Bunkai or the application of Kururunfa (Part 3) is as follows.

http://www.geocities.com/sanzinsoo/kururunfa3.html

PHOTO No.51: Assume the opponent throw a right middle punch. You
receive it with right middle block.

PHOTO No.52: You grab and grip you opponentfs wrist in your right
hand, and twist it counterclockwise. Do not release your grip until
finish.

PHOTO No.53: You turn to right 180 degrees. At the same time, you
put the opponentfs arm on your left shoulder. (The opponent is
behind you.)

PHOTO No.53: Your left shoulder is a fulcrum. The opponentfs right
arm is a lever. You pull the opponentfs wrist downward. Making
use of leverage, you give him pain.

PHOTO No.54: While you do this armbreak technique, you make a rear
elbow strike with your left elbow to his solar plexus.

Sanzinsoo