What are the isolation membrane materials for pressure water tanks?

In ships and similar water treatment systems, pressure tanks are key components whose performance and stability directly affect the efficiency and safety of the entire water supply system. As one of the core components inside the pressure water tank, the isolation membrane not only needs to withstand changes in water pressure, but also needs to have good sealing, corrosion resistance, and durability.

1. Polyethylene

Polyethylene is a widely used thermoplastic with excellent chemical corrosion resistance, good flexibility, and processability. In pressure water tanks, low-density polyethylene and high-density polyethylene are often used as isolation film materials because they can effectively isolate water from compressed air while maintaining good mechanical strength and aging resistance.

2. Polyvinyl chloride

Polyvinyl chloride is a plastic material that is inexpensive, easy to process, and resistant to chemical corrosion. In the pressure water tank, PVC isolation film can resist the erosion of various chemicals, including chloride ions in water. However, PVC is prone to decompose and produce harmful substances at high temperatures, so its usage temperature needs to be controlled within a certain range.

3. Rubber materials

Rubber materials are widely used in pressure water tank isolation membranes due to their excellent elasticity and sealing properties. Common rubber materials include natural rubber, butyl rubber, chloroprene rubber, etc. These materials can effectively prevent the infiltration of water and air, while also possessing a certain degree of corrosion resistance. However, it should be noted that the tolerance of different rubber materials to specific chemicals varies, and the selection should be based on the specific usage environment.

4. Fluoroplastics

Fluoroplastics, especially polytetrafluoroethylene, are known for their excellent corrosion resistance, high temperature resistance, and low friction coefficient. In pressure water tanks, PTFE isolation membranes can resist almost all chemical substances, including strong acids, strong bases, and organic solvents. In addition, its good self-lubricating properties also help reduce friction and wear, extending its service life.

5. Nylon

Nylon is a high-strength and wear-resistant synthetic fiber material, often used as an isolation membrane for pressure water tanks. Nylon isolation film not only has excellent mechanical properties, but also has a certain degree of corrosion resistance, which can resist the erosion of various chemical substances. Meanwhile, nylon material is easy to process and can be customized according to specific needs.

6. Polyester

Polyester materials, especially polyethylene terephthalate, are favored for their excellent transparency, chemical resistance, and mechanical strength. In pressure water tanks, although PET isolation membranes are not as corrosion-resistant as PTFE, they can still exhibit good performance in general water treatment environments. In addition, PET material also has good processability and recyclability.

7. Other polymer materials

In addition to the common materials mentioned above, many other polymer materials are also used in the manufacturing of isolation membranes for pressure water tanks. These materials may have unique performance characteristics, such as higher heat resistance, better weather resistance, or lower cost. The specific choice of material for the isolation membrane needs to be comprehensively considered based on factors such as the usage environment, performance requirements, and economy of the pressure water tank.