Francool Technology (Shenzhen) Co., Ltd.

HomeIndustry > Aerospace
Aerospace

Aviation lubricants: Generally refers to the aircraft and ground airport equipment using oil products, including aviation engine oil, aviation transmission system oil, aviation grease three categories.

Different aero-engine manufacturers have introduced and developed their own aero-engine oil specifications, such as Pratt & Whitney's PWA521 specification, GE's D50TF1 specification, and Allison's EMS53 specification, SAEE34 also developed an aviation gas turbine SAEAS5780, which specifies the basic physical and chemical properties of gas turbine oils with viscosities of 5 mm2 / s for use in turbo-engine or turbine-driven marine and industrial equipment.

Currently the major international aviation engine oil specifications are still dominated by the US military specifications, such oil products need to focus on oil storage stability under high and low temperature conditions, oxidation stability and corrosion.

The piston engine, which was originally used as an aircraft-powered aero engine, culminated in piston engine technology after World War II baptism; with the worldwide economic growth, the piston engine was no longer able to adapt to high-speed, high Endurance, low energy consumption of large aircraft, such as transport aircraft, passenger aircraft needs, and with the advent of aviation turbine engines, and gradually withdraw from the field of air transport. As a result, human aviation began to enter the jet age.

After about 60 years of technological progress, the turbine engine has been developed from a turbojet engine to a turbofan engine, greatly improving the safety, stability and economy of the aircraft.

With the development of aeroengine technology, progress and performance improvement, the working harshness of the engine also continues to increase. For example, modern turbofan engine parts require stable and reliable work at about 1200-1500 ℃, the required aeroengine lubricating oil quality The level is also increased. To meet the reliability requirements of this aero-engine for lubricants, aero-engine oil standards have also emerged.

Aero-engine oil, as the blood of aeroengine, is a kind of high-performance aero-engine lubricating oil, which not only provides sufficient lubrication for all moving parts of aeroengine, but also provides sufficient sealing and cooling functions to protect the aeroengine at high speed and high temperature Under the safe, stable long battery life.

1.1 aviation engine oil specifications and main performance

1.1.1 engine lubricating oil system

In order to ensure the safety and stability of the aeroengine, it is necessary to provide a steady flow of lubricating oil to each lubricating part of the engine by means of a lubricating system. Lubrication system design can be divided into two stages, the engine put into use before the 1980s basically adopts the traditional lubrication system, as shown in Fig.3. The new generation of aero-engine lubrication system is based on the traditional lubrication system, further improved to make it safer and more reliable work to ensure the normal supply of lubricants.

1.1.2 Aeroengine oil specifications

Aeroengine lubricating oil lubrication system through the lubricating parts of the engine effectively lubricated at the same time, take away a large number of lubricated parts absorbed by the combustion of fuel generate a lot of heat, the engine to maintain a certain working temperature stable operation. Therefore, the lubricant in the cycle, you need to experience endothermic, heating, oxidation, cooling cycle of the process of continuous cycling. In this process, the oil produces evaporation, coking, corrosion and other reaction tendencies. This raises very demanding requirements for aero-engine lubricants. Measuring a lubricant can meet the basic requirements of aircraft engines, mainly by the specifications to be limited.

The development and change of aeroengine specifications is compatible with the development of aeroengine technology. Different aero-engine manufacturers have introduced and developed their own aero-engine oil specifications, such as Pratt & Whitney's PWA521 specification, GE's D50TF1 specification, and Allison's EMS53 specification, SAEE34 also developed an aviation gas turbine SAEAS5780, which specifies the basic physical and chemical properties of gas turbine oils with viscosities of 5 mm2 / s for use in turbo-engine or turbine-driven marine and industrial equipment. However, on the whole, they are all based on US military standards. The required base oil has also gradually evolved from the initial mineral oil type and semi-synthetic type to the double ester type synthetic oil until the current neopentyl polyol ester synthetic oil. The American aviation engine oil standard is divided into two specifications according to the viscosity of oil at 100 ° C. One is the MIL-L-7808 specification, which specifies two viscosity grades of 3 mm2 / s and 4 mm2 / s, the former for general use and the latter for applications with higher thermal stability requirements, which was released in 1951 and has been Revised many times; the second is the MIL-L-23699 specification, provides a viscosity level 5mm2 / s, the specification was released in 1963, so far there have been more than one version, and has been gradually improved, the provisions of the oil includes STD, C / I and HTS. The two currently used specifications are the MIL-PRF-7808L specification and the MIL-PRF-23699F specification released in May 1997.

