Understanding Volvo Duo Props
Volvo propellers come in a wide variety of models, but for some boating enthusiasts, there is nothing better than their line of duo props. Volvo duo propellers are designed to provide watercraft with improved propulsion and better efficiency than can be delivered by some more traditional designs.
Pull or Push?
Most boaters probably think of a propeller-based motor as something that pushes the boat through the water. In truth, however, propellers function best when they are able to pull an object instead of push it. This is one reason why airplanes in the early days of aviation had propellers mounted toward the front, not the rear, of the plane. Having a propeller pull a boat, however, is not very feasible considering the fact that boats are generally designed to have their engines and motors mounted in the rear.
The duo prop is designed to deal with this limitation of boat design. A duo prop system uses two propellers mounted together instead of just a single propeller. The two propellers that make up a Volvo duo propeller unit, however, are not identical. Instead, they are set up to execute counter rotation, which means that as one propeller rotates clockwise, the other one will spin counter-clockwise.
The advantage of counter rotation is that the amount of energy wasted can be reduced. This in turn leads to improved fuel efficiency. Improved speed and handling are other advantages that boating enthusiasts can enjoy from a duo prop system.
The Volvo Duo Prop in Action
Some marine propulsion systems use two propellers mounted at some distance from one another along the stern edge of a watercraft. Other dual prop systems take a different approach entirely, placing two propellers onto a single engine. This is the case with Volvo duo props.
First introduced in the early 1980s, Volvo duo propellers were a true leap ahead in marine propeller technology. Volvo propellers using duo prop technology feature twinned propellers that rotate in opposition to one another in order to cancel out any lateral forces that may be acting on the watercraft. This essentially means that all the forces left tend to drive the boat forward instead of allowing it to veer to one side or the other.
Advantages of Volvo Duo Propellers
Because lateral forces are no longer an issue, these duo props provide boating enthusiasts with a faster rate of acceleration even as they optimize fuel use for better efficiencies. In addition to acceleration that may be more rapid by as much as a full third of the previous rate, Volvo duo props also increase the top speed that is possible for a watercraft. In some cases, this improvement has measured as much as 5%.
Improvements in fuel consumption are equally impressive. When only a partial load is in play, fuel efficiency may be reduced by as much as 10%. At the same time, boaters will experience lowered levels of both noise and vibration, which helps to create a more pleasant atmosphere for everyone aboard.
Lowdown on Volvo Penta Propellers
When choosing a boat propeller most people concentrate on the diameter and pitch and while these are important there are other factors to consider when looking for a good propeller that will be sturdy, give good performance and maximize engine performance. Volvo Penta propellers have been known for decades as some of the finest propellers for discerning boaters. Over a year of design work goes into the creation of each Volvo Penta propeller and their current line of propellers have options for every type of boat and any application or use.
Volvo Penta propellers come in 3 and 4 blade options as well as 2 blade options for smaller boats with engines ranging from 5hp up to 40hp. Volvo Penta also makes a unique folding blade for sailboats that reduces drag by up to 8 times compared to fixed 3 blade propellers when under sail. Materials available include stainless steel, aluminum and a nickel-aluminum-bronze alloy to retard growth and for excellent corrosion resistance. Both cupped and raked blades are available for high speed applications and superior lift.
Perhaps the most interesting offering is the Volvo Penta Duoprop, a dual propeller solution with twin counter rotating propellers. The Duoprop was introduced in 1982 and has been a revolutionary design in the boating industry. Volvo Penta Duoprop propellers provide several benefits including:
- Faster acceleration by up to 30% versus single propellers
- Lowers fuel consumption by 10-12%
- Faster planing
- Lower vibration and noise levels
- Better maneuverability in all situations because the dual props put all their energy into moving the boat forward, unlike conventional single propellers which have to fight lateral forces
You and your boating pleasure deserve the best and the engineers at Volvo Penta have designed their propellers to provide the best performance no matter what type of boating or sailing you do. Perfecting standards in manufacture ensure reliable performance from every Volvo Penta propellers and since Volvo Penta propellers are perfectly matched to engine characteristics and drive hydrodynamics you will get the best fuel efficiency and maximum efficiency from every type of Volvo Penta propeller. Plus all Volvo Penta propellers come with 1 year warranty to be free from defects in materials or workmanship. All things together, Volvo Penta is a company built on history, tradition, technology and Eco-friendliness that works to give each and every boater a great experience with their propellers through rigorous research, design and testing.
