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Flange coupling adapter vs. flange by MJ adapter.

Flange coupling adapter vs. flange by MJ adapter.

Flange coupling adapter vs. flange by MJ adapter.

To all,

Could someone please tell me what the difference is if any between a flange coupling adapter and a flange by MJ adapter is? Please tell me what each would be used for.

Civil G

RE: Flange coupling adapter vs. flange by MJ adapter.

The word "adapter" or adaptor is (IMHO) a sort of generic or proprietary device term, that does however imply a conversion of a factory or cut pipe spigot end to an in some configuration simulated flanged end (e.g. to allow a flanged piping or valve etc. item to be inserted into the line, and/or perhaps also in "field-adaptable" or cut-to-suit fashion, to also precisely locate the flanged end at a particular station on the pipeline).
While there are actually traditional, standardized fittings per first ANSI/AWWA C110 and then C153 standards called mechanical joint by flanged "connecting pieces", that can be used to do basically the same thing, some manufacturers/fabricators have developed various more compact and proprietary design "adapters" to basically serve the same function, but with much lesser (e.g. casting) weight and laying length involved in the transition at the plain end(s). These devices generally employ a sealing mechanism e.g. actuated by the eventual flanged bolting, and as traditional flanged ends are also restrained joints (and sometimes used e.g. at substantial thrust foci such as block or isolation valves etc.), also often some means of mechanically attaching the device to the plain end to be able to handle some level of axial thrust. The specifier should consider the designs, strength and also where necessary deflection abilities while maintaining seal (etc. compared to traditional flanges) of all such devices.

RE: Flange coupling adapter vs. flange by MJ adapter.

The flange coupling adapter adaptor is used where there is no space to remove the pipe spool. You can not move the adjacent pipe end laterally to enable the pipe spool to be removed.


RE: Flange coupling adapter vs. flange by MJ adapter.

A flange MJ (mechanical joint) adaptor is flanged socket. It provides a flexible connection between the flange and the pipe - if you need to do any maintenance in the future you can dismantle the mechanical joint and open the flanged joint by pushing the socket onto the spigot. However some pipe layers erroneously push the spigot into the full depth of the socket and when you come to do future repairs you may find that there is not enough clearance to open the flange joint and replace the gasket. A flange adaptor is also a flanged socket but it has a larger diameter than the spigot pipe that it connects to. When dismantled it can be slid over the spigot giving more clearance for dismantling and reassembly of the flange.

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