1.2 Aviation engine oil products and manufacturing plants

Domestic aviation engine oil is basically divided into synthetic and mineral two.

Aviation hydraulic / aviation lubricants

Aviation hydraulic oil is mainly used as hydraulic fluid transmission mechanism working fluid, but also a variety of demanding hydraulic machinery ideal working medium. Has a good high temperature performance, viscosity temperature, shear resistance, oxidation stability and hydraulic transmission performance, temperature of -54 ℃ -135 ℃. Anti-oxidation stability to meet a variety of new aircraft hydraulic system requirements.

Since the 1950s, the U.S. Air Force has been working on the research of advanced aviation hydraulic fluids. From petroleum-based to phosphate-based to poly-alpha-olefins (PAO) for hydrocarbon synthesis, increased flame resistance has been a major driver for the development of new aviation hydraulic fluids. In addition, due to the increasing awareness of environmental protection, the biodegradability and low toxicity of hydraulic oil have become more and more important. It is a trend to replace the anti-rust hydraulic oil with aviation hydraulic oil. The future, with the continuous improvement of aircraft performance, high temperature hydraulic oil has also become the development direction.

2.1 aviation hydraulic oil specifications

15 aviation hydraulic oil GJB1177-1991

Mainly used for aviation hydraulic transmission work fluid, alternative domestic 10, 12 aviation hydraulic oil and the United States MIL-H-5606E hydraulic oil.

No. 10 aviation hydraulic oil (sky) SH0358-1992 mainly used for working fluid hydraulic transmission mechanism, but also can be used for other high-performance hydraulic system working fluid. Such as CNC machine tools, acetamide circulating pump, high pressure ethylene pump and ship crane, deck machinery, excavators, windlass, large cranes, radar cars and railways, electrical switches. As the product has a very low freezing point, it can also be used for arctic areas of the above equipment and alternative cold oil. Operating temperature above -70 ℃. 10 aviation hydraulic oil (ground oil) Q / SYYM0024-2000

This product is mainly used for a variety of hydraulic systems require higher working fluid, as well as the airport and the cold ground with a variety of hydraulic machinery and equipment. Such as CNC machine tools, ethanolamine circulating pump, high pressure ethylene pump and ship crane, deck machinery, excavators, windlass, large cranes. Operating temperature above -50 ℃.

2.2 aviation hydraulic oil products and production

China National Petroleum Yumen Petrochemical Plant

With the great support from China National Petroleum Corporation, the People's Liberation Army, the People's Liberation Army, and the military forces stationed in the military, the Yumen Refinery and Petrochemical Plant and the Air Force Research Institute of Oil and Gas began joint research and development work on hydraulic oil No. 15 from 1988 , Developed by the oil analysis and evaluation of all technical indicators in line with the requirements of the US MIL-H-5606E standards, and passed the bench test and F-8 and other types of flight test, trial test, alternative domestic 10, 12 aviation hydraulic oil The production process successfully passed the appraisal of the domestic aviation fuel appraisal committee and unanimously held that the production process of the aviation hydraulic oil No. 15 of Yumen Refinery and Petrochemical Plant is stable and the index of product name meets the requirements, especially the shear stability, oxidation stability and Compared with the 12th aviation hydraulic oil, the low temperature property is obviously improved. Compared with the MIL-H-5606E standard hydraulic oil in the United States, there is no obvious difference, and it is agreed to put into production and be used by users. In 2000, the blending and filling system was reformed as a whole to realize the automatic filling and packing of oil products in the clean workshop, further stabilizing the quality of the products and completely replacing the import of aviation hydraulic oil and at the same time meeting the requirements of military and civil aviation need.

Aviation grease / aviation lubricants

Aerospace Grease is mainly used for aircraft instrumentation and control components, demanding low-temperature performance, as well as some high-temperature grease on the landing and moving parts.

3.1 Specifications and products

2 low-temperature grease (Yumen)

Used in aircraft operating lever system protection and lubrication, a variety of precision instruments and radio equipment, and light load, high speed, wide temperature range (-60 ℃ ~ 120 ℃) ​​of various mechanical equipment, rolling bearings and plain bearings and other Wear parts lubrication.

2 aviation grease (Fushun production)

2 aviation grease has excellent low temperature performance, high temperature performance and water resistance, can be used for a wide temperature range of ball bearing lubrication, the use of temperature -50 degrees -120 degrees. Has excellent high and low temperature performance, mechanical stability, colloidal stability and oxidation stability.

