A one-piece axle and a method of manufacture. The method may include providing a one-piece axle blank that has a shaft and a flange. The shaft may have a hole that may extend along an axis. The flange may extend radially outward from an end of the shaft. The shaft may be radially forged against a first mandrel to axially elongate the shaft.

A one-piece axle and a method of manufacture. The method may include providing a one-piece axle blank that has a shaft and a flange. The shaft may have a hole that may extend along an axis. The flange may extend radially outward from an end of the shaft. The shaft may be radially forged against a first mandrel to axially elongate the shaft.

A one-piece axle and a method of manufacture. The method may include providing a one-piece axle blank that has a shaft and a flange. The shaft may have a hole that may extend along an axis. The flange may extend radially outward from an end of the shaft. The shaft may be radially forged against a first mandrel to axially elongate the shaft.

A hollow forging process for main shaft of large wind turbine generator, wherein, comprising the following steps as: the first step of cutting off the dead head and the bottom of an ingot; the second step of upsetting and punching a hole; the third step of drawing-out; and the fourth step of local upsetting, drawing-out and shaping-up. In the fourth step, the forged piece is shaped up by local upsetting and drawing-out through a turnplate. The hollow forging process for main shaft created by the invention can save the costs for enterprise to purchase large equipment and makes it possible to forge the main shaft of large wind turbine generator with a free forging oil press with a smaller size.

A hollow forging process for main shaft of large wind turbine generator, wherein, comprising the following steps as: the first step of cutting off the dead head and the bottom of an ingot; the second step of upsetting and punching a hole; the third step of drawing-out; and the fourth step of local upsetting, drawing-out and shaping-up. In the fourth step, the forged piece is shaped up by local upsetting and drawing-out through a turnplate. The hollow forging process for main shaft created by the invention can save the costs for enterprise to purchase large equipment and makes it possible to forge the main shaft of large wind turbine generator with a free forging oil press with a smaller size.

A method for manufacturing a tubular member has: a step of disposing a steel pipe which is a material in an outer the having an inner surface having the same shape as an outer form of the tubular member with at least a part of the steel pipe being separated from the inner surface; and a step of compressing the steel pipe in the axial direction by decreasing a relative distance between a pair of pressurizing dies that respectively abut both end surfaces of the steel pipe in the axial direction in a state where a core the portion having an outer surface shape that is the same as inner surface shapes of the both end portions of the tubular member in the axial direction is inserted between the pair of pressurizing dies with at least a pan of the core the portion being separated from the inner surface of the steel pipe.

A method for manufacturing a tubular member has: a step of disposing a steel pipe which is a material in an outer the having an inner surface having the same shape as an outer form of the tubular member with at least a part of the steel pipe being separated from the inner surface; and a step of compressing the steel pipe in the axial direction by decreasing a relative distance between a pair of pressurizing dies that respectively abut both end surfaces of the steel pipe in the axial direction in a state where a core the portion having an outer surface shape that is the same as inner surface shapes of the both end portions of the tubular member in the axial direction is inserted between the pair of pressurizing dies with at least a pan of the core the portion being separated from the inner surface of the steel pipe.

The invention sets out a method for simply producing components which are suitable for use under high loads and risks of wear and which have a core portion which consists of a metal material and a wear-resistant layer on a peripheral surface of the core portion. To this end, there is provided according to the invention a) a core portion blank which consists of the metal material and whose dimension in a first spatial direction is greater than the desired finished dimension of the core portion of the component in the relevant spatial direction and whose dimension in a second spatial direction is smaller than the desired finished dimension of the core portion of the component in this second spatial direction; b) there is applied a material which forms the wear-resistant layer to the peripheral surface in such a manner that the material and the core portion blank form a stable composite body; and c) the composite body is shaped to form the component by the composite body being extended in the direction of the second spatial direction and being compressed in the direction of the first spatial direction until the dimensions thereof in the spatial directions at least correspond to the desired finished dimensions of the component in these spatial directions and the wear-resistant material is present on a peripheral surface of the component. Optionally, finishing processing of the component may follow.

The invention sets out a method for simply producing components which are suitable for use under high loads and risks of wear and which have a core portion which consists of a metal material and a wear-resistant layer on a peripheral surface of the core portion. To this end, there is provided according to the invention a) a core portion blank which consists of the metal material and whose dimension in a first spatial direction is greater than the desired finished dimension of the core portion of the component in the relevant spatial direction and whose dimension in a second spatial direction is smaller than the desired finished dimension of the core portion of the component in this second spatial direction; b) there is applied a material which forms the wear-resistant layer to the peripheral surface in such a manner that the material and the core portion blank form a stable composite body; and c) the composite body is shaped to form the component by the composite body being extended in the direction of the second spatial direction and being compressed in the direction of the first spatial direction until the dimensions thereof in the spatial directions at least correspond to the desired finished dimensions of the component in these spatial directions and the wear-resistant material is present on a peripheral surface of the component. Optionally, finishing processing of the component may follow.

A hollow forging process for main shaft of large wind turbine generator, wherein, comprising the following steps as: the first step of cutting off the dead head and the bottom of an ingot; the second step of upsetting and punching a hole; the third step of drawing-out; and the fourth step of local upsetting, drawing-out and shaping-up. In the fourth step, the forged piece is shaped up by local upsetting and drawing-out through a turnplate. The hollow forging process for main shaft created by the invention can save the costs for enterprise to purchase large equipment and makes it possible to forge the main shaft of large wind turbine generator with a free forging oil press with a smaller size.