Study On The Mechanism Of Solid Tube Expansion Based On Axiomatic Design

Solid Expandable Tubular(SET)technology is an important process technology in oil drilling.Development of the mechanical model and parameter optimization entity pipe expansion and research the tools of expansion is the key to SET.Most of the SET's mechanical model is the use of rigid-plastic mechanics simplified model does not consider the work hardening nature of material,resulting in mechanical model has some shortcomings;structural design parameters for the expansion process involved the expansion tool optimization parameters are individually optimized to obtain a smaller expansion of load and did not analyze the whole expansion process,did not study the affect of relationship between the parameters;the existing expansion tools as well as certainly has design flaws.Therefore,this view of the above problems on the SET process,use the mechanical power hardening model,using the equivalent stress-strain and pull mechanics model plastic model expansion mechanics and finite element(FE)simulation,verify the correctness of the model;use of "zig-zag" mapping transformation building a relationship with the parameters and the goal of expansion process,using the independence of the axiom analyze the influence between parameters and decoupled it;Use sizing cone axiomatic design combined with analysis of the reasons for the coupling structure of existing adjustable cone analysis,namely the use of the principle of separation of inventive principles guide the completion of the expansion cone innovative design.The main content of the thesis mainly includes the following:1.Use power hardening model and a single curve hypothesis,consider connecting portion and the expansion area for sizing zone between the expanding force of the impact,the use of mechanical drawing theoretical model established plastic expansion mechanics model entities,and using FE calculations and experimental data to verify the correctness of the model.2.By analyzing the expansion process,to give overall function of the expansion process and the corresponding total structural parameters,then use the "zig-zag" mapping change to establish the expansion process of the function-parameter mapping,and then use mechanical model developed above to get the design matrix,using independent axiom analyzing the relationship between the structural parameters of the expansion process,and then use the ANSYS finite element simulation to optimize the important structural design parameters,obtained the range of structural parameters under certain optimal expansion.3.By analyzing the patented of existing adjustable cone obtained structural characteristics and establishment its design logic by obtained the feature information,then combined for sizing cone function-parameter analysis of the adjustable cone functional-structural analysis,now find the root cause design coupling of adjustable cone is that the expansion process to achieve functional coupling between the expansion and the seal produced,followed by using TRIZ theory to decouple,and obtain functional independence of the new adjustable expanding cone design.