Numbering of connections/surfaces etc

Last comment 20/09/2018 17:07 by Marc
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Nico Schmid 5 years ago created
Hi Marc,

Are you aware of a general rule on how to number connections (i.e. classes "Fittings with n>1 connections"), or surfaces?
Many of the features (surface, DN, material, ..) are required for each connection separately, and we struggle to allocate them.

This issue with numbering also applies to surfaces and others. That's why I place this question in the general section.
Thanks very much!
Best answer — chosen by Nico Schmid
Marc Habets 5 years ago created
Hi Nico,

Nice topic you are touching here ?. This is one of the most difficult issues in ETIM to get unambiguous. In the Netherlands we had the guideline (for hydraulic/water products) that where the water/medium enters is considered connection 1 and then you count clockwise. That can work for pumps, some valves, etc. But for many fittings there is no fixed entry. So in the basic model that is very difficult and for sure will cause different interpretations by different manufacturers in some cases. Only guidance here is logic, choose what you feel is most obvious. 

In ETIM MC, where we have dimensional drawings to support a clear interpretation of the dimensional features, the problem is solved for the greatest part. If you look at this model for an Y-piece, the connections are clear for everyone, see But even ETIM MC can not give a 100% solution, for example this bend with 2 connections, see, you could see connection 1 and 2 different then someone else does. Because it is symmetrical you can turn it over and it still is the same drawing. 
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Topic started 20 September 2018 at 09:32
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