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This factory owner produces the clean ball machine, the special-purpose drawing machine, each kind of wire drawing machine, may the quality of certified level, the instruction technology, visit to serve, clean ball silk brightness is high, silk number entire, attaches few, does not have the crankpin, and guaranteed that the quality is best in the similar products, the price is most reasonable, to sells the ball silk to implement three package, is responsible.

本厂主产的清洁球机，专用拉丝机，各种拔丝机，都可以保证质量，传授技术，上门服务，清洁球丝亮度高，丝号全，接头少，无偏轴，并保证在同类产品中质量最好，价格最合理，对所售球丝实行三包，负责到底。

The effect of tribology factors on bearing vibration is studied experimentally. AR model and WPT are used to processing the normal arid abnormal signals. The results are as follows:1. The vibration of ball bearings is caused by the tribology action of contact pairs of ball and ring races and has the essential of tribo-dynamics. Any factors affecting the tribology characteristics of contact pairs will affect vibration and noise of bearings consequently.2. Vibration characteristics of bearing keep almostly unchanged with the increasing of axial load expecting the increasing of nature frequencies. When radial load increasing with axial load unchanged, nature frequencies keep unchanged but some new vibration peaks appears in the spectrum.3. Vibration amplitudes are damped and nature frequency are enhanced with sufficient lubrication. Vibration and noise of bearings increase obviously and roar can happen and the contact surfaces scratch slightly under insufficient and unclean lubrication state. Bearing will be disabled in a few minutes without any lubrication.4. Bearing vibration is unstable under low speed. With the speed increasing, the vibration become stable and natural frequencies increase slightly but the amplitudes increase apparently.5. Bearing vibration can be excited only by some harmonics ofwaviness without lubrication and by all harmonics with lubrication based on the theoretical analysis.6. The nature frequencies of ball bearings decrease with the increasing sizes. When international clearance increasing, nature frequencies decrease in radial and increase in axial and angular and the amplitudes increase in radial and decrease in axial and angular. When the number of balls increasing, nature frequencies increase and amplitudes decrease. When the pitch diameter increasing, axial nature frequency increase and others nearly keep no change. When outer race groove curvature radius increasing, nature frequencies increase in radial and decrease in axial and angular and amplitudes keep no change in radial and increase in axial and angular. When inner race groove curvature radius increasing, nature frequencies decrease and amplitudes increase.7. The distortion in amplitude and frequency components of bearing vibration signals picked up by the present probe measurement method is founded and right conclusions cannot be achieved by the signals. When accelerometer is rigidly screwed with steel stud onto a flat outer surface of a ball bearing, vibration signal can be got without distortion and the reliability of research on bearing vibration is assured.8. AR model is suitable for large samples of bearing vibration signals, square root of length of samples can be used as the upper limitation of order determination and the FPE order selection criterion is effective. Many advantages of AR spectrum are founded over the classical based on FFT.9. Time-Frequency analysis is necessary for abnormal noise of ball bearings. WPT overcomes the principle shortcomings of STFT and proved to be a best tool to process the abnormal signals.

