Study On Structure Of Coiled Tubing Downhole Cutting Equipment In Oil Field

For tubing,casing string sticking accidents occurred during completing wells, releasing stuck was used gernerally, if stuck release method can not solve the problem, tucked up by moving around and so on, way of tube cutting must be used to draw back the tube out of the well. Now oilfields are some of minor diameter wells and of highly deviated, however ordinary cutting equipment are difficult to resolve, easy to appear the phenomenon of not flat and the problem of the equipment is difficult to transport to the designated location. This design is mainly used for those wells which are of small diameter and are difficult to reach the well, with a high degree of automation, high efficiency, the cutting section being flat and easy to put forward the well, this thesis mainly includes the following contents:First of all, this thesis introduced the structural design of the downhole oil well tubing cutting equipment, and UG model diagram and engineering drawings. It is easy to know the movement and the assembly relation between the equipment components, equipment related to cooperate the use of equipment and equipment into the well, work and out of the well.Secondly, by modal analysis of axis cutting equipment shell using ABAQUS finite element simulation software, each period of natural frequency was analyzed in order to prevent cutter from resonance in the process of rotating, which finally would affect the stability of cutting. Then the stress and strain analysis was carried out on the cutting head, pushing tool rod and enclosure, to ensure that its tensile strength, rigidity, deformation displacement in the cutting process and the use of cutting equipment safety and life.Next, the study of the optimal design of pushing tool rod, such as increasing the thickness of the tool holder base and rounded corners between the base and push rod. Reducing the deformation displacement, ensures the cutting equipment to cut smoothly.Finally, downhole positioning problem of cutting equipment was introduced in detail. Martin decker generation depth sensor will convey level signal to the single chip microcomputer which could count and operate. LCD device displays the information of depth, speed of upward and downward movement of equipment. This facilitate the operation for operators up the well and carrying on field test to verify.