7 common failures of metal-wound gaskets!

Metal spiral wound gaskets are the most widely used general-purpose seals in chemical engineering, piping, valves, heat exchangers, and pressure. Due to their moderate price, high-temperature and high-pressure resistance, and strong adaptability, they are used in almost all flange sealing applications. However, field technicians often encounter very frustrating problem: newly replaced spiral wound gaskets leak after a short period of use, fail to maintain pressure during testing, or even get blown out and damaged. Many people' first reaction is "poor gasket quality," but in real working conditions, 90% of spiral wound gasket failures are not caused by material issues, but by incorrect selection, improper, mismatched flanges, or improper loading. Today, I have summarized the 7 most common problems and highest rework rates found at construction sites. 

I. Problem 1:age upon new installation, pressure drop during testing (Most frequent) Field phenomenon: The gasket is newly replaced, but leaks slightly during pressure testing, fails to hold pressure steadily, visible damage is seen, and it continues to leak even after multiple disassembly and reassembly. Core reasons - Flange faces are not clean, containing rust, welding slag, or particulate, leading to poor gasket contact and micro-gaps. - Uneven bolt tightening, with one side tight and the other loose, causing the sealing surface to experience offset loading - Gasket is placed off-center, misaligned, or tilted, failing to be installed centrally. - Non-standard flanges or old flanges are deformed, resulting in uneven plane. Solutions - The flange sealing surface must be thoroughly cleaned before installation to ensure it is free of slag, rust, and uneven particles. - Strictly adopt the diagonal tightening method, tightening evenly in 2 to 3 stages, and prohibit locking it down all at once. - Place the gasket centrally, prohibiting offset or tilting. -ely deformed flanges must be straightened or replaced; gaskets cannot compensate for large deformation errors.

II. Problem 2: Metal-wound gaskets blown out, damaged, or delaminated Field phenomenon: The gasket is blown out during equipment pressurization, the metal strip becomes loose, and the graphite falls off, resulting in complete failure. Core causes - Main cause: Wrong gasket structure selected! A-wound gasket without an inner ring was used for high-pressure and instantaneous pressurization conditions. - Large pipeline pressure impact and excessively rapid instantaneous pressurization. - Gasket inner diameter too large, leading to a large unsupported area and insufficient pressure resistance. Solutions - For high-pressure, pipeline, and dynamic pressure conditions, a metal-wound gasket with inner ring must be used; the inner ring can support the gasket, resist impact, and prevent blowout. - Rapid pressurization of equipment is strictly prohibited; pressurization must done slowly with a gradient. - Strictly match the gasket specification to the pipeline diameter; do not use gaskets with an oversized inner diameter. 

III. Problem 3: G crushed, collapsed, or seal failure Field phenomenon: No leakage immediately after installation, but after running for a period, the gasket is severely crushed, loses its elasticity, and leaks directly upon second startup. Core causes - Excessive bolt force and torque cause over-compression, directly collapsing the graphite-metal layer structure. - Flange gap is too small, the gasket to be rigidly crushed. - Using ordinary thin gaskets for heavy-duty, high-pressure conditions. Solutions - Violent bolt tightening is prohibited; follow the principle "even, light pressure, and maintaining flatness". - For high-pressure and heavy-duty conditions, select thickened, high-density wound gaskets. - Collapsed gaskets absolutely not be reused; they must be replaced with new ones.

IV. Problem 4: Seepage and leakage after high-temperature operation (no leakage in cold state, leakage in state) Field phenomenon: Pressure test at ambient temperature is fully qualified, but slight seepage and leakage occur as soon as the temperature and pressure rise. Core reasons In thermal expansion coefficients of metal, graphite, and bolts lead to bolt loosening and a drop in preload after high-temperature operation, causing the gasket contact gap to open and resulting in hotstate leakage. This is the most typical hidden problem of spiral wound gaskets. Solutions - After high-temperature equipment has operated for 1-2 hours, hot-state-tightening and pressure compensation must be performed. - For high-temperature conditions above 300°C, 304/316 stainless steel spiral gaskets should be prioritized to avoid high-temperature loosening and aging of ordinary materials. - Prohibit one-time cold locking; reserve margin for thermal expansion. 

V. Problem5: Graphite detachment, powdering, and blackening of the medium Field phenomenon: Graphite on the gasket surface detaches and flakes off, the medium turns black, and graphite powder in valves and filters. - Use of inferior low-purity graphite winding layers with loose structures. Core reasons - Impact by hard objects, hand-tearing, pulling the gasket during installation. - Lack of outer ring positioning, causing the gasket edges to be loosely loaded. Solutions - For standard operating conditions, select high-p graphite   precision metal winding structures. - Handle with care during transport and installation; prohibit impact and friction. - For scenarios requiring wear resistance and anti-detachment, select metalwound gaskets with inner and outer rings for a more stable overall structure. 

VI. Problem 6: Crooked gasket installation, deviation, and sealing misalignment Field phenomenon: The gasket appears to installed, but it never seals tightly, is locally suspended, and has long-term micro-leakage. Core reasons - Gaskets without outer ring limits are prone to during installation. - Inconsistent force applied by multiple workers during the tightening process causes gasket displacement. - Flange hole deviation or misalignment. Solutions - For general piping flange applications, prioritize spiral wound gaskets with outer rings, which have built-in positioning functions and will not deviate. - Observe the gasket position at all times during the tightening process adjust immediately if deviation is found. - If flange misalignment is severe, the flange must be corrected. 

VII. Problem 7: Short service life and frequent replacement Field phenomenon:askets can last a year at other sites, but fail within two to three months at this site. Core reasons - Incorrect application matching: Using ordinary carbon steel spiral wound gaskets corrosive media. - Using low-temperature ordinary graphite gaskets for high-temperature conditions. - Large pressure fluctuations, using gaskets without support or inner/outer rings. Solutions Regular water, air, low temperature, and low pressure: Ordinary graphite spiral wound gaskets. - High temperature, steam, and high pressure: 304 stainless steel spiral wound. - Chemical corrosion, acid, and alkaline media: 316L stainless steel spiral wound gaskets. - Piping, anti-washout, and anti-deviation: and outer ring combination spiral wound gaskets.

Summary: Core Mnemonics for Spiral Wound Gasket Failure No ring leads to blowout, no outer ring leads to misalignment, excessive force leads to collapse, high temperature requires, incorrect installation leads to leakage, and wrong material leads to damage. Metal spiral wound gaskets seem simple, but they are actually very detail-oriented. Most leakage, failure, and premature issues can be completely eliminated by choosing the right structure and material, and following standard installation procedures, which significantly reduces maintenance and rework costs. If you are unsure about the pressure,, medium, or flange type, please leave a message, and I will help you accurately match the most suitable metal spiral wound gasket model.