CN110079375B

CN110079375B - Screw compressor oil and preparation method thereof

Info

Publication number: CN110079375B
Application number: CN201910302692.8A
Authority: CN
Inventors: 赫常山; 王宜献; 蔡得华
Original assignee: Beijing Yashike Laien Petroleum Chemical Co ltd
Current assignee: Beijing Yashike Laien Petroleum Chemical Co ltd
Priority date: 2019-04-15
Filing date: 2019-04-15
Publication date: 2022-10-18
Anticipated expiration: 2039-04-15
Also published as: CN110079375A

Abstract

The invention relates to screw compressor oil and a preparation method thereof, and is characterized in that the screw compressor oil comprises a detergent, a dispersant, an antioxidant corrosion inhibitor, a wear inhibitor, an antirust agent, a demulsifier, an antifoaming agent and base oil. The base oil adopts two or three of poly-alpha-olefin (PAO), oil Soluble Polyether (OSP) and gas-to-liquids (GTL). In the invention, three different synthetic oils are adopted as the base oil in the selection of the base oil, and the screw compressor oil has the requirements of various aspects such as good thermal stability, oxidation stability, adaptability to other substances and the like while ensuring the basic requirements of lubrication and cooling, and has the service life of more than 8 thousand hours, thereby reaching the international advanced level.

Description

Screw compressor oil and preparation method thereof

Technical Field

The invention relates to the field of lubricating oil, in particular to screw compressor oil with an ultra-long service life and a preparation method thereof.

Background

The compressor is a mechanical device widely used in industry, is used for conveying gas and increasing the pressure of the gas, and is one of essential devices in production and life. The classification of the compressor has a plurality of modes, and the compressor is classified into a positive displacement type and a speed type according to different modes of compressing gas; the positive displacement compressor mainly depends on the change of working volume to realize gas compression, and the main working part is a piston or a rotor; the speed type compressor mainly changes the gas speed in the working process to change the gas kinetic energy into potential energy so as to realize the compression or the transmission of the gas, and the main working part is an impeller. Screw compressors are slaved to positive displacement compressors.

Screw compressors are classified into single screw compressors and double screw compressors, and may be classified into oil injection type and oil-free type according to the type of lubrication. The invention is used for oil injection type.

The screw compressor oil injection type lubricating system consists of a compressor main machine, an oil-gas separator, an oil cooler, a temperature control valve, the oil-gas separator and a one-way throttle valve. The power machine is mainly used in the fields of steel, electric power, metallurgy, shipbuilding, textile, electronics, chemical engineering, petroleum and natural gas, mines, light industry, mechanical manufacturing, paper-making printing, traffic facilities, food and medicine, automobile industry, aerospace, infrastructure and the like, and provides power for different tools, transportation equipment, lifting equipment and grabbing and lifting equipment.

When the screw compressor works, gas is compressed in the main machine, compressor oil is sprayed into the machine cavity in an atomized mode under the action of pressure difference, the compressor oil and a compressed medium are fully mixed in the machine cavity, and the mixture is discharged from the machine body and enters the oil-gas separator under the continuous rotation of the rotor. In the oil-gas separator, large-particle compressor oil is separated and sinks to the bottom, and gas enters a gas pipeline and is conveyed to a gas supply system through a filter. And the lubricating oil at the bottom of the separator returns to the main machine through the oil cooler and the oil filter to perform the next cycle work.

The oil sprayed into the machine cavity can play a role in cooling, lubricating, sealing, protecting and noise reduction on the screw compressor. The sprayed oil is in the form of micro-droplet fog, and after the sprayed oil is mixed with the compressed gas, the increased heat exchange surface rapidly absorbs the compression heat of the gas, cools the compression medium, and greatly reduces the exhaust temperature; the injected oil provides lubrication protection for the running male rotor, the running female rotor and the running bearing; the sprayed oil can fill various gaps, and the sealing effect is enhanced; when active gas is compressed, the compression medium can severely erode machine bodies, rotors, screws and other machine parts, and lubricating oil with good quality can adhere to the surfaces of the machine parts, so that the lubricating oil is not in direct contact with the compression medium to play a role in protection; the sprayed oil has certain absorption and damping effects on sound energy and sound waves generated in the operation process, and the noise can be reduced.

At present, in the actual operation of the screw compressor, the used compressor oil mainly adopts mineral oil, and part of the compressor oil also adopts ester synthetic oil, and the most prominent problem of the mineral oil is that the service life of the compressor oil is greatly different from that of the compressor oil with high quality internationally. Because the compressor oil is oxidized, coked, increased in viscosity and rapidly deteriorated at high temperature, the compressor oil cannot be used continuously; if ester oil is used, the acid generated after the ester oil is hydrolyzed seriously influences the quality and the service performance of the product due to the existence of moisture in the air.

In the lubricant classification standard ISO6743 established by the international organization for standardization, compressor oils are classified into two major classes, air compressor oils and gas compressor oils. In 1992 the ninth section of ISO (classification of lubricants, technical lubricants and related products (class L)) specifies compressor oils as set forth in group D; the classification is updated to GB7631.9-2014, which is the most widely used and influential classification standard in the field of compressors. In 2014, china makes detailed classification on the use of lubricants in specific fields, and provides reasonable use ranges GB7631.9 of lubricants of air compressors, lubricants of gas compressors and lubricants of refrigeration compressors; the current product standards for specific compressor oil are air compressor oil GB12691-1990, light-load oil-injection rotary compressor oil GB5904-1986 and TB/T3257-2011 air compressor oil for railway locomotives. In the product standards, only TB/T3257-2011 air compressor oil for railway locomotives is a published standard in recent years, and the air compressor oil GB12691-1990, the light-load oil injection rotary compressor oil GB5904-1986 and the standard of the 80/90 th century still cannot meet the use requirements of the existing screw compressors at all.

The service life of high-quality compressor oil reaches 8 thousand hours, and the service life of the compressor oil on the market is only more than 2 thousand hours, and the service life of the compressor oil on the market is about 4 thousand hours. In order to change the lagging phenomenon, the invention provides the screw compressor oil with the service life of more than 8 thousand hours, and the advanced level in China is reached.

Disclosure of Invention

Aiming at the defects of the prior art, the invention provides the screw compressor oil with the ultra-long service life, namely more than 8 thousand hours, and the preparation method thereof, and the prepared screw compressor oil shows excellent thermal stability, oxidation stability and high and low temperature performance by utilizing the specific composition and performance of the base oil and the good synergistic effect among various additives, is extremely suitable for the working environment of a screw compressor, and has the ultra-long service life.

A preparation method of screw compressor oil with ultra-long service life at least comprises the following steps:

adding 2/3 of the total amount of the base oil into the kettle;

adding the viscosity index improver into a kettle, heating to 65-70 ℃, and stirring for 0.5h at the temperature;

adding a detergent, a dispersant, an antioxidant corrosion inhibitor, a friction reducing agent and an antirust agent into a kettle, stirring for 1h, and mixing for 2.0h by a series-connected static mixer;

adding the residual 1/3 of the base oil into the kettle, adding the demulsifier and the antifoaming agent into the kettle, stirring and mixing for 1.0h by a stirring and static mixer, and filtering out.

