Rotors

Standard and High-Pressure Rotors

Milestone's patented Microwave Digestion Rotor (MDR) technology provides unsurpassed performance capabilities and the highest standard of safety in closed-vessel microwave digestion.

MDR rotors hold multiple microwave digestion vessels in a high strength rotor body. This unique design securely retains sample vessels during microwave digestion and vessel uncapping for maximum user safety. The digestion vessels used have no molded or machined threads than can be weakened by acid vapors during vessel venting and opening.

Milestone has always used the highest quality Teflon materials for our microwave vessels and vessel covers. TFM (a thermally resistant form of Teflon) is chemically resistant at high temperatures to prevent melting & cracking. No reforming tool or molding station is required to reshape covers. Vessels are isostatically pressed, not molded, to minimize contamination during manufacturing. The result is longer lifetime and lower daily running costs. Compare a Milestone microwave vessel to any other current design and you will see that the vessel quality and substance are superior.

All digestion vessels in MDR rotors are protected by a patented reclosing (vent and reseal) relief valve mechanism. Vessels are fitted into a MDR rotor body and are sealed using a calibrated torque wrench, which ensures that each vessel is sealed for maximum operating pressure and will safely vent when a build-up of gases (CO₂ and NO_x) is in excess of the vessel's maximum operating pressure. (You can read more about Milestone's vessels.)

Two different styles of rotors are available: high-pressure and medium-pressure. The Medium Pressure digestion rotor is a general purpose carousel suitable for most samples. The high-strength rotor body holds twelve digestion vessels made of high-purity TFM. Allows for the complete digestion of water, sludge, municipal waste, biological materials, metals, and alloys.

The High Pressure digestion rotor is a strong ten-position rotor suitable for all sample types, including difficult organic and inorganic refractory metals. It ensures complete digestion of larger amounts of highly reactive organics, such as food/feed, oils, plastics, and pharmaceuticals.

Medium Pressure Rotor	High Pressure Rotor

Segmented rotors allow each vessel segment to be individually inserted and removed. Each vessel segment is sequentially numbered for position indexing/automation.

A unique cooling apparatus can be used with segmented rotors to increase air flow during the digestion or when the run is complete. This can be used for any sample, but is particularly recommended for high-temperature digestions or with our unique high-temperature rotor.

Unlike other sample carousels in the market, both Milestone rotor styles can also be cooled in a water bath for quick turn-around in high-throughput environments.

Immersing vessels in a water or ice bath cuts cooling time in half. Unlike the Kevlar shields used in other technologies, all of Milestone's vessel materials are water friendly, so a fully loaded sample rotor can be cooled in about 10 minutes. Rapid cooling also extends the lifetime of sample rotors and vessel components.

Rotor Specifications

	High-Pressure Rotor (SK-10)	Medium Pressure Rotor (SK-12)
Style	Segmented	Segmented
# of Samples	10	12
Vessel Volume	100 mL	100 mL
Maximum Operating Pressure	100 Bar (1500 psig)	35 Bar (500 psig)
Maximum Operating Temperature	300 °C	300 °C
Water Cooling	Yes	Yes
Typical Applications	Complete digestion of organic samples with fast reacting exothermic solids and liquids, inorganic samples, larger environmental samples, metals and alloys.	Complete digestion of water, sludge, municipal waste water, biologicals, acid leaching of soils and sediments, environmental samples, metals and alloys

Microsampling Inserts

3-position Teflon (6 mL) or Quartz (3 mL) inserts for microsampling applications Process up to 36 samples per run in a 12-position rotor Reach up to 240 °C and 30 bar within sealed vessel Ideal for small sample processing Fits within standard 100 mL vessels; uses standard temperature monitoring

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TFM-35 Teflon Inserts

35 mL Teflon insert Ideal for smaller samples Minimize acid volume Optimize dilution factor Fits within standard 100 mL vessels; uses standard temperature monitoring

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QS-50 Quartz Inserts

50 mL high-purity quartz inserts Complete recovery of volatile elements Convex cover retains condensed analytes in the vessel Minimize electrostatic effects Fits within standard 100 mL vessels; uses standard temperature monitoring

Continue to High-Throughput Rotors —>

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