PURPOSE: To grind the inner surface of long pipe in full length evenly and smoothly, expanding emery cloth wound on the outer surface of the grinding head partially and radially to push to the inner surface of pipe by compressed fluid, in the inner surface grinder for small sized long pipe.
CONSTITUTION: After emery cloth 24 has been wound on the outer surface of outer sleeve 13 of grinder head 4, reversing grinder head 4 to the initial grinding end of pipe to be ground with the bar feeding equipment, positioning window 23 of grinder head 4 in the retreated position from the pipe end to be ground. Next, compressed fluid is ejected from nozzle 19 through supply hose 9, supporting lever 3 of inner pipe bar 6 and inner pipe 14. Elastic expansion element 20 installed on the outer surface of inner pipe is pressurized from inside by this ejection, a part of elastic expansion element 20 under window 23 of outer surface 13 is expanded outward from window 23. The circumference of emery cloth 24 wound on the outer pipe 13 is expanded radially by expansion, pushing it to the inner surface of pipe to be ground, the inner surface in full length is ground evenly.
TAKIZAWA HIROYASU
MARUYAMA RIYOUJI
KANEDA MORIMASU
MATSUSHITA AKIYOSHI
