适当的平衡是设计和制造高速齿轮单元中的关键键之一

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不平衡是高速齿轮机组严重振动的最常见原因。出现时,振动导致轴承、齿和密封损坏。不幸的是,没有实际的方法来联系齿轮的平衡与振动。即使是完美加工的实心圆盘也会由于材料的非均匀性或由于轴和齿轮之间的间隙造成的偏心而产生不平衡的旋转。材料问题导致偏离几何中心。轴间隙使几何中心远离旋转轴。许多这种先进的驱动被用于发电,1990年代的一系列试验证明,不平衡和由此产生的振动会造成巨大的能量损失。15- 25%的损失被记录在案。当齿轮两端有重点,且质量中心线与旋转中心线相交时,只有通过转动齿轮并测量不平衡合力或振动才能检测不平衡。高速运转时,所有齿轮和轴应保持平衡。 Balancing involves both high and low speed. Low-speed balancing ensures that neither the machine nor the gears are affected by vibration during the high-speed balancing process. Typically, low-speed balancing takes place between 100 and 1,000 rpm. The stiffness of the high-speed balancing machine may differ from the field installation, and in turn affect the critical speeds that were observed. High-speed balancing gives superior results and is a requirement for many drives, but it is time consuming and expensive.

已经在平衡的主题上产生了几项标准。主要是,在齿轮领域,API标准的使用已经存在,例如机械设备的API CRE小组委员会(1999年11月22日,API-613和617)。API 613-FEB。2003年要求所有齿轮都是多平面动态平衡的。当有一个键槽时,它将填充完全加冠的半键。记录了所有半键的重量。ISO 8821中完全描述了“半关键序列”。API 617导致剩余的长距离转子重量的<10%。最大残余不平衡由轴静态加载的四倍计算最大连续RPM的磅数。API-684是“API标准段落的教程,其中包含转子动态和平衡”。在大多数情况下,这些标准基于实际的实地经验。 ISO-1940-1 defines balance quality and determination of residual unbalance, and ISO 13691 is for High-Speed Special Purpose Gear Units. Both standards are less conservative than API. ISO 11342 second editions includes methods and criteria for the mechanical balancing of flexible rotors. The U.S. Navy MIL-STD-167 was developed to make it more difficult for sonar operators to detect machinery vibrations, and thereby track naval vessels. The calculations are based on rotors operating above 1,000 rpm. Lloyd’s Register for the Classification of Ships similarly requires balancing for all gears running in excess of 1,000 rpm with minor exceptions. AGMA standard 6011-1/03 for high speed helical gear units with one stage at speeds > 4,000 rpm requires all gear rotating elements to be multi-plane dynamically balanced and does not deviate from similar standard requirements. Three separate unbalanced tolerance charts have been established for commercial gear sets, military gear drives, and precision drive systems.

必须最近在其制造商设置的精度公差范围内校准平衡机。通常,平衡机被归类为柔软或硬轴承。在软轴承机中,转子安装在柔性支撑系统上。与转子组合时的自然频率低于平衡速度。机器也必须足够敏感,以提供可靠和可重复的不平衡数据。在轴承支架上测量振动幅度或速度。硬轴承机器通常采用较大且较重的转子。因为支撑系统是刚性的,所以应变计换能器用于测量不平衡力。ISO 2953是平衡机校准和性能的标准。