... idt ISO 9001:1994 Quality System certified GWBJ Series Medium Frequency Coreless Induction Holding FurnaceMedium Melting Equipment1. ... for pipelining and automatic product line. With the MF equipment, the production quality will be improved. Our MF ... penetrating heating, quenching, pipe bending, vegetating, etc. GWBJ Series Medium-Frequency Coreless Induction Holding Furnace, Medium Melting Equipment