A high-speed motor train unit gear box lubricating composition and a method for preparing the same

Abstract

The application discloses a high-speed motor train unit gear box lubricating composition and a preparation method thereof, which comprises the following components in parts by weight: anti-scratching agent 2.0-6.0 parts; extreme pressure anti-wear agent 0.8-3.8 parts; friction-reducing additive 0.5-2.8 parts; anti-oxidation and anti-corrosion agent 0.1-0.5 parts; metal deactivator 0.1-0.2 parts; anti-rust agent 0.05-0.25 parts; anti-foaming agent 0.01-0.06 parts; viscosity index improver 1-7 parts; ester oil 4-16 parts; HVIS150BS 1-9 parts; PAO6 and PAO4 the rest. The high-speed motor train unit gear box lubricating composition has good anti-scratching, anti-wear, load-carrying, friction-reducing, anti-corrosion, anti-rust, anti-foaming and thermal oxidation stability, especially has excellent temperature rise inhibition capacity, and is suitable for lubricating a gear box of a motor train unit with a speed of 450 km / h.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of lubricating oil, and particularly relates to a high-speed motor train unit gear box lubricating composition and a preparation method thereof. BACKGROUND

[0002] The gear box is a core unit for energy transmission of the high-speed motor train unit. After years of rapid development, domestic motor train unit gear box research and manufacturing enterprises have mastered the manufacturing technology of the gear transmission system of the 160-350 km / h grade and harmonious motor train unit, and replaced imported products, thus effectively supporting the strategy of self-determination of key core components. In order to further improve the international competitiveness of China's rail transit equipment technology and realize the goal of leading the development of the world's high-speed motor train gear transmission technology, it is necessary to break through the technical problems such as temperature rise and abnormal wear of the high-speed rail gear transmission system at a speed of 400 km / h and above.

[0003] As the lubricating medium of the high-speed rail gear box, the high-speed rail gear oil not only needs to avoid gear wear, but also needs to play a role in heat dissipation and cooling. Due to the continuous increase of high-speed rail speed, the heat generated by gear meshing and oil agitation is increasing, resulting in continuous increase of gear oil temperature. High oil temperature will trigger the protection device of the train, causing the train to run at a reduced speed, interfering with the normal traffic order, and causing certain economic losses and adverse social impact.

[0004] In order to meet the demand for reducing temperature rise of high-speed rail gear box lubrication at a speed of 450 km / h, it is necessary to reduce the kinematic viscosity of the lubricating oil. Although this is beneficial to reduce the temperature rise caused by high-speed agitation, it also brings the risk of abnormal wear. Therefore, it is necessary to increase the content of extreme pressure anti-wear agent, which will cause problems such as corrosion and thermal oxidation stability. In addition, friction-reducing additives can be added to reduce friction and inhibit temperature rise, but the addition of friction-reducing additives competes with the extreme pressure anti-wear agent for surface adsorption, reducing the effect of the extreme pressure anti-wear agent. In order to solve the above problems, it is necessary to carefully balance the types and amounts of various additives in order to meet the lubrication requirements of the gear box. SUMMARY

[0005] Therefore, the application aims to provide a high-speed motor train unit gear box lubricating composition and a preparation method thereof to solve at least one technical problem in the background art.

[0006] Compared with the prior art, the high-speed motor train unit gear box lubricating composition and the preparation method thereof have the following advantages: under the premise of maintaining excellent antioxidant, rust and corrosion resistance, extreme pressure and wear resistance, and anti-foam performance, the composition has excellent temperature rise inhibition effect, and the highest temperature can be reduced by 15 DEG C under the same speed grade compared with the existing Fuxing motor train unit gear box lubricating oil. BRIEF DESCRIPTION OF DRAWINGS

[0007] The accompanying drawings, which form a part of this application, are intended to provide further understanding of the application and are incorporated herein in their entirety, and they illustrate one or more exemplary embodiments of the present application and together with their description serve to explain the present application. In the drawings:

[0008] Figure 1 Figure for the temperature rise inhibition performance of Example 1 and Comparative Example of the present application. DETAILED DESCRIPTION

[0009] It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict.

[0010] The present application will be described in detail below with reference to the accompanying drawings and embodiments.

