IKA A 11.6 double beater, stainless steel, for A 11.4 mixing beaker, 0003302900

Kinetics of impact comminution on a scaled-up macro-scale

In instrumental analysis, scaling the sample volume leads to a significant change in the physics of comminution. When the IKA A 11 basic analytical mill is operated with the large 250 ml grinding chamber (A 11.4), the axial reach of a standardised single beater is no longer sufficient to penetrate the increased volume kinetically. The IKA A 11.6 dual-beater has been geometrically engineered precisely for this macro-scale. Driven at up to 28,000 revolutions per minute, this tool simultaneously applies immense mechanical impulses across two superimposed planes of rotation. This dual impact energy shatters soft to medium-hard solids (up to approx. Mohs hardness 3) with enormous efficiency, as the probability of a direct particle impact on the striking edges is drastically increased by the doubled effective surface area.

Macro-fluid dynamics and vortex generation

A fundamental mechanical problem in comminution within large-volume chambers is the formation of fluid dynamic dead zones – areas in which the sample material accumulates without being caught up in the rotor’s kinetics. The asymmetrical blade geometry of the A 11.6 double-beater functions not only as an impact tool but also as a hydrodynamic impeller. The high-speed rotation generates massive three-dimensional flow turbulence (vortices). These vectorial flows force the entire particle matrix into continuous vertical and radial circulation, thereby constantly drawing the material back into the active impact zones and achieving a strictly homogeneous particle size distribution across the entire 250 ml batch.

Material integrity and thermomechanical stability

The acceleration of large sample volumes induces significant torsional forces on the drive shaft and the tool itself. To prevent plastic deformation under this continuous load, the double beater is made from solid, tough stainless steel. This monomaterial design guarantees the highest tribological resistance to mechanical abrasion and prevents analytical contamination of the sample (carry-over). The electropolished, seamless metal surface enables full compliance with GLP (Good Laboratory Practice) guidelines through complete chemical decontamination and residue-free thermal sterilisation in an autoclave.

Technical details

• Product type: Double-beater / Extended grinding tool
• Processing principle: Impact and percussion comminution on two levels
• Fluid mechanics: Three-dimensional vortex generation on a macroscopic scale
• Physical scope of application: Soft to medium-hard sample matrices (up to Mohs hardness 3)
• Compatibility (vessel): Essential for the IKA A 11.4 grinding beaker (250 ml)
• Compatibility (drive): Exclusively compatible with the IKA A 11 basic analytical mill
• Material: Solid, highly wear-resistant stainless steel
• Assembly: Form-fit, tool-free locking onto the drive shaft
• Hygiene: Fully thermally autoclavable

Contents

• 1 x IKA A 11.6 double beater (stainless steel)

(Important note: The A 11 basic drive unit and the essential A 11.4 grinding beaker are not included in the scope of delivery!)

Individual requirements & accessories

The A 11.6 double beater is not a self-contained standard tool, but forms an essential fluid-dynamic unit together with the IKA A 11.4 grinding beaker (item no. 0002904100). The use of this double beater in the small 80 ml standard beaker is geometrically impossible. Please also note that when grinding large volumes, the thermodynamic load (exothermic reaction due to frictional heat) on the drive motor increases; the maximum duty cycles (ED) defined by IKA must be strictly adhered to in order to protect the motor windings from overheating. Please contact our procurement service at any time for metrologically correct scaling of your grinding processes.