Suitable for bearing of aviation motor and micromotor, the fulcrum of gear and control mechanism, the connection part and the lubrication of some instruments and meters. The aviation grease is also suitable for the lubrication of high-speed ball bearing. At 5000 ~ 20000r / min, The last fatliquoring use period of 3 years, is the use of 2 #, 3 # spindle lubrication life six times. Aerospace grease instead of 5 #, 7 #, 10 # spindle oil, lubrication costs can be significantly reduced. Aviation grease used in continuous spinning machine spindle bearings 2000 / min, fatliquoring interval can be extended to six months. For 3600r / min air spinning split spindle bearings, grease intervals can be extended to three months. Aerospace grease can be used for bearing lubrication of ball bearings (such as DC shaver) and cryogenic fluid delivery pumps (such as methane and ethane reflux pump) motors for mechanical and electrical equipment outdoors operating in cold regions.

7007,700 Aviation Grease (Ping Production)

Specially designed for aviation lubrication, it is a multi-purpose aviation grease suitable for bearings and gears of aeronautic machines, fulcrums of operating mechanisms, assembly joints and lubrication of some instruments and meters. It is also suitable for lubrication of high-speed ball bearings.

This product is also suitable for non-aviation field, used in 5000r / min ~ 20000r / min grinder spindle, 2000r / min continuous work of spinning twisting machine spindle bearings, 3600r / min air spinning split spindle bearings and outdoor work in cold areas Mechanical and electrical equipment such as ball bearings (such as DC generators), instrumentation, motor bearings, high-speed home micro-motor (such as household grinder, electric razor) and cryogenic liquid pump (such as methane, ethane reflux pump) Lubrication.

Wide temperature and temperature aviation grease (China Petroleum and Chemical Research Institute production)

Suitable temperature (-60 ℃ ~ 300 ℃) Designed for aerospace equipment development, the specific performance and confidentiality specifications.

Extreme pressure and grease wear resistance performance indicators and significance / aviation lubricants

Lubrication of equipment with a large load Add certain extreme pressure or anti-wear additives in the grease to improve the extreme pressure and anti-wear properties of the grease. Extreme pressure anti-wear grease performance is a very important indicator of extreme pressure anti-wear performance is poor, it will lead to serious wear and tear of the equipment,

Lubrication of equipment with a large load Add certain extreme pressure or anti-wear additives in the grease to improve the extreme pressure and anti-wear properties of the grease. Extreme pressure and anti-wear grease performance is a very important indicator of extreme pressure and wear resistance is poor, it will lead to serious wear and tear of equipment, equipment damage caused by equipment accidents.

On the extreme pressure, anti-wear properties of the determination of four ways:

1 Timken test

The test is carried out on a TICKKEN TEST MACHINE, the grease at a certain flow rate is added to a certain load speed of the metal ring and friction between the metal block. After a certain period of time after the operation of the observed wear on the metal block to determine the extreme pressure performance of grease with OK value.

1.1 Inspect the ability of grease to withstand load under linear contact.

1.2 Test Method: SH / T 0203

2 four-ball test (GB / T 3142)

Four ball test is to grease into the ball box, under the provisions of the load on the top of a steel ball below the stationary three ball rotation at a certain speed. Measured after a certain period of time to determine the diameter of the grease extreme pressure performance.

This method has three kinds of representation: PB value, PD value, ZMZ value

PB value: refers to the maximum load in the test conditions do not bite, with N said.

PD value: is the minimum load at which the rotating ball and three stationary balls sinter under the test conditions, expressed in N.

ZMZ Value: An index of grease resistance to extreme pressure under applied load. The test load 0.1 units incrementally added to the interval of three static steel ball, take the sintering load of the first ten test results ZMZ value calculated with N said.

3 four-ball test (GB / T12583) This method has three representation methods: PB value, PD value, LWI value

LWI value: refers to the lubricant under the load to minimize wear and extreme pressure capacity index. Under this test condition, it is equal to the average of the corrected load measured ten times by applying 0.1 log unit load to the three stationary balls before the sintering point.

4 wear resistance (SH / T 0204)

In the four ball long grinding test machine, under the specified load conditions, the top of the ball against the surface of the sample coated with the following three static rotation of the ball, the test after the measurement of the following three ball wear scar diameter, Wear scar size to determine the size of the anti-wear grease performance.

4.1 Significance: This method is used to determine the relative wear performance of different greases under test conditions. It is not possible to distinguish extreme-pressure and non-extreme-pressure greases.