To obtain a forged product having an excellent dimensional precision by preventing the flow of a metal from hindering due to the back pressure of the air confined in cavities.
Single or plural air vents 11, 21 extending in parallel to the forging direction P are formed in the surface facing cavities 30 of a male die 10 and/or a female die 20. The hole diameter of air vents 11, 21 is preferably specified to be 1mm or more to the wall thickness or less of the product. The fringe part meshing with the forged product is also allowed to provide in the punch part of the male die 10. The air confined in recessed part 31 and groove part 32 of cavities 30 is escaped via air vents at the time of forging with this die, the metal is made to flow in every corner of cavities 30, whereby the forged product without defective shapes and insufficient wall thickness is produced.
| JPH08326677 | HERMETIC COMPRESSOR |
| JPS58200092 | SCROLL FLUID MACHINE |
| JP2009236000 | AIR COMPRESSOR |
YAMADA TATSU
SUZUKI MINORU
KATSUMATA SUMIO
HOSONO YOJI
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