PTFE seal wins 2011 innovation award

Turcon M12, a PTFE-based material launched in 2011 by Trelleborg Sealing Solutions, has received a 2011 Innovation Award from Flow Control Magazine. According to the company, the PTFE-based sealing material has unrivaled performance in key hydraulic sealing characteristics such as friction, wear, and high-pressure operation. Testing shows Turcon M12 resistant to most media, including a broad range of lubricants, and has outstanding wear resistance and friction characteristics. The cost-effective material also provides an extended seal life, as well as a wide operating window in temperature, pressure, and velocity.

 “Turcon M12 has exceeded even our expectations,” said Trelleborg Sealing Solutions Product Manager Nancy Getz. “On most every parameter it is better than, sometimes significantly, than previously recommended compounds or was at least equal to them.”

Trelleborg Sealing Solutions
www.trelleborg.com

Seal material for hydraulics good to 270°F

A proprietary polyurethane compound, Zurcon Z25, has all the characteristics of the widely used Zurcon grade Z20 with an elevated operating temperature to 130°C or 270°F. Zurcon Z25 is recommended for hydraulic applications in which high-temperature performance is required due to an improved extrusion resistance and compression set. The material is ideal for use in heavy-duty cylinder sealing applications where it can guarantee a long service life. These include industrial and mobile applications with limited cooling or cylinders exposed to high-temperature painting.

Self-energizing, Zurcon Z25 operates at pressures to 40Mpa or 5,800 psi without a Back-up Ring. It is suitable for use in all hydraulic fluids and has a low compression set. It has an MDI (diphenylmethane diisocyanate) material base and is also suitable for rotary applications such as swivel joints, where heat is generated by high pressures and low speeds.

Trelleborg Sealing Solutions has also developed Turcon M12, a PTFE based sealing material for key hydraulic sealing characteristics such as friction, wear and high-pressure operation. Extensive testing has shown that Turcon M12 resists most all media, including a broad range of lubricants, and has outstanding wear resistance and friction characteristics. The cost-effective material also provides extended seal life, as well as a wide operating window in temperature, pressure and velocity. “On almost every parameter it is better than previously recommended compounds—sometimes significantly—or was at least equal to them,” says Trelleborg Sealing Solutions’ Fort Wayne product manager Nancy Getz. Turcon M12 can fit hydraulic applications and meet a more universal range of applications.”

Trelleborg Sealing Solutions
http://www.trelleborg.com/

Seal material now rated for wider temperature range

The manufacturer of the sealing material Isolast J9440 says it has been improved with a higher operating temperature—up to +240°C —and it’s accredited to the USP Class 6 standard for use in medical and healthcare industries. Isolast J94440 has a continuous operating temperature range (from -7 to 240°C) and is compatible with most media. The material is part of the Isolast range of proprietary perfluoroelastomers from:

Trelleborg Sealing Solutions
www.tss.trelleborg.com/us

ISO fits and tolerances? There’s an app for that

An iPhone app, based on the ISO 286 System of Limits and Fits, “ISO Fits & Tolerances,” will help engineers cut time and let them work away from their desks for some tasks.

ISO Fits & Tolerances is easy to use. After entering a nominal diameter, select the tolerance classes for bore and shaft. The app then provides the complete ISO fits definition with all relevant values, including the type of fit. Tolerances are shown for the most commonly used ISO tolerance classes. Graphs illustrate these classes by bore and shaft.

“This is the first app from Trelleborg Sealing Solutions with several more in the works,” says Wolfgang Heinrich, Website Specialist.

The app includes one-touch access to Trelleborg’s library on YouTube. Users can also click ‘Contact’ to email or be connected to the company website. “ISO Fits & Tolerances” is available in English and German free from iTunes or via the Apple App Store on the iPhone and iPod Touch. Search “Trelleborg ISO Fits.”

