Spectacle Blind Flanges are not real flanges but seperation sectors which can be inserted between two flanges to interrupt the flow of the fluid in a section line. They are manufactured in an 8-shape with one blind hole which can be replaced by the other in order to cut out the pipe section below the joint. They are only used with low nominal pressures for obvious sealing reasons.
Size: 1/2inch to 60inches
Rating: Class 150 to 2500
Dimension standards: API 590 Dimensions to suit ASME/B16.5/B16.48