[0011] In the following examples, isobutylene sulfide was purchased from Shenyang Guangda Chemical Co., Ltd., code T321. Acidic phosphate ester amine salt was purchased from Shenyang Hualun Lubricating Oil Additives Co., Ltd., code T308; anti-micropitting extreme pressure anti-wear agent (self-made), code QT301; triphenyl thiophosphate was purchased from Jinzhou Shengda Chemical Co., Ltd., code T309; dialkyl dithiophosphate derivative was purchased from BASF, code IR353; thiocarbamate was purchased from Shenyang Hualun Lubricating Oil Additives Co., Ltd., code T323. Nitrogen-containing borate esters were purchased from Suzhou Jinmo Runcheng Lubricating Technology Co., Ltd., code GM1011; antimony dialkyl dithiophosphate was purchased from Vanderbilt GmbH, code V622; antimony dialkyl dithiocarbamate was purchased from Baoji Weibin District Kelong Chemical Glassware Instrument Procurement Station, code HL622; molybdenum dialkyl dithiophosphate was purchased from Luoyang Pacific United Petrochemical Co., Ltd., code POUPC1001; molybdenum dialkyl dithiocarbamate was purchased from Luoyang Pacific United Petrochemical Co., Ltd., code POUPC1002; molybdenum ammonium ester was purchased from Luoyang Pacific United Petrochemical Co., Ltd., code POUPC1003; hindered phenolic glycerol was purchased from BASF, code FA10. Benztriazole enoic acid adduct was purchased from Shenyang Hualun Lubricating Oil Additives Co., Ltd., code T406E; thiadiazole derivatives were purchased from Luoyang Pacific United Petrochemical Co., Ltd., code POUPC6001-8. High-alkalinity calcium sulfonate was purchased from Xinxiang Ruifeng New Materials Co., Ltd., code RF1106D; low-alkalinity calcium sulfonate was purchased from Xinxiang Ruifeng New Materials Co., Ltd., code RF1104. High-molecular-weight organosilicon derivative rapid defoamer was purchased from Luoyang Pacific United Petrochemical Co., Ltd., code HL-933S; polysiloxane + ester derivative defoamer was purchased from Luoyang Pacific United Petrochemical Co., Ltd., code HL-933. Polymethyl methacrylate viscosity index improver was purchased from Dalian Xinyiye New Materials Development Co., Ltd., code V6520. Pentaerythritol fatty acid esters were purchased from Croda, code 3970; PAO40 and PAO6 base oils were purchased from Mobil; Group I deep refined mineral oil was purchased from Suzhou Zhuxin Industrial Lubricating Oil Co., Ltd., code HVIS150BS.

[0012] The process for making QT301 is as follows:

[0013] 1) Take a 500ml three-necked flask, add a certain amount of phosphorus pentoxide to 100ml of petroleum ether (boiling range 90-120℃) solvent, and stir to disperse it evenly (about 3 minutes).

[0014] 2) While stirring, add a certain amount of isooctanol dropwise using a dropping funnel, controlling the temperature of the reaction solution below 40℃ during the addition. After the addition is complete, raise the temperature to 72-75℃ and react for 4 hours to obtain the intermediate product (acidic phosphate ester).

[0015] 3) After cooling the intermediate product, add a certain amount of T152 (polyisobutylene bis(succinimide)) and dodecylamine, then heat to 90-94℃ and react for 3 hours.

[0016] 4) After removing the petroleum ether solvent by distillation, QT301 is obtained.

[0017] Example 1

[0018] This embodiment provides a lubricating composition for a high-speed train gearbox and its preparation method, with the following specific components (by mass percentage):

[0019] Anti-scratch agent (T321) 3.35%, extreme pressure anti-wear agent (QT301:T308:T309:T323, IR353=2:1:1:2:2.3) 1.66%, friction reducing additive (POUPC1002:HL622=1:1) 0.90%, metal deactivator (POUPC6001-8:T406E=1:2) 0.15%, antioxidant and anti-corrosion agent (RF2203) 0.2%, rust inhibitor (RF1106D) 0.05%, antifoaming agent (HL933:HL933S=1:1) 0.02%, viscosity index improver (V6520) 5%, ester oil (3970) 9%, HVIS150BS 5%, PAO (PAO6 and PAO40) balance.

