Quick leg elbow, dummy elbow

the quickleg 90 is a tee but still only has a 90 degree pattern internally,those dummy leg/pipe supports can be misleading in the field.
A cushion tee is similar except it is a butt weld fitting used in erosive services whereas a quickleg 90 is a socket weld/threaded fitting.

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The Difference Between Trunnions and Dummy Legs

The process piping world is packed with fun, and sometimes confusing, terms. At the top of the list aretrunnions and dummy legs. Because they’re often mentioned together, it is only natural to wonder, “What is the difference between trunnions and dummy legs?”

What Is a Trunnion?
A trunnion is a piece of pipe that you weld to vertical piping in order to add support. They’re usually welded to those
areas of the piping system that need a higher load-bearing capacity.

What Is a Dummy Leg?
IMG_MetalPipeSupportsA dummy leg is a piece of pipe that acts as a support branch between your pipe and a nearby
support point. It is generally either smaller than or the same size as the pipe you’re supporting. By welding these extra
pieces to your pipe run’s elbow, you essentially add a support wedge that fortifies a vulnerable point in your pipe system.