Abstract: [Task] To provide a method that makes it possible to easily, inexpensively and accurately manufacture a machined part with a simple configuration and an excellent strength. [Means for Solution] In a method for manufacturing a machined part according to the invention, a dislocation is partially introduced (S3), through shot peening, only into a surface layer of a raw material 1 in a region 1a to be machined, graphite is partially deposited (S4), through heating, only in the surface layer of the region 1a to be machined, and then, the surface layer of the region 1a where graphite is deposited is removed, through machining (S5), only by an amount corresponding to a working margin 1c, thereby manufacturing a machined part 1?.

Abstract: The problem of the present invention involves providing a gear that has high tooth-root bending strength and for which there is no chipping of the tips of the teeth. Accordingly, the surface of the gear is carburized and the gear is strengthened by imparting residual stress, with the residual stress in the region with a surface depth of 5 ?m to 20 ?m being ?1000 MPa or less, and the residual stress in the region with a surface depth of 50 ?m to 150 ?m being ?1000 MPa or greater.

Abstract: [Task] To provide a method that makes it possible to easily, inexpensively and accurately manufacture a machined part with a simple configuration and an excellent strength. [Means for Solution] In a method for manufacturing a machined part according to the invention, a dislocation is partially introduced (S3), through shot peening, only into a surface layer of a raw material 1 in a region 1a to be machined, graphite is partially deposited (S4), through heating, only in the surface layer of the region 1a to be machined, and then, the surface layer of the region 1a where graphite is deposited is removed, through machining (S5), only by an amount corresponding to a working margin 1c, thereby manufacturing a machined part 1?.

Abstract: The problem of the present invention involves providing a gear that has high tooth-root bending strength and for which there is no chipping of the tips of the teeth. Accordingly, the surface of the gear is carburized and the gear is strengthened by imparting residual stress, with the residual stress in the region with a surface depth of 5 ?m to 20 ?m being ?1000 MPa or less, and the residual stress in the region with a surface depth of 50 ?m to 150 ?m being 1000 MPa or greater.

Abstract: Disclosed is an exhaust system part having a high corrosion resistance, an EGR cooler using the exhaust system part, and a method of nitriding the exhaust system part. The exhaust system part made of a stainless steel and having an exhaust gas of an internal combustion engine flow therein, includes an upstream side end portion through which the exhaust gas is introduced, a downstream side end portion through which the exhaust gas is discharged, and a wall portion formed in an annular shape extending in the direction of the exhaust gas flow and disposed between the upstream side end portion and the downstream side end portion, in which a chromium oxide nitride film consisting of CrOxNy is formed on the inner peripheral surface of the wall portion.

Abstract: The problem of the present invention involves providing a gear that has high tooth-root bending strength and for which there is no chipping of the tips of the teeth. Accordingly, the surface of the gear is carburized and the gear is strengthened by imparting residual stress, with the residual stress in the region with a surface depth of 5 ?m to 20 ?m being ?1000 MPa or less, and the residual stress in the region with a surface depth of 50 ?m to 150 ?m being ?1000 MPa or greater.

Abstract: To provide a method of manufacturing a carburized part contributable to cost reduction, a portion intended for a non-carburizing portion is treated to a surface roughness corresponding to Rz 50 like a first work surface and a portion intended for a carburizing portion is treated to a surface roughness corresponding to Rz 1.5 like a second work surface.

Abstract: Provided is a method for manufacturing a blasting material for shot peening with which a reliably high level of hardness can be achieved while preventing an increase in the material cost. Quenchable steel is used as a material in a blasting material manufacturing step (S10). After granules (4) which are quenched by means of a water atomization method are formed in a quenching step (S20), the granules (4) are tempered inside a heating furnace (5) at a prescribed temperature (from 130-230° C., and preferably from 160-230° C.) For a prescribed amount of time in a tempering step (S30). A work hardening treatment is applied in a work hardening step (S40) wherein the granules (4) are blasted/bombarded onto a target material (7) to apply stress to the granules (4) using an apparatus for shot peening (6).

Abstract: To provide a method of manufacturing a carburized part contributable to cost reduction, a portion intended for a non-carburizing portion is treated to a surface roughness corresponding to Rz 50 like a first work surface and a portion intended for a carburizing portion is treated to a surface roughness corresponding to Rz 1.5 like a second work surface.