The composite material comprises the following raw materials in percentage by mass: 83-89% of base oil; 2 to 3 percent of detergent; 2 to 4 percent of dispersant; viscosity index improver, 3.5%; 0.5 to 1.5 percent of antioxidant; 0.5 to 1.0 percent of antioxidant corrosion inhibitor; 0.5 to 1.5 percent of antifriction agent; 1-2% of antirust agent; demulsifier, 100ppm; antifoam, 100ppm.

According to a preferred embodiment, the base oil is prepared by a process comprising:

adding poly-alpha-olefin and oil-soluble polyether into a kettle, heating to 65-70 ℃, stirring for 0.5h at the temperature, mixing for 1.5h by a series static mixer, pumping into a measuring tank after mixing uniformly, wherein,

the content of the poly-alpha olefin is 10-90% of the mixed base oil by mass, and the content of the oil-soluble polyether is 10-90% of the mixed base oil by mass.

According to another preferred embodiment, the base oil is prepared by a process comprising:

adding poly-alpha-olefin and gas oil into a kettle, heating to 65-70 ℃, stirring for 0.5h at the temperature, mixing for 1.5h by a series static mixer, pumping into a metering tank after mixing uniformly,

the content of the poly-alpha olefin is 10-90% of the mass of the mixed base oil, and the content of the gas-making oil is 10-90% of the mass of the mixed base oil.

adding oil-soluble polyether and gas-making oil into a kettle, heating to 65-70 deg.C, stirring at the temperature for 0.5 hr, mixing with a series static mixer for 1.5 hr, mixing, adding into a measuring tank,

the content of the oil-soluble polyether is 10-90% of the mass of the mixed base oil, and the content of the gas-made oil is 10-90% of the mass of the mixed base oil.

adding poly-alpha-olefin, oil-soluble polyether and gas-made oil into a kettle, heating to 65-70 ℃, stirring for 0.5h at the temperature, mixing for 1.5h by a series static mixer, pumping into a measuring tank after mixing uniformly,

wherein the content of the polyalphaolefin is 10-80% of the mixed base oil by mass, the content of the oil-soluble polyether is 10-80% of the mixed base oil by mass, and the content of the gas-making oil is 10-80% of the mixed base oil by mass.

According to a most preferred embodiment, the base oil is prepared by:

wherein the content of the polyalphaolefin is 45% of the mass of the mixed base oil, the content of the oil-soluble polyether is 10% of the mass of the mixed base oil, and the content of the gas-making oil is 45% of the mass of the mixed base oil.

According to a preferred embodiment, the detergent employs two or three of a low base number synthetic sulfonate, a medium base number sulfonate and a medium base number sulfurized alkylphenate.

According to a preferred embodiment, the detergent is a low base number synthetic sulfonate, a medium base number sulfonate, and a medium base number sulfurized alkylphenate. The dispersant is high-activity polyisobutylene succinimide. The viscosity index improver adopts polymethacrylate. The antioxidant is mixed tert-butyl phenol. The antioxidant corrosion inhibitor adopts secondary alcohol group zinc dialkyl dithiophosphate. The friction reducing agent adopts molybdenum dialkyl dithiocarbamate and tricresyl phosphate. The rust inhibitor adopts benzene triazole octadecylamine and dodecenyl succinic acid half ester. The demulsifier adopts diamine propylene oxide polymer. The anti-foaming agent is a composite anti-foaming agent. The composite material comprises the following raw materials in percentage by mass: 86.0% of base oil; low base number synthetic sulfonate, 0.5%; medium-base sulfonate, 1.25%; medium base sulfurized alkylphenate, 0.75%; 3% of high-activity polyisobutylene succinimide; polymethacrylate, 3.5%; mixed tert-butyl phenol, 1.0%; zinc dialkyl dithiophosphate, secondary alcohol group, 0.75%; molybdenum dialkyl dithiocarbamate, 0.75%; tricresyl phosphate, 1.0%; 0.75% of phenyltriazolyl octadecylamine; dodecenyl succinic acid half ester, 0.75%; diamine propylene oxide polymer was added, 100ppm; and composite antifoaming agent is added, 100ppm. And wherein the base oil is prepared by a process comprising: adding poly alpha olefin, oil-soluble polyether and gas-made oil into a kettle, heating to 65-70 ℃, stirring for 0.5h at the temperature, mixing for 1.5h by a series static mixer, and pumping into a metering tank after mixing uniformly. Wherein the content of the polyalphaolefin is 45% of the mass of the mixed base oil, the content of the oil-soluble polyether is 10% of the mass of the mixed base oil, and the content of the gas-making oil is 45% of the mass of the mixed base oil.

The preparation method of the screw compressor oil with the ultra-long service life at least comprises the following steps: 2/3 of the total amount of the base oil is added into the kettle. Adding the viscosity index improver into a kettle, heating to 65-70 ℃, and stirring for 0.5h at the temperature. Adding the detergent, the dispersant, the antioxidant and the corrosion inhibitor, the antifriction agent and the antirust agent into a kettle, stirring for 1h, and mixing for 2.0h through a series-connected static mixer. Adding the rest 1/3 of the base oil into the kettle, adding the demulsifier and the antifoaming agent into the kettle, stirring and mixing for 1.0h by a static mixer, and filtering out.

The raw materials comprise the following components in percentage by mass: 83 to 89 percent of base oil; 2 to 3 percent of detergent; 2 to 4 percent of dispersant; viscosity index improver, 3.5%; 0.5 to 1.5 percent of antioxidant; 0.5 to 1.0 percent of antioxidant corrosion inhibitor; 0.5 to 1.5 percent of antifriction agent; 1-2% of antirust agent; demulsifier, 100ppm; antifoam, 100ppm.

According to a specific embodiment, the detergent employs low base number synthetic sulfonates, medium base number sulfonates and medium base number sulfurized alkylphenates. The dispersant is high-activity polyisobutylene succinimide. The viscosity index improver adopts polymethacrylate. The antioxidant is mixed tert-butyl phenol. The antioxidant corrosion inhibitor adopts zinc dialkyl dithiophosphate. The friction reducing agent adopts molybdenum dialkyl dithiocarbamate and tricresyl phosphate. The rust inhibitor adopts benzene triazole octadecylamine and dodecenyl succinic acid half ester. The demulsifier adopts diamine propylene oxide polymer. The anti-foaming agent is a composite anti-foaming agent. The screw compressor oil comprises the following raw materials in percentage by mass: 86.0% of base oil; low base number synthetic sulfonate, 0.5%; medium alkali sulfonate, 1.25%; medium base sulfurized alkylphenate, 0.75%; 3% of high-activity polyisobutylene succinimide; polymethacrylate, 3.5%; mixed tert-butyl phenol, 1.0%; zinc dialkyl dithiophosphate of secondary alcohol group, 0.75%; molybdenum dialkyl dithiocarbamate, 0.75%; tricresyl phosphate, 1.0%; 0.75% of phenyltriazolyl octadecylamine; dodecenyl succinic acid half ester, 0.75%; diamine propylene oxide polymer was added, 100ppm; and 100ppm of composite antifoaming agent is added. And wherein the base oil is prepared by a process comprising: adding poly-alpha-olefin, oil-soluble polyether and gas-made oil into a kettle, heating to 65-70 ℃, stirring for 0.5h at the temperature, mixing for 1.5h by a series static mixer, and pumping into a metering tank after mixing uniformly. Wherein the content of the poly-alpha-olefin is 45% of the mixed base oil by mass, the content of the oil-soluble polyether is 10% of the mixed base oil by mass, and the content of the gas-making oil is 45% of the mixed base oil by mass.

