环境介质及表面结构对夹持块摩擦性能的影响

连续管注入头夹持块在使用过程中表面会粘附钻井液、原油和石蜡等井下介质,从而对夹持块摩擦性能造成影响,另外夹持块表面结构形式的不同也会对摩擦性能造成影响。为此,用自行设计的测试设备对夹持块与连续管在不同条件下的当量摩擦因数进行测试及分析。分析结果表明,对于光面夹持块,在无介质条件下,其当量摩擦因数为0.443;原油对当量摩擦因数影响较小,石蜡对夹持块摩擦性能影响最大,其当量摩擦因数下降至0.074;对于无介质环境下的表面刻槽夹持块,齿宽和槽宽越窄,夹持性能越好;在石蜡环境下,23型夹持块有效减少了接触面上的石蜡,摩擦性能大幅度提高。

Effects of Environmental Medium and Surface Structure on the Friction Performance of CT Clamping Block

There are adhesion downhole media on the CT clamping block,such as slurry,crude oil and paraffin in its application process.As a result,the friction performance of the block will be affected.Moreover,the difference in the surface structure of the block will also have effect on its friction performance.Therefore,the self-designed testing apparatus was used to test and analyze the equivalent friction coefficient of the block and CT in different conditions.The findings show that as for smooth surface clamping block,the equivalent coefficient is 0.443 when there is no medium.Crude oil has slight effect on the coefficient.Paraffin has the maximum effect on the friction performance of the block and the coefficient decreases to 0.074.As for the medium-free clamping block with surface notch groove,the narrower the tooth width and groove width,the higher the clamping performance.In the environment of paraffin Model 23 clamping block effectively reduces the paraffin on the contact surface and the friction performance increases remarkably.