What is the difference between bending & roll-bending ?

The  difference between bending and roll bending is,bending has an angle while roll bending has no angle.

difference of bending is a straight bending or sharp one bend jist like a angular bar,compare to roll bending,roll bending is a type of bend with a smooth curve like for example the pipe if we can curve it without using a welding machine to curvre it out,we must use a roller to keep it smoot and clean.and  one more a pressure tank and a water tank we will use a roll bending istead of bending

Roll bending uses rollers.