The invention has the beneficial technical effects that:

the invention adopts three synthetic oils as base oil, and gives full play to the respective advantages of the synthetic oils. The poly-alpha-olefin oil PAO has good thermal stability, high thermal decomposition temperature, high flash point and spontaneous combustion point and lower volatility, and can be used for a long time in a higher temperature environment. The oil-soluble polyether OSP has good high-temperature lubricating property, is not easy to form high-temperature and low-temperature oil sludge and carbon deposition, has good solubility, can increase the solubility of an additive in oil, has good self-lubricating property, can form a firm lubricating oil film on the surface of metal, and avoids the abrasion of the friction surface. The gas-to-liquid GTL does not contain sulfur and aromatic hydrocarbon, has good oxidation stability and high biodegradation rate, is an environment-friendly product, has high viscosity index, good viscosity-temperature performance and wide use temperature range, and can adapt to different use working conditions. The gas oil adopted by the invention has the same quality as synthetic oil in the characteristics of high and low temperature performance, shearing resistance, oxidation stability, lubricating performance and the like, but has much lower price than the synthetic oil and high cost performance.

The selected detergent dispersant is selected according to the working characteristics of the screw compressor. Considering that the detergency required by the screw compressor is higher than the neutrality, three detergents are selected to be combined with low-base-number synthetic calcium sulfonate, medium-base-number synthetic sulfonate and medium-base-number sulfurized calcium alkyl phenate, so that the cleaning effect is emphasized, and the acidic substances generated in the working process of the screw compressor are neutralized, so that the effectiveness of the lubricating performance of the lubricating oil is ensured.

The screw compressor oil disclosed by the invention is good in lubricating property, stable in thermal stability and oxidation stability, slow in viscosity increase after long-time use at high temperature, remarkably prolonged in service life, long in oil change period and remarkably reduced in use cost, and the service life of the screw compressor oil can reach more than 8 thousand hours.

Detailed Description

The following detailed description is given in conjunction with preferred embodiments of the present invention. It should be noted that the embodiments described herein do not limit the scope of the invention thereby. Any alterations and further modifications of the inventive features illustrated herein, and any additional applications of the principles of the invention as illustrated herein, which would normally occur to one skilled in the relevant art, are contemplated as within the scope of the invention.

The invention discloses a preparation method of screw compressor oil with ultra-long service life, which at least comprises the following raw materials: detergent, dispersant, viscosity index improver, antioxidant, anticorrosive agent, antiwear agent, preservative, antirust agent, demulsifier and defoaming agent. The raw materials comprise the following components in percentage by mass: 83-89% of base oil; 2 to 3 percent of detergent; 2 to 4 percent of dispersant; viscosity index improver, 3.5%; 0.5 to 1.5 percent of antioxidant; 0.5 to 1.0 percent of antioxidant corrosion inhibitor; 0.5 to 1.5 percent of antifriction agent; 1-2% of antirust agent; demulsifier, 100ppm; antifoam, 100ppm.

The preparation method at least comprises the following steps:

2/3 of the total amount of the base oil is added into the kettle;

Preferably, the detergent used in the screw compressor oil of the present invention is at least one of a low-base number synthetic sulfonate, a medium-base number sulfonate, and a medium-base number sulfurized alkylphenate. The addition amount of the cleaning agent is 2-3% of the total mass of the screw compressor oil. The detergent dispersant used in the present invention is selected according to the working characteristics of the screw compressor. Considering that the detergency required by the screw compressor is greater than the neutrality, three detergents are selected to be combined and used by low-base-number synthetic calcium sulfonate, medium-base-number synthetic calcium sulfonate and medium-base-number sulfurized calcium alkyl phenate, so that the washing effect is emphasized, and the neutralization of acidic substances generated in the working process of the screw compressor is also considered, so that the effectiveness of the lubricating performance of the lubricating oil is ensured.

More preferably, the detergent raw material consists of: 20% low base number synthetic sulfonate, 50% medium base number sulfonate and 30% medium base number sulfurized alkylphenate.

Table 1 lists the technical indices for low base number synthesis of calcium sulfonate. The technical indexes of the medium-base-number synthesized calcium sulfonate are listed in the table 2. The technical indexes of the medium-alkali sulfurized calcium alkyl phenate are shown in Table 3.

TABLE 1 technical index for low base number synthetic calcium sulfonate

Item	Quality index	Test method
			Appearance of the product	Reddish brown viscous liquid	Visual inspection of
Density (20 ℃ C.) kg/m ³	900～1000	GB/T13377
			Kinematic viscosity (100 ℃ C.) mm ² /s≯	30	GB/T265
Flash point (opening) at not less than DEG C	180	GB/T3536
			Total base number mgKOH/g	20～35	SH/T0251
Higher than or equal to m% of calcium content	2.0	GB/T17476
			Not rich in sulfur content m%	2.0	ASTM D1552

Technical index of calcium sulfonate base number in Table 2

Item	Quality index	Test method
			Appearance of the product	Reddish brown viscous liquid	Visual inspection of
Density (20 ℃ C.) kg/m ³	1000～1050	GB/T13377
			Kinematic viscosity (100 ℃ C.) mm ² /s≯	20～50	GB/T265
Flash point (opening) at not less than DEG C	180	GB/T3536
			Total base number mgKOH/g	145	SH/T0251
Higher than or equal to m% of calcium content	6.5	GB/T17476
			Higher or lower than m% of sulfur content	1.8～2.2	ASTM D1552

Alkali sulfurized calcium alkyl phenolate technical index in Table 3

Item	Quality index	Test method
			Density (20 ℃ C.) kg/m ³	980～1050	GB/T13377
Kinematic viscosity (100 ℃ C.) mm ² /s≯	30～40	GB/T265
			Flash point (opening) at not less than DEG C	170	GB/T3536
Total base number mgKOH/g	150～170	SH/T0251
			Higher than or equal to m% of calcium content	5.2～6.0	GB/T17476
Higher or lower than m% of sulfur content	2.3～2.8	ASTM D1552

Preferably, the dispersant used in the screw compressor oil of the present invention is a highly active polyisobutylene succinimide. The addition amount of the dispersing agent is 2-4% of the total mass of the screw compressor oil. Highly reactive polyisobutylene succinimide was prepared using highly reactive polyisobutylene (Mn = 1000). The polyisobutylene succinimide is an ashless dispersant, has good cleaning dispersity, and can inhibit carbon deposit on an engine piston and the generation of a paint film. Table 4 shows the technical specifications of the highly reactive polyisobutylene succinimide

TABLE 4 technical indices of highly reactive polyisobutylene succinimide

Item	Quality index	Test method
			Appearance of the product	Viscous transparent liquid	Visual inspection of
Kinematic viscosity (100 ℃ C.) mm ² /s≯	130～230	GB/T265
			Flash point (opening) at not less than DEG C	180	GB/T3536
Total base number mgKOH/g	15～30	SH/T0251
			No higher or lower nitrogen content than m%	1.1～1.5	GB/T17476

Preferably, the viscosity index improver used in the screw compressor oil of the present invention is polymethacrylate. The addition amount of the viscosity index improver is 3.5 percent of the total mass of the screw compressor oil.

