如何解决风电齿轮箱研制中检验修形效果的难点？How to solve the difficulties of modification evaluation during the design of a wind turbine gearbox

1.  通过应变片测试法来得到齿根部位的弯曲应力。

2.  使用通用型小尺寸的应变片。

3.  Micro-Measurements 的防护涂层M-Coat A提供优异的防潮和防化学侵蚀性能。

当然布点方式也很有技巧性。直齿轮齿根承受一个水平面弯曲正应力和垂直切应力，两个应力都垂直与齿向；而斜齿轮齿根除承受与直齿轮相同方向的两个应力外，还承受一个铅垂面内的平行于齿向的切应力，但这个铅垂面内的切应力并不大。一般情况下，可以用直齿轮的疲劳试验结果做参考进行斜齿轮的疲劳强度设计。由于疲劳断裂主要是由于弯曲正应力引起，因此除一些特殊情况外可以只校核弯曲正应力。鉴于此，通过贴片测量单向应力（弯曲正应力）用于评价弯曲强度从某种程度上是适合的。至少在齿根两个端部、中部3个地方贴应变片，这样可以观察弯曲应力沿齿向的变动情况。

1. By strain measuring method to get the tooth root bending stress site.

2. The use of general-purpose small strain gages.

3. Protective Coating M-Coat A

   Stress distribution in a spur gear is unique. The spur gears are subjected to a horizontal bending normal stress and vertical shear stress, both of which are perpendicular to the tooth direction. The helical gear teeth are subjected to two stresses in the same direction as the spur gears, but also in a vertical plane in the tooth. The shear stress is not large. Under normal circumstances, you can use the spur gear fatigue test results for reference to the helical gear fatigue strength design. Since the fatigue fracture is mainly due to the bending stress, then in addition to some special circumstances, it is only necessary to check the bending normal stress. In view of this, it is appropriate to measure the bending strength by some means to measure the uniaxial stress (bending normal stress).  The bending strain along the length of the tooth is measured by the application of three strain gages, one on each end of the tooth, and one in the middle.