Spiral-directional inter-flanged gaskets
The concept of spiral wound gaskets (SWG) was proposed by Flexitallic in 1912. The goal was to meet the needs of US refineries in the first half of the 20th century, when process parameters - temperature and pressure - increased dramatically in this industry. This was a new milestone in reliable, safe flange sealing.
The importance of the axial resilience property of the gasket cannot be overemphasized. To ensure the reliability of the gasket in conditions of temperature and pressure surges, temperature differences over the flange surface in the radial direction, loosening of fasteners, an elastic gasket is required. Spiral-wound gasket is elastic in nature, and therefore it is successfully used on flange joints of pipelines, vessels, equipment connectors at the most severe parameters - at high temperatures and pressures and in conditions of corrosive and toxic environments.Основные потребители спирально-навитых прокладок - нефтеперерабатывающая, нефтехимическая, химическая, металлургической промышленность, а также традиционная и атомная энергетика.
Spiral-wound gaskets are made from V-shaped or W-shaped profiles and consist of alternating layers of metal tape and soft filler. It is recommended to use low-carbon stainless steel as the material of the tape in order to avoid cracking, for example, steel 03X17H14M2. The filler material used today is thermally expanded graphite in most cases, and fluoroplastic, if the environment is a strong oxidizing agent.
Depending on the design of the flanges, spiral-wound gaskets can have restraining metal rings, which are a compression gauge and therefore such a piercing cannot be overtightened and crushed. Also, the outer ring protects the gasket from blowing out.
Below are the types of gaskets according to OST 26.260.454 - 99. Western standards ASME 16.20 / ANSI 16.50 (API 601) have gaskets of similar types