Drill pipe is a steel pipe with indulge grain on the tail, which is used to connect the surface equipment of the drilling rig to the drilling and grinding equipment or bottom hole device located at the bottom of the drilling rig. The purpose of the drill pipe is to transport drilling mud to the bit and to lift, lower or rotate the bottom hole device with the bit. The drill pipe must be able to withstand tremendous internal and external pressure, distortion, bending and vibration. In the process of oil and gas extraction and refining, drill pipe can be used many times.
Geological drill pipe is a geological alloy steel pipe by friction welding process design and production of geological drilling tools, geological drill pipe body using geological special alloy steel pipe (R780, DZ50), geological drill pipe joint using high-quality alloy structural steel (42CrMo) by real air conditioning quality treatment, greatly improve the fatigue strength and shear strength. The geological drill pipe is produced and processed by excellent friction welding technology. The drill pipe has the characteristics of high bending strength and solid welding, which can ensure the straightness requirement during deep hole drilling, and has high fatigue strength and long service life.
As long as the drill pipe passes through the bend of the hole, even if the tension is eliminated, the accumulated fatigue damage still exists, so if the drill pipe passes through the bend of the hole several times, it is possible to fatigue damage the drill pipe. It is also important to note that a drill pipe in a given well may have been damaged even if there was no accident. Therefore. When it is used in the same well or another well, although it is attached to the top of the drill string, even if the bending stress acting on the drill pipe is within the rated value, it may become unbearable and cause accidents.
In the construction process, the use of trenchless drill pipe should avoid diameter drill pipe with small diameter drill pipe, that is, large and small drill pipe mixed use, to prevent the small drill pipe due to insufficient strength to be broken or deformed phenomenon; Before installing the oil drill pipe, it is necessary to clean the female button and male button in time, and put on the thread button oil to prevent premature wear or damage to the button.