Volvo Duo Prop Type T: Advantages
Volvo Duo Props Type T are engineered and designed for use with IPS drives. Unlike many other propeller systems that are fashioned out of stainless steel or aluminum, Volvo Penta Duo Props Type T are made from a carefully formulated mixture of three metallic substances: nickel, aluminum, and bronze. Nickel and aluminum are pure metals – indeed, they are elements on the periodic table students learn about in chemistry class. Bronze, however, is an alloy of copper mixed with other metals, tin among them.
This substance is called Nibral and it has properties that make it ideal for use in a high quality propeller such as those manufactured by Volvo Penta in their duo props line. Nibral, for example, is able to withstand corrosion, which means that a purchase of a Volvo Penta propeller in the T series can help to yield a propulsion system that will last for many years. In addition, the use of a strong material such as Nibral combined with a well-thought-out design means that Volvo Penta duo props Type T can provide outstanding performance during its long lifetime.
Sea water and metal can sometimes combine to produce an electrical charge, which can interfere with the full use and enjoyment of a propeller. Such a charge can also contribute to corrosion. However, the use of the Nibral alloy ensures that the propeller is optimally isolated from electrical charges.
As with all Volvo Penta duo props, the type T series is backed up by an extensive warranty by Volvo Penta.
Volvo Penta Duo Props Type F: The Stainless Steel Advantage
Volvo Duo Prop Type F has been designed for use with the DPS Drive. This drive can also be used with Type D duo props from Volvo Penta. The two duo prop systems are similar in several respects; for example, both can be used with gasoline engines and with diesel engines. However, there are some important differences between them but the Volvo Duo Props Type F and the D series are in the same line.
Aluminium vs. Stainless Steel
The first major difference is that while Type D duo props are made from aluminum, Type F Volvo Penta duo props are manufactured from stainless steel. Since they are made of solid steel, the Type F duo props feature stronger blades; in particular, they have more torsional strength than the blades on Type D duo props. Their fabrication from stainless steel also makes Type F Volvo Penta duo props better able to resist the damage that cavitation can cause.
In addition, the use of stainless steel for Type F duo props means that the blades themselves can be thinner than those on Type D duo props. This is because it requires less stainless steel than aluminum to resist the same amount of force. The blades on Type F duo props are therefore better able to efficiently transmit force.
The Type D duo props are only designed for use with watercraft going up to 35 knots. The Type F duo props are more appropriate in situations where the boating enthusiast wishes to travel at speeds in excess of 35 knots.
Volvo Penta Duo Props: Type G
Many boat propeller systems have blades made out of either aluminum or stainless steel. There are also more options available that may be more appropriate for some propulsion systems. Volvo Duo Prop Type G is made of Nibral, a term which refers to an alloy of nickel, aluminum, and bronze. Bronze is an alloy in and of itself, consisting mainly of copper, with other metals such as tin present in smaller amounts.
Volvo Duo Props Type G have been specially engineered and designed so that they will work well with the D4 as well as the D6 engine, both of which produce a stupendous amount of power coupled with significant torque as well. Not every propeller can withstand the forces generated by these powerful engines, but Series G in the Volvo Penta duo props line is fully up to the task.
Characteristics of Nibral
Volvo Duo Props Type G Nibral is an excellent material to use in boating applications because one of its key characteristics is outstanding resistance to corrosion. This alloy of nickel, bronze, and aluminum also allows for full isolation of electrical charges so that no growth of them is possible. This feature also adds to the corrosion resistance capabilities of the blades.
Like all Volvo Penta duo props, the Type G line is backed by a warranty that demonstrates the faith that the Volvo Penta company has in their line of fine boating products. Such a warranty is important so that customers know they are purchasing a quality product.
Volvo Penta Duo Props Type E: For DPX Drives
Volvo Duo Prop Type E have been specially designed and engineered to be able to work well with the DPX drive. This drive produces high speeds and makes substantial demands on any propeller system paired with it, but Volvo Duo Props Type E are up to the challenge. They can withstand speeds as high as 75 knots – these speeds are almost 50% higher than the speeds that other series’ of Volvo Penta duo props can handle. This fact alone should be enough to tell novice and advanced boating enthusiasts that the choice of propeller system really does make a difference in how the watercraft will be able to perform.
