In the connection of industrial pipelines, valves, and pressure vessels, sealing is a crucial element for ensuring safety, preventing leaks, and improving efficiency. Faced with harsh media, extreme temperatures, and pressures, selecting a high-performance gasket is essential. Among numerous sealing materials, PTFE flange gaskets stand out due to their unique comprehensive performance, earning them the reputation of being an outstanding representative of the “King of Plastics” in the sealing field. They have not only solved numerous industrial problems but have also become an indispensable sealing element in high-standard industries such as chemical, pharmaceutical, and food processing.
1.The advantages of PTFE flange gaskets
Unparalleled Corrosion Resistance：This is the most remarkable advantage of PTFE gaskets. Polytetrafluoroethylene (PTFE) possesses extremely high chemical stability, resisting corrosion from almost all chemical media, including strong acids (such as concentrated sulfuric acid and hydrochloric acid), strong alkalis, aqua regia, and various organic solvents. This makes it the preferred choice for piping systems handling highly corrosive fluids, effectively preventing leaks and safety accidents caused by gasket corrosion.
Wide Temperature Range：PTFE flange gaskets maintain their excellent mechanical properties and sealing performance over a wide temperature range of -200°C to +260°C. Whether in cryogenic environments like liquid nitrogen and liquid oxygen, or high-temperature steam, it handles them with ease, ensuring reliable sealing even under drastic temperature changes.
Excellent Anti-sticking Properties and Extremely Low Coefficient of Friction：PTFE has one of the lowest coefficients of friction among all solid materials, while also exhibiting excellent anti-sticking properties. This means that media are difficult to adhere to the gasket surface and will not stick to the product, making cleaning and maintenance very easy. This characteristic is particularly important in industries with extremely high cleanliness requirements, such as food and pharmaceuticals, effectively preventing material contamination and cross-contamination.
Excellent Sealing Performance and Flexibility：PTFE materials possess a certain degree of flexibility and compression resilience. Under the pre-tightening force of flange bolts, they can effectively fill the microscopic unevenness of the flange surface, forming a tight seal. Their extremely low permeability also effectively prevents molecular-level leakage, ensuring the long-term effectiveness of the seal.
Long Service Life and High Cost-Effectiveness：Due to their superior corrosion resistance and aging resistance, PTFE flange gaskets are not prone to aging, embrittlement, or deformation under normal operating conditions, resulting in a service life far exceeding that of ordinary rubber or asbestos gaskets. Although their initial purchase cost may be higher than some traditional materials, considering the maintenance costs, downtime losses, and safety throughout the entire equipment lifecycle, their overall cost-effectiveness is very high.
2.Precautions when using PTFE flange gaskets
Pay attention to cold flow properties and clamping force.
Pay attention to the upper limit of operating temperature.
Select the appropriate gasket type.
Ensure the flange surface is clean and flat.
3.Conclusion
PTFE flange gaskets, with their comprehensive and outstanding corrosion resistance, high and low temperature resistance, anti-sticking properties, and sealing performance, have become a powerful tool for solving complex sealing problems in modern industry. Like a loyal and reliable guardian, they silently protect the safety of pipeline connections. However, users also need to fully understand their material properties, especially cold flow characteristics, and only through correct selection, standardized installation, and meticulous maintenance can the potential of this “sealing guardian” be maximized, thus providing the most solid guarantee for the long-term, safe, and stable operation of equipment.
