Thick-walled pipe, called Heavy Weight Drill Pipe (HWDP), was
developed to provide a gradual transition from the heavy drill collar to the relatively
lightweight drill pipe. This intermediate-weight pipe has a wall thickness of
approximately 1”, and helps prevent stress
concentration at the top of the drill collar. It also allows you to drill at
higher rpms, reducing torque and differential pressure sticking.
HWDP is intended primarily for directional drilling. Because it bends easily, it
simplifies directional control and minimizes connection fatigue problems common
to high-angle or horizontal drilling. The reduced number of pipe failures and increased
drill-stem service also make HWDP appropriate for some straight-hole
applications.
Various combinations of HWDP, drill collars, and standard drill string can be created
to meet the challenge of severe drilling conditions.
|
|
|
