Abstract: A novel method of manufacturing a turbine frame for rotatably holding adjustable blades in a VGS turbocharger is provided, which method is capable of manufacturing the turbine frame while almost eliminating a time-consuming cutting operation, whereby mass production of the turbine frame and the like can be realized. The method includes: a blank which is punched out from a metal material having a substantially constant thickness in such a manner as to integrally include a boss forming portion (24a) and a flange forming portion (23a) is used as a shaped material (W) serving as an original member for the turbine frame; when the shaped material (W) is processed, the boss forming portion (24a) is formed into a projecting state by a press forging tool; receiving holes for rotatably holding the respective adjustable blades are formed in the flange forming portion (23a) by punching; and when the shaped material (W) is processed, some or all of the manufacturing processes are carried out in a warm condition.

Abstract: A shaft portion is processed to have a desired diametrical thickness by rolling in place of cutting so that a cutting operation requiring much time may be eliminated from a manufacturing process of the adjustable blade. A shaft elongation and a sharp edge caused by the rolling can be inhibited to thereby eliminate an additional cutting operation conventionally performed for correcting the shaft elongation and the sharp edge. In particular, a metal shaped material for an adjustable blade integrally provided with a blade portion and a shaft portion is formed to have a shape and a size close to those of the desired adjustable blade. In forming the shaft portion, a shaft portion forming section of the shaped material is rolled to have a desired diametrical thickness.

Abstract: A manufacturing method based on a plastic working technique which can eliminate cutting and welding as much as possible in manufacturing an adjustable blade incorporated in a VGS turbocharger. In the method a blank is punched out from a metal material having a substantially constant thickness to be a shaped material (W) as a starting form for an adjustable blade (1); thereafter, the shaped material (W) is compressed between a pair of opposed dies to form a blade portion (11), a shaft portion (12) and the like having desired shapes; thereafter a non-product portion protruding from a product portion is trimmed; then the shaft portion (12) is rolled by pressing the shaft portion (12) of the shaped material (W) against a pair of dies to have a desired diametrical thickness and a near net shape having a shape and dimensions thereof made close to the aimed at adjustable blade.

Abstract: A novel exhaust gas guide assembly with an improved high-temperature sliding wear resistance, oxidation resistance, high-temperature strength or the like for a VGS turbocharger is provided. The invention is characterized in that a surface modification is applied to a component member of the exhaust gas guide assembly (A), such as adjustable blades (1), a turbine frame (2), a blade adjusting mechanism (3), or the like.

Abstract: A novel manufacturing method is provided which can actually achieve mass production of an adjustable blade and a VGS turbocharger having the adjustable blades incorporating therein, wherein a shaft portion is processed to have an aimed at diametrical thickness by rolling in place of cutting so that a cutting operation requiring much time may be eliminated as much as possible from a manufacturing process of the adjustable blade, and wherein a shaft elongation and a sharp edge caused by the rolling can be extremely inhibited to thereby eliminate an additional cutting operation conventionally performed for correcting the shaft elongation and the sharp edge.

Abstract: A manufacturing method based on a plastic working technique which can eliminate cutting and welding as much as possible in manufacturing an adjustable blade incorporated in a VGS turbocharger is provided.

Abstract: A novel method of manufacturing a component member of a VGS turbocharger is provided, which method enables, when manufacture of the component member is performed mainly by press working using a die, the press working to be efficiently performed because of various engineering improvements applied thereto in accordance with working techniques and a formed shape.

Abstract: A novel method of manufacturing a turbine frame for rotatably holding adjustable blades in a VGS turbocharger is provided, which method is capable of manufacturing the turbine frame while almost eliminating a time-consuming cutting operation, whereby mass production of the turbine frame and the like can be realized.