[0020] The preparation method is as follows:

[0021] The above raw materials are mixed (first adding solid additives and a small amount of additives, then adding a large amount of additives, and finally adding base oil), heated to 66°C and stirred for 1.5 h to obtain the aforementioned high-speed train gearbox lubrication composition.

[0022] Example 2

[0023] This embodiment provides a lubricating composition for a high-speed train gearbox and its preparation method, with the following specific components (by mass percentage):

[0024] Anti-scratch agent (T321) 3.35%, extreme pressure anti-wear agent (QT301:T323:T308:T309:IR353=9:2:2:4:4.6) 2.16%, friction reducing additive (POUPC1002:POUPC1003:V622=4:2:5) 1.1%, metal deactivator (POUPC6001-8:T406E=5:8) 0.13%, rust inhibitor (RF1106D) 0.05%, antifoaming agent (HL933:HL933S=1:1) 0.04%, viscosity index improver (V6520) 5%, ester oil (3970) 9%, HVIS150BS 5%, PAO (PAO6 and PAO40) balance.

[0025] The preparation method is the same as in Example 1.

[0026] Implement column 3

[0027] This embodiment provides a gearbox oil composition with good temperature rise suppression effect, the specific composition of which is as follows (by mass percentage):

[0028] Anti-scratch agent (T321) 3.6%, extreme pressure anti-wear agent (QT301:T308:T309:IR353=9:7:4:4.6) 2.46%, friction reducing additive (POUPC1001:HL622=8:5) 1.30%, metal deactivator (T406E) 0.10%, antioxidant and anti-corrosion agent (RF2202) 0.3%, rust inhibitor (RF1104) 0.2%, antifoaming agent (HL933) 0.03%, viscosity index improver (V6520) 5%, ester oil (3970) 9%, HVIS150BS 4%, PAO (PAO6 and PAO40) balance.

[0029] The preparation method is the same as in Example 1.

[0030] To evaluate the performance of this invention, conventional high-speed rail gear oil was used as a comparative example. Meanwhile, to demonstrate the excellent temperature rise suppression effect of this invention, other friction-reducing additives not covered by this invention were used to blend the comparative example.

[0031] Comparative Example 1

[0032] Anti-scratch agent (T321) 3.35%, extreme pressure anti-wear agent (QT301:T308:T309:T323:IR353=2:1:1:2:2.3) 1.66%, friction reducing additive (GM1011:F10A=1:1) 0.90%, metal deactivator (POUPC6001-8:T406E=1:2) 0.15%, antioxidant and anti-corrosion agent (RF2203) 0.2%, rust inhibitor (RF1106D) 0.05%, antifoaming agent (HL933:HL933S=1:1) 0.02%, viscosity index improver (V6520) 5%, ester oil (3970) 9%, HVIS150BS 5%, PAO (PAO6 and PAO40) balance.

[0033] The preparation method is the same as in Example 1.

[0034] Comparative Example 2

[0035] Anti-scratch agent (T321) 3.35%, extreme pressure anti-wear agent (T308:T309:T323:IR353=3:1:2:2.3) 1.66%, friction reducing additive (GM1011:F10A=1:1) 0.90%, metal deactivator (POUPC6001-8:T406E=1:2) 0.15%, antioxidant and anti-corrosion agent (RF2203) 0.2%, rust inhibitor (RF1106D) 0.05%, antifoaming agent (HL933:HL933S=1:1) 0.02%, viscosity index improver (V6520) 5%, ester oil (3970) 9%, HVIS150BS 5%, PAO (PAO6 and PAO40) balance.

[0036] The preparation method is as described in Example 1.

[0037] Comparative Example 3

[0038] Anti-scratch agent (T321) 3.35%, extreme pressure anti-wear agent (QT301:T323:T309:IR353=3:1:2:2.3) 1.66%, friction reducing additive (GM1011:F10A=1:1) 0.90%, metal deactivator (POUPC6001-8:T406E=1:2) 0.15%, antioxidant and anti-corrosion agent (RF2203) 0.2%, rust inhibitor (RF1106D) 0.05%, antifoaming agent (HL933:HL933S=1:1) 0.02%, viscosity index improver (V6520) 5%, ester oil (3970) 9%, HVIS150BS 5%, PAO (PAO6 and PAO40) balance.

