Micro Power Unit,Electric Hydraulic Pump Unit,Mini Electric Hydraulic Pump Unit,Small Hydraulic Power Unit Huai'an Youbang Hydraulic Machinery Co., Ltd. , https://www.yb-hydraulic.com (1) High hobbing speed Generally, in the dry hobbing process, the linear speed of the high-speed steel hob required for the coating (TiAlN) reaches 180m/min or even higher; for the hard alloy steel rolling The knife speed requirement is 300 m/min. In order to achieve this high-speed hobbing process, the tool spindle can generally be realized by means of an electric spindle; for the work table, a newly designed gear drive system with automatic clearance elimination is used instead of the conventional worm and worm gear transmission system. LIEBHERR, GLEASON The company's small and medium-sized high-speed gear hobbing machine worktable has adopted torque servo motor technology, and the worktable speed has reached 800 r/min or more.
(2) Rapid separation of chips Because of the high temperature, if the chips cannot rapidly separate from the tools, workpieces, and machine tools, they will easily cause thermal deformation and affect the machining accuracy. Therefore, iron chips must be quickly and effectively eliminated. In dry hobbing, high-speed hobbing by a hob is generally used to quickly remove iron chips from the tool and workpiece. Many companies have also proposed some improvements to the chip evacuation problem, such as the use of gravity to speed up the removal of iron scraps, and to avoid the direct falling of iron scraps on the workbench, and then to assist the high-pressure cold wind to achieve the effect of rapid and effective chip removal. Some companies also use stainless steel heat shields, on the one hand, stainless steel surface is smooth, easy to remove iron, on the other hand, stainless steel heat transfer coefficient is small, reducing the iron heat transfer to the table and the bed.
(3) High-speed hobs The development of hob materials for dry hobbing uses carbide steels in the early stages. However, due to the high cost of hard alloy steel hobs, the powder metallurgy high-speed steel hobs developed in recent years and TiAlN coated high-speed steel hobs have a tendency to replace carbide steel hobs for dry hobbing. Liebherr's research report on dry-cutting of carbide blades, dry-rolling of HSS-PM, and hobbing of Conv.HSS The time and processing costs are compared. The comparative analysis results show that the dry hobbing has shorter processing time and lower cost compared to conventional machining; the powder metallurgy high-speed steel hob has even better dry hobbing effect than the hard alloy steel hob. .