Research And Development On Multilayer Fracturing Automatic Control Device

At present,because the size of casing is fixed,and the size of bowling and ball seat changes from small to large in a limited space,so the number of fracturing layers of the ball-throwing fracturing technology of single string is extremely limited(generally around 1-6 layers),often can not meet the requirements of multi-layer fracturing,while the operation procedures are strict,the order of shot must be strictly in accordance with the order from small to large.Otherwise,leakage would be occured,which would seriously affect the quality of construction and the effect of construction,and even cause serious fracturing accidents,resulting in serious losses.Considering above-mentioned problem which puzzled the oil field construction units for many years and regared as the "old,big and difficult" problem,our team has developed a real multi-layer(theoretically infinite layer fracturing)fracturing technology,namely” Multilayer Fracturing Automatic Control Device”,based on the prototype of ball-throwing fracturing tool.The multi-layer automatic fracturing control system is designed in the device innovatively.The size of the variable diameter ball seat can be changed through a series of procedure,firstly,the pressure signal can be measured by a pressure sensor mounted on the switch ring seat,then the signal will be transmitted to the single chip computer which can control the inner motor driving the switch ring to rotate,so that the external high-pressure liquid enters the fracturing device inner,and pushes the piston up,and then changes the radial size of the variable diameter ball seat,eventually achieved the goal of changing the diameter of the ball seat.And the goal of multi-layer fracturing with the same size ball is realized ultimately.On the basis of theoretical analysis,indoor field tests were carried out on the device in the later stage,and the results are good,which is of great significance to the follow-up work.