PURPOSE: To perform finish polishing at high smoothness by pressing an abrasive material to a pipe inner surface by magnetic force.
CONSTITUTION: A pair of magnets 4 and 5 are arranged at positions opposing to each other with a pipe 1, a material to be polished, in-between to insert a block-like ferromagnetic body 2 and abrasives 3 into the pipe 1. The abrasives 3 are pressed to the inner surface of the pipe 1 by the ferromagnetic body 2 magnetized in the magnetic fields of the magnets 4 and 5 so as to polish the inner surface. The abrasives 3 in a condition of suspension in liquid is supplied to the inside of the pipe 1. Or, an abrasive cloth/paper or an abrasive nonwoven fabric stuck to the ferromagnetic body 2 can be used instead of the abrasives 3. Consequently, loss due to leakage flux is eliminated, and magnetic force is efficiently consumed for pressing an abrasive material to the inner surface of the pipe 1, allowing finish polishing to high smoothness.
OTSUKA MASAHITO
MATSUBARA SHIGEO
NAKAMOTO KAZUNARI
