欧美人妻精品一区二区三区99,中文字幕日韩精品内射,精品国产综合成人亚洲区,久久香蕉国产线熟妇人妻

Sizes range from 2 mm to 6 m

Bearings vary in size from small to large. The smallest “miniature bearing” in the world is 0.6 mm in inner diameter, 2.0 mm in outer diameter and 0.8 mm in thickness. Large bearings, with an outer diameter of 6 meters and a weight of more than 15 tons, are used in large shield machines for tunneling. This type of shield machine was used in the excavation of a cross sea tunnel under the Dover Strait, which connects Britain and France, and this large bearing was used.

400000 rpm

Dental drill (commonly known as dental handpiece) is equipped with a bearing that can rotate at a super high speed. These are two ultra precision bearings with inner diameter of 3.0 mm × outer diameter of 6.0 mm × width of 2 mm and steel ball diameter of 1.0 mm. They can rotate at an amazing speed of “400000 revolutions per minute”, which greatly reduces the vibration of dental handpieces and greatly reduces the pain of patients during treatment.

Peering the world of bearings from the perspective of numbers 2

The speed of steel ball is 160 meters per second

The main shaft bearing used in the V2500 jet engine of international airliner has a rolling speed of 160 meters per second, equivalent to 580 kilometers per hour. It is because of the use of high-performance and high-speed bearings that the engine can run safely for a long time and transport passengers safely to all parts of the world.

Amplitude below 100 nm

It is no exaggeration that “the accuracy of the machine depends on the rotation accuracy of the bearing”. The two ends of the rotating shaft are supported by two bearings. If the shaking of the axis is large, the mechanical performance cannot be improved. Wechat of metal processing has good content and deserves attention. The “hard disk”, a computer external storage device with ultra precision bearings, has an axial amplitude of less than 100 nm (1 nm = 1 / 1000000 mm). The key to achieve such ultra-high precision is the accuracy of rolling elements such as “steel ball” and “roller”.

Peering the world of bearings from the perspective of numbers 3

Working in space for 15 years

The development of the universe is inseparable from bearings. Weather forecast, satellite radio and television signals, automobile satellite positioning information, etc., are provided by satellites flying around the earth. The satellite is equipped with a gyroscope to maintain the attitude and course of the satellite, and the gyroscope is equipped with ultra precision bearings. This kind of bearing can work continuously in space for 15 years.

A world of 253 degrees below zero to 500 degrees above zero

The bearings in the liquid fuel pump of space rocket are the bearings with the lowest temperature. The bearing operates in liquid hydrogen at minus 253 ℃. The special high performance bearing used in medical CT scanner is the typical representative of the bearing used in high temperature environment. In X-ray vacuum tubes with temperatures up to 300 to 500 ℃, the bearings can also operate continuously to protect our health.

Peering the world of bearings from the perspective of numbers 4

亚洲综合无码一区二区丶| 久久久久久久 亚洲精品| 看一下日本人插逼逼洞视频| 日本亚欧乱色视频69室| 粉嫩小穴被大鸡巴操视频在线观看| 波多野结衣浴尿解禁在线| 午夜场射精嗯嗯啊啊视频| 加勒比在线不卡一区二区观看| 中文字幕人妻一区二区三区久久| 欧美性爱撅臀插入啪啪啪| 鸡巴和逼中国美女| 69国产精品久久久久久人| 无码一区二区三区色哟哟| 亚洲av一区二区在线看| 欧美猛男一区二区三区快播| 少妇被黑人入侵在线观看| 2021国产一区二区岛国| 婷婷6月天丁香综合在线| 亚洲av熟妇高潮精品啪啪| 三级成人国产高清视频| 成人精品视频区一区二区三| 中国女人日逼免费片| 99久久久国产精品k影| 日韩av一区二区三区激情在线| 国产精品日韩精品欧美精品| 人妻在线系列一区二区三| 一级风流国产片a级| 国产无码福利一区| 欧美一区二区高清视频在线观看| 日韩欧美一二三区| 精品区在线导航视频观看| 中文字幕在线观一二三区| 欲色欲香天天网综合久久| 极品一区二区三区av| 国语自产免费精品视频在| 青青河边草直播免费观看| 男人操女人黄片黄色| 91精品欧美久久久久久| 成人男女做爰免费视频网| 国内精品久久久久精品97| 国产乱子伦视频一区二区三区|