EVALUATION OF DESIGN PARAMETERS OF ORIENTED ASSEMBLIES TO PROVIDE THEIR DESCENT IN THE DIRECTIONAL WELL

Abstract

This scientific publication proposes a new method for assessing the impact of technical and technological parameters of oriented slick assemblies and assemblies with one stabilizer on their passage in the directional well. The analysis of possible cases of contact of elements of oriented assemblies with well walls is carried out. According to the results of this analysis a number of mathematical models of oriented bottom hole assemblies for calculating the power parameters of the interaction of their elements with the well walls during descent into a well with an arbitrary zenith angle are developed. Using the developed mathematical models, a study of the influence of the design parameters of the oriented assemblies on their axial passage in the wellbore to prevent of their jamming has been carried out. 
 The calculated mathematical models of the assemblies are based on the method of differential equations of second order. The research is focused on obtaining the value of the conditional diameter of the assembly, taking into account its deformation from the effect of the transverse component of the weight. On the example of oriented slick assemblies and those with one stabilizers on the basis of the mud motor, a calculation of the value of the conditional diameter of the assembly and the diameter of the stabilizer from the condition of observing the optimal diameter of the assembly has been performed.
 According to the results of analytical studies on the example of slick assemblies and assemblies with one stabilizer, using the developed approach, the authors have established the following: conditions for their free passage in the wellbore along the entire range of the zenith angle change; the necessity to control the passage and axial displacement of the oriented assemblies in the performance of tripping operations; the dependency of the value of the "conditional" diameter of the oriented assembly on the position of the bent angle of the toolface to the well trajectory. In particular, in the upper position of the bent angle of the toolface, the "conditional" diameter of the assembly is smaller than in the lower position, and an increase of the zenith angle of the wellbore leads to a decrease in the "conditional" diameter of the oriented assembly due to its laying under the action of the transverse component of the weight.