... furnace, 2.for 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 ... corrosive gas layers blast; 5)No obvious vibration and turbulence; Big well type H/T furnace