Abstract: A downhole well drilling apparatus includes an above-ground mast and an axially elongated generally cylindrical pneumatic hammer drill supported by the mast and mounted in an axially vertical above-ground position. An installation and removal adapter mounted on the lower end of the pneumatic hammer drill couples the hammer drill to a pipe string and maintains a movable part of the hammer drill in an operative condition at all times thereby enabling the hammer drill to operate while rotational torque and upward directed force are simultaneously applied to the operating hammer drill by the apparatus during removal of a casing from a downhole position. Hammer operation is controlled by a manually operable air supply valve.

Abstract: A downhole well drilling apparatus includes an above-ground mast and an axially elongated generally cylindrical pneumatic hammer drill supported by the mast and mounted in an axially vertical above-ground position. An installation and removal adapter mounted on the lower end of the pneumatic hammer drill couples the hammer drill to a pipe string and maintains a movable part of the hammer drill in an operative condition at all times thereby enabling the hammer drill to operate while rotational torque and upward directed force are simultaneously applied to the operating hammer drill by the apparatus during removal of a casing from a downhole position. Hammer operation is controlled by a manually operable air supply valve.

Abstract: A downhole well drilling apparatus includes an above-ground mast and an axially elongated generally cylindrical pneumatic hammer drill supported by the mast and mounted in an axially vertical above-ground position. An installation and removal adapter mounted on the lower end of the pneumatic hammer drill couples the hammer drill to a pipe string and maintains a movable part of the hammer drill in an operative condition at all times thereby enabling the hammer drill to operate while rotational torque and upward directed force are simultaneously applied to the operating hammer drill by the apparatus during removal of a casing from a downhole position. Hammer operation is controlled by a manually operable air supply valve.

Abstract: A slurry diverter for use in well drilling of the type in which a drill shaft is rotated to drill a bore into the ground includes a housing having a top end with an upper surface and a first aperture within the top end of the housing. The housing also has a second aperture which permits entry of slurry from the drilling bore into the housing. The first and second housing apertures are aligned with the bore during use and permit the drill shaft to pass through the housing. The housing also has an exit port which permits slurry to exit the housing so that the slurry can be diverted away from the drilling site. The slurry diverter further comprises at least one flexible wiper positioned above the upper surface of the top end of the housing. The wiper has a central aperture which is coaxially disposed with the first housing aperture. The wiper seals with the drill shaft such that substantially none of the slurry entering the housing can pass through the first housing aperture.