Name this fitting!

heidleml

Weil McLain piping diagram. Fittings on boiler supply look like bushings but I suspect they are a reverse thread fitting. I am having trouble finding the name of this fitting but would like to use them as opposed to unions if available.
Page 17
https://www.weil-mclain.com/sites/default/files/field-file/Weil-McLain_80-Series1_BoilerManual_550141935_1018.pdf

mattmia2

it is showing bolt together flanges like this:
https://www.supplyhouse.com/Ward-1B-BCF-1-1-4-x-4-5-8-Black-Cast-Iron-Screwed-Companion-Pipe-Flange

heidleml

@mattmia2 I am looking at the fitting screwed into the boiler. They are elsewhere in the piping diagram. E.g. on the tee of the header and a couple down on the return.

PC7060

I thought @mattmia2 was the winner of this quiz.
To save time, Please take a screen snip of the item in question and post to thread  

mattmia2

Either it is a reducing bushing or it is just the boss cast in to the boiler and tapped. you would have to look at the specs of the tapping sizes and the pipe sizes to see if it is being reduced. I'm pretty sure with the flanges and assuming a union or flange or that you are building the system after the boiler is in place, you can screw it all together as shown.

mattmia2

Looking at the diagram some more it may be a male-female reducer since it specs the outlet at 2" and the riser as 3".

HVACNUT

This?I think it's what @mattmia2 said. Bushing out of the block, nipple, flange.
I don't know what the "2 threaded joints rotate horizontally" means. 

mattmia2

HVACNUT said:

I don't know what the "2 threaded joints rotate horizontally" means. 

"2 threaded joints horizontally" is a swing joint so the header and the boiler can expand independently so the header expanding or contracting doesn't pull the sections of the boiler apart.

Steamhead

Looks like a bushing to me. However, only on the 3-80 and 6-80 models does W-M allow bushing the 4" tapping down to 3". @heidleml , what model do you have?

heidleml

@steamhead 780. We will be piping out in 4" so no need to bushing down. I guess I thought too hard on those fittings 🤷‍♂️ . I guess the note on vertical and horizontal movement is to clarify the need for threads and not welds. Thanks all for the insight!