Loader drops material on top, grizzly bars deflect oversized out the back. Stuff that makes it thru the bars, but stays on top of the screen, also go out the back, and pile up together with the oversized ? Scalper 77C - A Portable Topsoil and Rock Screen - Screen Machine Industries The 77C is a compact, portable screener for rock and topsoil separation built heavy-duty to suit virtually any size job or feed material. www.screenmachine.com
The grizzly kicks off the big stuff that would damage the screen?
Yes, only material that passes through screens is conveyed on the discharge belt. The oversize can either be reloaded and screened again or carried away to a segregated pile. It is a scalper which means you are getting a single size end product unlike a screen plant which will give several different end products.
You would think......a guy could add a simple chute & barricade to take the grizzly stuff to one side, and the "top of screen" rejects to another spot "next door". Make 3 products.
That's the difference between a scalper and screen plant.