Abstract: A joint exhibits high tensile strength. The joint includes a solid rod having a slit or opening into which a wedge is inserted. The rod and wedge are inserted into a fitting. The internal surface of the fitting has a contour which continuously and nonlinearly varies with distance along the fitting. The wedge has a dimension having a similar contour. The shape of the contour can be described by a polynomial of order two or higher. The joint can be used to construct a sucker rod for an oil well, or it can be used in other applications. The joint can support high tensile loads, over long distances, while occupying a very narrow tubing bore.

Abstract: A joint exhibits high tensile strength. The joint includes a solid rod having a slit or opening into which a wedge is inserted. The rod and wedge are inserted into a fitting. The internal surface of the fitting has a contour which continuously and nonlinearly varies with distance along the fitting. The wedge has a dimension having a similar contour. The shape of the contour can be described by a polynomial of order two or higher. The joint can be used to construct a sucker rod for an oil well, or it can be used in other applications. The joint can support high tensile loads, over long distances, while occupying a very narrow tubing bore.

Abstract: A subsurface formation having original in-situ stresses that favor the propagation of a horizontal fracture is penetrated by a borehole. A first fracturing fluid containing a propping material is pumped through the borehole and into the formation at a first depth to propagate a horizontal fracture which alters the in-situ stress field. The pumping of the first fracturing fluid is stopped and a second fracturing fluid is pumped through the borehole and into the formation at a second depth to form a vertical fracture within the field of altered in-situ stress.