Introduction
In high-tech industries such as semiconductor fabrication, pharmaceutical production, and chemical processing, piping systems must handle aggressive media, extreme temperatures, and strict purity requirements. A critical component for safe isolation and maintenance is the figure-8 blind (also known as a spectacle blind or figure-8 blank). Unlike generic pipe blinds, the figure-8 design combines a blind plate and a spacer ring in one piece, allowing quick changeover between closed and open positions without disassembling the pipeline. This article provides a practical procurement guide for sourcing figure-8 blinds from Chinese manufacturers.
Standards to Confirm
When specifying figure-8 blinds, ensure compliance with international standards. Common standards include:
- ASME B16.48: Standard for line blanks (including figure-8 blanks) in sizes up to NPS 24 (DN 600) and pressure classes up to Class 600.
- ASME B16.5: For blank flanges, often used as reference for facing dimensions.
- DIN EN 1092-1: European standard for flanges, applicable if your project uses metric dimensions.
