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.

Many seals for turbine tasks

There is a lot of sealing work in a nacelle. Hydraulic equipment, of course, needs them along with areas such as where blades meet hubs. These must all be weather tight yet allow rotation. Simrit Americas, Plymouth, Mich., manufacturers several designs in a range of materials for these applications. For instance:

Simmerring seals meet and exceed DIN 3760 standards for seal function and lifespan. Available in over 3,500 different dimensions, the seals protect motors and machines in original equipment and provide options for maintenance personnel. Designs in NBR and FKM materials are available especially for wind turbines. The seals can also be equipped with a leakage sensor.

Simmerring Radiamatic, a form-pressed continuous ring, works well on the large dimensions encountered in wind turbines in part due to rust-proof tension spring which presses permanently against the seal rim. The seal comes in 200 to 1,700-mm diameters.

Profile rings, large seal areas, are batch vulcanized for advantages over glued rings. Profile rings are available in standard materials, such as NBR, CR, and others. Profile rings ensure long working lives, low torques, high resistance, and security against press out. Profiles are well suited for sealing pivoting bearings.

Accumulators store hydraulic fluid at pressure for a constant, uninterrupted supply for hydraulic blade positioning and braking. To ensure such functions, Simmerring accumulators are adapted to individual applications. Users also benefit from lower costs of smaller pumps.

Vibrations in wind power plants cause increased wear on equipment and noise. The company offers a large selection of conical mounts, ultra bushes, layered springs, circular mounts, Mo-mounts and V-mounts for wind applications. Conical mounts work on generators in wind turbines with high damping effect on vertical vibrations, while absorbing vertical forces and insulating structure-borne noise.

Adhesives, sealants, and more for wind-turbine manufacturing

To support growth in the wind energy market, Henkel Corp., Rocky Hill, Conn., has developed a range of products for manufacturing and maintaining wind turbines. These include structural adhesives, mold-release agents, machinery adhesives, sealants, grouts, cleaners, surface treatments, tapes, and metalworking materials. Company wind-turbine products, such as Loctite, Teroson, Bonderite, Frekote, Multan, and P3, are used for blade and nacelle manufacturing, tower assembly, hub, bearing and gearbox assembly, field installation, and maintenance.

The company formulated the first Germanischer Lloyd-certified two-component structural polyurethane adhesive, as well as MMA adhesives for blade bonding and repair. These adhesives cure at room temperature and provide crack-resistant, long-lasting bonds on composites and metals. Loctite machinery adhesives such as threadlockers, thread sealants, retaining compounds, and gasketing materials, prevent fasteners from loosening, seal pipes and flanges, and bond cylindrical components. Applications include blades, gearboxes, hubs, brakes, and pitch and yaw bearings.

In addition, says the company, butyl tapes and sealants are used to vacuum form composite laminates, while Frekote, semi-permanent mold release agents, are used when molding large-scale composite components such as blades and nacelles. For waterproofing blades, nacelles and towers, and general turbine maintenance, Henkel sealants offer flexibility, primerless adhesion, short cure periods, and temperature resistance. For tower installation, Loctite high-strength grouts withstand high-torque loading and are available in grades for deep pours.

Furthermore, says Henkel, its Multan and P3 metalworking products are used during machining, forging and general forming processes and for short-term corrosion protection. Bonderite and Alodine metal surface pretreatment materials protect towers, hubs, and gearbox components from corrosion. Henkel cleaners are environmentally responsible formulations for cleaning during manufacturing and on-site maintenance of blades, nacelles, and towers.