Preferably, the antioxidant used in the screw compressor oil of the present invention is a mixed tert-butylphenol. The addition amount of the antioxidant is 0.5-1.5% of the total mass of the screw compressor oil. Wherein the mixed tert-butylphenol comprises 2, 6-di-tert-butylphenol, o-tert-butylphenol, tri-tert-butylphenol and alkylphenol.

Preferably, the antioxidant and corrosion inhibitor used in the screw compressor oil of the present invention is zinc dialkyl dithiophosphate. The addition amount of the oxidation and corrosion inhibitor is 0.5 to 1.0 percent of the total mass of the screw compressor oil. The secondary alcohol-based zinc dialkyl dithiophosphate is also a multi-effect additive with an antifriction effect. The zinc dialkyl dithiophosphate is a product synthesized by adopting different alkyls, has high thermal decomposition temperature, good oil solubility and excellent oxidation resistance, also has excellent antifriction performance, and can effectively reduce the mechanical wear. The specifications for the secondary alcohol ZDDPs are shown in Table 5.

TABLE 5 Secondary alcoholic ZDDP technical index

Item	Quality index	Test method
			Appearance of the product	Amber colored transparent liquid	Visual inspection of
Kinematic viscosity (100 ℃) mm2/s not more	Report(s)	GB/T265
			Flash point (opening) at not less than DEG C	180	GB/T3536
Density (20 ℃ C.) kg/m3	1050～1150	GB/T13377
			The sulfur content is m%	13.5～18.0	GB/T17476
The phosphorus content is m%	6.5～9.0	GB/T17476
			The content of zinc is m%	8.0～11.0	GB/T17476
pH≮	5.5	SH/T0394-96 appendix A

Preferably, the wear reducing agents used in the screw compressor oil of the present invention are molybdenum dialkyldithiocarbamate and tricresyl phosphate. The addition amount of the molybdenum dialkyl dithiocarbamate is 0.5 to 1.0 percent of the total mass of the screw compressor oil. The addition amount of the tricresyl phosphate is 0.5-1.5% of the total mass of the screw compressor oil. The molybdenum dialkyl dithiocarbamate has good wear resistance, can greatly reduce the friction coefficient, and can reduce the wear under the condition of boundary lubrication. The tricresyl phosphate has certain extreme pressure resistance, and can improve the working capacity of a lubricating medium under the working condition of high load. The specifications for molybdenum dialkyldithiocarbamates are listed in table 6. Technical indices of tricresyl phosphate are listed in table 7.

TABLE 6 molybdenum dialkyldithiocarbamates technical index

Item	Quality index	Test method
			Appearance of the product	Brown liquid	Visual inspection of
No less than or equal to mm2 in kinematic viscosity (100 ℃ C.)	11.5	GB/T265
			Flash point (opening) at not less than DEG C	180	GB/T3536
No higher or lower nitrogen content than m%	0.45～0.65	GB/T17476
			Molybdenum content m% > (not less than)	5.5～6.5	GB/T17476

TABLE 7 technical index for tricresyl phosphate

Item	Quality index	Test method
			Density, 20 ℃, kg/m ³ ≯	1190	GB/T1884
Not less than% free cresol	0.2	Q/SY206009
			Flash point (opening) at not less than DEG C	220	GB/T267
The acid value of mgKOH/g is not more than	0.25	GB/T264

Preferably, the rust inhibitor used by the screw compressor oil is benzene triazole octadecylamine and dodecenyl succinic acid half ester. The addition amount of the phenyltriazole octadecylamine is 0.5-1.0% of the total mass of the screw compressor oil. The addition amount of the dodecenyl succinic acid half ester is 0.5 to 1.0 percent of the total mass of the screw compressor oil.

Preferably, the demulsifier used in the screw compressor oil of the present invention is a diamine propylene oxide polymer. The amount of demulsifier added was 100ppm (addition).

Preferably, the antifoaming agent used in the screw compressor oil of the present invention is a composite antifoaming agent. The amount of the antifoaming agent added was 100ppm (added).

The high and low temperature performance, thermal stability, oxidation stability and lubricity of the screw compressor oil are completely determined by the base oil. Thus, the most important properties of the base oil for the preparation of screw compressor oils are viscosity, thermal stability, oxidation stability, evaporation, viscosity-temperature characteristics, freezing point and lubricating ability.

According to a preferred embodiment, the base oil used in the screw compressor oil of the present invention is a synthetic hydrocarbon oil having various characteristics, polyalphaolefin, oil-soluble polyether and gas oil. Compared with common mineral oil, the poly-alpha-olefin has the advantages of good thermal stability, high thermal decomposition temperature, high flash point and spontaneous combustion point, lower volatility, higher use temperature and the like. The oil-soluble polyether has good high-temperature performance, can form small molecules during oxidative decomposition, is not easy to form high-temperature and low-temperature oil sludge and carbon deposition, has good solubility, increases the solubility of the additive in oil, has good lubricating performance, can form a firm lubricating oil film on the surface of metal, and avoids the abrasion of the friction surface. The gas-to-liquid oil contains no sulfur and aromatic hydrocarbon, has high viscosity index, good oxidation stability, good thermal stability and chemical stability, no coking at high temperature and excellent cleaning performance. The oil-soluble polyether has excellent antifriction performance and the capability of controlling carbon deposition and oil sludge generation, and can reduce the exhaust temperature.

Preferably, the mixed base oil adopts the mixed base oil containing the polyalphaolefin and the oil-soluble polyether. Wherein, the content of the poly-alpha olefin is 10 to 90 percent of the mass of the mixed base oil, and the content of the oil-soluble polyether is 10 to 90 percent of the mass of the mixed base oil.

Preferably, the base oil is prepared by the following steps: adding poly-alpha-olefin and oil-soluble polyether into a kettle, heating to 65-70 ℃, stirring for 0.5h at the temperature, mixing for 1.5h through a series static mixer, and pumping into a metering tank after mixing uniformly. Wherein, the content of the poly-alpha olefin is 10 to 90 percent of the mass of the mixed base oil, and the content of the oil-soluble polyether is 10 to 90 percent of the mass of the mixed base oil.

Preferably, the mixed base oil is a mixed base oil containing both base oils of polyalphaolefin and gas oil. Wherein the content of the poly-alpha olefin is 10-90% of the mass of the mixed base oil, and the content of the gas-to-liquid is 10-90% of the mass of the mixed base oil.

