METHOD FOR PRODUCING ENGINE VALVE IN WHICH SODIUM METAL IS SEALED

• Main Authors: MORII HIROKAZU, MARUYAMA KAZUTAKA, YOSHIMURA HYOJI
• Format: Patent
• Language: English
• Published: 24.01.2013
• Subjects: BLASTING; COMBINED OPERATIONS; CYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES; ENGINE PLANTS IN GENERAL; HEATING; LIGHTING; MACHINE TOOLS; MACHINES OR ENGINES IN GENERAL; MAKING FORGED OR PRESSED METAL PRODUCTS, e.g. HORSE-SHOES,RIVETS, BOLTS OR WHEELS; MECHANICAL ENGINEERING; MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVINGMATERIAL; METAL-WORKING NOT OTHERWISE PROVIDED FOR; OTHER WORKING OF METAL; PERFORMING OPERATIONS; PUNCHING METAL; STEAM ENGINES; TRANSPORTING; UNIVERSAL MACHINE TOOLS; WEAPONS; WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS ORPROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL

Provided is a method for producing an engine valve by subjecting a stem portion having a hollow part to a drawing treatment using a series of dies such that the outer diameter and inner diameter of the stem portion become smaller in steps and the stem portion is thereby molded to the desired size, whereby, after the stem portion has been subjected to the drawing treatment until the inner diameter of the hollow part of the stem portion has reached a specific size, sodium metal in the form of a solid block is introduced to the hollow part of the stem portion, and a protective agent made from solid paraffin or naphthalene is also introduced to the hollow part of the stem portion such as to foam a barrier between the sodium metal and the atmosphere, after which the stem portion is further subjected to a cold drawing treatment.