免费工程工具 #044
轴承修正额定寿命 Lnm 计算器
计算修正额定寿命 Lnm 采用 ISO 281:2007 可靠性系数和ISO 值，该值根据实际轴承和运行条件确定。
成果
适用性警告： C/P 低于 2。公开的制造商指南指出，在此范围内常规额定寿命理论不再完全适用。此处显示数学计算结果，但需要轴承专用指南和更完整的分析。
基本额定寿命10
根据 ISO 281 标准，基本额定寿命（以百万转为单位）为：
- C — 基本动态载荷额定值（kN）
- P — 等效动态轴承载荷 (kN)
- p — 寿命指数：滚珠轴承为 3，滚子轴承为 10/3
修正额定寿命 Lnm
ISO 修正额定寿命采用可靠性系数1 以及与工况相关的系数ISO:
- a1 — 可靠性寿命修正系数（ISO 281:2007 中 90% 时为 1.00，99% 时为 0.25）
- aISO —润滑、污染和疲劳载荷极限的寿命修正系数
转换为小时
可靠性因子1
| 可靠性（%） | a1 | Ln 符号 |
|---|---|---|
| 90 | 1.00 | L10m |
| 95 | 0.64 | L5m |
| 96 | 0.55 | L4m |
| 97 | 0.47 | L3m |
| 98 | 0.37 | L2m |
| 99 | 0.25 | L1m |
实例
已知： C = 52.7 kN，P = 10 kN，n = 1500 RPM，a1 = 1.0，aISO = 1.0
L10 = (52.7 / 10)3 = 1.4636亿转
L10小时 = 146.36 × 106 / (60 × 1500) = 1626小时
L10m = 1.0 × 1.0 × 1,626 = 1626小时
⚠️ 范围： 修正额定寿命是统计疲劳额定值，并非保证的使用寿命。ISO 281 未涵盖磨损、腐蚀或电蚀。a 的数值ISO 高于 50 时，此处不予接受，因为公开的制造商指南指出，对于这一简化计算，此类数值没有意义。
ISO 281 expresses modified rating life as Lnm = a₁ × aISO × L₁₀. The subscript n is failure probability in percent.
It is a statistical fatigue rating under the standard’s conditions, not a guarantee of service life.
L10 is basic rating life at 90% reliability under the conventional conditions stated by ISO 281. Lnm applies the reliability factor a₁ and the condition-dependent aISO factor.
Wear, corrosion and electrical erosion are outside ISO 281 rating-life scope.
Use the ISO 281:2007 factor for the required reliability:
- 90%: 1.00
- 95%: 0.64
- 96%: 0.55
- 97%: 0.47
- 98%: 0.37
- 99%: 0.25
Higher required reliability gives a lower rating life.
The life exponent p is 3 for ball bearings and 10/3 for roller bearings. It appears in the basic rating life formula L10 = (C/P)p and reflects the different contact geometry: point contact for balls, line contact for rollers.
Do not choose aISO from a generic clean or dirty label. Determine it with the ISO 281 method or verified bearing-manufacturer software or diagrams for the exact bearing and operating conditions.
The determination uses bearing-specific and operating inputs such as viscosity ratio, contamination factor, fatigue load limit and equivalent load. This calculator only applies the supplied value.
本页所述的操作流程由 Vibromera 团队使用 Balanset-1A（一款用于现场转子平衡的便携式双通道动平衡仪及振动分析仪）开发并经过实地测试。
专业现场动平衡仪和振动分析仪。现场监测轴承状态。已在50多个国家使用。