[0039] The preparation method is as described in Example 1.

[0040] Comparative Example 4

[0041] Anti-scratch agent (T321) 3.35%, extreme pressure anti-wear agent (QT301:T323:T308:IR353=3:1:2:2.3) 1.66%, friction reducing additive (GM1011:F10A=1:1) 0.90%, metal deactivator (POUPC6001-8:T406E=1:2) 0.15%, antioxidant and anti-corrosion agent (RF2203) 0.2%, rust inhibitor (RF1106D) 0.05%, antifoaming agent (HL933:HL933S=1:1) 0.02%, viscosity index improver (V6520) 5%, ester oil (3970) 9%, HVIS150BS 5%, PAO (PAO6 and PAO40) balance.

[0042] The preparation method is as described in Example 1.

[0043] Comparative Example 5

[0044] Anti-scratch agent (T321) 3.35%, extreme pressure anti-wear agent (QT301:T323:T308:T309:IR353=9:2:2:4:4.6) 2.16%, friction reducing additive (GM1011:POUPC1003=5:6) 1.1%, metal deactivator (POUPC6001-8, T406E) 0.13%, rust inhibitor (RF1106D) 0.05%, antifoaming agent (HL933, HL933S) 0.04%, viscosity index improver (V6520) 5%, ester oil (3970) 9%, HVIS150BS 5%, PAO (PAO6 and PAO40) balance.

[0045] The preparation method is the same as in Example 1.

[0046] Comparative Example 6

[0047] Anti-scratch agent (T321) 3.35%, extreme pressure anti-wear agent (QT301:T323:T308:T309:IR353=9:2:2:4:4.6) 2.16%, friction reducing additive (F10A:POUPC1003=5:6) 1.1%, metal deactivator (POUPC6001-8:T406E=5:8) 0.13%, rust inhibitor (RF1106D) 0.05%, antifoaming agent (HL933:HL933S=1:1) 0.04%, viscosity index improver (V6520) 5%, ester oil (3970) 9%, HVIS150BS 5%, PAO (PAO6 and PAO40) balance.

[0048] The preparation method is the same as in Example 1.

[0049] Comparative Example 7

[0050] Anti-scratch agent (T321) 3.35%, extreme pressure anti-wear agent (QT301:T323:T308:T309:IR353=9:2:2:4:4.6) 2.16%, friction reducing additive (POUPC1002:GM1011=5:6) 1.1%, metal deactivator (POUPC6001-8) 0.13%, rust inhibitor (RF1106D) 0.05%, antifoaming agent (HL933:HL933S=1:1) 0.04%, viscosity index improver (V6520) 5%, ester oil (3970) 9%, HVIS150BS 5%, PAO (PAO6 and PAO40) balance.

[0051] The preparation method is the same as in Example 1.

[0052] Key performance comparison between the examples and comparative examples:

[0053] The key properties of the embodiments and comparative examples were examined, including scratch resistance, abrasion resistance, load-bearing capacity, corrosion resistance, rust prevention, thermal oxidation stability, and temperature rise suppression.

[0054] The temperature rise suppression test was conducted on a four-ball testing machine produced by Xiamen Tianji Automation Co., Ltd.: the room temperature was controlled between 23.2-23.5℃, the test oil was heated to 40℃ and then heating was stopped. Then the test was started under a certain load and speed. When thermal equilibrium was reached, that is, when the temperature no longer rose (the temperature remained unchanged within 2 minutes), the test was stopped. The lower the thermal equilibrium temperature, the stronger the oil's ability to suppress temperature rise.

[0055] The thermal oxidation stability test was conducted using a self-developed method: 200 mL of test oil was added to a 250 mL beaker. A No. 45 steel sheet (45 mm × 45 mm × 2 mm) was immersed in the test oil at approximately a 30° angle to the bottom of the beaker. The beaker was then placed in an oven at 135 ℃ for 72 h. Afterward, the steel sheet was removed, rinsed with petroleum ether, and the discoloration of the steel sheet was observed, along with the deposits at the bottom of the beaker. The steel sheet was graded as follows: 0: No discoloration; 1: Slight discoloration, almost identical to a new sheet; 2: Localized pale white; 3: Pale white, shiny after wiping; 4: Red, yellow, blue, gray, or other colors, or with grayish-white deposits; 5: Localized grayish-black, obvious corrosion; 6: Grayish-black, peeling. Deposits at the bottom of the beaker were categorized as abundant, medium, scarce, or absent.

