In the infancy of the petroleum
industry, cable-tool rigs were used to drill for oil
and gas. The first well in North America drilled at
Petrolia, Ontario in 1858 used a cable tool rig.
They were used to “punch” into the ground. A
twenty-five metre wooden derrick was constructed,
with legs braced with horizontal and diagonal
struts. On the derrick floor there were three cable
reels wound with steel cable. One cable was the
drilling line, another cable functioned as the bailer, and the third
cable was used for
lowering and pulling the casting.
There also were three large wheels operated by a
steam engine. Many of the men who worked on these
rigs moved away after the oil industry slumped in the
early 1900s. They took their knowledge and
technology with them to Europe where they found
work.
The invention of the
rotary-drilling rig made cable-tool rigs obsolete,
for all intents and purposes. The rigs, named for
the rotary table through which drill pipe is
inserted and rotated, could make deeper holes
because they used a bit that drilled rather than
pulverized the rock formation. Between 1915 and
1928, rotary rigs slowly replaced existing
cable-tool rigs. The appeal was that rotary rigs
eliminated the laborious, time-consuming bailing
process used by cable-tool rigs to remove rock
cuttings from the hole. Instead, drilling fluid was
circulated down the drill pipe, through the bit, and
up to the surface so rock cuttings created by the
bit were lifted by the fluid and carried to the top.
Cable tools do not effectively control subsurface
pressures, and blowouts were common in cable tool
operations. By the 1930s, the use of steam-powered
engines gave way to the internal-combustion engine
as the most important prime mover. Today’s modern
rotary-drilling rigs are powered by diesel and
diesel-electric engines.
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