风电机组法兰用摩擦垫片的摩擦系数实验研究

Experimental study on friction coefficient of friction gaskets for the flanges of wind turbine

提高主轴与齿轮箱法兰联接面的静摩擦系数,可以间接实现主轴与齿轮箱法兰联接面的紧凑设计,实现风电机组的轻量化。针对风电机组传动系统紧凑化和轻量化设计的问题,对风电机组法兰用摩擦垫片的摩擦系数进行了实验研究。首先,分析了主轴与齿轮箱法兰联接面摩擦系数对其传扭能力和减重降本的影响;然后,采用主轴与齿轮箱法兰材料球墨铸铁QT400-18AL和QT700-2做了实验试样,研究了该摩擦垫片用于两种试样间时的静摩擦系数;最后,提出了一种采用拉、扭组合试验机加载准静态扭转和压缩载荷来测试静摩擦系数的方法,并基于该方法对结合面平均接触压强为50 MPa、100 MPa、125 MPa、150 MPa时摩擦垫片的静摩擦系数进行了研究。研究结果表明:当结合面平均接触压强大于50 MPa时,静摩擦系数平均值为0.667,标准差为0.023;相比未使用摩擦垫片时,使用摩擦垫片时可将其静摩擦系数提高约1倍;摩擦垫片重复使用时,静摩擦系数呈下降趋势;因此,在实际风电工程中,应采取相关措施,保证摩擦垫片重复使用时结合面静摩擦系数不会过低,以保证其联接的可靠性。

Improving the static friction coefficient of the connecting surface between the main shaft and the gearbox flange can indirectly realize the compact design of the connecting surface between the main shaft and the gearbox flange,and realize the lightweight of the wind turbine.Aiming at the problems of compact and lightweight design of wind turbine transmission system,the friction coefficient of the friction gasket used in connection flange on the wind turbine was experimentally studied.Firstly,the influence of friction coefficient of the surface of connection flange between spindle and gearbox on the ability to pass a twist and lose weight to reduce costs was analyzed.Then,the nodular cast iron QT400-18Al and QT700-2 for wind turbine spindle and gearbox flange were selected as samples to study the static friction coefficient between the two kinds of specimens.Finally,a method was proposed to measure the static friction coefficient based on the quasi-static torsional and compressive loads of a tension-torsion combined testing machine,and the static friction coefficients of friction gaskets at the average contact pressures of 50 MPa,100 MPa,125 MPa and 150 MPa were studied respectively.The research results show that the mean value and standard deviation of static friction coefficients measured in the experiment are 0.667 and 0.023 respectively,when the average contact pressure of the bonding surface is greater than 50 MPa.The static friction coefficient can be increased by about one time with the use of friction gasket.When the friction gasket is reused,the static friction coefficient decreases.In the actual wind power engineering,relevant measures should be taken to ensure that the static friction coefficient of the joint surface will not be too low when the friction gasket is reused,so as not to affect the reliability of the joint.