By-Pass Valve By-Pass Valve is a tool which goes on circulation or well control, when it happens overflowing during drilling, and drilling head water hole is blocked up, does not go on well control. Use：By-pass valve of drill tool is usually assembled on the top of bit and only sub in the drilling course normally. When the water holes of bit in borehole can not circulate regularly, bypath circulation will be carried out by this tool to prevent sticking of tool. This tool is easy and reliable in use. Structure and principle of work ：The structure of the tool is simple. It is made up of body, valve seat, shear pin, steel ball and o-ring seal.Bypass valve of drill tool is usually assembled on the top of bit and only sub in the drilling course normally. When there is possibility sticking drilling tools at the time that mud can not circulate regularly through the water hole of bit in borehole, ought to carry out circulating mud to prevent sticking drill tool. Drop a steel ball in borehole at the time when you want to circulate mud. After the ball comes onto the valve seat of bypass valve, increase mud pressure to ****5MPa until the two shear pins are cut off. Mud pushes valve seat downwards to show the four oblique holes through which bypath circulation can carry out. So you can effectively prevent sticking of drill tool.
