What are the common types of sealing strip designs for chest freezers

As a kind of equipment mainly used for long-term frozen storage of food, the sealing performance of the chest freezer is directly related to the preservation effect, energy efficiency level and user experience of the product. Among the many design details, the structure and material selection of the gasket play a vital role. As the sealing interface between the door and the cabinet, the design quality of the gasket will affect the key performance indicators such as the maintenance of cold air, the energy consumption performance of the freezer and the defrosting cycle.
The gasket of the chest freezer is usually installed on the contact surface of the lower edge of the door. Its main function is to form a continuous sealing boundary to prevent the cold air in the cabinet from escaping, and to prevent the external moisture and hot air from entering the cabinet, so as to maintain the stability of the internal low temperature environment. According to different application requirements and manufacturing cost considerations, the structural design and material composition of the gasket show a diversified trend.

Common types of chest freezer gaskets mainly include the following:
Single-chamber magnetic gasket
This is the most common gasket structure. It has a magnetic rubber strip embedded inside and a flexible PVC material wrapped outside. The door is adsorbed on the freezer cabinet by magnetic force to form a seal. This type has a simple structure, low cost, easy manufacturing and replacement, and is suitable for small and medium-capacity household freezers.
The sealing performance of the magnetic sealing strip is closely related to its magnetic strength, elastic structure and installation position. When designing, it is necessary to ensure that the sealing strip will not be twisted or fall off during normal opening and closing, and at the same time have a certain flexibility to adapt to the slight deformation between the door frame and the box body. In addition, the magnetic force must be evenly distributed to ensure that there are no air leaks on the edges.
Double-chamber magnetic sealing strip
This design adds a second sealing cavity on the basis of the single-chamber structure. It is usually a structure with two airbag cavities arranged in parallel, and the double-layer structure forms a better insulation and leakproof effect. This type is more common in high-end household or commercial freezers.
Double-chamber magnetic sealing strips can effectively reduce the cold bridge effect and enhance the sealing redundancy, especially in the use environment with large temperature differences. In the energy efficiency rating assessment, equipment using double-chamber sealing strips usually get higher scores because it reduces the cold air loss rate and reduces the compressor load.
Non-magnetic airbag sealing strip
This structure mainly relies on the elasticity and structural deformation of the flexible material itself to complete the sealing, without using magnetic materials. Its advantage is that it can avoid the long-term performance degradation problem caused by the demagnetization of the magnetic strip, and it has certain advantages in some industrial or special environments with high non-magnetic requirements.
Non-magnetic sealing strips are generally made of multi-layer co-extruded PVC or thermoplastic elastomer (TPE), and the structure contains a closed airbag, which is compressed to form a seal when the cabinet door is closed. This type requires high matching accuracy between the door frame and the cabinet body, and the elastic rebound performance and low temperature aging resistance must be considered during design.
Embedded double-layer sealing strip
This type of sealing strip design embeds part of the structure into the cabinet door and combines it with the external decorative cover or liner board to form a more integrated appearance and structure. Commonly used in commercial freezers and high-end brand products.
The embedded design not only improves the sealing performance, but also reduces the risk of contamination of the exposed part of the sealing strip, and improves the aesthetics and cleaning convenience of the whole machine. Due to the complex structure, its production and assembly costs are relatively high, but it can extend the service life of the sealing strip and reduce the maintenance frequency.