The ZSH(DR)OY series metal-seated ball valve uses a two-piece construction for small sizes and a three-piece construction for large sizes. Its full-bore ball provides a high flow coefficient and low resistance in a simple, compact and lightweight structure. The ball is weld-overlaid or coated with nickel-based alloy or tungsten carbide for a smooth, wear-resistant surface; the stainless-steel seat is hard-faced with cobalt-based alloy or other hard alloy for reliable sealing, long life and strong shutoff performance. It is widely used for isolation in petroleum, chemical, metallurgical and paper-making services containing solid particles or involving high temperature and high pressure. High-performance double-piston rack-and-pinion or scotch-yoke pneumatic actuators, or electric actuators, may be used.