There are two main types of heel drilling used in the market: eccentric heel and concentric heel.
Relatively speaking, the proportion of eccentricity and tube use is relatively large, accounting for about 95% of the market use, which is due to its advantages.
Decided. There are two main advantages to eccentricity compared to concentric heels:
a, the same diameter of the hole is required, the concentric tube is often larger than the eccentric tube needs one level of casing, which undoubtedly increases the material cost, and because the level of the concentric casing is large, which leads to slow progress and The air compressor consumes more fuel.
b. Compared with the concentric tube and the concentric tube, since the drilling of the concentric tube is the same diameter, especially when encountering rock or boulders, drilling will be very difficult, even if the drilling is successful, due to the diameter reduction of the hole. It is also very troublesome to pull up the casing, and it often causes accidents in the hole such as casing breakage.