Trelleborg Sealing Solutions

trelleborg.com

The story below the first full-scale floating wind turbine

The innovative offshore floating Hywind wind turbine, moored in the North Sea off the Norwegian coast, demonstrates how Trelleborg Offshore’s syntactic foam buoyes contributes to the future of offshore power generation. “People see the tower and turbine, but forget that the expertise in designing the subsea portion is also critical, because it keeps the whole turbine afloat,” says Gary Howland, the company’s Renewables Sales Manager. “The dynamic floating structure weighs 5,300 tons and measures 165-m tall. A full 65m floats above the sea surface. The 13 km power offtake and communications cabling attached to the structure further adds to its weight.

“This subsea technology is already proven. The Distributed Buoyancy Modules (DBMs) developed for deepwater support of umbilicals and risers in the oil and gas industry are ideal for this application becuause they help reduce project risk using proven technology.

“It’s like an iceberg; the mass floating below the surface ensures stability. Unless the weight is supported by properly designed buoyancy the whole structure would be much less able to resist the extremes of the offshore environment and the cable could suffer premature damage,” says Howland.

For Hywind, Trelleborg Offshore designed and supplied 45 polymer-coated syntactic foam DBMs which provide buoyancy support for a 3 ton, 100-m section of cable as it exits the turbine spar and descends to the sea bed at 220m below the surface. The buoyancy modules include an internal clamp for secure fastening and precise positioning on the cable.

“For best buoyancy under different sea conditions, engineers calculated the position of the buoyancy modules on the cable. The positions must be maintained, despite stresses during launch and in operation. The clamp is crucial. Its design, material selection, and manufacturing technique are critical ensuring the finished clamp maintains the buoyancy module position, during cable contraction and expansion, over the 20 year lifetime of the project.

“Trelleborg Offshore has substantial expertise operating in deep water and subsea environments, and a track record acknowledged by many offshore engineering companies. The company also has experience with DBMs and says more than 35,000 modules are in service.

“We have seen many of the technical challenges before, in the offshore oil & gas arena, so our engineers can quickly and easily adapt proven solutions for use in offshore wind-power generation. This will greatly reduce project risk and let industry develop quicker and at less cost.”

Tests show Trelleborg bearings wear exceptionally well at low velocities

Trelleborg Sealing Solutions’ Orkot^® TXMM bearing material has proven to be one of the best in direct electric motor propulsion systems on ships. The motors operate at low shaft velocities and, subject to boundary lubrication, bearings used must demonstrate exceptional wear resistance.

An extensive test program was conducted to prove Orkot^® TXMM bearing material performance at low velocities. Bearings were tested to extremes: velocities down to 5 meters/16 feet per minute at pressures up to 6 bar/87 psi and water flows down to 2 liters/4 pints per minute. The seawater contained Silica flour at 250 parts per million, and the 200 mm/8-inch bearing operated on an LG4 Bronze sleeve for 2,000 hours. The resulting overall wear of the bearing was just 0.027 mm/0.001 inch per 1,000 hours, and shaft wear was minimal with an improved shaft finish. The tests were repeated successfully with Inconel and Nickel Chrome Boron coated shafts.

“Orkot^® is a unique material. Resistant to seawater, it is proven in numerous marine applications,” says Marty Hugney, marine segment manager for Trelleborg Sealing Solutions Americas. “The bearings perform exceptionally in demanding low velocity situations. This translates into benefits for our customers. Orkot^® bearings have almost twice the bearing life of alternative products.”

Orkot^® Marine Bearings are manufactured from unique synthetic composite incorporating solid lubricants. Virtually no swelling in seawater and very low thermal coefficient of expansion provide dimensional stability in arctic and tropical seas. The bearings do not corrode or promote corrosion of the housing and tolerate both edge loading and misalignment.