Preferably, the base oil is prepared by the following steps: adding poly-alpha-olefin and gas oil into a kettle, heating to 65-70 ℃, stirring for 0.5h at the temperature, mixing for 1.5h by a series static mixer, and pumping into a metering tank after mixing uniformly. Wherein the content of the poly-alpha olefin is 10-90% of the mass of the mixed base oil, and the content of the gas-to-liquid is 10-90% of the mass of the mixed base oil.

Preferably, the mixed base oil is a mixed base oil containing oil-soluble polyether and gas oil. Wherein, the content of the oil-soluble polyether is 10-90% of the mass of the mixed base oil, and the content of the gas-made oil is 10-90% of the mass of the mixed base oil.

Preferably, the base oil is prepared by the following steps: adding oil-soluble polyether and gas-making oil into a kettle, heating to 65-70 ℃, stirring for 0.5h at the temperature, mixing for 1.5h by a series-connected static mixer, and pumping into a metering tank after mixing uniformly. Wherein, the content of the oil-soluble polyether is 10-90% of the mass of the mixed base oil, and the content of the gas-made oil is 10-90% of the mass of the mixed base oil.

Preferably, the mixed base oil is a mixed base oil containing three base oils of poly-alpha-olefin, oil-soluble polyether and gas oil. Wherein the content of the poly-alpha-olefin accounts for 10-80% of the mass of the mixed base oil, the content of the oil-soluble polyether accounts for 10-80% of the mass of the mixed base oil, and the content of the gas oil accounts for 10-80% of the mass of the mixed base oil.

Preferably, the base oil is prepared by the following steps: adding poly alpha olefin, oil-soluble polyether and gas-made oil into a kettle, heating to 65-70 ℃, stirring for 0.5h at the temperature, mixing for 1.5h by a series static mixer, and pumping into a metering tank after mixing uniformly. Wherein, the content of the poly-alpha olefin is 10 to 80 percent of the mass of the mixed base oil, the content of the oil-soluble polyether is 10 to 80 percent of the mass of the mixed base oil, and the content of the gas-making oil is 10 to 80 percent of the mass of the mixed base oil.

In a most preferred embodiment, the base oil is prepared by a process comprising: adding poly alpha olefin, oil-soluble polyether and gas-made oil into a kettle, heating to 65-70 ℃, stirring for 0.5h at the temperature, mixing for 1.5h by a series static mixer, and pumping into a metering tank after mixing uniformly. Wherein the content of the polyalphaolefin is 45% of the mass of the mixed base oil, the content of the oil-soluble polyether is 10% of the mass of the mixed base oil, and the content of the gas oil is 45% of the mass of the mixed base oil.

According to a preferred embodiment, the detergent is a low base number synthetic sulfonate, a medium base number sulfonate, and a medium base number sulfurized alkylphenate. The dispersant is high-activity polyisobutylene succinimide. The viscosity index improver adopts polymethacrylate. The antioxidant is mixed tert-butyl phenol. The antioxidant corrosion inhibitor adopts secondary alcohol group zinc dialkyl dithiophosphate. The friction reducing agent adopts molybdenum dialkyl dithiocarbamate and tricresyl phosphate. The rust inhibitor adopts benzene triazole octadecylamine and dodecenyl succinic acid half ester. The demulsifier adopts diamine propylene oxide polymer. The anti-foaming agent is a composite anti-foaming agent. The composite material comprises the following raw materials in percentage by mass: 86.0% of base oil; low base number synthetic sulfonate, 0.5%; medium-base sulfonate, 1.25%; medium base sulfurized alkylphenate, 0.75%; 3% of high-activity polyisobutylene succinimide; polymethacrylate, 3.5%; mixed tert-butyl phenol, 1.0%; zinc dialkyl dithiophosphate, secondary alcohol group, 0.75%; molybdenum dialkyldithiocarbamate, 0.75%; tricresyl phosphate, 1.0%; 0.75% of phenyltriazolyl octadecylamine; dodecenyl succinic acid half ester, 0.75%; diamine propylene oxide polymer was added, 100ppm; and 100ppm of composite antifoaming agent is added. And wherein the base oil is prepared by the following steps: adding poly alpha olefin, oil-soluble polyether and gas-made oil into a kettle, heating to 65-70 ℃, stirring for 0.5h at the temperature, mixing for 1.5h by a series static mixer, and pumping into a metering tank after mixing uniformly. Wherein the content of the polyalphaolefin is 45% of the mass of the mixed base oil, the content of the oil-soluble polyether is 10% of the mass of the mixed base oil, and the content of the gas-making oil is 45% of the mass of the mixed base oil.

The specifications of the preferred base oil components of the present invention, i.e., polyalphaolefin, oil-soluble polyether and gas oil, are listed in table 8. Table 9 lists the technical specifications of the blended base oil of a preferred embodiment of the screw compressor oil of the present invention, in which the blended base oil is prepared by the following method: adding poly alpha olefin, oil-soluble polyether and gas-made oil into a kettle, heating to 65-70 ℃, stirring for 0.5h at the temperature, mixing for 1.5h by a series static mixer, and pumping into a metering tank after mixing uniformly. Wherein the content of the poly-alpha-olefin is 45% of the mixed base oil by mass, the content of the oil-soluble polyether is 10% of the mixed base oil by mass, and the content of the gas-making oil is 45% of the mixed base oil by mass.

TABLE 8 preferred base oil specifications

Item	PAO 10	Polyether (OSP 68)	Gas-to-liquid oil
				Appearance of the product	Colorless and transparent	Colorless and transparent	Colorless and transparent
Kinematic viscosity (mm) at 40 ℃ ² /s)	65.68	46.10	43.68
				Kinematic viscosity (mm) at 100 ℃ ² /s)	9.68	6.96	7.68
Viscosity index	132	110	146
				Pour point C	-48	-23	-38
Flash point (open)	263	230	228
				Acid value mgKOH/g	＜0.05	＜0.1	＜0.1

TABLE 9 preferred blend base oil specifications

According to a specific embodiment of the invention, the screw compressor oil comprises the following components in percentage by weight: 0.4 to 0.6 percent of low-base-number synthetic calcium sulfonate, 1.0 to 1.5 percent of medium-base-number calcium sulfonate, 0.6 to 0.9 percent of medium-base-number sulfurized calcium alkyl phenate, 2.0 to 4.0 percent of high-molecular-weight polyisobutylene succinimide, 3.5 percent of polymethacrylate, 0.5 to 1.5 percent of mixed tert-butyl phenol, 0.5 to 1.0 percent of zinc dialkyl dithiophosphate, 0.5 to 1.0 percent of molybdenum dialkyl dithiocarbamate, 0.5 to 1.5 percent of trimethyl phosphate, 0.5 to 1.0 percent of benzotriazole octadecylamine, 0.5 to 1.0 percent of dodecenyl succinic acid half ester, 83.0 to 89.0 percent of base oil, 100ppm of diamine propylene oxide polymer (added), and 100ppm of composite antifoaming agent (added). The sum of the weight percentages of the components is 100 percent.

Examples

The features and advantages of the screw compressor oil of the present invention will be described in detail below according to 3 specific examples of the present invention, which are example 1, example 2 and example 3, respectively. The percentage composition of the raw materials for examples 1-3 is listed in table 10.

