Abstract: A release mechanism for a jarring tool is formed by a plurality of segmented release lugs. Each lug includes a plurality of axial spaced projections on an inner surface and a plurality of grooves on an outer surface. The projections have either different widths or are separated by varying distances and releaseably engage corresponding grooves in a mandrel located within a housing of the tool. The release lugs are positioned between a trigger sleeve and the mandrel. The release lugs may be supported by an annular ring member.

Abstract: The invention relates to a cable-operated hammering tool (20) for downhole operations, comprising an extended cylinder (3) with an axially through-going internal opening in the cylinder (3), a hammering part (10) is arranged in a lower section of the cylinder (3) and is fitted with a detachable coupling for the connection with downhole equipment, a release strut (1) is arranged in the upper section of the cylinder (3) that is connected to a cable which is connected to a surface installation, the hammering part is detachably fastened to the cylinder (3) with the help of, at least, one locking body (4). The release strut (1) is functionally connected to a force spring (2) for prestressing of this by moving in a first direction, and also functionally coupled to the, at least, one locking body (4) to be released from this by moving in an opposite direction.

Abstract: Apparatus and method for adjusting spring preloading in a downhole tool. In an apparatus, a mechanism includes a nut and a piston. The nut is configured to axially compress a spring in the downhole tool. The piston is coupled to the nut. Extension of the piston causes the nut to rotate and compress the spring. The nut is configured to maintain compression of the spring after the piston retracts.

Abstract: An impact jar including a biasable member, an impactor and an impactee slidably coupled to the impactor. The impactor includes a first down-hole tool connector. The impactee includes a second down-hole tool connector distal from the first down-hole tool connector and a plurality of flexible coupling fingers. The biasable member is detachably engaged by the plurality of flexible coupling fingers in a pre-impact position and is configured to disengage the plurality of flexible coupling fingers in response to a tensile force applied across the first and second down-hole tool connectors reaching a predetermined quantity. The impactor and the impactee are configured to impact in response to the disengagement of the biasable member and the plurality of flexible coupling fingers. In one embodiment, the impact jar may be employed in either of e-line and slickline applications.

Abstract: An impact jar including a biasable member, an impactor and an impactee slidably coupled to the impactor. The impactor includes a first down-hole tool connector. The impactee includes a second down-hole tool connector distal from the first down-hole tool connector and a plurality of flexible coupling fingers. The biasable member is detachably engaged by the plurality of flexible coupling fingers in a pre-impact position and is configured to disengage the plurality of flexible coupling fingers in response to a tensile force applied across the first and second down-hole tool connectors reaching a predetermined quantity. The impactor and the impactee are configured to impact in response to the disengagement of the biasable member and the plurality of flexible coupling fingers. In one embodiment, the impact jar may be employed in either of e-line and slickline applications.

Abstract: A jar provided with an adjustable triggering load has a housing defining an anvil surface and a mandrel, movable relative to the housing under an applied load, defining a hammer surface to impact the anvil surface. A trigger mechanism for releasing the mandrel to cause the hammer surface to impact the anvil surface includes a trigger sleeve axially positioned within the housing and a collet that engages the mandrel during application of a load to the mandrel. The collet releases the mandrel to cause the hammer surface to impact the anvil surface upon being moved into registration with the trigger sleeve against the resistance of the spring disposed within the housing.

Abstract: A jar tool for inclusion into a well fishing operating string which provides resilient tensional stretch to operate the tool. The tool is adapted to compress an upper release spring to store energy corresponding to tensional force in the operating string forces. A release latching lug array connects the spring to a central mandrel having an impact hammer. The tool housing forms an impact anvil. The spring is compressed to a designated compressional force by the distance that the latch lug array is moved before suddenly releasing the spring from the mandrel. The tension in the operating string then pulls the mandrel hammer into jarring impact with the housing anvil. The provision is made for designating this pre-release movement of the latching lug array and also provides remotely actuated apparatus for adjusting the distance of the pre-release movement and thereby the compressional force imparted into the spring.