横向振动对水平井眼中钻柱摩阻的影响研究

激振力的幅值和频率是影响横向振动类减摩阻工具性能的主要参数,利用自行研制的旋转激励载荷作用下摩擦力测试试验装置,研究了激振力的幅值和频率对钢-石板平面摩擦副摩擦系数的影响规律.试验结果发现,在激振频率为5,10和20 Hz条件下,与未施加激振力时的摩擦系数相比,当激振力增加到34.2 N时,钢-石板平面摩擦副的摩擦系数分别减小21.6%,29.0%及34.4%;在激振力为11.4,22.8和34.2 N条件下,与未施加激振力时的摩擦系数相比,当激振频率增加到30 Hz时,钢-石板平面摩擦副的摩擦系数分别减小22.8%、27.4%及39.0%.研究结果表明:在相同激振频率下,钢-石板平面摩擦副的摩擦系数与激振力幅值呈线性负相关;在相同激振力幅值下,钢-石板平面摩擦副的摩擦系数与激振频率呈对数负相关. 

The Impact of Lateral Vibration on Friction of Drill String in Horizontal Wells

The amplitude and frequency of the exciting force are main factors which impact on performance of the lateral vibrating friction-reducing tools. Through measuring friction under the load of rotary exciting force with the self-developed testing unit, the impact of amplitude and frequency of the exciting force on the friction coefficient of plane friction pairs between steel and rock plate was diagnosed. The results show that friction coefficients reduced by 21.6%, 29.0% and 34.4% respectively when the exciting force increased from zero to 34.2 N at the frequency of 5, 10 and 20 Hz, and by 22.8%, 27.4% and 39.0% respectively, when the exciting frequency increased from zero to 30 Hz at the exciting force of 11.4, 22.8 and 34.2 N respectively. The study indicates that the friction coefficient of plane friction pairs between steel and rock plate has a negative linear relationship with the amplitude of the exciting force at the same exciting frequency, and a negative logarithmic relationship with the exciting frequency at the same exciting force.