High-pressure and High-temperature Sealing Ring Comprehensive Analysis
I. Definition and Core Characteristics
High-pressure and high-temperature seals are elastic sealing elements primarily made of fluoroelastomer (FKM), designed for high-pressure (≤800MPa), high-temperature (≤250℃) and strongly corrosive environments. They are widely used in the petrochemical industry, energy equipment, and aerospace fields. Their core features include:
Withstanding extreme conditions: Can operate stably for long periods at high temperatures of 200℃ to 250℃, and withstand short-term exposure up to 300℃; maintains seal integrity under high-pressure environments (such as 800MPa).
Chemical Inertness: Excellent resistance to media such as fuel, hydraulic oil, strong acids (nitric acid, sulfuric acid), and strong oxidizers (hydrogen peroxide), with swelling rate <5%.
II. Material and Structural Design
Performance Advantages of Fluororubber (FKM):
Molecular structure characteristics: The main chain contains fluorine atoms, which enhance the stability of C-C bonds through strong adsorption effects, significantly improving resistance to chemical corrosion and oxidation.
Mechanical Properties: Tensile strength gradually decreases with temperature rising below 150℃, the performance attenuation slows down in the range of 150℃ to 260℃, and the hardness change is controllable at high temperatures.
Ozone Resistance: Retains performance with no significant decline after 10 years of storage in natural conditions, superior to conventional rubber.
Enhanced Design
Composite copolymer structure: Enhances high-temperature sealing stability.
Frame support: Utilizes PTFE or metal frame insertion for enhanced extrusion resistance, suitable for dynamic high-pressure sealing applications (e.g., hydraulic cylinders).
III. Application Scenarios
Petroleum & Chemical Industry: High-pressure reactors, LNG tank flange seals, withstanding acidic mediums and 250℃ high temperatures.
Energy Equipment: Gas turbines, high-temperature steam pipeline interface seals, pressure-bearing up to 800MPa.
Aerospace: Rocket fueling system sealing to prevent leaks
Industrial Hydraulics: High-pressure pump valves, hydraulic cylinder seals, compatible with mineral oils and synthetic ester-based fluids.
