Surface finish specifications for LNG valve sealing surfaces typically require 16 to 32 micro-inch Ra smoothness preventing seal damage and ensuring effective sealing. Ball sphere and seat surfaces demand particularly precise finishing as surface imperfections create leakage paths or accelerate wear, compromising the zero-leakage performance essential for LNG service. https://globalsealstech.com/product-category/oil-gas-seals/api-6d-ball-valve-and-lng-seals/