Abstract: A method for increasing an amplitude of reciprocal axial extensions and contractions of a shock tool configured to induce axial oscillations in a drillstring during drilling operations includes (a) selecting the shock tool. The shock tool has a central axis and an axial length. The shock tool includes an outer housing, a mandrel telescopically disposed within the outer housing, and a first annular piston fixably coupled to the mandrel. The shock tool has a first amplitude of reciprocal axial extension and contraction at a pressure differential between a first fluid pressure in the outer housing and a second fluid pressure outside the outer housing. In addition, the method includes (b) fixably coupling a second annular piston to the mandrel of the shock tool and increasing the axial length of the shock tool after (a). The second annular piston is axially spaced from the first annular piston.

Abstract: A method for increasing an amplitude of reciprocal axial extensions and contractions of a shock tool configured to induce axial oscillations in a drillstring during drilling operations includes (a) selecting the shock tool. The shock tool has a central axis and an axial length. The shock tool includes an outer housing, a mandrel telescopically disposed within the outer housing, and a first annular piston fixably coupled to the mandrel. The shock tool has a first amplitude of reciprocal axial extension and contraction at a pressure differential between a first fluid pressure in the outer housing and a second fluid pressure outside the outer housing. In addition, the method includes (b) fixably coupling a second annular piston to the mandrel of the shock tool and increasing the axial length of the shock tool after (a). The second annular piston is axially spaced from the first annular piston.

Abstract: A shock tool for reciprocating a drillstring includes an outer housing. The outer housing has a central axis, a first end, a second end opposite the first end, and a passage extending axially from the first end to the second end. In addition, the shock tool includes a mandrel assembly coaxially disposed in the passage of the outer housing and configured to move axially relative to the outer housing. The mandrel assembly has a first end axially spaced from the outer housing, a second end disposed in the outer housing, and a passage extending axially from the first end of the mandrel assembly to the second end of the mandrel assembly. The mandrel assembly includes a mandrel and a first annular piston fixably coupled to the mandrel. The first annular piston is disposed at the second end of the mandrel assembly and sealingly engages the outer housing.

Abstract: A shock tool for reciprocating a drillstring includes an outer housing. The outer housing has a central axis, a first end, a second end opposite the first end, and a passage extending axially from the first end to the second end. In addition, the shock tool includes a mandrel assembly coaxially disposed in the passage of the outer housing and configured to move axially relative to the outer housing. The mandrel assembly has a first end axially spaced from the outer housing, a second end disposed in the outer housing, and a passage extending axially from the first end of the mandrel assembly to the second end of the mandrel assembly. The mandrel assembly includes a mandrel and a first annular piston fixably coupled to the mandrel. The first annular piston is disposed at the second end of the mandrel assembly and sealingly engages the outer housing.

Abstract: A shock assembly for use with a motion tool deployable into a wellbore by a conveyance. The motion tool includes a mandrel operatively connectable to the conveyance or the motion tool, a housing operatively connectable to the motion tool or the conveyance (the housing having an opening to slidingly receive the mandrel and including a first and a second spring portion), a first spring slidably positionable in the first spring portion and having a first spring stiffness, and a second spring slidably positionable in the second spring portion having a second spring stiffness. The second spring stiffness being less than the first spring stiffness such that the first and second springs selectively engage as the housing slidingly moves about the mandrel in response to forces applied to the system to selectively restrict movement between the mandrel and the housing whereby the motion tool is vibrated.

Abstract: A shock assembly for use with a motion tool deployable into a wellbore by a conveyance. The motion tool includes a mandrel operatively connectable to the conveyance or the motion tool, a housing operatively connectable to the motion tool or the conveyance (the housing having an opening to slidingly receive the mandrel and including a first and a second spring portion), a first spring slidably positionable in the first spring portion and having a first spring stiffness, and a second spring slidably positionable in the second spring portion having a second spring stiffness. The second spring stiffness being less than the first spring stiffness such that the first and second springs selectively engage as the housing slidingly moves about the mandrel in response to forces applied to the system to selectively restrict movement between the mandrel and the housing whereby the motion tool is vibrated.