GRAPHALLOY Provides Advantages in Pump Bushings and Wear Rings

GRAPHALLOY^®, a graphite/metal alloy, is used extensively for pump bushings and wear rings.  It offers two key advantages for pumping applications:

1. GRAPHALLOY enables pumps that run dry, flash, or handle extremely low viscosity fluids to survive without damage.  Numerous case histories and pump manufacturer test results confirm that GRAPHALLOY performs where plastics are unable to stand up and metal parts seize disastrously.

2. GRAPHALLOY enables rings and bushings to be designed with tighter clearances which can improve efficiency, increase output, reduce vibration, throttle seal cavities, or act as a seal backup.  GRAPHALLOY is non galling and dimensionally stable and enables pumps to operate at tight fits without the risk of metal-on-metal rubs or seizure.

Click here to learn more about the use of GRAPHALLOY in pumping applications.

Fitted Pumps Successfully Run Dry with GRAPHALLOY

GRAPHALLOY® self-lubricating wear parts keep pumps from seizing during dry-run, low-flow, start-up, slow roll and shutdown. These are conditions that cause metal to metal pumps or plastic wear parts to fail, sometimes catastrophically.

How Difficult Can Pumping Water Be?

A paper mill in the Pacific Northwest was experiencing failures with the operation of three identical boiler feed pumps (two motor driven and one steam-turbine driven). The pumps were 6-stage horizontal split, opposed impeller, channel ring diffuser design. Multistage split-case pumps of this design are susceptible to deflection and vibration during start-up, coast down and upsets.

These pumps were operating in 260 degrees F (125 degrees C) boiler feedwater at 3560 RPM. With the instrumentation available, the operators had a difficult time determining where the pumps were operating on the performance curve.

While attempting to bring the steam turbine driven pump online, the pump was run at zero flow until it seized. Because of a history of failures, the OEM repair center recommended that the pumps be refit with GRAPHALLOY stationary wear parts.

Engineers at Graphite Metallizing Corporation designed a retrofit solution modifying the existing metal wear parts to accept GRAPHALLOY inserts. The case wear rings, diaphragm bushing and intermediate cover bushings were all modified to include Nickel GRAPHALLOY wear parts.

Failure Averted

Soon after this conversion, the pump experienced another incident. A minimum by-pass line was plugged and, as a result, the pump operated at no flow until the users were able to discover the plugged line (located two floors above the pumps).

The non-galling, GRAPHALLOY fitted pump not only survived but continued in service. Metal or plastic wear rings would have almost certainly caused a failure. The upgrade to Nickel GRAPHALLOY stationary wear parts allowed these pumps to operate under severely adverse conditions that could cause plastics to melt and metals to seize.

The GRAPHALLOY retrofit provided this paper mill with increased efficiency and reduced downtime.

Consider the advantages of GRAPHALLOY for your next pump application:

• Self-lubricating
• Non-galling
• Engineered for your specific application
• Operates in temperatures from -400 degrees F to +1000 degrees F/-240 degrees C to 535 degrees C

GRAPHLON GM 860® — An Abrasion-Resistant Pump Bushing Material

GRAPHLON GM 860® is an abrasion-resistant bushing material that protects pumps and helps prolong pump life. Developed by Graphite Metallizing, the material is a tough, polymer/graphite-based alloy used in the manufacture of pump bushings and other critical-wear parts.

GRAPHLON GM 860® provides exceptional abrasion resistance in harsh environments, has high compressive strength and can handle temperature extremes from -100˚ F to 300˚ F  (-75˚ C to 150˚ C). It is inert to most noxious chemicals, including acid mine water, hydrogen sulfide and jet fuel, and does not swell in water.

GRAPHLON GM 860® was developed as a replacement for traditional pump materials which are prone to damage from highly-abrasive suspensions. River water pumping stations and down hole sump pumps are two examples of key applications. The material also performs exceptionally well under both dry running and severe-duty abrasive-contaminated conditions.

Graphite Metallizing Corp., established in 1913, produces GRAPHALLOY® a graphite/metal alloy bearing material used in the manufacture of self-lubricating bearings and components for machinery and process systems.

GRAPHALLOY® Bushings For Clean Geothermal Energy

GRAPHALLOY® Bushings Keep Geothermal Brine Pumps Pumping


GRAPHALLOY bushings were made to conquer harsh environments. And what test could be tougher than a brine pump at a geothermal power plant?

Geothermal power is an important source of renewable energy because it is cost effective, reliable, sustainable and environmentally friendly. One U.S. power plant - a large commercial producer of geothermal energy - was experiencing major problems with its geothermal brine pumps. Geothermal brine is highly corrosive and was causing the 416SS Boron coated bearings to fail and, as a result, service life was severely reduced.

