METHOD FOR MANUFACTURING OILLESS BUSHING

摘要

PROBLEM TO BE SOLVED: To reduce mechanical equipment and man-hours and to drastically reduce a manufacturing cost by dispensing with blank working and perforating after casting of the conventional green sand mold casting method. SOLUTION: A casting of an oilless bushing is formed by a lost foam pattern casting method using a cylindrical lost foam pattern made of a foamed resin having many through-holes at its peripheral wall and graphite is packed into the through-holes disposed at the peripheral wall of the casting and the casting packed with the graphite is subjected to finishing, by which the oilless bushing is formed. The graphite having annular grooves at its peripheral surface center is packed into the through-holes of the cylindrical lost foam pattern and the casting of the oilless bushing is manufactured by the lost foam pattern casting method using the lost foam pattern packed with this graphite and the oilless bushing is formed by finishing this casting.