MANUFACTURE OF VENT PLUG FOR HYDRAULIC MACHINE

摘要

PURPOSE:To increase productivity and to reduce production costs of vent plugs by forming a recess on the top periphery of a plug by pressing and an axially directed hole communicating with the recess by drilling. CONSTITUTION:The recess 24 in the radial direction is formed on the periphery of a valve part 20 of a semi-manufactured plug 10 by pressing. The hole 28 is formed by drilling from the bottom to the top of the plug 10 in the axial direction with a length and a diameter communicating with the recess 24. The method mass-products the vent plug for hydraulic machines with a short machining time.