【振动分析领域的技术术语】
https://ludeca.com/blog/vibration-analysis/3959/glossary-of-vibration-analysis-terms/
英文
he field of vibration analysis, there is an abundance of technical terms. We provide definitions for some of these terms that you might hear from an engineer or technician as well as read in reports and might need further clarification. We welcome you to check out our glossary of terms relating to vibration analysis, and hope you find it valuable!
- Average – In vibration analysis, an average usually refers to the process whereby the vibration software will, after converting waveforms into spectrums via FFT, add the resultant spectrums together and then divide by the number of spectrums added together. The result is an “averaged spectrum”.
- Band –– A band is simply a range of frequencies e.g. A band from 0 Hz, to and including 5 Hz, is a band that is 5 Hz wide.
- Band Pass Filter – A filter that blocks all data above and below its defined band.
- Condition Monitoring –– The use of specialized equipment to deduce the actual condition of the equipment as pertains to its fitness for continued use. Condition monitoring is the foundation of Predictive Maintenance and the two terms are sometimes used interchangeably.
- Cycles per minute (CPM) –– In vibration analysis, cycles per minute refer to the number of vibratory cycles that occur in one minute of time. Cycles per minute is a quantity of frequency.
- Cycles per second (CPS) –– In vibration analysis, cycles per second refer to the number of vibratory cycles that occur in one second of time. Cycles per second is a quantity of frequency.
- Enveloping – Enveloping, also known as envelope de-modulation, is a data processing technique whereby a spectrum is created from a demodulated or filtered waveform.
- FFT –– Fast Fourier Transform (FFT) is a mathematical process that transforms a waveform into the components of its frequency spectrum.
- Fmax –– Fmax stands for “maximum frequency”. It is the high-frequency boundary for a set of data.
- Fmin –– Fmin stands for “minimum frequency”. It is the low-frequency boundary for a set of data.
- Frequency Markers –- These are visible marks that can be overlaid on a spectrum at specific frequencies to help identify likely machinery problems.
- Hertz (Hz) –– The same as “cycles per second”.
- High Pass Filter (HP) –– This filter blocks all data below it and only allows the data that is higher to “pass” and be recorded. It determines the “low-frequency cutoff” or Fmin.
- LOR –– LOR stands for “Lines of Resolution”. It is the number of digital bins of amplitude information a spectrum will be constructed from.
- Low Pass Filter (LP) –– This filter blocks all data above it and only allows the data that is lower to “pass” and be recorded. It determines the “high-frequency cutoff” or Fmax.
- Negative Averaging – A procedure whereby, having previously taken a reading, a second reading is taken and all data in the first reading that matches data in the second reading is subtracted.
- The % Overlap: –- The % overlap is the amount several otherwise sequential waveforms, being sampled and averaged into a spectrum, will “overlap one upon the other” as they are being sampled.
- Peak-to-Peak –– The measure of vibration amplitude in a waveform, from the negative peak to the positive peak.
- Unbalance –– A measure that quantifies how much the rotor mass centerline is displaced from the centerline of rotation.
- Waveform –– In vibration analysis, a waveform is a display of vibratory energy over time.
在振动分析领域有大量的技术术语。其中一些术语的定义如下：
术语表 glossary-of-vibration-analysis-terms
- 平均值：在振动分析中，平均值通常是指振动软件通过FFT将波形转换成频谱后，将得到的频谱相加，然后除以相加的频谱数的过程。结果是一个“平均频谱”。
- 频带：频带只是一个频率范围，例如，从0 Hz到并包括5 Hz的频带是5 Hz宽的频带。
- 带通滤波器：阻止所有高于其之上和低于其定义的频带。
- 状态监测——使用专门的设备来推断设备的实际状态，使其适合继续使用。状态监测是预测性维护的基础，这两个术语有时可以互换使用。
- 转每分(CPM)：每分钟转数。
- 转每秒(CPS)：每秒钟转数。
- 包络Enveloping：也被称为包络解调，是一种数据处理技术，通过这种技术可以从解调或滤波的波形中创建频谱。
- FFT：快速傅里叶变换(FFT)是一个数学过程，将波形转换为其频谱的组成部分。
- Fmax：Fmax代表“最大频率”。它是一组数据的高频边界。
- Fmin：Fmin代表“最小频率”。它是一组数据的低频边界。
- 频率标记Frequency Markers：这些可见的标记可以覆盖在特定频率的频谱上，以帮助识别可能的机械问题。
- 赫兹 Hertz(缩写为Hz)：与“转/秒”相同。
- 高通滤波器 (HP, High Pass Filter)：这个Filter阻断低于它的所有数据，只允许高于它的数据“通过”并被记录。它决定了“低频截止”或Fmin。
- LOR：LOR代表“Lines of Resolution分辨率线”。它是用来构造频谱的幅度信息的数字箱的数目。
- 低通滤波器(LP, Low Pass Filter)：该滤波器阻塞其上方的所有数据，只允许较低的数据“通过”并被记录。它决定了“高频截止”或Fmax。
- 负平均Negative Averaging：一种程序，在先前的读数中，进行第二次读数，并减去第一次读数中与第二次读数中数据匹配的所有数据。
- 重叠的百分比:重叠的百分比是数个其他顺序的波形，被采样和平均成一个频谱，将“重叠在另一个上”，因为他们正在被采样。
- 峰峰值：测量波形中的振动幅度，从负峰到正峰。
- 不平衡：量化转子质量中心线偏离旋转中心线的程度。
- 波形Waveform：在振动分析中，波形是一段时间内振动能量的显示。
