High-speed refrigerated centrifuge high-speed rotating seal design

　　 High-speed refrigerated centrifuge The high-speed rotating seal is a mechanical sealing structure, also known as a face seal, primarily used for sealing rotating shafts. During high-speed rotation, the main spindle drives the rotating seal’s moving ring to rotate at the same speed via an anti-rotation pin. Meanwhile, the stationary seal ring remains stationary during operation, thus creating a rotating friction surface between the stationary and moving rings—this friction surface is the critical sealing interface. The sealing chamber is evacuated under vacuum and operates without coolant flushing, making it a dry-friction structure designed specifically to achieve vacuum sealing. In high-speed refrigerated centrifuges, static seals using O-rings can be employed elsewhere within the working chamber. However, when it comes to transmitting rotational motion from the main spindle to the working rotor, traditional sealing elements can no longer meet the required performance standards. Therefore, it is essential to design a specialized sealing structure that can satisfy these demands.
　　Every biochemistry and molecular biology laboratory, as well as various universities, should be equipped with high-speed refrigerated centrifuges of multiple models. Centrifugation technology is primarily used for the separation and preparation of diverse biological samples. Under high-speed rotation, the suspension of biological samples experiences tremendous centrifugal forces, causing tiny suspended particles (such as organelles and precipitates of biomacromolecules) to settle at a certain rate, thereby separating them from the solution. The settling velocity depends on the mass, size, and density of the particles. The application of centrifuges in the field of biological sciences is already extensive, and the centrifugation technology employed by high-speed refrigerated centrifuges has long played a crucial role in biological sciences—particularly in biochemical and molecular biology research. Today, we’ll focus on introducing... High-speed refrigerated centrifuge What role does it play in the field of biological sciences? I hope it can be helpful to everyone.
　　In general, low-speed centrifugation is typically described in terms of rotational speed measured in "rpm," whereas the centrifugal force generated during high-speed refrigerated centrifugation is expressed in "g." It should be noted that since the distance "r" between the centrifuge tube and the center of the rotation axis varies—resulting in different positions of sedimenting particles within the centrifuge tube—the centrifugal force experienced by these particles also differs accordingly. Therefore, when reporting ultracentrifugation conditions, it is customary to use the multiple of Earth's gravitational acceleration, "×g," rather than the number of revolutions per minute (rpm), as this accurately reflects the centrifugal force acting on particles at various positions within the centrifuge tube and their dynamic changes over time. In scientific literature, data on centrifugal force usually refer to the average value (RCFav)—that is, the centrifugal force at the midpoint of the centrifuge tube.
　　To facilitate the conversion between rotational speed and relative centrifugal force, Dole and Cotzias developed a nomogram that illustrates the relationship among rotational speed (in rpm), relative centrifugal force (RCF), and radius of rotation (r). This graphical method is more convenient than using formulas for calculation. When converting between these parameters on a high-speed refrigerated centrifuge, first locate the known radius on the r scale and the known centrifuge speed on the rpm scale. Then, draw a straight line connecting these two points; the intersection of this line with the RCF scale on the diagram will give you the corresponding value of the relative centrifugal force. Note that if the known speed value falls to the right of the rpm scale, you should read the value from the right side of the RCF scale; if the speed value falls to the left of the rpm scale, you should read the value from the left side of the RCF scale.
　　 High-speed refrigerated centrifuge It is one of the most commonly used basic pieces of equipment in laboratories and is widely applied in hospital labs. Centrifuges are indispensable tools for tasks such as separating serum from blood, precipitating formed cells, concentrating bacteria, and performing PCR tests, among others. When selecting a centrifuge, you should primarily consider two factors—rotational speed and capacity—based on the volume of work you need to handle.