how to calculate vertical rolling angle & how to fit-up rolling elbow in (English)

this video explain about how to fit-up rolling elbow & how to calculate vertical rolling. if you want to more video related piping structural &tank
please subscribe my channel( AtoZ mechanical construction skills)
If you like to watch video in Hindi go to my next channel.
Al Zara mechanical in Hindi
/ @alzaramechanicalconst...

[@babunanadan1940]

Good

[@asikparadaiss618]

Tan inverse .not minus tan

[@charanteja6193]

Explanation not good..pls improve

[@yoursmanoj9162]

Wrong

[@tajuddinalam770]

Galat hai