VIBRATORY DISC MILL RS 200

VIBRATORY DISC MILL RS 200

This month we exported grinding jars that can match the German brand Retsch model RS200 to Serbia,

No grinder can beat the speed of a Vibratory Disc Mill when it comes to preparing samples for spectral analyses. RETSCH’s Vibratory Disc Mill RS 200 is ideally suited for fast and reproducible pulverization of hard, brittle and fibrous sample materials to analytical fineness.

The RS 200 runs steadily and smoothly, even with heavy grinding sets and at maximum speed thanks to its powerful Stabilized-Plane-Drive. It achieves grind sizes between 20 and 100 microns within seconds and with excellent reproducibility.

Grinding sets are available in a variety of sizes and materials. A set of sensors will recognize jars of tungsten or agate and automatically sets the maximum permissible speed, ensuring optimum results while protecting the material.

FAST & REPRODUCIBLE

• Very short grinding times, typically in the range of 60 to 180 seconds to achieve a fineness around 100 μm
• Ergonomic design and carry handles ensure easy handling of the grinding set
• Quick-action clamping system enables convenient and safe tightening of the grinding set
• Automatic speed reduction for agate and tungsten carbide sets
• Powerful Stabilized-Plane-Drive improves reproducibility
• Variable speed from 700 to 1500 rpm

PERFORMANCE TEST: SIZE REDUCTION AND REPRODUCIBILITY

The grinding results of a vibratory disc mill are significantly influenced by the movement patterns of the free masses inside the grinding jar. The new, powerful Stabilized-Plane-Drive of the RS 200 allows for extremely rapid formation of the movement pattern which is reflected in higher fineness and ultimately leads to significantly better reproducibility.

Figure 1 shows the standard deviation after 60 sec grinding time. It only takes a few large particles to impair the reproducibility of XRF measurements. Because of that, a small standard deviation for the d90 value is crucial.

Fig. 2: A “Quarter Minute Test” (QMT) evaluates the formation and stability of the movement patterns of Vibratory Disc Mills. Figure 2 shows that with the RS 200 a d90 value of 106 μm was obtained after a grinding time of only 15 seconds. The mills from three other manufacturers showed considerably inferior results.

• Grinding parameters
• Grinding jar: 100 ml
• Sample: cement clinker 0.85 to 3.15 mm
• Speed: Maximum (1200 rpm)
• Grinding time: 60 sec (Figure 1), 15 sec (Figure 2)

The grinding parameters are entered using a single button. The user can store up to 10 parameter combinations and choose between 13 languages for menu guidance. In addition to the current settings a colored graphics display shows service and operating information.

The grinding sets have been developed especially for extreme test conditions such as high sample throughput and high mechanical stress. Features include.

• safe, non-slip attachment with integral safety devices on cover and base
• gap between dish and cover edge for easy opening
• optimum sealing with O-ring
• protective jacket made from stainless steel (for agate, zirconium oxide and tungsten carbide dishes)
• grinding set identification (article number, material and volume)
• marking field (e. g. for information about sample)
• available in 3 sizes and 5 materials