Go Green with Graphalloy®

GRAPHALLOY^®: Finds Its Place In Renewable Energy


GRAPHALLOY bearings are helping to solve the world's energy needs. The advantages of alternate power sources are well-documented. However, because of the extreme nature of the environments required to generate power, it often becomes impossible to use traditional bearings. For years, Graphite Metallizing has been supplying products to companies involved in the production of clean, renewable energy. GRAPHALLOY has proven to be tough enough for these applications. Here are a few examples:


Tidal Power
Tidal power provides an inexhaustible source of renewable energy. A company in New England was seeking low maintenance bearings for a turbine shaft suspended forty feet below the ocean surface. As the tides move in and out, the turbines spin and generate power. GRAPHALLOY bearings proved ideal for this application because they operate successfully in submerged conditions and tolerate abrasive environments like salt water.


Geothermal Power
Geothermal power offers an unlimited source of non-polluting power. GRAPHALLOY provided a solution to the largest geothermal power field in the world by developing a special grade bearing for this severe service. After 25 years, GRAPHALLOY bearings continue to be a critical component of geothermal power generation.


Solar Power
Solar power has proven to be the "ultimate" in renewable energy. GRAPHALLOY bearings are being used in this high temperature application allowing panels to slowly follow the sun while generating high temperature steam.

Graphalloy finds a role in virtually every industry. When you have a tough bearing problem - Graphalloy has probably already found a solution. Call/ email their engineers. http://www.graphalloy.com/

How will Graphalloy handle our jet fuel pump application?

The principal bearing issue for Jet fuel is its very low specific gravity which makes jet fuel a poor lubricant.

Graphalloy bearings have many applications in very low gravity pumpages (lng, ethane, propane, benzene, CO2 etc.). Graphalloy is excellent for these applications because in these low specific gravity fluids Graphalloy provides a margin of safety allowing moving parts to contact without galling or seizing.

We have a history with aircraft fuel gear pumps (from memory I think these go back to the 60's). Our primarily pump business is in high HP centrifugal boiler feed and process pumps (vertical and horizontal) where low lubricity, flashing or run dry conditions are a possibility. Graphalloy bearings will allow the pump to survive an upset. So we have lots of related experience and are confident that the materials can handle a jet fuel pump but we encourage you to do you own testing in as close to real world environment as possible.

We mostly supply finished bearings/bushings and generally these are custom sized for a specific manufacturer's equipment. Pumps are a large part of our bushing applications. The key Graphalloy material advantage is the ability to run dry or in very light fluids (jet fuel for example) without galling. This permits the pump to run dry for a period and then re-establish pumping without failing. (FYI http://www.graphalloy.com/html/pump.html ).

For a metal pump, the usual design is to install, with a press fit, directly into the housing of the pump. The bushings can be supplied with a metal backing but this is normally not necessary. One advantage to the press fit installation directly into the housing of the pump is that as the temperature of the housing changes the bearing can be designed to maintain both secure mounting and a constant clearance to the shaft over a wide range of operating conditions.

In order to proceed to a design, our engineers will need: pump cross sections and dimensions on housing and shafts, materials of construction, rpm, expected loads and pumpages.

How does Graphalloy compare to Tungsten Carbide

A reader wrote to ask about the comparison of Tungsten Carbide to Graphalloy.

As you know Tungsten Carbide is an extremely hard, brittle material. As a bearing, it resists wear from abrasives.

Graphalloy is much softer, but can last longer running dry (without lubrication). However, it doesn't stand up to abrasives as well.

Which is better, depends on the application. Go to www.graphalloy.com/html/inquiry.html and give the engineering department a chance to review your application.