Skiving or scarring is the process of cutting material into slices, usually metal , but also leather or laminates . Skiving is used instead of rolling to shape the material when the material is not to be hardened , or leaving small pieces of metal afterward which is common in cold rolling processes.
In metalworking, skewing can be used to remove a thin dimension of a material or to create thin slices in an existing material, such as heat sinks where a large amount of surface area is required relative to the volume of the metal piece.
The process involves transferring the bar to a precision-sized precision-profiled slotted tool or past plain cutting tool . Tools are typically made of tungsten carbide -based compounds. In early machines, it was necessary to precisely position the bar relative to the cutting tool, but newer machines use a temporary suspension technique that enables the tool to be detected by material contact. This reciprocal starting position allows a differential of up to approximately 12 mm (0.47 in) followed by flexible automatic engagement. Products using this technology can be directly applied to automotive seatbelt springs, large power transformer winding strips, rotogravure plates, cable and hose clamps ,There are gas tank straps and window counterbalance springs. Products using the indirect process are tubes and pipes where the edge of the strip is precisely beveled before being bent into a tubular form and the seam is welded . Beveled edges enable pinhole free welds.
A minimum material feed rate is required for successfully cutting skiving. Skiving tools can be vibrated at a high frequency to increase the relative motion between the tool and the workpiece, for metal planing or at speeds as low as about 10 m/s (33 ft/min).
Another metal skiving application is for hydraulic cylinders , where a round and smooth cylinder bore is required for proper actuation. On a round tool many skiving knives pass through a bore to create a perfectly round hole. Often, the second operation of roller burning is after cold-working the surface to a mirror finish . This process is common among manufacturers of hydraulic and pneumatic cylinders. [1] Compared to honing, skiving and roller burning are faster and generally provide more precise tolerances and better inside surface finish control. [2]
Skiving can be applied to gear cutting , where the internal gears are rotated with a rotary cutter ( shaped or broached ) in a process similar to hobbing of the external gear . [3]
Heat sinks
Skiving is also used for manufacturing heat sinks for PC cooling products . A PC cooler made by Skiving has the advantage that the heat sink base and fin are made from a single piece of material (copper or aluminum), providing better heat dissipation and heat transfer from base to fin. Additionally, the skiving process also increases the roughness of the wings. Unlike the underside of the heat sink, which must be smooth for maximum contact area with the heat source, the fins benefit from this roughness as it increases the surface area of the fins over which the heat in the air can be dissipated. Is. Fins can be made much thinner and closer together than extrusion or formed sheet processes, providing high-performance applications for water cooling.Could offer more heat transfer to the waterblock .