Technical descriptionItem no. 10403107, Revision 12 13 ( 40 )5.3 CoolingLiquid cooling keeps the HF spindle at a constant temperature during opera-tion.Note: Extension of the service life through heat dissipation.Heat is produced during operation of the HF spindle. The temperature of theHF spindle should not exceed + 45° C as this shortens the service life of thebearing.u Check the temperature of the HF spindle on the housing.5.4 Sealing airFor guidelines on air quality,see "Air purity classes (ISO8573-1) [} 24]" section.The sealing air prevents foreign bodies such as chips and liquids (e.g. emul-sions) from entering the HF spindle.Ü Check that air escapes at the front between the housing and the rotatingparts of the HF spindle.5.5 Taper cleaningFor guidelines on air quality,see "Air purity classes (ISO8573-1) [} 24]" section.Taper cleaning prevents chips and liquids from entering the shaft during atool change and causing contamination and damage to the inner taper andthe clamping system.5.6 Pneumatic tool changeFor guidelines on air quality,see "Air purity classes (ISO8573-1) [} 24]" section.The tool change or tool taper change is performed pneumatically.During this, a mechanism is operated inside the HF spindle which clamps, re-leases, or ejects the tool taper or collet.