.~ Chemical reaction with earth formation or drilling fluid constituent
DEFINITION
Classification: 175/64
(under subclass 57) Processes comprising (1) introducing a material into a borehole to react chemically with the in situ earth formation to form the borehole or (2) introducing a material into the borehole during drilling to react chemically with a material present in the drilling fluid.
(1) Note. The term "during drilling" is defined as that period in which the actual drilling or hole making step is in progress and does not include the whole period of time required to form a completed bore in which actual hole making operations may have been temporarily stopped numerous times.
(2) Note. Drilling fluids generally deposit a cake or mud sheath upon the wall of a bore. Such deposits are not considered cementing, plugging or consolidating in the sense used in the definition of Class 166, subclass 285. However, when one step of a cementing process is done during drilling, as by adding one constituent of a resin type cement in the drilling fluid while drilling, and another step is performed after drilling has stopped, as by adding the remaining constituent of the resin cement, such a process is considered to be performed while drilling has been interrupted and is classified in Class 166 subclasses 285+.
SEE OR SEARCH THIS CLASS, SUBCLASS:
12, for processes and apparatus for forming earth bores by the combustion of the earth formation material.
13, for processes and apparatus for forming earth bores by the application of heat with the introduction of a slag forming flux to the bore. SEE OR SEARCH CLASS
166, Wells,
300, for well processes involving chemical inter-reaction of introduced material.
