It provides a permanent or long term isolation device. If a piece of equipment needs to be inspected or removed from service then the plate covers the ring to form an airtight seal which consequently isolates a section of line or the piece of equipment. Spectacle Blinds, Spades and Ring Spacers should be made from a plate or forging specification, approved for use by ASME B31.3, of essentially the same chemical composition as the mating flanges and piping involved. The diameter of them, is depending on the flange size, and the thickness from the Pressure Class of a flange.ĭimensions from Spectacle Blinds, Spades and Ring Spacers, you will find in the main Menu "Flanges"ĪSME B16.48 covers pressure-temperature ratings, materials, dimensions, dimensional tolerances, marking, and testing for operating line blanks in sizes NPS 1/2 - NPS 24 for installation between ASME B16.5 flanges in the 150, 300, 600, 900, 1500, and 2500 Pressure Classes.
The diameter always is slightly larger than the Raised Face of a flange by a correct assembly, the bolts are just not touched by the Blind or Spacer. The sealing surfaces of a Spectacle Blind, Spade or Ring Spacer are usually conducted in accordance with the Face Finish from the flange.
What should never lack is, that in the handle, the diameter and the Pressure Class of a Spade or Spacer is engraved this applies also for the Spectacle Blind. Therefore the handles are often specially marked, or both have a different design a customer often provides its own specification. After replacing the gaskets (new gaskets are to recommend), the bolts can be re-assembled and tightened.Ī small problem is that we basically can not see, or a Spade or a Spacer mounted between the flanges. By loosening of all bolts, and half of the bolts temporarily remove, the Spade or Spacer can be placed. So as for the Spectacle Blind already described, maintenance on a pipesystem can be a reason to temporarily replace a Ring Spacer for a Spade. After replacing the gaskets (new gaskets are to recommend), the bolts can be re-assembled and tightened. By loosening of all bolts, and partial removal of their, the Spectacle Blind can be rotated. This run will take place through the hole, that is drilled in the connection piece. Maintenance on a pipesystem can be a reason to rotate the spectacle in the "close" position. If the Spectacle Blind in the "close" position is rotated, the pipe is blanked off and no flow is possible. Normally, a Spectacle Blind is mounted in the "open" position so that flow through the pipe is possible. Spectacle Blinds be applied in systems, which regularly need to be separated from other installations.
One of the discs is a solid plate, and the other is a ring, whose inside diameter is equal to that of a flange. The two discs are attached to each other by section of steel similar to the nose piece of a pair of glasses. A Spectacle Blind is a steel plate cut into two discs of a certain thickness. Spectacle Blinds are generally applied to permanently separating pipesystems, or just to connect with each other.
0 kommentar(er)
