A method for manufacturing a bracelet made of synthetic material for watches or jewellery including at least one strand, the method including a step of making, by moulding or extrusion, a band of synthetic material intended to form at least one strand, the method being wherein it then includes a step of chemical mechanical polishing the band. A bracelet made of synthetic material for watches or jewellery includes at least one strand formed of an extruded or injection moulded band, wherein at least one strand has a roughness Rp less than or equal to 3 m and preferably less than or equal to 2 m.

A method, performed by a centrifuge, for treating toughness and hardness of drill bit buttons is provided. The centrifuge comprises a chamber formed by a stationary side wall and a bottom which is rotatable around a rotation axis, the bottom comprising one or more protrusions which at least partly extends between the rotation axis and the side wall, the side wall comprising at least six pushing elements arranged around a periphery of the side wall. The method comprises rotating, by rotation of the bottom with the protrusions, the drill bit buttons around the rotation axis, pushing, by the pushing elements, the drill bit buttons from the side wall during the rotation of the bottom, collectively forming the drill bit buttons into a torus shape at the bottom of the chamber for inducing collisions between the drill bit buttons, thereby treating the toughness and hardness of the drill bit.

A method, performed by a centrifuge, for treating toughness and hardness of drill bit buttons is provided. The centrifuge comprises a chamber formed by a stationary side wall and a bottom which is rotatable around a rotation axis, the bottom comprising one or more protrusions which at least partly extends between the rotation axis and the side wall, the side wall comprising at least six pushing elements arranged around a periphery of the side wall. The method comprises rotating, by rotation of the bottom with the protrusions, the drill bit buttons around the rotation axis, pushing, by the pushing elements, the drill bit buttons from the side wall during the rotation of the bottom, collectively forming the drill bit buttons into a torus shape at the bottom of the chamber for inducing collisions between the drill bit buttons, thereby treating the toughness and hardness of the drill bit.

A method for outer surface finishing of a workpiece may include coaxially placing the workpiece inside a vessel. The exemplary vessel may include at least one baffle that may radially extend from an inner wall of the vessel toward the outer surface of the workpiece. The exemplary method may further include pouring an abrasive medium inside the vessel, rotating the abrasive medium about the longitudinal axis in a first direction within the vessel relative to the outer surface of the workpiece by rotating the vessel about the longitudinal axis, and concurrently rotating the workpiece within the vessel about the longitudinal axis in a second direction, the second direction being opposite the first direction.

Disclosed herein is a method for inner surface finishing of a workpiece, in which the inner surface of the workpiece defines an opening with axial symmetry around the longitudinal axis of the workpiece. The method may include the following steps. An abrasive medium may be poured inside the opening; urging the abrasive medium to rotate about the longitudinal axis, thereby imposing a centrifugal force on the abrasive medium to accelerate the abrasive medium outwards from the center of rotation towards the inner surface of the opening, where the abrasive medium impacts the inner surface of the opening; and the workpiece may be rotated about the longitudinal axis in a direction opposite the first direction, concurrently.

A barrel polishing apparatus has a barrel tank. The barrel tank includes a cylindrical fixed tank having a center axis and a rotary disk provided to cover a bottom portion of the fixed tank and rotatable about the center axis. The barrel polishing apparatus further includes a tilting mechanism. The tilting mechanism has a tilting shaft extending in a horizontal direction to tilt the barrel tank around the tilting shaft. The tilting shaft is disposed closer to the upper edge of the fixed tank than a centroidal line extending parallel to the tilting shaft and passing through the center of gravity of the barrel tank when viewed from a direction parallel to an extending direction of the tilting shaft.

A barrel polishing apparatus has a barrel tank. The barrel tank includes a cylindrical fixed tank having a center axis and a rotary disk provided to cover a bottom portion of the fixed tank and rotatable about the center axis. The barrel polishing apparatus further includes a tilting mechanism. The tilting mechanism has a tilting shaft extending in a horizontal direction to tilt the barrel tank around the tilting shaft. The tilting shaft is disposed closer to the upper edge of the fixed tank than a centroidal line extending parallel to the tilting shaft and passing through the center of gravity of the barrel tank when viewed from a direction parallel to an extending direction of the tilting shaft.

A method, performed by a centrifuge, for treating toughness and hardness of drill bit buttons is provided. The centrifuge comprises a chamber formed by a stationary side wall and a bottom which is rotatable around a rotation axis, the bottom comprising one or more protrusions which at least partly extends between the rotation axis and the side wall, the side wall comprising at least six pushing elements arranged around a periphery of the side wall. The method comprises rotating, by rotation of the bottom with the protrusions, the drill bit buttons around the rotation axis, pushing, by the pushing elements, the drill bit buttons from the side wall during the rotation of the bottom, collectively forming the drill bit buttons into a torus shape at the bottom of the chamber for inducing collisions between the drill bit buttons, thereby treating the toughness and hardness of the drill bit.

A method, performed by a centrifuge, for treating toughness and hardness of drill bit buttons is provided. The centrifuge comprises a chamber formed by a stationary side wall and a bottom which is rotatable around a rotation axis, the bottom comprising one or more protrusions which at least partly extends between the rotation axis and the side wall, the side wall comprising at least six pushing elements arranged around a periphery of the side wall. The method comprises rotating, by rotation of the bottom with the protrusions, the drill bit buttons around the rotation axis, pushing, by the pushing elements, the drill bit buttons from the side wall during the rotation of the bottom, collectively forming the drill bit buttons into a torus shape at the bottom of the chamber for inducing collisions between the drill bit buttons, thereby treating the toughness and hardness of the drill bit.

The invention discloses a seamless flowing type finishing machine, comprising a supporting frame; the supporting frame is provided with a lower container, an upper container and a tray; the tray is movably connected with the lower container. A plurality of bolts is arranged between the lower container and the upper container for connection; springs are arranged at the connections of the bolts. The upper edge of the tray extends to the lower edge of the upper container; with the elastic force of the springs, the lower edge of the upper container clings to the upper edge of the tray so as to form a seamless connecting structure; a water outlet is arranged on the tray. A water-filling nozzle is arranged on the sidewall of the lower container. The seamless flowing type finishing machine disclosed by the invention can be used for processing of various ultra-small parts.