Here is a revolving pull up system that helps you add more intensity to your workouts. The Titan Fitness T-3 and X-3 Series Rack-Mounted Revolving Pull-Up System has room for 4 x 1.25-inch or 2-inch fat bars. You can go full 360 degrees or fix the position with a pin.
This revolving pull up bar system has 1000lb weight capacity. The above video shows how it works.