Table 10 percentage composition table of raw materials of examples 1 to 3

The respective preparation methods of the screw compressor oil of the present invention of examples 1 to 3 were respectively:

example 1

Adding 45% of poly-alpha-olefin, 10% of oil-soluble polyether and 45% of gas-to-liquid into a kettle, heating to 65-70 ℃, stirring for 0.5h, mixing for 1.5h through a series static mixer, and pumping into a metering tank for later use after uniform mixing;

adding 89kg of 2/3 mixed base oil into a kettle, adding 3.5% of polymethacrylate, heating to 65-70 ℃, stirring for 0.5h, adding 0.4% of low-base-number synthetic calcium sulfonate, 1.0% of medium-base-number calcium sulfonate, 0.6% of sulfurized calcium alkylphenol, 2% of high-activity polyisobutylene succinimide, 0.5% of mixed tert-butylphenol, 0.5% of secondary alcohol dialkyl zinc dialkyl dithiophosphate, 0.5% of dialkyl molybdenum dithiocarbamate, 0.5% of tricresyl phosphate, 0.5% of benzotriazole octadecylamine, 1.0% of dodecenyl succinic acid half ester, stirring for 1h, mixing for 2.0h through a series static mixer, adding the rest 1/3 mixed base oil, adding 100ppm of diamine propylene oxide polymer (additionally added) and 100ppm of composite antifoaming agent (additionally added), stirring and mixing for 1.0h through the static mixer, and filtering.

Example 2

Adding 45% of poly-alpha-olefin, 10% of oil-soluble polyether and 45% of gas-to-liquid into a kettle, heating to 65-70 ℃, stirring for 0.5h, mixing for 1.5h through a series static mixer, and pumping into a metering tank after mixing uniformly;

adding 86.0kg of 2/3 mixed base oil into a kettle, adding 3.5% of polymethacrylate, heating to 65-70 ℃, stirring for 0.5h, adding 0.5% of low-base-number synthetic calcium sulfonate, 1.25% of medium-base-number calcium sulfonate, 0.75% of sulfurized calcium alkyl phenol, 3% of high-activity polyisobutylene succinimide, 1.0% of mixed tert-butyl phenol, 0.75% of secondary alcohol-based dialkyl zinc dithiophosphate, 0.75% of dialkyl molybdenum dithiocarbamate, 1.0% of tricresyl phosphate, 0.75% of benzotriazole octadecylamine, and 0.75% of dodecenyl succinic acid half ester, stirring for 1h, mixing for 2.0h through a serial static mixer, adding the rest 1/3 mixed base oil, adding 100ppm of diamine propylene oxide polymer (additionally added), 100ppm of composite antifoaming agent (additionally added), and stirring and mixing for 1.0h through the static mixer.

Example 3

adding 83.0kg of 2/3 mixed base oil into a kettle, adding 3.5% of polymethacrylate, heating to 65-70 ℃, stirring for 0.5h, adding 0.6% of low-base-number synthetic calcium sulfonate, 1.5% of medium-base-number calcium sulfonate, 0.9% of sulfurized calcium alkyl phenolate, 4% of high-activity polyisobutylene succinimide, 1.5% of mixed tert-butylphenol, 1.0% of secondary hydroxyl dialkyl zinc dithiophosphate, 1.5% of molybdenum dialkyl dithiocarbamate, 3.0% of tricresyl phosphate, 1.0% of benzotriazole octadecylamine, 0.5% of dodecenylsuccinic acid half-ester, stirring for 1h, mixing for 2.0h by a series static mixer, adding the rest 1/3 mixed base oil, adding 100ppm of diamine propylene oxide polymer (additionally added) and 100ppm of composite antifoaming agent (additionally added), and stirring and mixing for 1.0h by a stirring static mixer.

Comparative example

A commercially available screw compressor oil product having a service life of 8000 hours was used as a comparative example. The product specifications of examples 1 to 3 and comparative example are listed in table 11.

TABLE 11 technical indices of products of examples 1 to 3 and comparative example

Comparing each performance data of the embodiment and the comparative example, the kinematic viscosity of the embodiment of the invention is equivalent to that of the comparative example, the viscosity index is obviously improved, the pour point is lower, the flash point is higher, the oxidation stability is obviously improved, and the increment of residual carbon is obviously reduced. On the key indexes influencing the service life of the screw compressor oil, particularly high and low temperature viscosity, oxidation stability and carbon residue increment, the embodiment of the invention is obviously improved compared with a comparative example with 8000-hour service life. Therefore, the screw compressor oil has the service life of more than 8000 hours, especially more than 10000 hours, and the performance is obviously improved.

The performance improvement and the service life extension of the screw compressor oil are realized by three creative technical means, namely: the selection of base oil and raw material composition, the selection of additive and raw material composition and the corresponding preparation method of base oil and screw compressor oil.

Specifically, the invention adopts three synthetic oils as base oil, and gives full play to the respective advantages of the synthetic oils. The poly-alpha-olefin oil PAO has good thermal stability, high thermal decomposition temperature, high flash point and self-ignition point and low volatility, and can be used for a long time in a high-temperature environment. The oil-soluble polyether OSP has good high-temperature lubricating property, is not easy to form high-temperature and low-temperature oil sludge and carbon deposition, has good solubility, can increase the solubility of an additive in oil, has good self-lubricating property, can form a firm lubricating oil film on the surface of metal, and avoids the abrasion of the friction surface. The gas-to-liquid GTL does not contain sulfur and aromatic hydrocarbon, has good oxidation stability and high biodegradation rate, is an environment-friendly product, has high viscosity index, good viscosity-temperature performance and wide use temperature range, and can adapt to different use working conditions. The gas oil adopted by the invention has the same quality as synthetic oil in the characteristics of high and low temperature performance, shearing resistance, oxidation stability, lubricating performance and the like, but has much lower price than the synthetic oil and high cost performance. The mixed base oil prepared by adopting the three synthetic oils according to a specific proportion fully exerts respective advantages through the synergistic effect of the three synthetic oils, avoids the defects existing in single use to the maximum extent, and obtains the mixed base oil with obviously improved aspects of heat stability, oxidation stability, carbon deposition, lubricity and the like.