理论分析和试验研究表明： 1球轴承振动是钢球—滚道接触副中的各种摩擦学作用引起的，具有摩擦动力学的本质，任何对接触副的摩擦学特性有影响的因素都将对球轴承的振动和噪声特性产生影响； 2中心轴向载荷作用下，载荷增大使球轴承的固有振动频率升高，载荷越大同样的载荷增幅引起的频率升幅减小，足够大的中心轴向载荷作用下载荷的变化对球轴承振动的频率特性不会产生明显的影响； 3轴向和径向联合载荷作用下，径向载荷不大时球轴承振动的固有频率基本不变，但是可能引起变刚度激励的非线性振动，出现新的频峰，过大的径向载荷将使部分钢球脱离接触，使球轴承的振动和噪声呈现不稳定状态； 4润滑对球轴承的振动和噪声特性有重要的影响，良好的润滑对振动有明显的抑制作用，润滑不充分时，振动和噪声的水平会有明显增高，一定条件下还会激发接触副中的谐振，发出啸声，造成接触表面的伤害，无润滑干接触时，短时的运转就会损伤接触副表面，使振动和噪声迅速增大，并随时可能引发严重的磨损和卡滞失效；接触副润滑良好时，油膜的"刚化效应"使球轴承振动的固有频率有所提高，润滑剂中含有弥散性污浊时，振动的幅度总体升高，但弥散性污浊不会改变球轴承振动的频率特性；浙江大学博士学位论文：球轴承振动的研究 5低速时，球轴承振动的基本特征呈现不稳定状态，随着转速的提高，球轴承振动的频率特性趋于稳定，固有频率频峰升高； 6理论分析表明，干接触时钢球和滚道表面波纹度的某些谐波分量能激励球轴承的振动，振动的幅值与谐波幅值成正比，实际球轴承中钢球的分布不可能完全均匀，波纹度的激励作用会随时发生；润滑接触的分析表明，波纹度的任意谐波分量均能激励球轴承的振动； 7球轴承的几何和结构参数分析表明，球轴承尺寸越大，径向、轴向和角振动的固有频率越低；钢球中心圆直径增大，球轴承的径向和轴向振动的固有频率基本不变，角振动的固有频率有所上升，振动的幅频特性基本不变；径向游隙加大使球轴承的径向振动固有频率降低，轴向和角振动的固有频率有所升高，径向振动幅频特性的幅值升高，而轴向和角向降低；钢球的数量增多使球轴承振动的固有频率上升，幅频特性的幅值下降，径向振动的幅值下降最为明显；外圈沟曲率半径系数增大使球轴承径向振动的固有频率升高，轴向和角振动的固有频率降低，径向幅频特性基本不变，轴向和角向幅频特性幅值升高；内圈沟曲率半径系数增大使径向、轴向和角振动固有频率均下降，振动幅频特性的幅值均有升高； 8试验对比表明，传感器采用探针式安装时，由于探针接触副接触特性的影响，钡(量得到的球轴承振动信号有失真，采用专门设计和制作的试验球轴承，以固定式安装加速度计，首次测量得到了球轴承振动的真实信号，通过对振动信号的分析，验证了球轴承振动的理论模型； 9)基于时间序列分析的AR模型适用于大样本球轴承振动信号的分析，以样本长度的均方根值作定阶上界，FPE做判阶准则，给出的AR谱光滑，频率分辨率高，是球轴承振动分析的简便而可靠的手段； 10以时频域分析的小波包变换分析球轴承异音信号能够比较好地定位和聚焦异音发生的时间，时间间隔，频率范围，同样是球轴承振动分析的可靠的手段，可用作球轴承故障诊断技术。

David · the Baker Chinese mho is born: On May 2, 1975 height: 1.80m body weight: 71kg nationality: English Club: On imperial Madrid field position: The middle place joins time: In 2003 has stayed club: Graceful joint honor: 98/99 season Europe champion cup champion, the English ultra champion, the English foot total cup champion, Toyota cup champion Antonio · card Sa Nuo Robert · Carlos is born: On April 14, 1973 height: 1.68m body weight: 69kg nationality: Brazilian Club: On imperial Madrid field position: The fullback joins time: In 1996 has stayed club: Parr Melas, international Milan honor: The World Cup champion (Brazil in 2002) the European champion cup champion west the armor champion introduced: Robert · Carlos was considered is the world best left back, he most famous entered the ball is in the French cup captures French team's that in 1997 to enter the ball, he kicked the ball as soon as about 40 meters with his famous left leg flank which recorded looks like not not impossibly to enter, the ball changes suddenly right flank the French team human wall, and crossed French team goalkeeper Baht this to fly into the goal.

