【Summary】Drill pipe is divided into three categories: kelly pipe, drill pipe and weighted drill pipe. The connection sequence is kelly pipe (1 piece)+ drill pipe (n pieces, determined by the well depth)+ weighted drill pipe (n pieces, determined by the drill assembly design).
Drill pipe is divided into three categories: kelly pipe, drill pipe and weighted drill pipe. The connection sequence is kelly pipe (1 piece)+ drill pipe (n pieces, determined by the well depth)+ weighted drill pipe (n pieces, determined by the drill assembly design).
Drill pipe is the basic component of drill string. Its main function is to transfer torque and transport drilling fluid, and by gradually lengthening the drill pipe to deepen the hole. Therefore, drill pipe plays a very important role in oil drilling.
Drill pipe structure Drill pipe is made of seamless steel pipe, the wall thickness is generally 9 ~ 11mm; The pipe body composed of the drill pipe body and the drill pipe joint is welded together with the joint by friction welding.
The kelly pipe is located at the upper end of the drill string and is available in two types: square and six.
When drilling, the kelly is matched with the bushing and the turntable bushing to transmit the ground rotating torque to the drill rod to drive the drill string and bit rotation;
Bear the full weight of the drill string;
③ Channel of drilling fluid circulation.
Kelly pipe consists of upper and lower joints and pipe body parts. The pipe body part is of two kinds of structure (most of the oil drilling is of four square structure); The upper connector is the left female thread (reverse button), connected with the faucet, in the rotation process of the left female thread to prevent reverse; The lower joint is right-handed male thread and is connected with the drill pipe. When working, the upper end of the kelly is always above the turntable surface and the lower part is below the turntable surface.
The weighted drill pipe is similar to the oil drill pipe, which is also a hollow steel column with a length of about 10 meters. However, the single weight is heavier than the oil drill pipe, the wall thickness is 2 to 3 times that of the drill pipe, and the drill pipe is connected between the drill pipe and the drill pipe, the purpose is to prevent the fatigue damage when the drill string cross-section changes, and it can also replace the role of a part of the drill collar, but its suspension is simple, the operation of tripping is convenient, and the tripping time can be saved.
The kelly pipe is located at the upper end of the drill string, and its main role is to transfer the torque and withstand the total amount of the drill string. The end face of the drive part of the kelly pipe is divided into square and hexagon, the more square is used in oil drilling, and the water eye is a regular hexagon, because the wall thickness is about three times that of the drill pipe, and is made of high-strength alloy steel, so it has high tensile strength and torsional strength.MORE
The drill pipe is the hub connecting the surface and the underground. In rotary drilling, the drill string is used to transfer the energy needed to break rock, apply weight on bit to the bottom of the well, and transport drilling fluid in the well. When drilling with downhole power drilling tools, it withstands the reverse torque of downhole power drilling tools and delivers liquid energy to downhole power drilling tools at the same time.MORE