Study On Constant Flow Blanking Plug For Layered Water Injection In Oil Fields

As an important strategic material, oil has been paid attention more and more by every country, now it is a focus about highly efficient oil recovery. Especially, our country is short of energy, and most of oil fields are in the later period of oil recovery, so it is in urgent need about highly efficient oil recovery. Layered and quantitative water injection is a widely used technology in oil field, and blanking plug is an important part in this technology, so it is important to develop good blanking plugs.This thesis develops a kind of constant flow blanking plug with simple structure, long useful time and low costs. By means of comparison and analysis, the blanking plug uses mechanical structure, and slide valve– spring style is used as a basic structure. The bond graph model of blanking plug is built based on foundation of hydromechanics, static and dynamic simulations are also carried out by using software 20-SIM, so the basic property of blanking plug is found, then the values of structural parameters are decided by parameters scanning simulation of different parameters value.Considering about seriation, adjustability, reliability and working quality, structure of blanking plug is designed, it mainly contain: designing motionless damping hole as separated structure; adjusting the precompression of spring with micrometric adjusting screw; reducing the hydraulic chucking force by tooling pressure equalizing groove on the spool face and using self-centering unit between spring and spool. The experiments make known that the blanking plug can basically make the flow rate constant in the process of water injection.Then the structure is improved in following two sides: on one hand, the ordinary motionless damping hole is changed to compensating style, it has two patterns, serial type and parallel type, could ensure the flow coefficient unchangeable; on the other hand, after revising the efflux angle, a new kind of structure is designed to counteract the hydrodynamic force with dynamic analysis and flow field simulation, this structure make the blanking plug more close to theoretical mode.