Abstract: A sound attenuating apparatus for noise bearing fluid streams wherein elongated perforated wall forming panel sheets include integrally formed indentations extending along a direction transverse the direction of the fluid stream to provide strength and stiffeners for the perforated panel sheets.

Abstract: A sound attenuating apparatus and method for forming the same including stacking selectively sized sheets of sound attenuating materials and fastening the same to form elongated, perforated sound attenuating flow-through passages which are structurally connected by means of mechanical joinders outside the noise bearing fluid stream to be attenuated.

Abstract: A three roller centralizer is expandable from a position with the rollers retracted to a position with the rollers extended to a larger diameter for remaining concentric in a hole being underreamed. A diagonal camming surface is fixed on the body above each such roller. An axially shiftable diagonal camming surface is mounted on a piston below each such roller. Application of hydraulic pressure on the piston squeezes the rollers outwardly toward their extended position. After the rollers are fully extended, the lower camming surface can travel further so that axially extending surfaces above and below each roller prevent collapse of the rollers toward the retracted position. Links pivotably interconnect the carrier for such a roller and the body and lower camming surface respectively for retaining the rollers. Such a link has an elongated opening so that the carrier can move along the diagonal and axially extending surfaces instead of being limited to a circular path.

Abstract: This underreamer has a lower body and a tubular upper body connected above it. A pair of extendible cutter arms are scissored in the lower body for pivoting between retracted and extended positions. A sleeve fixed to the lower body extends upwardly within the upper body with an outside diameter smaller than the inside diameter of the upper body to leave a fluid flow annulus between the sleeve and upper body. A piston in the sleeve is axially movable from an upward position toward a lower position in response to application of fluid pressure through a drill string for pivoting the cutter arms from the retracted position toward the extended position. Passages through the lower body convey drilling fluid through the lower body from the annulus between the upper body and the sleeve. Such fluid is discharged outside the lower body adjacent to cutters on the cutter arms, into a pocket in the lower body occupied by the cutters in their retracted position, and through the lower end of the lower body.

Abstract: A milling tool for removing a packer from a well includes a releasable catcher for supporting remains of a milled packer (51). The catcher has a sleeve (26) with deflectable fingers (29) which normally support the remains of the packer. If the packer should become stuck, the fingers (29) press on a release ring (39) which has a ramp (43) that engages a complementary ramp (42) on a shoulder (41) on the mandrel (14) of the mill. The ramps cam the ring outwardly until the ring breaks in tension at a deliberately weakened location (52). This releases the sleeve (26) to slide downwardly and permit the fingers (29) to deflect inwardly into a recess (23), thereby clearing the bore of the stuck packer.

Abstract: A hole drilling tool, useful in mining operations for enlarging the lower portion of a hole for explosives, is described. This underreamer has arms movable between a retracted position and an extended position for underreaming in response to weight of the drill string above the tool. The two cutter arms are urged outwardly into their extended position by a cam connected to the upper end of the drill string. In effect the cutter arms are connected to the lower end of the drill string which can telescope relative to the upper end. An air flow passage extends from the tool body through the cutter arms for cooling the cutter bearings.