A super seal for temperature extremes

Isolast J9876, a recent perfluoroelastomer, provides the most comprehensive media resistance at elevated temperatures of any perfluoroelastomer on the market, according to its developer. Seals in this material, from Trelleborg Sealing Solutions, extend their life in aggressive, high-temperature environments at an optimized cost-to-performance ratio. Equipment suppliers and process managers benefit from the advantages of a single material: reduced stocking, simplified procurement and prevention of early failure due to fitment of a seal in the incorrect compound.

“This new material represents the next generation of Isolast, our proprietary perfluoroelastomer,” says Muzaffer Sheikh, Isolast Product Manager. “Isolast provides a balance between outstanding thermal performance and compatibility to most all media. Its flexibility means equipment manufacturers and processors can select it for all their demanding sealing needs.”

Isolast J9876 has a continuous operating temperature range from +19 to +527F (-7 to 275C) with occasional peaks to 599F (315C). The material’s media resistance at high temperatures means excellent long-term physical property retention. The compound comes in any size O-ring, gasket, molded part, or rubber-to-metal bonded components, including door and gate seals.

Bearing handles rocking platforms

A heavy-duty flexible bearing or bushing combines a high-load capacity with an ability to accommodate torsional and angular movements in all planes without lubrication or metal-to-metal wear. The Spherilastik Bearings come in center bore or as a solid member depending on how it’s attached.

Typical uses include equipment in wind turbines, traction and braking reaction arms for rail, road, and off-road vehicles, hydraulic damper fixings. The bearing works well on wind turbines where high frequency vibrations must be isolated while accommodating high thrust forces. The rubber section is bonded to the spherical inner member and to the outer. When pressed into the bearing housing, the three segments preload the rubber in compression. Preloading increases its resistance to fatigue, thereby extending its working life.

Trelleborg Sealing Solutions
www.trelleborg.com/industrialavs

Teeter bearing help wind turbines Sssssssh

A few early wind turbines in the U.K. drew considerable criticism because they were noisy, So Wind Energy Group Ltd. (WEG) paid more attention to acoustic isolation in the recent MS-3 turbine. The primary noise-attenuation feature was a Metalastik Spherilastik “teeter” bearing from Trelleborg Industrial AVS. The bearing acts as a resilient spherical joint. In addition, the compact rubber and metal component also keeps noise and vibration to a minimum. Spherilastik bearings are intended for unlubricated, maintenance-free operation and are typically used in applications that call for a heavy duty yet compact bearing.

Two years later the company developed a more complex isolation system for another U.K. wind farm and the first a harbor. The Trelleborg suspension was installed in the three 300 kW turbines closest to the town two years after it opened to lower overall noise levels. The package consisted of four Spherilastik and several large Metalastik Cushyfloats for each of the three turbines. Measurements showed these mounts reducing structure-borne noise by 4 dBA.

Later, a technology exchange between WEG and the Kirloskar Electric Company of Bangalore, India, saw introduction of the first Trelleborg AVS rubber and metal bearings into wind farms on the sub-continent.

More recently, Trelleborg’s collaboration with Windflow Technology in Christchurch, N.Z., has the turbine manufacturer using the Spherilastik bearings for its New Zealand manufactured Windflow 500 turbines. The turbine features a two-blade rotor rather than the more conventional three. In addition to being lighter, and less expensive to manufacture and install, two blades let the rotor plane teeter, up to 6° on either side of the normal plane of rotation in response to varying wind forces. This is important because it reduces bending forces on the turbine shaft, gearbox, tower, and foundation. As a result, these elements can be lighter and less expensive than they are on a three-blade design.

The Trelleborg bearings are part of the pitch-teeter coupling mechanism in the hub. The two-bladed rotor, mounted on a hinge, teeters back and forth slightly as it rotates. The mechanical pitch coupling permits passive pitch movement and changes the natural frequency of teetering, away from resonance, so as to minimize teeter restraining loads.

Trelleborg’s Spherilastik bearings act as a resilient spherical joint, providing articulation and letting the rotor hinge mechanism pivot, while also suppressing noise and vibration. The first five production turbines have been performing well in an area with some of the strongest winds in the world.