Apparatus for feeding the rods or cables; Apparatus for increasing or decreasing the pressure on the drilling tool; Apparatus for counterbalancing the weight of the rods

Introduced: September 1968

Last revised: January 2006

Full Title

Handling rods, casings, tubes or the like outside the borehole, e.g. in the derrick; Apparatus for feeding the rods or cables > Apparatus for feeding the rods or cables; Apparatus for increasing or decreasing the pressure on the drilling tool; Apparatus for counterbalancing the weight of the rods

Classification Context

Section:: FIXED CONSTRUCTIONS
Class:: EARTH OR ROCK DRILLING; MINING
Subclass:: EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS

Additional Content

Handling reeled pipe or rod units, e.g. flexible drilling pipes Automatic control of the tool feed

7 direct subcodes

Child Classifications

Navigate with arrow keys, Enter to open

E21B 19/081 Screw-and-nut feed mechanisms
E21B 19/083 Cam, rack or like feed mechanisms
E21B 19/084 with flexible drawing means, e.g. cables
E21B 19/086 with a fluid-actuated cylinder
E21B 19/087 by means of a swinging arm
E21B 19/089 with a spring or an additional weight
E21B 19/09 specially adapted for drilling underwater formations from a floating support using heave compensators supporting the drill string

Top Applicants

Top 10 applicants by patent filingsfor class E21, 2013–2023, worldwide · Source: EPO PATSTAT

HALLIBURTON ENERGY SERVICES GROUP US 26,607
PETROCHINA COMPANY 14,382
SINOPEC (CHINA PETROCHEMICAL CORPORATION) 10,137
CNPC (CHINA NATIONAL PETROLEUM CORPORATION) 6,517
BAKER HUGHES US 6,269
SCHLUMBERGER TECHNOLOGY US 5,929
SAUDI ARABIAN OIL COMPANY SA 5,880
SOUTHWEST PETROLEUM UNIVERSITY 4,477
CHINA UNIVERSITY OF MINING AND TECHNOLOGY 4,357
SCHLUMBERGER TECHNOLOGY NL 4,219