摘要:
The hole drilling process is for drilling a hole on a supported tube sheet by using a first drilling tool that can drill a hole with a diameter smaller than that of a mounting hole that is to become a target hole, and a second drilling tool that can drill a hole with a diameter equal to the diameter of the target hole, the process including: a temporary hole drilling step in which a temporary hole with a predetermined depth set beforehand is drilled by moving the first drilling tool to a drilled position set beforehand; a hole measuring step in which a distance (S) between an existing mounting hole and the temporary hole; a drilled position correcting step in which the drilled position is corrected based upon the distance (S) between the mounting hole and the temporary hole.
摘要:
A rock drill bit having a shank fitted with a clamping end and a drilling tip located from the clamping end. The drilling tip has at least three blades and a central zone centered on a drill bit axis. The blades each include on a top side thereof a lip constituted by a leading chipping face and a trailing flank. The lips substantially converge onto each other within a the central zone of the drilling tip, wherein in the central zone, a long lip of the lips runs through the drill bit axis and has a commensurate overshoot segment extending beyond the drill bit axis.
摘要:
A drill bit comprises a plurality of cutting blades arranged circumferentially, the cutting blades having a cutting edge formed by a connecting ridge line between a cutting face and a flank; and a tip formed by coupling radially inner ends of the cutting edges to each other at a center portion of a bit tip end, wherein at least one of the cutting blades has a first flank and a second flank, wherein the first flank has a blade tip side flank close to the cutting edge and a base end side flank formed on the base end side of the blade tip side flank, and wherein a tilt angle α1 of the blade tip side flank 3a is smaller than a tilt angle α2 of the base end side flank 3b which is tilted toward the axial direction.
摘要:
A drill achieves a long tool life while improving a property for discharging chips. The drill includes: a columnar body which is rotated about an axis; a plurality of cutting edges each being formed at a tip end portion of the body; and a plurality of thinning edges each being formed in conjunction with the cutting edge nearer the axis by providing thinnings at the tip end portion of the body. At least one of the plurality of thinning edges is provided with a concave portion that is formed by cutting the thinning edge to be recessed in a semicircular shape toward the rear side in the rotational direction, and a center of the semicircular-shaped concave portion is provided on a line extended from the tip end portion of the thinning edge when viewed from a tip end direction of the body.
摘要:
An edge-carrying drill body intended for deep hole drilling, is rotatable around a central geometric axis and comprises a through-channel arranged for internal chip evacuation. The channel mouths in front and rear ends of the drill body. A front channel mouth is bridged-over by a bridge on which a plurality of cutting edges are formed, which edges are made integrally with the rest of the bridge. The front mouth includes inlets disposed in front of respective cutting edges with reference to the direction of rotation of the body.
摘要:
A deep hole drill is rotatable around a geometric axis and includes a body defining a through-channel arranged for internal chip evacuation. The channel opens in front and rear ends of the body. One or more cutting edges are made integrally with the rest of the body, more precisely from a hard material, such as cemented carbide or CERMET. A front bridge of the body extends across the front channel and possesses the integral cutting edge(s).
摘要:
In order to achieve especially low wear of the drilling tool during drilling and permit drilling with a high feed rate, the invention provides a drilling tool (1) having a shank (3) with a first end (5) and a second end (7), at least one of the ends having a drill head (8, 81, 82) with flutes (10), the drill head having at least three lips (9) and a centering cone (11), and the main cutting edges (91) of the at least three lips of the drill head (8, 81, 82) being relief-ground at least in sections, and the centering cone (11) projecting from an area which is described by the cutting edges (91) by rotation of the drilling tool about its shank axis (2).
摘要:
A high speed drill bit is formed of a longitudinal body designed to rotate about a longitudinal axis. Each flute has a leading edge with a positive rake angle and a trailing edge with a neutral or negative rake angle. The bit cutting face is formed by surfaces and cutting edges that are asymmetrical with respect to each other.
摘要:
A drill for the insertion of a dental implant is disclosed. The drill includes a rotational drive portion in the form of a metal rod with a first end and a second end. The first end is connected to a drilling apparatus. The second end of the rotational drive portion is connected to an active cutting portion made of plastic overmolded on a second end of the metal rod. The drill further includes a metal insert portion coupled to the active cutting portion to serve as a sharp edge for the active cutting portion.
摘要:
An improved self centering spade drill having at least three cutting blades extending radially outward from the center of the drill, the front edge of the blade constituting the cutting portion of the drill, the rear edge of the blade constituting the port end of the drill which are adapted to be received and supported by a drill holder.