Spectacle Blind Before Or After Valve

A spectacle blind is a steel plate cut into two discs of a certain thickness.

Spectacle blind before or after valve. 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 or spec blind abbreviated as sb is a safety device used to isolate a section of line or piece of equipment when the line or equipment needs to be inspected or removed from service. It is different than a valve in that the blind is a permanent or long term isolation device. These standard dimensions are also tabulated here.

As soon as the pipeline is drained the cam mechanism can be opened by turning the screw or handwheel now the spectacle plate can be turned and positioned and finally the cam. What is line blind valves. Blinds spaces and spectacle blinds are used for the purpose of positive shut off of a piping system where mere shut off using valves is not sufficient as valves are prone to leakage. The usual practice for line blinding by using typical materials such as spectacle blinds spool piece blind flange valves etc.

Standard dimensions of a spectacle blind. The device will be used when driving and the gate valve should be installed in the pipeline that does not pass through the medium after driving normally. A line blind valve is permanently installed into a pipeline. Spectacle blind a solid circular plate connected to a.

Block valve a valve that controls the passage of a liquid through a pipe with the intention that it permits either full flow or no flow. These are generally used in hazardous services like hydrocarbon fluids. Asme b16 48 covers pressure temperature ratings materials dimensions tolerances marking and testing for operating spectacle blinds or 8 blinds in sizes nps 1 2 through nps 24 for installation between asme b16 5 flanges in the 150 300 600 900 1500 and 2500 pressure classes. Spectacle blind for isolation posted in industrial professionals.

Piping engineering piping fittings blinds spacers spectacle blinds single line blind or blank. Spectacle blinds are generally applied to permanently separating pipesystems or just to connect with each other. Bolts can be re assembled and tightened it is necessary. Line blinding has been used to pipelines in various industries wherever either positive shutoff is most concerned or full flow should be achieved without pressure drop.

The valve s internal cam mechanism allows to change the plate from open to closed position within a minute. With gaskets inserted between flanges has however been labour intensive.