In the context of oilfield drilling, “breakout cathead” and “spinning cathead” refer to different types of catheads used for making and breaking connections on drill pipe. Breakout catheads, with teeth, are used for the more aggressive operation of breaking out joints, while spinning catheads (often called makeup catheads) are used for the gentler process of spinning the pipe to make a connection.
Here’s a more detailed breakdown:
Breakout Cathead (with teeth):
- Purpose:Primarily used for breaking apart connections on drill pipe, often in reverse rotation to loosen the joint.
- Mechanism:The teeth on the cathead engage with the pipe joint to provide the necessary torque and force to separate the pipe.
- Location:Typically located on the opposite side of the driller’s side of the drawworks.
Spinning Cathead (makeup cathead):
- Purpose: Used for spinning the drill pipe to make connections, often in conjunction with a rotary table or kelly spinner.
- Mechanism: These catheads provide the rotational force needed to thread the drill pipe joints together.
- Location: Usually located on the driller’s side of the drawworks.
Key Differences Summarized:
| Feature | Breakout Cathead | Spinning Cathead |
|---|---|---|
| Primary Function | Breaking connections | Making connections |
| Teeth | Present | Absent |
| Rotation | Primarily reverse | Primarily forward |
| Drawworks Side | Opposite driller | Driller’s side |