The pumps are Johnston Pump Model 24.5 x 8 x 10 Type JTCF (Discharge Head and nine stages of Type 12ES Bowls) with the following service conditions:

Flow: 1300 GPM
Total Developed Head: 485 feet
Temperature: 350° F - 400° F/180° C - 200° C
Specific Gravity: 0.89 SG

The maintenance staff at the plant tried several other bearing materials, including bronze and a type of PEEK plastic. Neither provided acceptable performance.

In 2008, the staff converted one of the brine pumps to Nickel GRAPHALLOY because they knew of its resistance to corrosion and its non-galling properties.

Results have exceeded expectations. In fact, the Maintenance Staff recently converted two additional brine pumps to Nickel GRAPHALLOY.

GRAPHALLOY bearings have been improving the operation of pumps in difficult applications for almost a century. Graphite Metallizing, makers of GRAPHALLOY, has been supplying products to companies involved in the production of clean, renewable energy for many years. Because of the extreme nature of the environments required to generate geothermal power, the use of traditional bearings often proves difficult. Yet GRAPHALLOY is tough enough for these applications.

Is GRAPHALLOY a good fit for your pump application? Our engineers can walk you through the key advantages of these bearings and discuss the right GRAPHALLOY solution for you.

GRAPHALLOY® Introduces NSF® Certified Grades For Pumps

Used in Pump Bushings and Bearings for Vertical and Horizontal Pumps

Graphite Metallizing Corporation, the manufacturer of self-lubricating GRAPHALLOY® bushing materials, is pleased to announce that NSF® International, has just certified two grades of GRAPHALLOY material for use in municipal well pumps and water treatment plant applications.

The two newly certified GRAPHALLOY Grades are certified to NSF/ANSI Standard 61 - “Drinking Water System Components/Health Effects” - and approved in the category for Multiple Water Contact Materials (MLTPL) up to 180˚F.

NSF certification is the result of Graphite Metallizing’s rigorous product testing to ensure the highest quality GRAPHALLOY products for the market. These newly certified grades are used in the manufacture of pump bushings and bearings for both vertical and horizontal pumps.

GRAPHALLOY is currently the product of choice for many deep well water pump applications in the western U.S., Hawaii and around the world.

NSF International is the independent, not-for-profit/non-governmental organization that provides materials evaluation, standards testing and product certification services involving public health and safety issues.

Graphite Metallizing Corporation, a global leader in the manufacture of self-lubricating bushings and bearings for almost a century, produces GRAPHALLOY, a graphite/metal alloy bearing material used in the manufacture of self-lubricating bearings and components for pumps, machinery, and process systems.

Chemical Plant Experiences Bushing Failure in Gear Pumps

The Competition Said "No" but GRAPHALLOY^® Said "Yes"

A chemical plant in Tennessee was experiencing rapid bushing failure in their gear pumps. These bushings were failing after only a few weeks of operation.

When plant representatives contacted this carbon bushing manufacturer about the problem, they were told that there was "no solution". The bushing manufacturer - our competitor - claimed that the viscosity of the polymer being pumped was simply too thick.

Unhappy with this response, the chemical plant engineers contacted Graphite Metallizing for assistance. After studying the problem, our engineers promptly responded by saying "yes, we can help" and that GRAPHALLOY bushings were the solution.

The pump that was failing was a positive displacement, herringbone-type gear pump with internal bushings lubricated by the pumped liquid. The pumpage is a polymer with heavy viscosity (150 -10,000 CPS) similar to a thick latex paint. The temperature can range from 80 degrees to 140 degrees F with a speed of 520 -1,750 RPMs and a load of 155 - 1,980 pounds. This pump has very high bushing loads because of the meshing gear forces. The calculated PV values were up to 500,000 - over four times the maximum recommended level for GRAPHALLOY in submerged services.

The GRAPHALLOY engineers provided a solution designed for applications involving the transfer of viscous liquids. Grade GM 119.3 bushings were recommended because of their load-bearing and corrosion-resistant capabilities. GRAPHALLOY engineers also recommended slight design changes to improve reliability.

The initial order was shipped to the customer and immediately installed.

The pumps fitted with GRAPHALLOY bushings have been operating for over one year without failure...six times the life of the competitor's bushings.

The success of these GRAPHALLOY bearings demonstrates the potential for GRAPHALLOY upgrades in chemical plants. If you have a pump that may benefit from GRAPHALLOY, please contact us with details about your application.