When you are in charge of a vessel that weighs 20,000 tonnes, being able to see where you are going is crucial. If that vessel is a passenger ferry, sailing in bad weather—with spray lashing the ship—an effective set of wipers is a must. And yet it’s an area that has not seen much development over the years. One company, DuroWipers, is standing out though, with a solution that is set to save lives, as Breakthrough magazine found out.
In the marine sector, there are three designs of wiper used to keep the windows clear on commercial vessels. Round wipers, known as clear view screens, are the oldest and potentially simplest design. They are fitted within the glass and rotate to clear an area typically a foot in diameter. Straight line wipers have a mechanism that usually runs across the full width of the top of the window, moving the suspended wiper blade across the glass in a straight line. The third type, pantograph wipers, use a pair of parallel arms for the blade. The geometry of the arms can transfer the rotational motion of a motor powering it, to a linear sweep of the blade. As a result, the wiper can cover the majority of the window.
Each design has disadvantages. The round wipers are relatively small, clearing a limited portion of the window they are fitted to. While they are effective at clearing the screen, they have bulky motors and a rim which are attached to the glass, creating an obstruction.
The straight line design is probably the most common wiper in use today. But they are often expensive to maintain. Because the mechanism is fixed on the outside of the vessel it is exposed to water—corrosive saltwater—and potentially sand. Due to the design of a straight line wiper, this can get into the mechanism and over a relatively short space of time can cause issues.
The pantograph is a relatively basic design and is often not as effective as the straight line wipers. They have remained undeveloped for around 50 years, and so have a poor reputation. But, that is now changing thanks to DuroWipers.
DuroWipers was founded by Noel Gould, an engineer who, before starting the business, had worked within the marine sector on a few occasions. When he discovered that the performance of all of the wiping options left something to be desired, he realised there was an opportunity.
Noel explained why the pantograph design was chosen as a starting point: “I wanted to create something that was better than anything on the market at that time. I felt the pantograph design had the most potential as it was so underdeveloped. Plus the fact that the bulk of the mechanism could be fitted inside the vessel meant that it would be much easier to manage the issues faced by straight line wipers.”
At the heart of the DuroWipers design is what sounds like a simple development, but it is something that makes a big difference. On traditional pantograph wipers, only one of the two arms is powered. The second arm is passive. All it does is perform the geometric function needed for the wiper blade’s movement.
Noel decided to power both arms. It was a seemingly simple change but one that brought many advantages.
Firstly the design generates a more powerful stroke, overcoming one of the weaknesses of the traditional pantograph. The stroke is also smoother because the passive arm on the traditional design is being pushed and pulled by its powered partner. On the DuroWipers design, thanks to both arms being powered, the whole mechanism comes to an almost imperceptible pause as it reaches the end of a stroke.
As well as a quieter mechanism—an advantage on a vessel where the crew work in shifts and some may be trying to sleep—this smoother operation has a positive effect on maintenance requirements because less stress is placed on the components.
Eliminating maintenance requirements was high on the list of criteria for the design, and this was helped further by the use of two identical arms, rather than the traditional approach of having a more flimsy item for the passive arm. Noel and his colleague then decided to take all adjustment options out of the arms and opted to make each set of wipers to order. Taking out this adjustability has the effect of removing weak spots and areas that can wear over time.
The resulting design has, in fact, enabled DuroWipers to offer a three-year warranty as standard on all its systems. This is unheard of in the marine sector, and it is the only company that does this.
It is this reliability that has helped DuroWipers to gain an impressive client list which includes the Royal Navy, the RNLI and ferry operators such as DFDS.
Noel believes that the DFDS contract highlights an interesting trend. He said: “We find that it is the vessel operators that want our products rather than the builders of the ships. While our DuroWipers are not particularly expensive, shipbuilders are always looking for the lowest cost option with less relevance being given to longer term benefits. The operators, however, place much more importance on the impact of maintenance.”
For DFDS the advantages were clear. Its ferries serving the Dover to Dunkirk route work around the clock with only 45 minutes in port between sailings. So the only time that maintenance on wipers could be carried out is during a vessel’s scheduled annual maintenance.
For the Royal Navy, the reduced maintenance requirements helped with its need to carry enough spares to be able to operate for extended periods of time without returning to a home port. Indeed, DuroWipers is so confident in the quality of its product that it has given the Royal Navy something no other company in the industry is able to—a lifetime warranty.
The warranty has also been extended for the RNLI, on a contract that was not at all easy to win. It took three years of testing for the RNLI to satisfy itself about of the performance and reliability of the DuroWipers product, and now the wipers are specified on the new Shannon class lifeboat, of which 57 are planned to be built in the coming years.
Hearing the DuroWipers story makes you stop and think about how many other products are underperforming, but are tolerated because ‘that’s the way it’s always been’. All it takes is a fresh perspective and the desire to improve on what has become the accepted norm.
Published by Breakthrough magazine http://breakthroughpress.co.uk/