Metal seals for extreme LNG service utilize soft metal rings or precision-machined metal-to-metal contact surfaces achieving sealing through controlled deformation. These seals provide ultimate reliability in ultra-low temperature applications or emergency shutdown scenarios where polymer seals might be compromised, though requiring higher actuation forces and more precise surface fin... https://globalsealstech.com/product-category/oil-gas-seals/api-6d-ball-valve-and-lng-seals/