Need to use magnetic fluid seals but not sure which type to choose?
The following will provide detailed instructions for such users:
Why are magnetic fluid seals needed in vacuum environments?
How to select a magnetic seal for vacuum applications?
How durable are magnetic fluid seals in a vacuum environment?
Please select the magnetic seal product that meets your usage needs.
Magnetic seals are mainly used in vacuum environments. The following article will describe what a vacuum environment is and the role magnetic fluid seals play in it.
A vacuum is a state in which there are very few gas molecules in space. Although it is difficult to achieve an “absolute vacuum” in which there are no molecules at all, we usually refer to a state in which the air pressure is lower than atmospheric pressure as a vacuum.
Depending on the requirements of the application, it is necessary to create different levels of vacuum, which is called “vacuum degree”.
Vacuum environments are used in a wide variety of fields. For example, vacuum packaging to prevent oxidization of foodstuffs, the manufacturing process of electronic components, and the exploration of the universe all require the use of a vacuum. Vacuum also plays an important role in hot water bottles, which retain heat well, and in distillation equipment, which utilizes the principle of substance evaporation, and plays a key role in our daily lives.
In order to maintain a vacuum environment, it is necessary to completely seal the gap between the rotating shaft and the fixed part. However, if this gap is simply sealed, contact between the rotating shaft and the stationary part occurs, resulting in friction, wear, and particle shedding.
Magnetic sealing is an innovative technology that solves this problem. It is a non-contact sealing structure that utilizes a special liquid called “magnetic liquid,” which is held between the rotating shaft and the stationary part under the action of a magnetic field.
Since the magnetic fluid is in a liquid state, there is no friction or wear, and dust is minimized. Also, by adjusting the strength of the magnetic force, it is possible to adapt to various pressure differences, providing excellent performance even in high vacuum environments.
In summary, magnetic sealing is an ideal solution for rotary shaft sealing in vacuum environments, and is a key technology indispensable for realizing high-precision and high-reliability vacuum environments.
When selecting a magnetic seal for a vacuum device, factors such as loading conditions, target vacuum and ultimate pressure, speed and torque, and temperature environment need to be considered. Selecting the appropriate magnetic seal for each requirement maximizes the performance of the device and ensures its stable operation.
When selecting a magnetic seal, its ability to withstand loads is an extremely important evaluation index. At the design stage, it is necessary to reasonably calculate the service life of the bearing based on the expected external forces such as radial load, axial load and rotational torque, and to select a magnetic seal product that matches it.
As the load increases, the dynamic life of the bearing decreases. In particular, the rotating moment will produce a bias load or excessive force on the bearing, which has a particularly significant impact on its life, and is a factor that must be emphasized in the design.
Therefore, in the process of magnetic seal selection, it is necessary to accurately grasp the relationship between load factors and bearing life, and select products that meet the required load-bearing performance, which is the key to realizing the overall reliability and long-term stable operation of the system.
In the selection of magnetic fluid seals, the required vacuum level and its corresponding pressure value are also key factors. According to the actual required vacuum and pressure, the matching magnetic seal model needs to be selected.
Magnetic fluid seals are usually labeled with the ultimate vacuum and pressure range they can withstand. By referring to these data, you can select the product that is best suited to the intended use.
Generally speaking, the higher the vacuum level, the lower the internal pressure, and at the same time the pumping speed will be slowed down; while at lower vacuum levels, the pressure is higher and the pumping speed is relatively faster. Therefore, when selecting a magnetic seal, it is important to understand the relationship between these parameters to ensure that the selected product can respond to the actual vacuum performance required.
When magnetic fluid seals are used in a vacuum environment, their ability to cope with speed and torque is also critical. Since magnetic fluid seals are mainly used to seal shafts that rotate at high speeds, they must have a certain degree of high-speed durability. At the same time, they also need to have the ability to withstand the torque transmitted on the shaft.
