性摩擦

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。

Bloyce A, Dong H. Comparative evaluation of treatment for wear protection of Ti-6Al-5V. In:Proc 8th Word conf On Titanium, Birmingham, 19953 Fisher J, Dowson D. Tribology of total artificail jionts. Proc Instn Mech Engers, 1991; 205H:73

2化学镀Ni-P-PTFE复合层具有优异的耐磨性和减摩性，大大改善了Ti-6Al-4V摩擦磨损性能，使Ti-6Al-4V应用于在人工关节以及其它磨损较大的部位成为功效可能。

This goods can improve the heat-resistant and climate aging resistance of friction material,improve the service life.

该型号产品能够提高摩擦材料的耐热性和耐候性，提高使用寿命。

The main products are: Hammer, thermal conductivity detector, permeameter, contraction of the expansion device, hand-held strain gauge, waterproof material detector, low-bending device, slag ball content in separators, heat load tester, performance test combustion furnace, a variety of thickness, thermal expansion of graphite electrode NG, coal strength meter, electric tamping device, hydrophobicity tester, mineral wool density meter, concrete drilling sampling machines, sawing machines, removed machine, setstube machine, hydraulic bending machine, impervious tester, determination of heat resistance, heating telescopic measuring device, an extension device, penetration tester, small meter, viscometer, drying time tester, pencil hardness tester, pendulum hardness, the adhesion tester, film zoned grid, and resistant to scrubbing detector, solvent resistance detector, wearable device, flat grinding device, wear-resistant coating shakeout device, staining resistance tester, impact tester , piercing instrument, instrument bending film, film coating, and sanding machines, cone-shaped grinding, high-speed dispersion machine, three roller grinder, Scratch tester, indentation tester, gloss Miriam, white tester, fresh video of Miriam, Miriam reflectivity, iron cobalt colorimeter, paint density cup, crack resistance testing apparatus, leveling device, flow hanging device, visual color box, the minimum temperature detector into a grinding, low temperature brittleness tester, visual color boxes, electronic pull machine, Mooney Viscometer, vulcanizing device, the proportion of direct-reading, the cold compression tester, heritage wearable device, Heritage scratch device, the friction coefficient detector, coating Detect zoned grid plate , coating resistance tester, such as burning a variety of test equipment.

主要产品有：回弹仪、导热系数测定仪、渗透仪、收缩膨胀仪、手持应变仪、防水材料检测仪、低温弯折仪、渣球含量分离器、热荷重试验仪、燃烧性能试验炉、各种测厚仪、石墨电极热膨胀仪、煤强度测定仪、电动击实仪、憎水性测试仪、矿棉容重测定仪、混凝土钻孔取样机、锯切机、磨平机、套丝切管机、液压弯管机、不透水试验仪、耐热性测定具、加热伸缩测定器、延伸仪、针入度仪、细度计、粘度计、干燥时间试验器、铅笔硬度计、摆式硬度计、附着力测试仪、漆膜划格器、耐洗刷测定仪、耐溶剂测定仪、耐磨仪、平磨仪、涂层落砂耐磨仪、耐沾污测试仪、冲击试验仪、穿孔仪、漆膜弯曲仪、涂膜涂布器、砂磨机、锥形磨、高速分散机、三滚研磨机、划痕试验仪、压痕试验仪、光泽仪、白度仪、鲜映性仪、反射率仪、铁钴比色计、涂料密度杯、抗裂性试验仪、流平仪、流挂仪、目视比色箱、最低成磨温度测定仪、低温脆性试验仪、目视比色箱、电子拉力机、门尼粘度仪、硫化仪、直读比重计、压缩耐寒试验仪、文物耐磨仪、文物划痕仪、摩擦系数测定仪、涂层检测划格板、涂层耐燃烧试验仪等多种试验仪器。

D. Use method of condom sexual intercourse: Condom of male Dai Yong has sexual intercourse, can ease phallic friction, reduce the sensitivity of male sex excitement thereby, extend coital time, avoid premature ejaculation.

D。采用避孕套性交法：男性戴用避孕套进行性交，可以减轻阴茎的摩擦，从而降低男性性兴奋的敏感性，延长性交时间，避免早泄。

The relationship between the spinnability of easy eationic dyeable PET fiber and the performance of finishes was studied from the aspects of friction property and antistatic behavior.

从纺织过程中的摩擦特性、抗静电性等方面分析了阳离子可染聚酯纤维的可纺性与油剂性能之间的关系。

The relationship between spinnability of easy cationic dyeable PET staple fiber and property of oiling agent was discussed based on its anti-static characteristic, nature of friction, etc.

从阳离子可染聚酯短纤维在纺织过程中的摩擦特性、抗静电性等几方面探讨了纤维的可纺性与油剂性能之间的关系。

The PCBN cutting tool, with many advantages such as good wear resistance, thermal and chemical stability, low friction factor and so on, has incomparable superiority when hard machining ferreous materials, instead of grinding, is becoming a new kind of finish machining way.

PCBN刀具具有硬度高、耐磨性好、热稳定性和化学稳定性好，导热性良好以及摩擦系数低等优点，在硬态加工铁系材料时具有无可比拟的优越性，正逐步取代磨削加工而成为一种新的精加工途径。

POY and FDY oiling agent s on wetting, friction, heat-resisting, attrition-resisting properties, etc.

比较了国产和进口的适用于涤纶高速纺丝的预取向丝油剂及一步法牵伸丝油剂的润湿、摩擦、耐热、耐磨等性能，经实际生产应用证明二者的可纺性、上浆性、染色率基本相同。

The effects of the mates with different machining technology and surface treatments on wear resistance were examined.

同时还考察了不同加工工艺和表面处理方法的配合件对其耐磨性的影响，测定了在油润滑和干摩擦下的摩擦系数。

The concept of equivalent rotationally rigidity is offered and the formula of rotationally rigidity is obtained.

主要做了如下几个方面的工作：对伸臂位于顶部的单层框架—筒体模型进行分析，提出了等效转动约束的概念和转动约束刚度的表达式。

Male cats normally do not need aftercare with the exception of the night after the anesthetic.

男猫通常不需要善后除了晚上的麻醉。