Difference Between Oil Casing and Oil Drill Pipe

The casing is used to strengthen the well wall, and the inner and outer diameters are much larger than the drill rod; the drill rod is used to connect the drill collar and the drill bit, and the length is sufficient to support the drill bit in the downhole operation. Regardless of function or size, they are all different.

The essence of the casing pipe is:
1. During the drilling process, as the depth of the well increases, the required mud density will increase, and the upper bottom layer may be leaked. The role of the casing is to prevent the upper layer from being leaked when drilling the lower layer.
2. The last oil pipe and tail pipe is the oil passage. The purpose is to stabilize the formation and prevent collapse. If the formation is hard, the well can be completed with open holes.

Open-hole completion can only be applied to a single oil or gas layer with hard and dense rock formations, no water-containing interlayers, and no easy-to-collapse interlayers or some oil and gas layers with the same properties and similar pressures.

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