Metal spiral wound gasket sealing mechanism

2013-12-12


Metal spiral wound gasket industrial apparatus pressure vessels, process equipment , power plant and connecting pipes and other removable seal -shaped main connection type, usually consists of flanges, bolts, nuts and metal spiral wound gasket composition, called bolts flange connection, working conditions at their very complex fluid medium to be sealed variety, to prevent liquid or gas through a metal spiral wound gasket seal leaking joints are the most important and most difficult task facing the plant . Although the metal spiral wound sbr gasket with rotary mechanical shaft seals, reciprocating mechanical shaft seal , valve stem seals compared to the leakage rate is not great, but the metal spiral wound gasket wide range of large , so they become the industry equipped main source of leakage. Leakage ranging from causing a lot of wasted energy, raw materials , heavy equipment lead scrap, downtime , casualties and serious environmental pollution.
1 . Metal spiral wound gasket sealing mechanism
That media leaks from flowing outside the limited space inside or from the outside into the limited space inside the phenomenon of people who do not want to happen . That medium flow through the junction leakage sealing surfaces inside and outside space. The root cause leakage due to the contact surface there is a gap , and the pressure difference on both sides of the contact surface , the concentration difference is the driving force of the leak . Due to the impact of the sealing surface machining accuracy form and other factors , there is a gap between the sealing surface is inevitable, it will cause the sealing surface is not completely consistent , and thus leak. To reduce leakage , the contact surface must be fitted to the extent that the passage cross-sectional area to reduce the leakage , the leakage resistance is increased , and make the driving force is greater than the leakage . Queensland seal surface pressure is applied to the load to generate the pressing stress , can improve the degree of contact of the sealing surface , when the stress is increased enough to cause significant plastic deformation of the surface , can fill a gap between the sealing surface , plug the leak channel. The purpose is to use a metal spiral wound gasket spiral wound gasket materials under compression loads role more prone to plastic deformation characteristics , so that filled the tiny rugged metal spiral wound gasket in order to achieve the seal .