Abstract: Provided are a steel having a non-magnetic portion, which can be applied to the steel of the remaining portion irrespective of the material and which has a structure of a short treating time required and a determined depth direction, its manufacturing method, and a revolving electric core. There is prepared an electromagnetic steel sheet having a recessed groove. A two-layered chip of a modifier metal foil and a stainless steel foil is so set in the groove of the electromagnetic steel sheet that the electromagnetic steel sheet and the stainless steel foil have surfaces of the same height. The modifier metal foil is melted when electric current is applied under pressure. When this pressing and current applying is continued, inner sides of the electromagnetic steel sheet and the stainless steel foil contacting the modifier metal foil are melted to form a nonmagnetic alloy layer in the region excepting the surface portions of an electromagnetic steel sheet layer and a stainless steel layer.

Abstract: A method and apparatus of manufacturing an endless metallic belt adjusts a circumferential length of the belt by subjecting the endless metallic belt to a shot peening treatment. For example, by measuring the circumferential length prior to the shot peening treatment and determining the condition of the shot peening treatment on the basis of the measured length, and/or by measuring the circumferential length during the shot peening treatment and terminating the shot peening treatment on the basis of the measured length.

Abstract: An endless metallic belt has at its outer peripheral surface a layer provided with a compressive residual stress by shot peening, and also has at its inner peripheral surface a layer provided with a compressive residual stress by shot peening. In a method for manufacturing the endless metallic belt, both outer and inner peripheral surfaces of the endless metallic belt are subjected to shot peening, wherein the inner peripheral surface is shot peened prior to the outer peripheral surface. The method produces an endless metallic belt having its fatigue strength improved without suffering any significant deformation.

Abstract: A method and apparatus of manufacturing an endless metallic belt adjusts a circumferential length of the belt by subjecting the endless metallic belt to a shot peening treatment. For example, by measuring the circumferential length prior to the shot peening treatment and determining the condition of the shot peening treatment on the basis of the measured length, and/or by measuring the circumferential length during the shot peening treatment and terminating the shot peening treatment on the basis of the measured length.

Abstract: An endless metallic belt has at its outer peripheral surface a layer provided with a compressive residual stress by shot peening, and also has at its inner peripheral surface a layer provided with a compressive residual stress by shot peening. In a method for manufacturing the endless metallic belt, both outer and inner peripheral surfaces of the endless metallic belt are subjected to shot peening, wherein the inner peripheral surface is shot peened prior to the outer peripheral surface. The method produces an endless metallic belt having its fatigue strength improved without suffering any significant deformation.

Abstract: A method of corrugating a metallic pipe which achieves an increase in the limit of tube expansion ratios. First, a heated part is formed by heating a local part of an outer periphery of a pipe in a circumferential direction by a high frequency coil. Next, the heated part is located within a forming surface of a forming die, and an axial compressive stress is applied to the pipe. Thus, the heated part is expanded while restricted by the forming surface. Therefore, even when the axial length of the heated part is increased, formability is stabilized and the tube expansion ratio can be raised.

Abstract: The present invention can provide a method and an apparatus for bending a pipe whose bending cross section has reduced compressed ratio, reduced reduction ratio of area and reduced reduction in thickness and in which bending can be conducted at the desired curvature. In the present invention, both edges of the pipe bending portion are arrested and grasped, a center of one bending edge is set to be the axis and a revolution axis is amounted on it, a rotation axis is mounted at a center of the other bending edge and gears are installed on the revolution axis and the rotation axis so as to engage each other so that the driving is driven to the gear on the rotation axis. The rotation axis revolves having the radius to be the distance from the rotation axis to the revolution axis and at the same time the rotation axis rotates on its axis having the radius of the gear in response to the revolution angle.

Abstract: In a method and apparatus for manufacturing a corrugated tube, a tube is clamped by a pair of spaced apart chucks. A local portion of the tube is softened. The chucks are moved in the same direction such that the trailing or rearward chuck moves farther than the leading or forward chuck, thereby imparting an axially compressive force on the tube. Accordingly, a bulge is formed at the softened portion of the tube. The heating and compression cycle may be performed several times to obtain a corrugated tube having a plurality of bulges or waves formed therein.