Hydraulic straight hole drill collar

Patent · Tue Jan 15 04:00:00 EST 1985

OSTI ID:5704994

Townson, J D

An improved drill collar for forming relatively straight holes in crooked hole type formations. One or more hydraulic drill collars are connected in series relationship within a drill string above a rotary bit at the point of tangency. Each drill collar includes at least one outwardly opening, longitudinally extending slot formed on the exterior thereof. The slot includes a back wall connected to confronting sidewalls and opposed end walls. One lower end of a slot commences in spaced relationship to the lower pin end of the collar. As the drill string is rotated, drilling fluid forms a cushion between the slot and the nearest sidewall of the borehole, thereby kicking or forcing the drill collar away from the borehole sidewall, which in turn forces the drill bit to penetrate in a downwardly direction back towards a vertical position. The borehole meanders a very small amount, as for example 3-4 degrees, rather than uncontrollably leaving the vertical and forming an excessively crooked hole. Various configurations and arrangements of slots are disclosed in the collar.

• Assignee: EDB-85-111165
• Patent Number(s): US 4493380
• OSTI ID: 5704994
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
020300* -- Petroleum-- Drilling & Production
03 NATURAL GAS
030300 -- Natural Gas-- Drilling
Production
& Processing
BOREHOLES
CAVITIES
DRILL BITS
DRILL PIPES
DRILLING EQUIPMENT
DRILLING FLUIDS
DRILLING RIGS
EQUIPMENT
FASTENERS
FLUIDS
HYDRAULIC EQUIPMENT
INCIDENCE ANGLE
MECHANICAL STRUCTURES
PIPES
SUPPORTS
WALLS