load of 392 N using a reading microscope (accuracy 0.01 mm). B The average value of the three test results was taken as the test data.
[0061] Table 1 Performance test results of embodiments and comparative examples
[0062]
[0063]
[0064] From the data in Table 1 above, it can be seen that the special oil for screw air compressors of the present invention has obvious advantages in the following aspects:
[0065] (1) Better low-temperature performance: The pour point of the embodiment of the present invention is significantly lower than that of Comparative Examples 1-2, because Comparative Example 2 uses a common polymethacrylate tackifier. This indicates that the embodiment of the present invention using a tackifier with a pour point depressing function has better low-temperature performance, which is beneficial to the low-temperature start-up of the compressor.
[0066] (2) Longer oxidation life: The rotating oxygen bomb test time of the embodiment of the present invention is significantly longer than that of the comparative example. After long-term operation, the viscosity index of the sample decreases slightly, indicating that the oil can maintain the viscosity level after long-term operation, thereby ensuring high and low temperature lubrication performance. However, after 4000 hours of operation, the viscosity index of comparative example 2 decreases significantly, indicating that its tackifier has poor shear resistance. The change in viscosity level will damage the lubrication performance of the oil, thereby increasing friction, wear and energy consumption, and damaging the compressor equipment. Therefore, the embodiment of the present invention has better oxidation stability and better viscosity retention ability.
[0067] (3) Better anti-wear performance: Under a load of 392 N, the wear spot diameters (WSD) of the three test balls of the embodiment of the present invention are higher than those of the comparative example 3, and the maximum no-seizure load P B The value is lower than that of Comparative Example 3, indicating that the anti-wear performance of the oil in Example 3 is better. This is because the liquid oil containing oxazoline borate undergoes a tribochemical reaction during the friction process, and a mixed film composed of B2O3, iron oxide and nitrogen-containing organic matter is formed on the surface of the wear spot, thereby playing a role in reducing friction and resisting wear.
Claims
1. A lubricating oil for a screw air compressor, characterized in that: The invention comprises the following raw materials in parts by weight: 45-58 parts by weight of PAO oil, 30-67 parts by weight of GTL oil, and 12-15.5 parts by weight of additives; The additives include: 1.2-1.5 parts by weight of antioxidant, 1-1.2 parts by weight of preservative, 1.5-2.5 parts by weight of antiwear agent, 0.3-0.4 parts by weight of rust inhibitor, and 7-15 parts by weight of viscosity index improver.
2. The lubricating oil for a screw air compressor according to claim 1, characterized in that: The PAO oil is a polyolefin synthetic base oil with a kinematic viscosity of 15-50 cst at 40° C., and the GTL oil is a GTL oil with a kinematic viscosity of 15-50 cst at 40° C.
3. The lubricating oil for a screw air compressor according to claim 1, characterized in that: The antioxidant is at least one of disulfide and butylated hydroxytoluene.
4. The lubricating oil for a screw air compressor according to claim 1, characterized in that: The preservative is at least one of thiocarbamate and benzotriazole.
5. The lubricating oil for a screw air compressor according to claim 1, characterized in that: The rust inhibitor is at least one of barium naphthenate and barium sulfonate.
6. The lubricating oil for a screw air compressor according to claim 1, characterized in that: The viscosity index improver is polymethacrylate, with a molecular weight of 20,000-100,000 and a dispersion index PDI of 1.6-2.
2.
7. The lubricating oil for a screw air compressor according to claim 1, characterized in that: The anti-wear agent is an organic borate, and the preparation method of the organic borate is: Step 1: Add tetrahydrofuran to a reaction vessel, then add 3-amino-1-phenyl-1,4-butanediol and sodium bicarbonate to the reaction vessel, add benzoyl chloride under stirring, react at 20-30° C. for 4-6 hours, remove the solvent by distillation under reduced pressure, add water, extract with dichloromethane to obtain an organic layer, dry with anhydrous magnesium sulfate, filter, and remove the solvent by distillation under reduced pressure to obtain an amide compound; Step 2: dissolve the amide compound in dichloromethane, add triethylamine and p-toluenesulfonyl chloride, react for 12-16 hours in an ice-water bath, warm to room temperature, and remove the solvent by distillation under reduced pressure to obtain an oxazoline intermediate; Step 3: Add the oxazoline intermediate, boric acid and lauryl alcohol into a reaction vessel, heat at 170-180° C. for 6-8 hours, and distill under reduced pressure to 140-160° C. after cooling to obtain oxazoline borate.
8. The lubricating oil for a screw air compressor according to claim 7, characterized in that: In the step 1, the molar ratio of 3-amino-1-phenyl-1,4-butanediol, sodium bicarbonate and benzoyl chloride is 1:(1.4-1.6):(0.9-1.1).
9. The lubricating oil for a screw air compressor according to claim 7, characterized in that: In the step 2, the molar ratio of the amide compound to p-toluenesulfonyl chloride is 1:(0.9-1.1).
10. The lubricating oil for a screw air compressor according to claim 7, characterized in that: In the step 2, the molar ratio of the reaction of the oxazoline intermediate, boric acid and lauryl alcohol is 1:(0.9-1.2):(1.8-2.2).