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Custom fittings

8 REPLIES 8
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Message 1 of 9
khobart
963 Views, 8 Replies

Custom fittings

I've been trying to figure this out for about an hour now and no luck.  I have a 10" ss pipe that circles the building which is oblong.  This calls for more than a dozen mitered fittings.

 

I've tried doing it through content builder but and not seeing an option to rotate half the fitting to correct angle that I need.  For the first custom fitting its about 9 degrees.  

 

Would using cylinders to create the fitting and then unioning them together be a way to go about it?  Only issue that I see with that, is it won't be a true fit to the pipe.

 

Any suggestions?

 

Thanks 

8 REPLIES 8
Message 2 of 9
nestly2
in reply to: khobart

You want to use cut-back weld elbows... correct?  Make sure the custom part flag is checked for the fitting in Content Builder.

 

MEP custom size flag.jpg

 

MEP CustomFittings.gif

 

 

Message 3 of 9
Keith.Brown
in reply to: khobart

In addition to the above solution you can also create a custom pipe fitting.  Create a path that the fitting will follow and then type pipecustomfitting at the command line.  It will ask you to choose the path and then show a dialog which allow you to set the diameter of the fitting.  You can miter your fitting if you need to.

 

This is a quick and easy way to create a custom fitting.

Message 4 of 9
khobart
in reply to: khobart

Ok,

 

Scratch that.  We are going to miter the pipe and use flange connections.  How can I set flanges at these odd angles and have the pipe correctly attach?  It either tries to insert a custom fitting or the pipe doesn't connect to said flange.

 

Thanks

Message 5 of 9
Keith.Brown
in reply to: khobart

When routing pipe do you happen to have the compass on?  If you do it will only allow you to snap to angles that are present on the compass and can cause complications when trying to route pipe that does not correspond to these angles.  In other words, try turning off the compass when routing weird angles.

 

Additionally make sure that your tolerance is on.  ( i think the setting is on although it might actually have to be off.  I always get confused and just toggle it!)  The tolerance is what allows the pipe to deviate from being completely parallel to the fitting and the max angle of deviation is controlled by the Angle of Deflection parameter on the fitting.  Turning the tolerance on or off allows the software to respect or not respect this Angle of Deflection.

 

Playing around with these two settings "Should" allow you to get the layout that you want.  But be careful, if you are trying to create angles with straight pipe and flanges then you will probably always get the behavior that you are seeing.  That just does not work in the real world.

Message 6 of 9
nestly2
in reply to: khobart

In theory, you would change the angle of deflection for the 2nd connector (AOD2) on the flange, however in the real world, you probably won't be able to get more than 2-3 degrees on a 10" SOF because the OD of the pipe is restricted by the bore of the flange. You can modify the flange or the pipe end, but in my field, it's easier to just cut a fitting.

 

content builder AOD.jpg  10AOD.jpg

Message 7 of 9
nestly2
in reply to: nestly2

Also, the default Slip On Flanges are not designed correctly in AMEP.  They have a 0 connection length, which 1) would never happen in the real world, 2) display incorrect pipe cut length, and 3) do no connect correctly when deflected.because the end of one side of the pipe comes completely out of the flange.  You either have to modify the flange, or you can use a Socket Weld, which will properly deflect 3 degrees using the out-of-the-box flange.

Message 8 of 9
Keith.Brown
in reply to: nestly2


@nestly wrote:

Also, the default Slip On Flanges are not designed correctly in AMEP.  They have a 0 connection length, which 1) would never happen in the real world, 2) display incorrect pipe cut length, and 3) do no connect correctly when deflected.because the end of one side of the pipe comes completely out of the flange.  You either have to modify the flange, or you can use a Socket Weld, which will properly deflect 3 degrees using the out-of-the-box flange.


We have also discovered the issue with the slip on flanges and incorrect cut length.  Our solution was to change the CEL to 0 and move the connection point to inside of the flange.  This will make the graphics incorrect but the cut length will now be correct.

 

The issue with flanges and cut length is that it appears to add 2x's the engagement length to the cut value instead of 1x.  You cannot really fix this using property sets because the flange is anchored to the pipe and reading property set information through flanges only works in one direction.  So if you schedule the pipe there is no way to read information about the flange CEL which lead to us just moving the connection point to inside of the flange.  Which by the way was how we did it for all fittings before Autodesk created the CEL parameter a few years ago.  The graphics for the pipe inserting into the flange will just be a little incorrect but your cut length will be spot on.

Message 9 of 9
nestly2
in reply to: Keith.Brown

I'm sure I had a discussion with Joshua B. about the SOF connection problem so I know Autodesk is aware as well.  (I couldn't find the thread though?)

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