Halyard makes a silent Discovery

Halyard Marine Ltd, leaders in the design and manufacture of marine exhaust silencing and engine noise reduction solutions, has designed and installed a bespoke exhaust system to Discovery’s newest luxury yacht, in order to create exceptionally low noise levels.

The elegant Discovery 67 yacht has been designed by renowned naval architect, Ron Holland, and built by British yacht builder, Discovery Yachts Ltd. Top quality materials and fittings have been used throughout the build to guarantee a luxurious and comfortable feel whether sailing the high seas or relaxing in the marina.

The minimization of noise and vibration is always the subject of a great deal of work on quality, long distance cruising yachts, which has led Halyard to work closely with Discovery to ensure that noise levels are drastically reduced, with general comfort for those on board increased.

Halyard has designed and built exhaust systems both for the Discovery 67’s propulsion engine and the generator. In both cases the wet exhaust systems have used Halyard lift silencers, feeding water separation units. These systems remove water from both exhausts and drain this under the hull, removing the “sploshing”, and reducing noise at the outlet by 80%. The effect is so dramatic that exhaust noise cannot be heard on the marina pontoon alongside the yacht.

Halyard’s silencers are made from filament wound GRP (glass reinforced plastic) tube, before being hand-laminated with flat sheet bases and finished with a gel coating. Halyard uses GRP as the base material of its HMI silencers to avoid the corrosion and acoustic problems of welded stainless units, and the low melting points of plastic silencers.

In addition, sound insulation material has been fitted to the Discovery 67 to reduce overall noise onboard. Halyard’s fire zero rated noise insulation is constructed using a multi layer construction for maximum effect, and adds a soft facing to hard bulkheads in order to absorb noise. Halyard has also supplied the yacht with the Aquadrive engine coupling system, designed to reduce vibration levels onboard by more than 50%. Manufactured by GKN Driveline and distributed by Halyard, Aquadrives enable free movement between the engine and shaft to prevent vibration from travelling along the shaft line.

Nigel Stuart, Managing Director at Discovery says, “Noise is crucial in order to maintain the quality associated with Discovery’s sailing yachts. Halyard has done a superb job in helping us to achieve the exceptionally low noise levels that our customers demand.”

Halyard is the only company in the world able to manufacture an entire exhaust solution from “turbo to transom” in-house. Service and support starts from the initial designs through to assistance during manufacture and installation, right through to final sea trials. Throughout any project the company’s integrated 3D CAD technology enables fast and accurate document and design exchange and delivery, anywhere in the world, to ensure the project is fully documented and recorded.

The Discovery 67 with Halyard's bespoke exhaust systems.