Research On The Key Technologies Of Continuous Pipe Laying Method

Direct pipe laying with pipe pusher is the most ideal trenchless construction method at present,which has been widely used in various complex strata crossing,with high guiding accuracy and low risk,and has the technical advantages of simultaneous reaming drilling and pipeline laying.With the increasing demand for large diameter and long-distance transnational oil and gas pipeline construction,it is found in the field operation of direct pipe laying method that the intermittent operation of pipe pusher may produce pipeline rebound,and the intermittent operation has problems such as pipeline laying halt and equipment start-stop force,which leads to a long construction period,construction cost and accident increase.A continuous pipe laying method is proposed to solve the technical problems of intermittent operation and avoid the risk of pipeline rebound caused by pipeline stopper by the continuous pipe laying method.The double pipe mechanism is adopted to work at the same time to overcome the construction problem that the traditional trenchless equipment is faced with large start-stop force when it stops and runs again in long-distance pipeline construction.The continuous pipe laying method is based on the traditional pipe pushing machine to innovate the pipe holding mechanism of pipe-laying equipment to solve the problem of insufficient holding force.The vulcanized rubber tooth texture of slips is selected and redesigned to prevent the phenomenon of sliding pipe,and the power mechanism is designed to make it have a large thrust to meet the long-distance pipeline construction.Abaqus finite element analysis software was used to carry out multi-body system simulation analysis on the pipe-laying mechanism.Based on the dynamic data obtained from the simulation results,structural optimization was carried out on the existing problems or deficiencies of each component.After repeated simulation optimization,the design of the new pipe-laying machine’s pipe-holding mechanism met the practical application effect.After overcoming the start-stop force,the structural strength of each component is still safe and reliable when a uniform push-pull pipeline operation is realized.At the same time,the vulcanized rubber texture selection on the inner surface of the slips was simulated and analyzed.The analysis results showed that the parallel texture of vulcanized rubber teeth is the optimal selection scheme at present.Appropriately increasing the number of teeth can not only ensure the actual contact area in the process of pushing and pulling the holding pipe but also effectively improve the holding friction of the pipe.The hydraulic system of the power mechanism of the new pipe-laying machine is designed.Based on the parameters of the push-pull hydraulic system of the power mechanism,the dynamic characteristics of the synchronous hydraulic system of the power mechanism of the new pipe-laying machine with double throttle valve one-way speed regulation and mechanical rigid connection are simulated by AMESim.Analysis step signal switching push-pull make a study and front end resistance non-linear real-time feedback,the hydraulic system design is reasonable,in the process of continuous push and pull pipeline hydraulic circuit instantly against all kinds of front end resistance surge and lower flow rate adjustment,then realize the continuous pipe laying,and laying rate is relatively stable.To carry out the continuous pipe laying method prototype experiment and the new pipe laying machine simple pipe holding device holding force experiment.The continuous pipe laying method prototype experiment proves that the inner surface of slips can better realize push-pull operation after adding rubber,and the continuous push-pull control program can complete the alternating continuous pipe feeding,which conforms to the field application of continuous pipe laying method.The experimental results show that the new pipe-laying machine can achieve axial push and pull force to radial holding force,which overcomes the technical problem of radial force when traditional pipe-laying machine holds hydraulic cylinder.Innovative lever principle-connecting rod mechanism to achieve small force to do big work,to solve the problem of insufficient holding force of traditional pipe pushing machine.