Do You Know Anything About Casing Head?

The casing head is used to fix the wellhead of the drilling well, connect the wellhead casing string, support the gravity of technical casing and oil casing, seal the annular space between the pipe layers and provide transition connection for the installation of BOP, tubing head, and Christmas tree. In addition, it can be applied to some construction work such as mud injection, monitoring, and filling equilibrium liquid through the two side openings of the casing head body.

The wellhead casing head is generally made of 35 or 42 chromium molybdenum high-quality alloy structural steel. There are casing hangers inside the casing head which are used to hang the casing string of corresponding specifications and to seal the space gap between the rings. BOP stack shall be installed on it. After oil well completion, the oil well x-mas tree shall be installed on the casing head.

Casting head is a special short joint made by connecting the top of the casing string with a screw thread or flange plate and located in the outer casing to support and fix the casing string in the well as well as install BOP stack and other wellhead devices when drilling on land or offshore.

The production process of the casing head is generally as follows :

1. Cast the blank: cast the material into the work blank.

2. Rough cutting: carry out the primary machine work for the work blank.

3. Finish turning: process the rough-cut workpiece to the design accuracy with the lathe.

4. Bore the diameter: bore the designed inner diameter with the boring machine.

5. Drill the hole: drill out the outer connection bolt hole with a drill press.

6. Heat treatment: process the workpiece with quenched-tempered heat treatment.

7. Inspection and test: After the machining process of the casing head is completed, the test of geometric dimension, hardness, roughness, internal and external defects inspection, and non-destructive testing shall be carried out.