This class relates to processes or means not otherwise classifiedcomprising (1) shafts or deep borings in the earth, commonly knownas wells, for the extraction of fluids from the earth, (2) shaftsor deep borings in the earth for inserting a fluid into the intersticesof a porous earth formation, usually to enable withdrawal of fluid froma producing output well, (3) apparatus peculiarly adapted for treatinga well or for use in or with a well, or (4) processes of using,making, or treating a well.
This class takes combinations of elements or process stepsrelating to wells and going beyond the scope of subcombinations,such as measuring or testing means or pumps, classifiable, per se,in other classes. The class also takes subcombinations, such aspackers or expanding anchors, peculiar to wells. However, the classdoes not take various intermediate combinations, such as devicesperforming only a measuring or testing function or a pumping function,which may include subcombinations, such as packers or expandinganchors, as minor perfecting features.
Treating a well includes various miscellaneous processes orapparatus relating to wells; typically, gravel layer forming, cementing,washing or acidizing.