Study On The Injector Of Coiled Tubing Unit Based On Virtual Prototype

Coiled tubing has become an increasingly improved new technology in oil-gasexploration field. With its extensive adaptability, efficiency logging and drilling, outstandinglow cost in working, low pollution to the environment and other characteristics, it has becomeone of the important directions of technical developments in oil exploitation. But its physicalprototype has long production period and high production cost, the virtual prototypetechnology will greatly reduce the product development cycle, reduce unnecessary mistakesin production, and provide visual design platform for products at the same time. So the studyon the injector of coiled tubing unit based on virtual prototype has an important theoreticalguidance and economic value.By analyzing to the injector of coiled tubing unit，the statics analysis model of the tubinginstability problem and the dynamic load model of the injector are built, which give a theorybasis for the structure design and selection of the device and structural design. According tothe expected function of the injector, the virtual prototype of the injector is designed. Thevirtual prototype of injector is simulated in different working conditions by using RecurDynwhich is a Multi-body dynamics software.The virtual prototype of the injector works well in different working conditions, so it canbe used to study and simulate some performance of the coiled tubing unit instead of physicalprototype. The results show that the bushing tension of injector changes as a cyclical byresearching the tensioner force in different conditions. It is found that the best casing offspeed is0.1m/s and the best lifting speed is0.3m/s.The load curve that the relationship with the bushing tension, the friction coefficients, thecasing off speed, the lifting speed and lifting load are presented. For example, as in certainfriction coefficient conditions, the curve of the relationship with clamping force and ascensionload, as variable coefficient, the curve of the relationship with friction clamping force andascension load relationship, the curve of the relationship with coiled tubing down/liftingspeed and ascension load, and etc. The results show that as in certain friction coefficientconditions, ascension has nothing to do with load speed, speed of tubing has a linearproportional relationship with the power output of the motor. As in certain lifting speedconditions, the friction coefficient of slips and coiled tubing has a linear proportionalrelationship with the bearing capacity of the injector and the power output of the motor. Theresearch results give guidance parameters to the further optimization design that control loadand oil cylinder, control drive motor of the coiled tubing unit.