Different models of magnetic fluid seal vary significantly in terms of maximum speed, rated speed, tolerable transmission torque, and starting torque. These parameters are influenced by factors such as the type of magnetic fluid, bearing loading conditions, etc.
Therefore, when selecting a model, it is necessary to refer to these values, combined with the speed and torque conditions in the actual use of the environment, to make a reasonable judgment.
For example, in application scenarios that require high-speed rotation, a magnetic seal with a higher maximum speed should be selected; in transmission applications with large loads, a model with strong torque transmitting capability should be selected. In addition, the starting torque represents the maximum resistance to be overcome during startup, and it is recommended that three times the starting torque be used as the design reference value when selecting a motor.
It can be seen that a reasonable response to the speed and torque requirements is an important link that cannot be ignored in the selection process of magnetic fluid seals.
Magnetic fluid seals must also adapt to temperature changes in the operating environment. Temperature changes will affect the viscosity and magnetic properties of the magnetic fluid, which may lead to a decline in sealing performance.
When selecting a model, it is important to check the operating temperature range of the magnetic seal. Typically, an increase in temperature results in a decrease in the viscosity of the magnetic fluid; a decrease in temperature results in an increase in viscosity. At extreme high or low temperatures, the magnetic fluid may evaporate or freeze, rendering the seal ineffective.
When used in high-temperature environments, evaporation can be prevented by adding cooling structures or by using highly heat-resistant magnetic fluids; when used in low-temperature environments, freezing can be prevented by heating with a heater or by using magnetic fluids with excellent low-temperature performance.
In order to select the most suitable magnetic seal, the manufacturer should be consulted in detail and fully informed of the specific temperature conditions.
Through comprehensive consideration of the above factors and reasonable selection, you can ensure that the magnetic seal realizes the best performance in the vacuum device and ensures the stable and reliable operation of the equipment.
With proper selection and maintenance, magnetic fluid seals can continue to perform consistently over long periods of time. Factors affecting the durability of magnetic fluid seals include deterioration of the magnetic fluid, material selection, and the environment in which they are used.
Deterioration of magnetic fluid
Magnetic fluids may deteriorate due to factors such as high temperatures or corrosive gases. In general, the life of a magnetic fluid varies greatly depending on the conditions of use. For example, magnetic fluids tend to deteriorate faster in high-temperature environments.
Material selection
The materials used for magnetic fluid seals can have a significant impact on their durability. For example, when used in environments where corrosive gases are present, it is important to select materials with corrosion resistance. If the material is not selected properly, the seal assembly may be damaged.
Influence of the operating environment
The operating environment itself also affects the durability of magnetic fluid seals. For example, rotational vibration can shorten the service life of bearings, and the performance of magnetic fluid seals can be degraded in environments where there is interference from external magnetic fields.
Importance of regular maintenance
Regular maintenance is essential to maintain the durability of magnetic fluid seals. Maintenance includes replacing the magnetic fluid, inspecting the sealing material, and so on. By performing regular maintenance, you can effectively extend the service life of the magnetic seal and ensure its continuous and stable performance.
Reliable magnetic fluid seals from leading ferrofluid suppliers are essential in the development and manufacture of equipment and machinery that require high vacuum environments. Moretec Corporation is a company that provides magnetic fluid seals, magnetic fluid seals, vacuum seals, and other products, covering a complete system from development to manufacturing and sales. We provide the most suitable magnetic seals according to the needs of our customers.
Moretec Corporation is able to design customized magnetic fluid seals to meet customer needs. We also provide detailed information on the specifications and performance of each product to ensure that our customers can entrust us with confidence.
Magnetic fluid seals play an important role in maintaining a high vacuum environment. Moretec's many years of experience and track record of providing high-quality magnetic fluid seals help to improve the reliability of our customers' equipment and machinery.
Moretec Corporation is committed to earning the trust of our customers through our strong technical capabilities, quality control capabilities, and stable supply. If you are looking for magnetic fluid seals suitable for vacuum environments, please feel free to inquire with Moretec Corporation.
