The RIDGID R7111 VSR heavy-duty drill has an 8-amp motor, die-cast all-metal gearbox, and a 1/2 inch keyed chuck for maximum durability and high power. This device is frequently used for at-home projects or for large constructions jobs due to its versatility and long-term use.
I'll take a shot and guess you are referring to the drill chuck, which is what you want to remove. Instructions begin on page 13 of your user manual. If you don't have it, here is a link to the manual. Good luck.