Pipe Coatings & Pipe Surface Finish

The Viking Johnson system relies on good uniform contact of the gaskets with the pipe surface, and the following need to be considered: –

Pipe Surface Finish

It is important to ensure that the pipe ends, in the areas where the coupling gaskets will seat, are free from loose surface deposits, bumps, dents, score marks, weld beads, flat spots and the like, or the full pressure capability of the coupling may not be realised.

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Pipe Coatings

Most pipes are finished with a coating of some description, which must be considered with determining the outside diameter to be used for the manufacturing size of the Viking Johnson fitting, or installation may be difficult or impossible.  In addition, the type of coating must be considered as it may adversely affect the performance of the fitting. Very thick pipe wrappings (typically several millimetres thick) must be removed at pipe ends so that the coupling will seat either on the bare pipe or on a high-quality thinner paint film. It is important that details of the intended pipe corrosion protection are made known to us when ordering so that the correct size of coupling can be produced.  Alternatively, we must be informed of the finished pipe diameter including all coatings, with appropriate tolerances.