2014-9-15 · It must be at least 36 in. wide for an 18 x 36 jaw crusher. So a 4-ft by 8-ft screen would be acceptable. The 1-in. screen is a second deck for the 38 tph from the jaw crusher, so the deck correction factor is 0.90 and that screen capacity is 2.1 x 0.9 = 1.89 tph/sq ft. The screen area needed under the jaw crusher is 38/1.89 = 20.1 sq ft.