Study On The Key Technology Of New Type Of Pressure Drilling Device With Drill

In the drilling operation of oil and gas wells, in order to prevent the kick and blowout drilling accident, the reliable well control equipment is necessary. Well control equipment is a set of special equipment to implement oil and gas well pressure control of technology, instrumentation equipment and tools. Well control equipment, as a set of key equipment to detect and control kick, prevent blow out, protect the safe of people and equipments, is playing an increasingly important role in the safety and security of the entire drilling project. In the drilling operation of oil and gas wells, because of the various factors often changes, such as meetiing high pressure oil and gas, the pressure balance of the oil and gas wells may damage, that can cause a well kick or blowout. Even if the BOP is closed to control the oil and gas well’s mouth, but for all kinds of reasons, such as the interior tools like plug valves can’t be opened normally, that would cause the more complicated accident because of no pressure well channel is provided.In the above view of well control equipment in control of overflow when the possibility of failure problem may occur, puts forward the drill hole with pressure device, this device can quickly take a hole in the drill pipe with pressure. This device also supports pressure well choke function, thus builds new drilling fluid circulation channel in the drill pipe, resumes the formation pressure control, makes a blowout accident get timely control.However, the hot tapping technology research for the drill pipe at home and abroad is very little, and the hot tapping technology research for the pipeline is quite mature.In this paper, according to the aforementioned situation when a well kick or blowout, on the basis of detailed investigation and analysis of the hot tapping technology and supporting tools at home and abroad, improve the hot tapping devices existing shortcomings such as the working pressure is not high, the working pressure seal is lax, drive mechanical structure is complex, open hole process is not quite stable, to establish a seal chamber body and drill a hole on the side of drill pipe with pressure for 70 MPa. It can effectively seal the drill pipe after take a pressure hole to prevent high pressure fluid leakage, this new hot tapping device is still supporting kill and put spray function, thus build a new drilling fluid circulation channel in the drill pipe, regain control over the formation pressure.In this paper the specific work as follows:(1) Literature research of the hot tapping technology at home and abroad. Collate and study the information collected, analyze the development of the technology of hot tapping at home and abroad, and study the shortcomings of the existing hot tapping devices.(2) Research of the hot tapping device’s structure and working principle. Depth analysis of the typical structural characteristics and working principle of several hot tapping device. Learn their research ideas and methods. Combining with the actual working condition, determine the structure design principles and methods.of the device of drill pipe with pressure.(3) The overall hot tapping device’s structure design. Design two types of hot tapping device schemes and choose its optimization. Introduce the overall realization of the process of the drill pipe hot tapping and killing.(4) Study of the fluid flow characteristics of the drill pipe model in the process of killing. Based on the two kinds of structure design scheme, establish the fluid domain model of the drill pipe openings after the killing process, analyze the drill pipe orifice in fluid characteristics, study the flow field characteristics in the device after drilling a hole, and further test the optimized design scheme of rationality. On the basis of selection of structure design, mainly research the law of open hole orifice size on the influence of the maximum velocity near the hole.(5) Mechanical properties of the main components. Study the residual strength of the drill pipe after drilling a hole, verify the opening dill pipe remaining the strength to meet the requirements. Take the internal thickening form drill pipe as the research object, draw a curve of the laws of the hole diameter size on the influence of the residual strength of drill pipe. Use finite element analysis methods to check the strength of the key parts of the hot tapping device, ensure the components can work properly and steadily under the high-pressure.(6) Research of the sealing systems of the hot tapping device. Analyze the static sealing of the o-type sealing ring in the seal grooves of the fixed screw shaft.Put forward the dynamic seals design scheme in the cutting tools, and analyze the dynamic seal of J-shaped slip ring seal in the reciprocating arbor shaft with finite element analysis methods, verify the sealing reliability of both respectively.(7) Design the prototype bench experiment test scheme. Through the experiment method to verify the hot tapping device under high-pressure whether meet the requirement, also can verify the feasibility of structure design of the hot tapping device.