(under the class definition) Apparatus including above ground means by which the drilling fluid is (1) formed or acted upon prior to or during insertion into the borehole to bring about a change in a physical or chemical property or (2) acted upon after the fluid leaves the borehole to remove, separate or subtract substances, including cuttings, from said fluid.
(1) Note. Means for causing entrainment of cuttings in the drilling fluid are not considered to be drilling fluid treating for the purpose of this subclass. However, separating the cuttings from said fluid is classifiable herein.
SEE OR SEARCH THIS CLASS, SUBCLASS:
17, for heating or cooling the drilling fluid.
65+, for processes of drilling with fluid, particularly subclass 66 for treating used or spent fluid.
205, for pressurized gas contact with drilling fluid.
SEE OR SEARCH CLASS 95, Gas Separation: Processes, for processes of gas separation, particularly
241+, for degasification of liquid.
96, Gas Separation: Apparatus, for apparatus for gas separation, particularly
155+, for degasifying means for liquid.
209, Classifying, Separating, and Assorting Solids, appropriate subclasses.
210, Liquid Purification or Separation, appropriate subclasses.
507, Earth Boring, Well Treating, and Oil Field Chemistry,
