The invention is a working device arranged in some place, composed of two or above working devices arranged in some place, back-to-back, side-arranged, opposite, staggered, side-by-side, up and down, rotatable, inclinable, turnable, movable, liftable or in other form. And an engineering machine applying it is composed by arranging it in corresponding position on a corresponding vehicle or chassis or connecting it with the correspond position. And it can compose various engineering machines by various vehicles or chassises, compact, multifunctional, low-cost, high-efficiency and energy-saving, and having strong practicality.