戴维·贝克汉姆出生：1975年5月2日身高：1.80m 体重：71kg 国籍：英格兰俱乐部：皇家马德里场上位置：中场加入的时间：2003年曾经呆过的俱乐部：曼联荣誉：98/99赛季欧洲冠军杯冠军、英超冠军、英格兰足总杯冠军、丰田杯冠军安东尼奥·卡萨诺罗伯特·卡洛斯出生：1973年4月14日身高：1.68m 体重：69kg 国籍：巴西俱乐部：皇家马德里场上位置：后卫加入的时间：1996年曾经呆过的俱乐部：帕尔梅拉斯、国际米兰荣誉：世界杯冠军(巴西2002年)欧洲冠军杯冠军西甲冠军简介：罗伯特·卡洛斯被认为是世界最好的左后卫，他最著名的入球是在1997年法国杯中攻入法国队的那个入球，他在40米开外用他著名的左脚的外侧踢出一记看起来不可能入的球，球在法国队人墙右侧突然转向，并越过法国队守门员巴特兹飞入了球门。

As the density of Al and Cu was quite difference,it was apt to delaminate and restrain the process of alloy by wet milling.The case was improved when dry milling,though it would be some reunite with the time of ball-milling prolonging.(2)The best technique parameters of high energy ball milling to prepare metastable powders of Cu-Al alloy were;the addition of Al powders was 1% in quality,the powders of Cu-Al were completely alloyed after high energy ball milling for 20 h.

1提出采用高能球磨制备Cu-Al合金粉的有效方法，认为由于Cu和Al的密度相差比较大，采用以液态酒精为过程控制剂的湿磨时，容易发生分层，抑制了合金化，采用干磨时，以硬脂酸为过程控制剂，虽然随球磨时间的延长会发生轻微的团聚，但能达到良好的合金化效果。

The result shows that the hydrogen storage properties increase remarkably after pure magnesium ball-milled with 10% TiFe(subscript 1-x)Cr (x=0, 0.3). Moreover, the chromium content also influences the hydrogen storage characteristics. Furthermore, the ball-milled composite of Mg+10%TiFe0.7Cr0.3 has the best hydrogen storage properties with hydrogenation capacity of 7.14% and dehydrogenation capacity of 6.91% at 613 K. In addition, the lower temperature of 493-573 K, the Cr-contained composite exhibits the best dehydrogenating kinetics.

研究结果表明：在纯Mg中添加质量分数为10%的TiFe(下标 1-x)Cr(x=0， 0.3)进行复合球磨，可以明显提高其吸放氢性能；在相同温度条件下，x=0.3的含铬复相合金具有最佳的吸放氢性能，其中在613 K下的吸氢容量为7.14%，放氢容量为6.91%；在493~573 K的较低温度下，含铬复相合金表现出更好的放氢动力学性能。

I just felt like I wanted to experience the playoffs. Even though I didn't play my best ball, I still got to understand the next level.

他说，我真的很想体验一下季后赛的感觉，虽然我没有打出我的最佳状态，但是我体会到了更高水平的比赛。

"Dark Nebula - or Extreme Labyrinth as I like to call it - is one of the best ball rollers out there."

&暗星云-或极端的迷宫，因为我喜欢把它称为-是最好的球滚子之一了。&

Q: The numbers suggest you are playing the best ball of your career so far.

目前的数据显示你处于职业生涯的颠峰，是吗

Both are highly skilled, and Odom is playing perhaps his best ball of his career.

他们俩技术都非常出色，而奥多姆可能正打出他职业生涯最好的表现。

Tracy McGrady is playing some of the best ball of his career.

麦蒂打出了职业生涯最为出色的一些比赛。

In the United States, chronic alcoholism and hepatitis C are the most common ones.

在美国，慢性酒精中毒，肝炎是最常见的。

If you have any questions, you can contact me anytime.

如果有任何问题，你可以随时联系我。