A pneumatic hammer is provided with an adjusting piston (37) dependent on the supply pressure, which adjusts the stroke length of the working piston (16). Thereby, the same pneumatic hammer may be operated both at low and high supply pressures. With high supply pressures, either the early ending of the acceleration phase or the early start of the compression phase or the shortening of the working cylinder shortens the stroke length. Thereby, the pneumatic hammer performs impacts with a substantially constant single-impact energy, regardless of the supply pressure. High supply pressures increase the impact frequency. This results in a considerably improved efficiency at a high drill capacity, a reduced wear and a reduced risk of ruptures of the components of the hammer.
A delivery tool is provided for driving fastening devices, for example, U-shaped fastening devices which mount tubing to a surface. The delivery tool has a pivoting structure, including a driving member and a base member. The delivery tool includes a movable ram which is axially guided within the base member to maintain an orientation perpendicular to the surface to drive the fastening devices in a straight manner. A pneumatic impact mechanism is housed within the driving member to assist the ram. The impact mechanism has a concave force delivery member shaped to contact the ram at a generally radial orientation relative thereto, thereby optimally delivering the impact forces to the ram regardless of the angular position of the driving member relative to the base member.
6752222 - Downhole percussion drills - Owned by National Institute of Advanced Industrial Science and Technology (Tokyo,JP) Furukawa Co., Ltd. (Tokyo,JP) K. Maikai Co., Ltd. (Tokyo,JP)
Provided is a downhole percussion drill, which is installed at an end portion of a drillstring and performs drilling by giving impact blows to a drill bit at the bottomhole, which includes a hydraulic hammering mechanism 7 which uses oil having high lubricating ability as a driving medium, a hydraulic pump 8 which pressurizes the oil, and a downhole motor 9 which drives the hydraulic pump 8.
A pneumatic downhole impact drill has a porting system for automatically supplying pneumatic pressure fluid from a fluid delivery tube received within an axial bore in the impact piston to the opposite ends of the piston operating cylinder as the piston reciprocates. A flange on the delivery tube is slidably mounted in a cavity in a mounting hub assembly. Passageways provide fluid communication between the pressure fluid inlet plenum and the operating chamber side of the cavity and between the back chamber and the inlet plenum side of the cavity. Fluid pressure forces acting on the opposite faces of the flange and on the top end surface of the delivery tube reciprocate the delivery tube between upstroke and downstroke positions. Positioning the delivery tube in the upstroke position increases the axial distance that the piston must travel before the pressure fluid supply is connected to the back end of the operating chamber on the piston upstroke. Positioning the delivery tube in the downstroke position increases the axial distance the piston must travel before the pressure fluid supply is disconnected from the back end of the operating chamber on the piston downstroke.
The present invention discloses, in certain aspects, systems and methods for producing cyclical impacts and, in certain aspects for moving a drilling apparatus for drilling a borehole in a formation, the system in certain embodiments including a housing with a longitudinal axis and a movable member movably disposed therein and movable within the housing transversely to the longitudinal axis of the housing and positioned within the housing with a first space on a first side thereof and a second space on a second side thereof, the movable member substantially fluidly isolating the two spaces and movable to compress gas in one of the first space and the second space while decompressing gas in the other space so that a charge of compressed gas exits from the housing to move an impact member; e.g. for impacting a pile to be driven into the earth or for impacting a drill apparatus for drilling a wellbore, the movable member movable continuously to provide a series of impacts.
A method for installing a heat exchange pipe loop in a borehole, the method in at least certain aspects, including drilling a borehole with a sonic drill system having a head and casing connected thereto, a drill shoe on a lower end of the casing movable by the sonic drill head to drill the borehole, pumping fluid (e.g., water and drilling fluid) into the casing, out through a lower end of the casing, and up to earth surface in an annular space in the borehole so that drilled material flows to the earth surface, lowering a heat exchange pipe loop down into the casing, introducing grout into the casing around the heat exchange pipe loop, and extracting the casing from the borehole.