| HS Code | Official Doc | Tariff Rate | Origin | Destination | Effective Date |
|---|---|---|---|---|---|
| 8421110000 | Doc | 55.0% | CN | US | 2025-05-12 |
| 8421190000 | Doc | 56.3% | CN | US | 2025-05-12 |
| 8479899565 | Doc | 32.5% | CN | US | 2025-05-12 |
| 8479899595 | Doc | 32.5% | CN | US | 2025-05-12 |
| 9024800000 | Doc | 55.0% | CN | US | 2025-05-12 |
| 9031808085 | Doc | 30.0% | CN | US | 2025-05-12 |
| 9031804000 | Doc | 55.0% | CN | US | 2025-05-12 |
Centrifuge Machine
A centrifuge is a laboratory device used for separating substances of different densities, enabled by the principle of sedimentation. The process exploits centrifugal force to accelerate the settling of particles or liquids.
Material
Centrifuges are constructed from a variety of materials, dependent on their application and the forces they generate. Common materials include:
- Stainless Steel: Predominantly used for rotors and the main body due to its corrosion resistance and strength.
- Aluminum Alloys: Employed in rotors where lighter weight is required, but with reduced strength compared to stainless steel.
- Titanium Alloys: Used in high-speed rotors due to their exceptional strength-to-weight ratio and resistance to corrosion, despite higher cost.
- Polymers (e.g., Polypropylene, Polycarbonate): Used for tubes and containers, particularly for lower-speed applications or disposable applications.
- Composite Materials: Increasingly used in rotors to achieve optimal strength and weight characteristics.
Purpose
The primary purpose of a centrifuge is separation. Specific applications include:
- Biological Research: Separating cellular components (e.g., nuclei, mitochondria, proteins), isolating DNA/RNA, purifying viruses.
- Medical Diagnostics: Separating blood components (e.g., plasma, red blood cells, white blood cells), urine analysis, isolating pathogens.
- Chemical Engineering: Separating precipitates from solutions, clarifying liquids, particle size analysis.
- Food Industry: Separating cream from milk, clarifying juices, recovering solids from liquids.
- Environmental Science: Separating solids from water samples, analyzing sediment composition.
Function
Centrifuges function by rotating samples at high speeds. This generates centrifugal force, which causes denser substances to move outwards from the axis of rotation, while less dense substances remain closer to the axis. Key functional aspects include:
- Rotor: Holds the sample tubes and rotates at high speed. Different rotor types are available for different tube sizes and applications.
- Motor: Provides the rotational force. Motor speed is a critical parameter, often expressed in revolutions per minute (RPM) or relative centrifugal force (RCF, measured in g).
- Control System: Allows precise control of speed, time, and temperature.
- Chamber: Encloses the rotor and provides a sealed environment. Temperature control is often incorporated to maintain sample integrity.
- Braking System: Safely decelerates the rotor at the end of the run.
Usage Scenarios
Centrifuges are used in a wide range of laboratory and industrial settings:
- Benchtop Centrifuges: Commonly found in research laboratories for routine separations.
- Floor-Standing Centrifuges: Used for larger sample volumes and higher speeds.
- High-Speed Centrifuges: Employed for separating very small particles, such as viruses and proteins.
- Ultracentrifuges: Used for extremely high speeds and separating even smaller particles, such as ribosomes and macromolecules.
- Clinical Centrifuges: Specifically designed for medical diagnostic applications.
- Preparative Centrifuges: Used for large-scale separations in industrial processes.
Common Types
- Fixed-Angle Centrifuges: Rotors have tubes held at a fixed angle. Good for pelleting samples.
- Swinging-Bucket Centrifuges: Rotors have tubes that swing outwards during rotation, forming a horizontal plane. Provides better separation for density gradient centrifugation.
- Microcentrifuges: Small centrifuges for low-volume samples (typically 0.2-2.0 mL).
- Hematocrit Centrifuges: Specifically designed for determining the hematocrit (percentage of red blood cells in blood).
- Gas Centrifuges: Used for isotope separation, notably in uranium enrichment.
- Density Gradient Centrifuges: Utilizes gradients of density to separate particles based on size and density.
Centrifuge machines fall under several classifications depending on their specific function and application. Here's a breakdown of relevant HS codes based on the provided information:
- 8421.11.00.00: This HS code covers Centrifuges, including centrifugal dryers; filtering or purifying machinery and apparatus, for liquids or gases; parts thereof: Centrifuges, including centrifugal dryers: Cream separators. This is specifically for cream separators, a type of centrifuge. The tax rate details are: Basic tariff: 0.0%, Additional tariff: 25.0%, Post-April 2, 2025, additional tariff: 30.0%, with a total tariff of 55.0%.
- 8421.19.00.00: This HS code covers Centrifuges, including centrifugal dryers; filtering or purifying machinery and apparatus, for liquids or gases; parts thereof: Centrifuges, including centrifugal dryers: Other. This classification is for centrifuges (including centrifugal dryers) that are not cream separators. The tax rate details are: Basic tariff: 1.3%, Additional tariff: 25.0%, Post-April 2, 2025, additional tariff: 30.0%, with a total tariff of 56.3%.
It is important to determine the specific function of the centrifuge machine to select the correct HS code. If the centrifuge is used for cream separation, 8421.11.00.00 is appropriate. For all other centrifuge applications, 8421.19.00.00 should be used.