Research Of The Cementing Technology Of The Shear Vortex Vibration In The Downhole

The shear vortex vibration cementing applies cementing fluid as power source, driving the downhole eccentric blade rotation and casing string rotate eccentrically, producing radial vibration pulse, reducing the viscosity of drilling fluid, improving the rheological property of drilling fluid and strengthening the flow pattern effect. It also reinforces the carrying capacity of the circulation, efficiently cleans the hole, effectively eliminates air bubbles in cement slurry, and improves the cementing paste interfacial bonding strength, thus improving the cementing quality.This paper analyses the change of the drilling fluid when flowing through the downhole eccentric leaf, the effect on cement slurry of the downhole cascade eccentric vibration,downhole annular casing string vibration, downhole vibration and the replacement efficiency mechanism of annular flow. It also establishes the models of downhole blade rotating force and annular casing string vibration which suit the downhole complicated conditions.An indoor simulation evaluation of downhole shear vortex vibration cementing technology is made to measure the vibration parameters of different displacement and fluid density and the influence of vibration frequency on the fluid and cement slurry performance. Based on the evaluation, the author optimizes the design of the generator structure of the downhole shear vortex vibration, screens out the best structure parameters and designs the best generator which can be applied in the field.50wells have been tested with this and concluded weel.