[0056] Specific results are shown in Tables 1-2 and 2-2. Figure 1 .

[0057] Table 1. Key Performance Characteristics of the Implemented Series and Existing Oils

[0058]

[0059] Table 2 Main performance of Example 1 and self-adjusting comparative example

[0060]

[0061] As can be seen from the results in Tables 1 and 2, the anti-wear and friction-reducing properties of the different comparative examples are lower than those of the examples, indicating that the lubricating oil composition of the present invention has good friction-reducing and anti-wear properties, and is suitable for high-speed train gearbox lubrication. In addition, the composition of the present invention has excellent thermal oxidation stability and a long service life.

[0062] from Figure 1 The results show that the temperature rise suppression effect of the example is better than that of the existing high-speed iron oil comparative example and the self-adjusting comparative example.

[0063] Table 1-2 and Figure 1 The results show that the composition of the present invention has excellent anti-scratch, anti-wear, load-bearing, anti-corrosion, anti-rust, thermal oxidation stability and temperature rise suppression properties.

[0064] The composition of Example 1 showed good temperature rise suppression effect in the high-speed rail gearbox bench test at a speed of 400 km / h. Under the condition of room temperature of 34.2℃, the highest bearing temperature in the 3-hour full power test was 110℃ (lower than the set alarm temperature of 120℃), and the composition temperature was 81.6℃.

[0065] To further illustrate the present invention, the compounding of additives in the formulation of Example 1 will be described in detail.

[0066] Anti-scratch agent (T321) 3.35%, extreme pressure anti-wear agent (QT301:T308:T309:T323:IR353=2:1:1:2:2.3) 1.66%, friction reducing additive (POUPC1002:HL622=1:1) 0.90%, metal deactivator (POUPC6001-8:T406E=1:2) 0.15%, antioxidant and anti-corrosion agent (RF2203) 0.2%, rust inhibitor (RF1106D) 0.05%, antifoaming agent (HL933:HL933S=1:1) 0.02%, viscosity index improver (V6520) 5%, ester oil (3970) 9%, HVIS150BS 5%, PAO (PAO6 and PAO40) balance.

[0067] The superior overall performance of Example 1 is closely related to the additives and their combination. Anti-scratch agent T321 possesses excellent anti-scratch and anti-sintering capabilities, which can improve the performance of oil P. D The value enables it to effectively protect gears under high load and impact load; among extreme pressure anti-wear agents, IR353 has excellent extreme pressure performance and anti-wear performance, improving the P value of oil. BWhile providing good anti-wear properties, T308 is an acidic phosphate amine salt. This agent has high activity and plays an anti-wear role under high temperature and high load, while also having a certain rust prevention effect. T309 has good extreme pressure anti-wear and thermal stability, which can improve the oil's load-bearing, anti-wear and anti-oxidation properties. QT301 has good anti-wear and sludge dispersing properties, which can enhance the oil's anti-wear and anti-oxidation properties. T323 has good anti-wear and anti-oxidation properties, which can improve the oil's anti-wear and anti-oxidation properties. Among the friction-reducing additives, POUPC1002 is molybdenum dialkyldithiocarbamate, which has excellent friction-reducing properties and can reduce the friction coefficient of oils. Its friction-reducing performance is particularly prominent at 80-120℃. During operation, the temperature of high-speed rail gearbox bearings is typically required not to exceed 120℃, which falls within the optimal temperature range for POUPC1002 to exert its friction-reducing effect. Therefore, it can effectively suppress the temperature rise of the bearings. HL622 also has good friction-reducing properties and works synergistically with POUPC1002 to jointly reduce friction and lower temperature. The metal deactivator T406E not only has excellent anti-corrosion properties, effectively improving the oil's resistance to copper corrosion, but also has rust-preventing and friction-reducing effects, making it a multifunctional additive. POUPC6001-8 has good copper corrosion inhibition properties, and when used in combination with T406E, the copper strip corrosion of the composition reaches level 1. Antioxidant and corrosion inhibitor RF2203 has a good synergistic effect with POUPC1002, which can improve the friction reduction and anti-wear performance of POUPC1002; rust inhibitor RF1106D is high-alkalinity calcium sulfonate. This agent is a detergent, but it can also be used as a rust inhibitor with excellent rust prevention effect; antifoaming agent HL933 has good defoaming / suppression effect and strong continuous stability, while HL933S has a fast defoaming speed. The combination of these two antifoaming agents can effectively inhibit the generation of foam and quickly eliminate the foam that is generated; viscosity index improver V6520 is polymethyl methacrylate, which has good shear resistance and improves the viscosity-temperature properties of oil without causing a significant decrease in oil viscosity during use; ester oil 3970 and PAO are used together to solve the problem of poor solubility of additives in PAO base oil, and also facilitate the compatibility of oil with sealing materials; the addition of an appropriate amount of Group I deep refined mineral oil HVIS150BS can increase the solubility of additives, enhance the thickness and strength of oil film, and improve the carrying capacity of oil.

