Wartsila CPP 4500mm 4B

The Wärtsilä CPP 4500 mm 4B is a 4‑blade, nickel‑aluminium bronze controllable‑pitch propeller designed for vessels requiring fine thrust control and rapid reversal at up to 150 rpm. The supplied category identifies it as Controllable-Pitch Propeller (CPP), and it is normally installed at the aft end of the propulsion shaft with a hub containing the mechanism that rotates the propeller blades about their own axes. In that role, its primary purpose is to vary thrust and reverse thrust direction without necessarily reversing shaft rotation. Compared with an FPP, a CPP adds blade bearings, a pitch-control mechanism and hydraulic or mechanical actuation, which introduces additional sealing and control maintenance. Within the supplied list, neighbouring variants are distinguished by their model designations and naming, while the source does not state further model-specific hardware differences. No additional performance, approval or construction detail is inferred from the model code beyond the information supplied in the source record. For exact ratings, dimensions, settings, capacities, materials and variant-specific limits, refer to the manufacturer documentation for the exact figure.