A cutting insert has: an upper surface; a lower surface; a side surface, having a first surface and a second surface disposed opposite each other between the upper surface and the lower surface; and a first cutting edge. The lower surface has a plurality of slots extending from a side of the first surface to a side of the second surface. In addition, when viewed from a side of the lower surface, if the angle between a ridge line on which the upper surface and the first surface intersect and an imaginary extension line of the plurality of slots is defined as θ1, and the angle between a ridge line on which the lower surface and the first surface intersect and the imaginary extension line is defined as θ2, then θ2>θ1.

A tool (T) is provided with: a shaft-like tool body (11) having a first end portion (11a) extending along a central axis line (Ot) and attached to a main shaft, and a second end portion (11b) on an opposite side to the first end portion (11a); and a fore end portion (12) connected to the second end portion (11b) of the shaft-like tool body (11). The fore-end portion (12) includes a central portion (13) including a fore-end face (17) of the tool (T), and a plurality of blade portions (14) protruding radially outward from the central portion (13). A cutting blade of each blade portion (14) includes a main cutting blade (15) adjacent to the fore-end face (17). The main cutting blade (15) includes an outline that forms an angle of 30-150 degrees with respect to the central axis line (Ot) in a cross-sectional view including the central axis line (Ot).

In an end mill, eight peripheral cutting edges having a helical shape and a larger outer diameter than that of a shaft portion are in a cutting portion in a circumferential direction. For one peripheral cutting edge of the eight peripheral cutting edges, when a cut length of the peripheral cutting edge along an axial direction is L, a twist angle of the peripheral cutting edge is θ, and a circumferential distance at a lower end of the peripheral cutting edge between the peripheral cutting edge and another peripheral cutting edge adjacent to a tool rotation direction rear side of the peripheral cutting edge is a, n expressed by the following equation is approximately 1 for all of the eight peripheral cutting edges in at least a half region of the cut length from the lower end of the peripheral cutting edge.
n=(L×tan θ)/(2×a)

A method for milling a workpiece by way of at least one substantially polygonal cutting insert, which is arranged in a tool holder. A spindle axis of the tool holder encloses an angle of more than 0° with a plane normal to a machined workpiece surface. An effective lead angle between a main cutting edge of the cutting insert and the machined workpiece surface lies between 0° and 20°.

A surgical bur including flutes and lands. Each of the flutes includes a cutting edge, rake surfaces and a clearance surface. The rake surfaces of one of the flutes are decoupled from each other. Each of the lands is disposed between a pair of the flutes.

A milling machine fly-cutter with adjustable cutting-tool geometric angle and milling machine includes a fly-cutter plate body, a plurality of combination grooves are evenly set in the circumferential direction of the fly-cutter plate body, and adjusting assemblies are mounted in the combination grooves. Wherein, the adjusting assemblies include an adjusting block for rake angle and relief angle, an adjusting block for tool cutting edge angle and minor cutting edge angle, an adjusting block for tool cutting edge inclination angle. A first side of the adjusting block is attached with a cutter handle, and a second side is connected with the adjusting block for rake angle and relief angle by the adjusting block for tool cutting edge angle and minor cutting edge angle. The milling machine fly-cutter realizes adjustment of the geometric angles of cutting tool, and is able to adapt to cutter handles of a variety of different specifications.

A surgical bur includes a body and a drill point. The body includes flutes and lands. Each of the flutes includes a cutting edge, a rake face, and a clearance surface. Each of the lands is convex-shaped and disposed between a pair of the flutes. The drill point includes axial relief surfaces. Each of the axial relief surfaces has a planar area, is distinct from the lands and borders (i) a distal portion of one of the cutting edges, (ii) one of the lands, and (iii) one of the clearance surfaces.

The present disclosure includes a protective tube for insertion into a pipe or vessel containing a medium, a measuring apparatus having such protective tube and to a method for producing the protective tube. The protective tube comprises a tubular member having a bore extending between an upper and lower end of the tubular member, and at least one helical fin formed on at least a section of an outer surface of the tubular member, winding around the outer surface of the tubular member and defining a flow channel along at least a part of the tubular member. An outer surface of the tubular member comprises a surface structure in an area of the at least one flow channel.

Chip breaking features may be arranged in radial reliefs of a rotary cutting tool. The chip breaking features create gaps or voids in the otherwise continuous cutting edge, resulting in otherwise continuous chips being cut into discrete chips. The chip breaking features may be angled so as to define a secondary cutting edge. Depending on the angle at which the chip breaking features are angled, the secondary cutting edges may partially or completely close the gaps or voids in the cutting edge. Closing the gaps or voids in the cutting edge ensures that each blade removes nearly all material so the following blade does not have to clean up.

A rotary cutting tool is provided that includes a shank and a body. The body extends axially outwardly from the shank, and has a plurality of first teeth and a plurality of second teeth. The first and second teeth are alternately arranged and spaced apart from one another around a circumference. Each first tooth includes a primary cutting edge disposed at a primary angle relative to the rotational axis and a tertiary cutting edge disposed at a tertiary angle relative to the rotational axis. Each second tooth includes a secondary cutting edge disposed at a secondary angle relative to the rotational axis. The secondary cutting edge is disposed axially between the primary cutting edge and the tertiary cutting edge.