Duo Props Type E from Volvo Penta are fashioned from stainless steel, a very strong metal that will provide boaters with years of worry-free enjoyment. Part of the reason why these props are able to tolerate high speeds is because of the care exercised during manufacture. The blades are precisely balanced to produce ideal propulsion with a minimum of cavitation and other factors that can interfere when blades are even slightly out of balance.
Like all Volvo Penta Duo Props, the Type E series is backed by a solid warranty that demonstrates the faith that Volvo Penta has in its propeller products. The company has “put its money where its mouth is,” so to speak, by offering a warranty with extensive terms that will allow boaters to have confidence in their propeller purchase.
Volvo Penta Duo Props Type D: Die Cast Quality
Volvo Penta Duo Props Type D are made of aluminum, a lightweight and corrosion-resistant metal that helps engines achieve high fuel efficiency due to decreased weight for the propellers. Volvo Duo Props Type D can be used with engines that run on either gasoline or diesel fuel and are specifically intended for use with the DP-S drive. These duo props offer speeds as high as 35 knots.
Features of Volvo Penta Duo Props Type D
Each of the propellers on these duo props has been expertly die cast. This is important because when the blades of a propeller have been die cast, they have a more slender profile than blades that were fabricated using a sand casting method. Slimmer blades lead to reduced levels of cavitation as well as a longer effective life.
In addition, boaters will find that they the aluminum propellers on these duo props are dynamically balanced for high efficiency and excellent performance.
Type D Volvo Penta Duo Props, like all Volvo Penta propeller systems, are backed by the company’s excellent warranty, which guarantees the quality of the materials used as well as the workmanship that went into constructing the propellers.
Cautions for Volvo Penta Duo Props Type D
Boaters should be aware that Volvo Penta duo props are not always interchangeable. In the case of Type D duo props used in twin installations, the D series should not be combined. Only the same propellers should be used in twin installations.
Stainless Steel Volvo Penta Duo Props Type C
Volvo Penta Duo Props Type C work with drives numbered both DP280 and CP290. All Type C Penta duo props are fashioned from stainless steel, which as experienced boaters know, has several significant advantages. Stainless steel is resistant to corrosion, meaning that rust issues will be reduced. In addition, stainless steel is a strong metal – this helps the blades on the duo prop to resist all sorts of damage from warping to scratches. These duo props are engineered to produce maximum thrust when speeds exceed 40 knots, making them an ideal choice for boating enthusiasts desiring a high performance, state-of-the-art propulsion system.
Volvo Duo Props Type C produce this outstanding performance in part because they have been engineered to have blades that are thinner than is typical of many other propeller systems. The stainless steel allows for large levels of torsional strength even at very high accelerations. Stainless steel also means that the units are resistant to the various kinds of damage that can be caused by cavitation. In addition, the stainless steel of these props gives them a clean, gleaming look that will be an asset to any type of boat. They not only consist of quality materials – they look like it.
Type C Volvo Duo Props also come with Volvo’s excellent warranty so that customers can feel assured that they will be able to enjoy a quality boating experience for many years to come.
Advantages of Volvo Penta Duo Props Type B
Volvo Penta Duo Props Type B are made of aluminum. Like all duo props, they feature two sets of rotating propeller blades rather than one set. Each set of propellers rotates in a different direction from the other: if one is rotating clockwise, for example, the other will rotate in a counter-clockwise direction. This design feature does not eliminate 100% of all cavitation, but it comes remarkably close so that in practical terms, concerns about cavitation can become a thing of the past.
Volvo Duo Props Type B work with DP280 and DP290 drives and were specifically designed so that the comfort of boat passengers could be increased even as very high revolutions of the propellers delivered the surges of raw power that are needed for top speeds and fast acceleration.
Each propeller on a Volvo Duo Props Type B has three blades, and each blade features an ultra-thin profile. Constructing these blades requires high-precision manufacturing, and Volvo stands behinds their products, backing them with a warranty so that customers can feel confident that if problems do occur, Volvo will be there to help. The warranty is also proof, however, of how unlikely it is for problems to arise. Volvo produces quality duo props and has no hesitation in offering warranties with generous and extensive terms.
Since many Type B duo props are produced by Volvo, be sure to consult a propeller guide that will help you choose the individual unit that is right for your watercraft and engine.