In addition, the invention also selects specific additives and corresponding specific proportions according to the working characteristics of the screw compressor. Considering that the detergency required by the screw compressor is higher than the neutrality, three detergents are selected to be combined with low-base-number synthetic calcium sulfonate, medium-base-number synthetic sulfonate and medium-base-number sulfurized calcium alkyl phenate, so that the cleaning effect is emphasized, and the acidic substances generated in the working process of the screw compressor are neutralized, so that the effectiveness of the lubricating performance of the lubricating oil is ensured. The detergent adopts at least one of low-base-number synthetic sulfonate, medium-base-number sulfonate and medium-base-number sulfurized alkylphenate, and the addition amount of the detergent is 2-3% of the total mass of the screw compressor oil. The dispersant is high-activity polyisobutylene succinimide, and the addition amount of the dispersant is 2-4% of the total mass of the screw compressor oil. The viscosity index improver is polymethacrylate, and the addition amount of the viscosity index improver is 3.5 percent of the total mass of the screw compressor oil. The antioxidant is mixed tert-butyl phenol, and the addition amount of the antioxidant is 0.5-1.5% of the total mass of the screw compressor oil, wherein the mixed tert-butyl phenol contains 2, 6-di-tert-butyl phenol, o-tert-butyl phenol, tri-tert-butyl phenol and alkylphenol. The antioxidant corrosion inhibitor is zinc dialkyl dithiophosphate, and the addition amount of the antioxidant corrosion inhibitor is 0.5 to 1.0 percent of the total mass of the screw compressor oil. The antifriction agent is molybdenum dialkyl dithiocarbamate and tricresyl phosphate, wherein the addition amount of the molybdenum dialkyl dithiocarbamate is 0.5-1.0% of the total mass of the screw compressor oil, and the addition amount of the tricresyl phosphate is 0.5-1.5% of the total mass of the screw compressor oil. The antirust agent is phenyltriazole octadecylamine and dodecenyl succinic acid half-ester, wherein the addition amount of the phenyltriazole octadecylamine is 0.5-1.0% of the total mass of the screw compressor oil, and the addition amount of the dodecenyl succinic acid half-ester is 0.5-1.0% of the total mass of the screw compressor oil. The demulsifier is diamine propylene oxide polymer, and the addition amount is 100ppm (additionally). The antifoaming agent is a composite antifoaming agent, and the addition amount is 100ppm (added). Through the synergistic effect of the specific additives in a specific proportion, the performances of the screw compressor oil are obviously improved, so that the service life of the screw compressor oil is finally obviously prolonged to more than 8 thousand hours.

Besides the selection and the proportion of the base oil and the additive, the preparation method of the screw compressor oil disclosed by the invention also plays a key role in the performance of the screw compressor oil. The preparation method at least comprises the following steps: adding 2/3 of the total amount of the base oil into the kettle; adding the viscosity index improver into a kettle, heating to 65-70 ℃, and stirring for 0.5h at the temperature; adding a detergent, a dispersant, an antioxidant corrosion inhibitor, a friction reducing agent and an antirust agent into a kettle, stirring for 1h, and mixing for 2.0h by a series-connected static mixer; adding the rest 1/3 of the base oil into the kettle, adding the demulsifier and the antifoaming agent into the kettle, stirring and mixing for 1.0h by a static mixer, and filtering out. The preparation method of the base oil comprises the following steps: adding poly alpha olefin, oil-soluble polyether and gas-made oil into a kettle, heating to 65-70 ℃, stirring for 0.5h at the temperature, mixing for 1.5h by a series static mixer, and pumping into a metering tank after mixing uniformly.

In the preparation method, the details of the preparation method of the base oil include temperature, stirring time, and standing time; the details of the preparation method of the screw compressor oil comprise that the mixed base oil is added for 2/3 and 1/3 twice, the addition sequence of the additives, the mixing and stirring temperature, the stirring time, the standing time and the like have obvious influence on the performance and the actual application condition of whether the screw compressor oil and the final screw compressor oil finished product can be successfully obtained, and the performance of the final product can be obviously reduced by slight difference or change of the preparation method, even the finished product meeting the application requirement can not be obtained. All the technical details are not common knowledge, and can not be obtained by common general knowledge or limited experiments of technicians in the field, so that the screw compressor oil and the preparation method thereof have substantial progress, solve the technical problems which need to be solved but not solved for a long time in the field, obtain obviously improved technical effects by means of non-common knowledge or common technical methods in the field, and meet the creative requirements.

According to the test results in table 11, the raw material ratio of example 2 is the most preferable embodiment.

The screw compressor oil of example 2 was tested in a screw air compressor model SCREWAIRCOMPRESOR. The double-shaft positive displacement rotary compressor has air inlet in the upper end, air outlet in the lower part, exhaust temperature of 70-90 deg.c, exhaust pressure of 0.75MPa and exhaust amount of 30m ³ Min, belonging to the medium-sized air compressor. The screw compressor oil of example 2 was actually used for 10000 hours. Table 12 shows the specifications of the most preferred embodiment of the present invention, example 2, after 10000 hours of actual operation

TABLE 12 technical index of example 2 after 10000 hours of actual operation

As shown in the table above, in example 2, after 10000 hours of actual operation, all the indexes are within the ideal index range, meet the use requirements of the screw compressor, and can be continuously used without replacement, so that the service life of the screw compressor is 8000 hours, especially more than 10000 hours.

Therefore, according to the technical indexes of the screw compressor oil of the above examples and the comparison thereof with the comparative example, and the technical indexes of the preferred examples after 10000 hours of actual operation, the present invention provides a screw compressor oil having a service life of more than 8 kilohours. Compared with the existing screw compressor oil with the service life of only 2000-4000 hours in the market, the screw compressor oil provided by the invention has the advantages that the service life is obviously prolonged, the oil change period is prolonged, and the use cost is reduced.

The invention also discloses screw compressor oil with an ultra-long service life, and the preparation method at least comprises the following steps: 2/3 of the total amount of the base oil is added into the kettle. Adding the viscosity index improver into a kettle, heating to 65-70 ℃, and stirring for 0.5h at the temperature. Adding the detergent, the dispersant, the antioxidant and the corrosion inhibitor, the antifriction agent and the antirust agent into a kettle, stirring for 1h, and mixing for 2.0h through a series-connected static mixer. Adding the residual 1/3 of the base oil into the kettle, adding the demulsifier and the antifoaming agent into the kettle, stirring and mixing for 1.0h by a stirring and static mixer, and filtering out.

The material composition is as follows by mass percent: 83-89% of base oil; 2 to 3 percent of detergent; 2 to 4 percent of dispersant; viscosity index improver, 3.5%; 0.5 to 1.5 percent of antioxidant; 0.5 to 1.0 percent of antioxidant corrosion inhibitor; 0.5 to 1.5 percent of antifriction agent; 1-2% of antirust agent; demulsifier, 100ppm; antifoam, 100ppm.

Preferably, the base oil is a mixed base oil containing two base oils of poly-alpha-olefin and oil-soluble polyether. Wherein, the content of the poly-alpha olefin is 10 to 90 percent of the mass of the mixed base oil, and the content of the oil-soluble polyether is 10 to 90 percent of the mass of the mixed base oil.

Preferably, the base oil is a mixed base oil containing two base oils of polyalphaolefin and gas oil. Wherein the content of the poly-alpha olefin is 10-90% of the mass of the mixed base oil, and the content of the gas-to-liquid is 10-90% of the mass of the mixed base oil.

Preferably, the base oil is a mixed base oil containing oil-soluble polyether and gas oil. Wherein, the content of the oil-soluble polyether is 10-90% of the mass of the mixed base oil, and the content of the gas-made oil is 10-90% of the mass of the mixed base oil.

Preferably, the base oil is a mixed base oil containing three base oils of poly-alpha-olefin, oil-soluble polyether and gas oil. Wherein the content of the polyalphaolefin is 10-80% of the mass of the mixed base oil, the content of the oil-soluble polyether is 10-80% of the mass of the mixed base oil, and the content of the gas oil is 10-80% of the mass of the mixed base oil.

