{"id":60446,"date":"2024-09-09T09:06:09","date_gmt":"2024-09-09T13:06:09","guid":{"rendered":"https:\/\/blogs.sw.siemens.com\/simcenter\/?p=60446"},"modified":"2026-03-26T06:37:10","modified_gmt":"2026-03-26T10:37:10","slug":"controllable-pitch-propeller-works","status":"publish","type":"post","link":"https:\/\/blogs.sw.siemens.com\/simcenter\/controllable-pitch-propeller-works\/","title":{"rendered":"How does a controllable pitch propeller (CPP) work?"},"content":{"rendered":"\n
Controllable pitch propellers (CPP) are a sophisticated type of marine propulsion system where the blades can be rotated to change the pitch. This adjustment allows for optimal performance under varying conditions such as load, weather and maneuvers, ensuring maximum efficiency.<\/p>\n\n\n\n
In this blog, we will dive into the components, operation and simulation results of a CPP system, providing a comprehensive understanding of its engineering. The sizing of the hydraulic circuit (actuator, valves, piping, etc.) during the preliminary design phase of a controllable pitch propeller system is done using Simcenter Amesim.<\/p>\n\n\n\n
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Components of a controllable pitch propeller<\/strong><\/h2>\n\n\n\n
In a simplified CPP system, we count the following key components:<\/p>\n\n\n\n
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Two pumps in parallel<\/strong> – they provide the necessary hydraulic power to the system<\/li>\n\n\n\n
Selecting valve<\/strong> – it selects the appropriate flow direction valve. By default, the main valve is used, while the second valve serves as a redundancy<\/li>\n\n\n\n
Flow direction valves<\/strong> – there are two proportional valves\u2014one main and one redundant. These valves control the hydraulic flow to the actuator<\/li>\n\n\n\n
Relief valves<\/strong> – they protect the system from overpressure by releasing excess pressure<\/li>\n\n\n\n
Counter-balancing valves (CBV)<\/strong> – they maintain stability within the hydraulic system<\/li>\n\n\n\n
Hydraulic actuator<\/strong> – it moves the blades to the desired pitch angle<\/li>\n<\/ul>\n\n\n\n
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In our simulations, the main parameters of the system are as follows:<\/p>\n\n\n\n
Hydraulic pumps<\/strong> – each pump has a displacement of 50 cm\u00b3 and operates at 1170 rpm<\/li>\n\n\n\n
Relief valve<\/strong> – tuned to a maximum pressure of 150 bar<\/li>\n\n\n\n
Flow direction valves<\/strong> – capable of handling 150 L\/min with a 1 bar pressure drop at maximum opening<\/li>\n\n\n\n
Main pipes diameter<\/strong> – 30 mm<\/li>\n\n\n\n
Hydraulic actuator<\/strong> – features a total stroke of 360 mm, a piston diameter of 300 mm and a rod diameter of 50 mm<\/li>\n\n\n\n
Total translating mass<\/strong> – 300 kg per blade, with a weight of 140 kg and an inertia of 6.42 kg\u00b7m\u00b2 for a single blade<\/li>\n<\/ul>\n\n\n\n
![\"\"](\"https:\/\/blogs.sw.siemens.com\/wp-content\/uploads\/sites\/6\/2024\/09\/image-5-1024x786.png\" "\\"Simplified")