Development of novel folding propeller for sailing yachts

根据《今日航海》杂志(2011年9月)的说法，固定叶片螺旋桨被认为会使风帆下的航速降低0.5-1.0节。因此，许多帆船船主使用折叠式螺旋桨，因为它们最大限度地减少了帆船上不必要的阻力。尽管折叠螺旋桨在市场上占主导地位，但与折叠螺旋桨相关的一些问题使其无法完全满足航行消费者的需求。首先，折叠螺旋桨有在设计寿命结束前丢失工作部件的名声，导致船主需要更换设备。众所周知，现有推进器的重量会影响轴支撑联轴器中包含的无肘橡胶轴承的寿命。最后，由于反向推力不足，在码头或泊位内或靠近码头或泊位的操纵变得更加危险。折叠螺旋桨的价格可能是标准固定叶片的3倍。Super Prop Ltd.是一家初创公司，旨在开发能够生产出能够解决上述客户问题的新型螺旋桨的专业加工技术。他们的概念解决方案通过Micro Metalsmith Ltd.30多年来开发的专业熔模铸造方法实现。SuperProp螺旋桨的重量将比竞争对手轻30%，成本低50%，平均延长寿命约25%，并将通过具有复杂的叶片形状产生更大的推力，而通过常规的数控加工方法很难生产出这种形状。

According to Sailing Today Magazine (Sep 2011), fixed blades propellers are known toreduce speed “under sail” by a considerable 0.5-1.0knots. Therefore, many sail boat ownersuse folding propellers, as they minimise the unwanted drag induced on a sailing boat. Despitethe predominance of folding propellers in the market, there are a number of issues associatedwith the folding propeller that prevent it from fully satisfying the needs of the sailingconsumer.Firstly, folding propellers have a reputation for losing working parts before the end of theirdesign life, leaving the boat owner needing a replacement device. The weight of existingpropellers is known to affect the life of the cutless rubber bearings contained in the shaftsupport coupling. Finally, since reverse thrust is less than adequate, manoeuvring within orclose to a marina or a berth becomes significantly more treacherous. Folding propellers can beup to 3 times more expensive than standard fixed blade.Super Prop Ltd. is a start-up company, set up to exploit specialist processing technologycapable of producing a novel propeller that can address the aforementioned customer issues.Their concept solution is enabled through a specialist investment casting method developedover 30years by Micro Metalsmiths Ltd. The SuperProp propeller will weigh 30% less than itscompetitors, cost 50% less, have an average extended life of approximately 25%, and willproduce more thrust by having a complex blade shape that is extremely difficult to produce bynormal CNC machining methods.