Preferably, the base oil is a mixed base oil containing three base oils of poly-alpha-olefin, oil-soluble polyether and gas oil. Wherein the content of the polyalphaolefin is 45% by mass of the mixed base oil, the content of the oil-soluble polyether is 10% by mass of the mixed base oil, and the content of the gas oil is 45% by mass of the mixed base oil.

Preferably, the cleaning agent used in the screw compressor oil of the present invention is at least one of a low base number synthetic sulfonate, a medium base number sulfonate, and a medium base number sulfurized alkylphenate. The addition amount of the cleaning agent is 2-3% of the total mass of the screw compressor oil.

Preferably, the dispersant used in the screw compressor oil of the present invention is a highly active polyisobutylene succinimide. The addition amount of the dispersing agent is 2-4% of the total mass of the screw compressor oil.

Preferably, the antioxidant and corrosion inhibitor used in the screw compressor oil of the present invention is zinc dialkyl dithiophosphate. The addition amount of the oxidation and corrosion inhibitor is 0.5 to 1.0 percent of the total mass of the screw compressor oil.

Preferably, the wear reducing agents used in the screw compressor oil of the present invention are molybdenum dialkyldithiocarbamate and tricresyl phosphate. The addition amount of the molybdenum dialkyl dithiocarbamate is 0.5 to 1.0 percent of the total mass of the screw compressor oil. The addition amount of the tricresyl phosphate is 0.5-1.5% of the total mass of the screw compressor oil.

Preferably, the antifoaming agent used in the screw compressor oil of the present invention is a complex antifoaming agent. The amount of the antifoaming agent added was 100ppm (added).

According to a preferred embodiment, the detergent employs low base number synthetic sulfonates, medium base number sulfonates and medium base number sulfurized alkylphenates. The dispersant is high-activity polyisobutylene succinimide. The viscosity index improver adopts polymethacrylate. The antioxidant is mixed tert-butyl phenol. The antioxidant corrosion inhibitor adopts secondary alcohol group zinc dialkyl dithiophosphate. The antifriction agent adopts molybdenum dialkyl dithiocarbamate and tricresyl phosphate. The rust inhibitor adopts benzene triazole octadecylamine and dodecenyl succinic acid half ester. The demulsifier adopts diamine propylene oxide polymer. The anti-foaming agent is a composite anti-foaming agent. The screw compressor oil comprises the following raw materials in percentage by mass: base oil, 86.0%; low base number synthetic sulfonate, 0.5%; medium-base sulfonate, 1.25%; medium base sulfurized alkylphenate, 0.75%; 3% of high-activity polyisobutylene succinimide; polymethacrylate, 3.5%; mixed tert-butyl phenol, 1.0%; zinc dialkyl dithiophosphate of secondary alcohol group, 0.75%; molybdenum dialkyl dithiocarbamate, 0.75%; tricresyl phosphate, 1.0%; 0.75% of benzotriazole octadecylamine; dodecenyl succinic acid half ester, 0.75%; diamine propylene oxide polymer was added, 100ppm; and 100ppm of composite antifoaming agent is added. And wherein the base oil is prepared by a process comprising: adding poly alpha olefin, oil-soluble polyether and gas-made oil into a kettle, heating to 65-70 ℃, stirring for 0.5h at the temperature, mixing for 1.5h by a series static mixer, and pumping into a metering tank after mixing uniformly. Wherein the content of the polyalphaolefin is 45% of the mass of the mixed base oil, the content of the oil-soluble polyether is 10% of the mass of the mixed base oil, and the content of the gas-making oil is 45% of the mass of the mixed base oil.

It should be noted that the above-mentioned embodiments are exemplary, and that those skilled in the art, having benefit of this disclosure, may devise various solutions which are within the scope of this disclosure and are within the scope of the invention. It is to be understood by persons skilled in the art that the present description is illustrative only and not limiting upon the claims. The scope of the invention is defined by the claims and their equivalents.

Claims

1. The preparation method of the screw compressor oil with the ultra-long service life is characterized by at least comprising the following steps:

2/3 of the total amount of the base oil is added into the kettle;

adding the residual 1/3 of the base oil into the kettle, adding the demulsifier and the antifoaming agent into the kettle, stirring and mixing for 1.0h by using a static mixer, and filtering out;

the preparation method of the base oil comprises the following steps:

wherein the content of the poly-alpha-olefin is 45% of the mixed base oil by mass, the content of the oil-soluble polyether is 10% of the mixed base oil by mass, and the content of the gas-making oil is 45% of the mixed base oil by mass;

the detergent adopts low-base number synthetic sulfonate, medium-base number sulfonate and medium-base number sulfurized alkylphenate,

the dispersant adopts high-activity polyisobutylene succinimide,

the viscosity index improver adopts polymethacrylate,

the antioxidant adopts mixed tert-butyl phenol,

the antioxidant corrosion inhibitor adopts secondary alcohol group zinc dialkyl dithiophosphate,

the antifriction agent adopts molybdenum dialkyl dithiocarbamate and tricresyl phosphate,

the rust inhibitor adopts benzene triazole octadecylamine and dodecenyl succinic acid half ester,

the demulsifier adopts diamine propylene oxide polymer,

the anti-foaming agent adopts a composite anti-foaming agent;

the composition of various raw materials comprises the following components in percentage by mass:

86.0% of base oil; low base number synthetic sulfonate, 0.5%; medium-base sulfonate, 1.25%; medium base sulfurized alkylphenate, 0.75%; 3% of high-activity polyisobutylene succinimide; polymethacrylate, 3.5%; 1.0 percent of mixed tert-butyl phenol; zinc dialkyl dithiophosphate, secondary alcohol group, 0.75%; molybdenum dialkyl dithiocarbamate, 0.75%; tricresyl phosphate, 1.0%; 0.75% of benzotriazole octadecylamine; dodecenyl succinic acid half ester, 0.75%; diamine propylene oxide polymer was added, 100ppm; adding 100ppm of composite antifoaming agent;

wherein the viscosity index of the screw compressor oil is not less than 128, and the kinematic viscosity at 40 ℃ is 68.86mm ² S, kinematic viscosity at 100 ℃ of 10.01mm ² /s。

2. The method of producing screw compressor oil according to claim 1,

adding 86.0kg of 2/3 mixed base oil into a kettle, adding 3.5% of polymethacrylate, heating to 65-70 ℃, stirring for 0.5h, adding 0.5% of low-base-number synthetic calcium sulfonate, 1.25% of medium-base-number calcium sulfonate, 0.75% of sulfurized calcium alkyl phenol, 3% of high-activity polyisobutylene succinimide, 1.0% of mixed tert-butyl phenol, 0.75% of secondary alcohol-based dialkyl zinc dithiophosphate, 0.75% of molybdenum dialkyl dithiocarbamate, 1.0% of tricresyl phosphate, 0.75% of benzotriazole octadecylamine, and 0.75% of dodecenyl succinic acid half ester, stirring for 1h, mixing for 2.0h through a serial static mixer, adding the rest 1/3 mixed base oil, 100ppm of diamine propylene oxide polymer and 100ppm of composite antifoaming agent, and stirring and mixing for 1.0h through a stirring and static mixer.