Abstract: In an inner pipe assembly step, sheet-metal-made inner-pipe divided bodies and a cast inner-pipe divided body are connected to assemble an inner pipe. In a center flange connecting step, the sheet-metal-made inner-pipe divided bodies are connected to a center flange. In an outer pipe connecting step, an outer pipe covering the inner pipe is connected to the center flange and an exhaust-air-inlet-side flange. In a masking step, at least one of: a connected portion between the sheet-metal-made inner-pipe divided bodies and the cast inner-pipe divided body; or an opening portion between the outer pipe and the inner pipe is sealed. In a cutting machining step, an inner wall surface of the cast inner-pipe divided body facing the turbine wheel is subjected to a cutting machining after the masking step.

Abstract: In an inner pipe assembly step, sheet-metal-made inner-pipe divided bodies and a cast inner-pipe divided body are connected to assemble an inner pipe. In a center flange connecting step, the sheet-metal-made inner-pipe divided bodies are connected to a center flange. In an outer pipe connecting step, an outer pipe covering the inner pipe is connected to the center flange and an exhaust-air-inlet-side flange. In a masking step, at least one of: a connected portion between the sheet-metal-made inner-pipe divided bodies and the cast inner-pipe divided body; or an opening portion between the outer pipe and the inner pipe is sealed. In a cutting machining step, an inner wall surface of the cast inner-pipe divided body facing the turbine wheel is subjected to a cutting machining after the masking step.

Abstract: A cylindrical internal surface processing method comprises forming a cylinder bore, roughening an upper section of the bore, depositing coating onto the bore, and machining a lower section of the bore and the coating. The forming of the cylinder bore includes forming the upper and lower sections with the lower section being axially spaced from the upper section and having an axial length greater than zero. The roughening creates a roughened surface such that a radially innermost edge of the roughened surface has an internal diameter smaller than an internal diameter of the lower section. The coating is deposited to cover the upper section and at least a portion of the lower section. The machining forms a tapered portion and a cylindrical portion, a radially outermost edge of the cylindrical portion having an internal diameter larger than that of a radially outermost edge of the roughened surface.

Abstract: A cylindrical internal surface processing method comprises forming a cylinder bore, roughening an upper section of the bore, depositing coating onto the bore, and machining a lower section of the bore and the coating. The forming of the cylinder bore includes forming the upper and lower sections with the lower section being axially spaced from the upper section and having an axial length greater than zero. The roughening creates a roughened surface such that a radially innermost edge of the roughened surface has an internal diameter smaller than an internal diameter of the lower section. The coating is deposited to cover the upper section and at least a portion of the lower section. The machining forms a tapered portion and a cylindrical portion, a radially outermost edge of the cylindrical portion having an internal diameter larger than that of a radially outermost edge of the roughened surface.

Abstract: A thermally sprayed coating is deposited onto a cylindrical internal surface of a base member after a rough surface has been formed on the cylindrical internal surface. The tapered surface is configured such that the internal diameter of the axial end portion is larger than the internal diameter of the remaining portions of the cylinder bore internal surface. After the tapered surface is formed, the thermally sprayed coating is honed. This method prevents exfoliation of a thermally sprayed coating at an end portion of a cylindrical internal surface in a situation where honing or another mechanical finishing process is applied to the thermally sprayed coating after the coating is formed on the cylindrical internal surface.

Abstract: In a coarse honing step in a section (101), a honing head (15) provided with coarse honing hones (17) is inserted into a cylinder bore (13) of a cylinder block (11), the honing head 15 is rotated while axially moving it, and the inner peripheral surface of the cylinder bore (13) is thereby ground. In the next idling step in a section (102), the cylinder block (11) is left as it is for (60) seconds to generate a springback (S). In a subsequent finishing honing step in a section (103), a honing head (21) provided with finishing honing hones (19) is inserted into the cylinder bore (13), the honing head (21) is rotated in a reverse direction to a rotational direction in the coarse honing step while axially moving it, and the inner peripheral surface of the cylinder bore (13) is thereby ground. Further, a coolant is supplied to the sections of the coarse honing step, the idling step, and the finishing honing step from coolant nozzles (23), (25), and (27), respectively, using a common coolant supply source (29).

Abstract: In a coarse honing step in a section (101), a honing head (15) provided with coarse honing hones (17) is inserted into a cylinder bore (13) of a cylinder block (11), the honing head 15 is rotated while axially moving it, and the inner peripheral surface of the cylinder bore (13) is thereby ground. In the next idling step in a section (102), the cylinder block (11) is left as it is for (60) seconds to generate a springback (S). In a subsequent finishing honing step in a section (103), a honing head (21) provided with finishing honing hones (19) is inserted into the cylinder bore (13), the honing head (21) is rotated in a reverse direction to a rotational direction in the coarse honing step while axially moving it, and the inner peripheral surface of the cylinder bore (13) is thereby ground. Further, a coolant is supplied to the sections of the coarse honing step, the idling step, and the finishing honing step from coolant nozzles (23), (25), and (27), respectively, using a common coolant supply source (29).