Cryogenic Basics

Cryogenic machining technology uses vacuum jacketed feed lines to deliver small flow rates of liquid nitrogen through the machine, through the spindle (or turret) and through the tool near the cutting edge. Traditional flood coolants have temperatures around +70ºF, cryogenic machining is -321ºF, giving it a -400ºF advantage and allowing for increased processing speed and tool life in tough-to-machine materials. Cryogenic machining delivers liquid nitrogen (LN2) through the tool to cool the cutting edge more efficiently than traditional coolants. The liquid nitrogen evaporates on contact with outside air, leaving the workpiece clean and sterile. Cryogenic machining test results have shown that overall surface integrity and part quality are improved. Parts made using the cryo system have shown reductions in the white/Alpha layer, residual stress, burr formation and surface distortion. Cryogenic machining is best suited for difficult-to-machine materials that typically involve long process times due to slow cutting speeds and poor tool life.