Coil tubing hydraulic jar device

#1. Field of the Invention

#The invention relates generally to jar devices for use during downhole fishing operations and the like and more particularly, but not by way of limitation, it relates to a dual acting hydraulic jar device that can be actuated via coiled tubing by both lift-up and set-down of supporting string weight.

#2. Description of the Prior Art

#FIGS. 1A, 1B, 1C and 1D are sequential vertical sections of the jar device of the invention shown at the up jar positioning;

#FIGS. 2A, 2B, 2C and 2D are sequential views in vertical section of the jar device in the lowermost or down jar position;

#FIGS. 3A, 3B, 3C and 3D are sequential views in vertical section of the jar device nearing completion of an up jar stroke;

#Referring to FIGS. 1A to 1D, a jar device 10 consists essentially of an outer cylindrical member 12 having an inner reciprocal member 14 disposed therein for sliding movement. The outer cylindrical member 12 consists of an upper kelly cylinder 16, an intermediate hydraulic cylinder 18 and a lower sub 20. The inner reciprocal member 14 consists of an upper cylindrical piece formed as a mandrel 22 having an annular shoulder 24 with downward-facing annular striker surface 25 formed on the upper end of mandrel 22 and having threads 26 formed around the lower end.

#A flat 27, formed as a chordal plane through sector radii of about 45.degree. separation, is formed on said cylindrical mid-portion 23 of mandrel 22. The flat 27 extends from a point 31 adjacent mandrel annular shoulder 24 continuously down to a point 33 adjacent the mandrel threads 26. See also, the section of FIG. 7 illustrating the concentric relationships to hammer sub 66 which includes the aligned set screws 65 and 67 in respective threaded holes 69 and 71. The set screws 65 and 67 are set inward against the flat 27 to maintain rigid alignment of the mandrel 22 and outer hammer sub 66 as secured to the kelly cylinder 16.

#An anvil sub 28 is formed with cylindrical outer surface 29 and an upper annular bore 30 having inner sidewall 32 with threads 34 formed therearound. The annular end surface 36 forms as an up jar striking surface, as will be further described below. The lower end of anvil sub 28 is formed with an axial bore 38 having internal threads 40. Threadedly secured upwardly within bore 38 is a threaded end 42 of an actuating plunger 44. The actuating plunger 44 extends down through the hydraulic cylinder 18 (FIG. 1C) into the lower sub 20 and includes an upper seal face 46 which defines a lesser diameter slide way 48 adjacent to threads 50 having a block nut 52 threadedly secured thereon. A lower plunger 54 extends below threads 50. An axial port 55 extends down through mandrel 22 and plunger 44, 54. A meter ring 56 forming a sliding valve is suitably retained on slideway 48. The diameter of meter ring 56 is a selected small amount less than the inside diameter of a restrictor 58 disposed generally in the center of hydraulic cylinder 18. The restrictor 58 is about two inches in length as it functions with the mandrel plunger 44, seal face 46 and meter ring 56 to actuate the jar device, as will be further described below.