News
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Entrapped Air and Bubble Retention in Sealing Grooves
Executive Summary Entrapped air in a sealing groove is not a simple filling nuisance. It is a boundary-condition error created when groove geometry, seal compression, filling path, vent access and surface wetting do not allow gas to leave before the interface becomes closed. The retained gas may ...Read more -
Dynamic O-Ring Sealing: Frictional Heat, Wear Particles and Service-Life Control
Executive Summary Dynamic O-ring sealing is a tribological problem, not a static compression problem with motion added afterward. The seal must maintain contact pressure while sliding against a shaft, rod, piston or sleeve. Frictional work is produced at the dynamic contact band, converted into l...Read more -
Low-Temperature Rubber Sealing: Glass Transition, Recovery Loss and Cold-Start Leakage
Executive Summary Low-temperature rubber sealing fails through coupled changes rather than one temperature threshold. Cooling reduces segmental molecular mobility, raises modulus and slows compression recovery before a visible leak. Near a glass-transition region, the response can depend strongly...Read more -
EPDM Volume Change in Ethylene-Glycol Coolants: Swelling, Additive Compatibility and Seal Stability
Executive Summary: Volume Change Is a System Response An EPDM seal in ethylene-glycol coolant is exposed to a multicomponent fluid, not glycol alone. Water, glycol, inhibitors, buffers, anti-foam agents, stabilizers, contaminants and oxidation products affect uptake, extraction, lubrication and s...Read more -
Hydrolysis Risk of PU Seals in Water-Based Media: Swelling, Hardness Drift and Long-Term Leakage
Executive Summary: The Failure Chain Is Longer Than Water Exposure A PU seal in a water-based medium does not fail through one isolated event. Water absorption begins at the exposed surface, water diffusion develops a concentration gradient through the section, and the medium chemistry determines...Read more -
FFKM Surface Erosion in Plasma Environments: Particle Generation, Seal Integrity and Cleanliness Control
Executive Summary: Surface Damage Precedes Many Vacuum Failures FFKM surface erosion in a plasma chamber is not simply a question of whether the polymer survives a nominal temperature. The exposed surface receives a chemically specific combination of radicals, ions, ultraviolet radiation, heat an...Read more -
Rapid Gas Decompression Failure in Rubber Seals: Crack Initiation, Pressure Release and Material Selection
Executive Summary: Why Immediate Leak-Free Results Are Not Enough Rapid gas decompression (RGD) failure occurs when an elastomeric seal exposed to high-pressure gas is depressurized faster than gas can leave its internal structure. External pressure falls first while sorbed gas remains and expand...Read more -
PTFE Creep and Bolt Preload Loss: Long-Term Compression Stability in Bolted Sealing Joints
Executive Summary: Why Initial Sealing Does Not Guarantee Long-Term Sealing A PTFE bolted joint can pass an initial pressure-hold test and later leak without visible nut rotation. The test proves containment only at its defined pressure, temperature, assembly condition and duration; it does not p...Read more -
Double Mechanical Seals for Chemical Pumps: Barrier Fluid, Heat Accumulation and Hazardous-Media Isolation
Executive Summary Double mechanical seals for chemical pumps form a controlled leakage and hazardous-media isolation system, not a zero-leakage guarantee. The inboard seal faces the process fluid; the outboard seal faces the atmosphere or a support-fluid cavity. A barrier or buffer fluid, reservo...Read more -
LNG Cryogenic Valve Sealing: Thermal Contraction, Stem Movement and Low-Temperature Leakage
Executive Summary LNG cryogenic valve sealing is a coupled thermal, mechanical and fluid-boundary problem. Valve body, bonnet, stem extension, seats, stem packing, glands, body-bonnet gaskets and end connections each protect a different leakage path. Reliability depends on thermal-contraction com...Read more -
Electrolyzer End-Plate Sealing: Alkaline Solution, Pure Water and Stack Compression Stability
Executive Summary Alkaline electrolyzer end-plate sealing is a system-level boundary problem. End-plate geometry, gasket compression, stack alignment, compression uniformity, chemical compatibility and cycling history determine whether alkaline solution, pure water and gas-side spaces remain sepa...Read more -
High-Pressure Hydrogen Storage Valve Sealing: Hydrogen Permeation, Depressurization Cycling and Elastomer Failure
Executive Summary High-pressure hydrogen valve sealing is a coupled materials, geometry and pressure-history problem. Valve architecture, elastomer formulation, seal geometry, extrusion-gap control, compression, pressure cycling, temperature, surface condition, assembly quality and leak verificat...Read more