Page 60 - Air and Gas Drilling Manual

2-10 Air and Gas Drilling Manual
the drill string is designed to allow the stripper rubber to be stripped over the drill
collars to the drill bit.
The procedures for placing the drill string into a well and removing it from the
well must be carefully followed when a well is making natural gas or geothermal
steam or hot water (or any other dangerous gases or fluids). There are other
operations performed by a drilling rig that involve the use of the rotating head and
that must be carefully carried out if a well is making gas or geothermal steam (e.g.,
placing a casing string or a liner string in a well).

Figure 2-9: Rotating internal parts of the rotating head (courtesy of Williams Tool
Company).

Figure 2-10 shows a cut-a-way view of a typical rotating head. This figure
shows the rotating head in the drilling position with the kelly inside the head. The
kelly drive section has a kelly bushing which can be changed to accommodate
various kelly designs. The spindle subassembly rotates with the drill string. The
spindle housing subassembly (which does not rotate) seats into the main body