[0068] The applicant declares that this invention illustrates a high-speed train gearbox lubrication composition and its preparation method through the above embodiments, but the invention is not limited to the above embodiments, that is, it does not mean that the invention must rely on the above embodiments to be implemented. Those skilled in the art should understand that any improvements to this invention, equivalent substitutions of the raw materials in the product of this invention, addition of auxiliary components, and selection of specific methods, etc., all fall within the protection scope and disclosure scope of this invention.

[0069] The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited to the specific details in the above embodiments. Within the scope of the technical concept of the present invention, various simple modifications can be made to the technical solution of the present invention, and these simple modifications all fall within the protection scope of the present invention.

[0070] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present invention will not describe the various possible combinations separately.

[0071] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A lubricating composition for a high-speed train gearbox, characterized in that: By weight percentage, including: Anti-abrasion agent 3.35%, composition T321; The extreme pressure anti-wear agent is 1.66%, with a composition of QT301:T308:T309:T323:IR353 = 2:1:1:2:2.3; Friction-reducing additive 0.90%, with a composition of POUPC1002:HL622=1:1; The metal deactivator is 0.15%, with a composition of POUPC6001-8:T406E=1:2; Antioxidant and anticorrosive agent 0.2%, composition RF2203; Rust inhibitor 0.05%, composition RF1106D; Antifoaming agent 0.02%, composition HL933:HL933S=1:1; 5% viscosity index improver, composition V6520; Ester oils: 9%, composition: 3970; HVIS150BS 5%; PAO balance, PAO is PAO6 and PAO40; The manufacturing process of QT301 is as follows: 1) Take a 500ml three-necked flask, add a certain amount of phosphorus pentoxide to 100ml of petroleum ether solvent, stir for 3 minutes to disperse it evenly. The boiling range of petroleum ether is 90-120℃. 2) Add a certain amount of isooctanol dropwise using a dropping funnel while stirring. During the dropwise addition, control the temperature of the reaction solution to be below 40℃. After the dropwise addition is complete, raise the temperature to 72-75℃ and react for 4 hours to obtain the intermediate product, acidic phosphate ester. 3) After cooling the intermediate product, add a certain amount of T152 polyisobutylene bis(succinimide) and dodecylamine, and then heat to 90-94℃ and react for 3 hours. 4) After removing the petroleum ether solvent by distillation, QT301 is obtained.

2. The method for preparing a high-speed train gearbox lubricating composition according to claim 1, characterized in that: The process includes the following steps: mixing extreme pressure anti-wear agent, anti-scratch agent, friction-reducing additive, antioxidant and anti-corrosion agent, metal deactivator, rust inhibitor, anti-foaming agent, and viscosity index improver; adding ester oil, HVIS150BS, PAO40, and PAO6; and heating to 60-70℃ and stirring for 1-2 hours.

3. The application of a high-speed train gearbox lubrication composition prepared by the method described in claim 2 in the lubrication of a high-speed train gearbox with a speed of 450 km / h.

Images