The pipe string is lowered to the predetermined position; during fracturing, the soluble fracturing ball is thrown from the wellhead, and the soluble fracturing ball is sealed on the soluble ball seat. In a specific structure of the present utility model The medium soluble fracturing ball is sealed to the second section of the soluble ball seat and pressed. When the pressure reaches the set opening value of the sliding sleeve, the scissors are cut and the valve is opened to fracturing the oil pipe. After the fracturing is completed, the flowback Fracturing fluid, please produce. As fracturing proceeds, the soluble ball seats and soluble fracturing balls slowly dissolve in the fracturing fluid. When the surface film is completely dissolved, the matrix material begins to dissolve rapidly until the ball seats and fracturing balls completely disappear. Thereby achieving a large diameter of the sliding sleeve.
[0018] This kind of soluble ball seat/soluble fracturing ball can withstand high pressure during fracturing, and can automatically dissolve downhole after fracturing, and can be used for secondary transformation and other subsequent operations without drilling and grinding. , low risk and cost saving.
Sovereign Item
1. A soluble ball seat for a pitching slide, which is characterized in that: it is made of an electrolytic metal material ball seat base (I) and is covered with The oxide film (2) on the surface of the ball seat base (I) is composed of; the electrolytic metal material is Mg-Zn-Cu alloy; the oxide film (2) is a magnesium oxide layer or a zinc oxide layer.
2. The soluble ball seat for a pitching slide as claimed in claim 1, characterized in that: the soluble ball seat includes three sections connected in sequence as one, the first section being the upper The second section is a cylindrical cylinder, and the third section is a conical cylinder with a small top and a large bottom.
3. A soluble fracturing ball used in conjunction with the soluble ball seat according to claim 1, characterized in that: the ball (3) is made of electrolytic metal material and is coated in The surface is composed of an oxide film I (4); the electrolytic metal material is Mg-Zn-Cu alloy; the oxide film I (4) is a magnesium oxide layer or a zinc oxide layer.
4. A soluble fracturing ball used in conjunction with the soluble ball seat according to claim 2, characterized in that: the ball (3) is made of electrolytic metal material and is coated in The oxide film 1 (4) on its surface is composed of; the electrolytic metal material is Mg-Zn-Cu alloy; the oxide film 1 (4) is a magnesium oxide layer or a zinc oxide layer; the diameter of the soluble fracturing ball Greater than the diameter of the second section of the soluble ball seat.
Patent abstract The utility model discloses a soluble ball seat and a soluble fracturing ball for a pitching sleeve. The soluble ball seat is made of an electrolytic metal material ball seat base and a ball covered with The soluble fracturing ball is composed of an oxide film on the surface of the base body; the soluble fracturing ball is composed of a ball made of electrolytic metal material and an oxide film I covering its surface; the electrolytic metal material is Mg-Zn-Cu alloy, oxide film and oxide film I Both are magnesium oxide layer or zinc oxide layer. The soluble ball seat for pitching sliding sleeves is used in conjunction with fracturing balls and can be dissolved in a solution containing Cl-. When the ball seat and fracturing balls are dissolved, the sliding sleeve can be realized without drilling and grinding the ball seat. Large diameter.
IPC classification E21B34-14, E21B43-26
Publication number CN204492756
Application number CN201520100388
Inventors Cheng Zhiyuan, Li Mei, Liu Zhibin, Luo Jinyu, Zhang Peng, Han Yongliang, Zhan Hongyun, Cui Zhenmao, Zhou Houjun
Applicant China National Petroleum Corporation Bohai Drilling Engineering Co., Ltd.
Opening date: July 22, 2015
Application date: February 12, 2015