Freudenberg launches new crankshaft seal

Freudenberg-NOK Sealing Technologies has launched a seal designed to reduce fuel consumption and emissions in automobiles.

The firm's Low Emission Sealing Solutions initiative has produced Levitex, the first nearly friction-free crankshaft seal, according to the company.

Due to the gas flow structure on its contact face, the primary ring in the seal interacts with a mating ring to form a cushion of air upon which the primary ring floats independently. Air lubrication produces less friction than oil, the company claims, reducing frictional losses to a minimum, thus lowering fuel consumption and adding durability.

Karl Woll, director of the company's Product Pre-development Global Oil Seals Division, called the product a "small revolution in engine seals."

Levitex is extremely resistant to pressure, the company said, a quality important for advanced engines.

Freudenberg said a German auto maker, along with a university, are in the process of testing the new seal.

The European Union requires that emissions of every auto maker's vehicle fleet average 95 grams of carbon dioxide per kilometer by 2020, and Freudenberg said that the Levitex seal alone should save at least 0.5 grams of carbon dioxide. A 1.0 g reduction in carbon dioxide emissions equates to about 0.2 miles per gallon savings in gas for a vehicle rated at 33 mpg.

Freudenberg said the idea behind the seal originated from a corporate partner, Burgmann Automotive. Since the 1960s, Freudenberg said the Bavarian equipment manufacturer has produced gas-lubricated mechanical seals for industrial applications, especially in turbines. The seals feature rotary movement between the outer and inner slide rings that produces a cushion of air, allowing the seal to function nearly friction-free.

Soren Neuberger, Levitex project manager, said adapting the design for automotive mass production was too cost prohibitive. But then simulation software was developed to simplify the seal. Once the process was analyzed for risk, the first prototypes were tested.

The reconfigured seal had four individual parts instead of nine. Once the seal passed several tests, the first auto maker ordered prototypes for its own trials and found it to be successful. Freudenberg said the auto maker is interested in taking Levitex into regular production in 2017.

Freudenberg-NOK Sealing Technologies, a joint venture between Freudenberg and Co. in Germany and NOK Corp. in Japan, produces sealing technologies for a variety of markets, including aerospace; agriculture; appliance; automotive; construction; diesel engine; energy; food and beverage; heavy industry; and pharmaceutical.