... aluminum, copper, zinc,etc. 3.melting, holding Big well type H/T furnace1. heat energy :electricity2.popuse:mainly used to some big ... work pieces,such as shafts ,rods and gears for H/T of quenching ,temping ,forging,annealing ,carbon penetrating etc3.temperature control ... layers blast; 5)No obvious vibration and turbulence; Big well type H/T furnace