ZOLLER offers two types of cooling systems: a non-contact cooling system with air cooling and cooling adapters. Depending on the tool diameter, the cooling time with cooling adapters ranges from 60 to 120 seconds. With »Zstream« air cooling, the process is called “conditioning,” during which the entire tool holder is cooled from the projection to the flange. The conditioning time depends on the diameter of the tool holder and ranges from 3 to 5 minutes.
The concept is simple. Each shrink-fit tool holder is manufactured with an inner diameter that is slightly smaller than the shaft diameter of the cutting tool. An induction heater is used to rapidly heat the nose of the tool holder in order to increase the inner diameter. At this point, the cutting tool can be used in the tool holder. The tool holder is then cooled, causing the diameter to shrink and applying force to the shaft of the cutting tool to hold it in exact position.
When tool holders are shrunk without direct contact, the tool holder system is referred to as a contactless cooling system. This is achieved, for example, using cooling adapters or air cooling.
When tool holders are cooled with a liquid after being heated, this process is called quenching. The tool holder’s lifetime is reduced, and it will rust if it continues to be used with liquids in direct contact with it. The coolant becomes contaminated after a short time and must be replaced; otherwise, it will break down, emit a strong odor, and contain harmful substances that are dangerous to human skin.