GRAPHALLOY Bushings and Bearings

Search This Blog

Tuesday, December 11, 2012

GRAPHALLOY Bearings are FDA Accepted

GRAPHALLOY® bearings are key ingredients for minimal maintenance and uninterrupted production in food contact equipment. The FDA has accepted GRAPHALLOY, a graphite/metal alloy, for use in ovens, conveyors, pumps and mixers.

  • Self-lubricating; works without external lubrication
  • Operate in extreme temperatures (-450° F to +750° F/-240° C to +400° C)
  • Avoid loss of lubricant in steam/pressure washes
  • Contain no oil or grease
  • Can be immersed in liquids without contaminating food production
  • Operate submerged in low viscosity and corrosive liquids

High heat applications challenge the life and durability of conventional bearings. In cold, wet environments, bearings often cannot hold lubrication. Use of GRAPHALLOY bearings can solve these problems and, as a result, reduce downtime and lost production.

For more information about the success of GRAPHALLOY in food applications, please read our Pizza Oven Case History and our Seafood Processing Plant Case History.

Monday, November 19, 2012

GRAPHALLOY Replaces Ball Bearings In High Temperature Application

GRAPHALLOY® self-lubricating bearings keep the wheels rolling for a manufacturer of specialty powders

When a major manufacturer of alumina powders contacted us because of a high rate of sealed ball bearing failures in their oven carts, we knew GRAPHALLOY bearings would solve the problem.

Sudden stops ruin equipment and material
Our customer manufactures high purity alumina powders and specialty powders designed for a wide range of markets including lighting, watches & jewelry, health & medicine, plasma TV and microelectronics. The manufacturing process for the powders consists of loading pans of  powder mixture onto a train of carts which are then driven by an electric motor through a series of ovens. Each cart has four casters, with bushings, that ride on rails into the ovens. It is critical that the carts move through the heating process in a smooth manner, at a constant speed so that the blocks of powder do not break.

The sealed ball bearings on the carts were losing lubrication and sticking due to the high oven temperatures. This was causing the wheels to lock and the carts to come to a sudden stop. The electric motor would continue trying to drag the carts through the oven.  As a result, the powder blocks would break and the cart wheels developed flat spots from sliding rather than spinning.  Since the carts would not move freely, the electric motor would overload and fail.  The carts would then have to be manually pulled through the ovens.

Greaseless GRAPHALLOY Solution
Our engineers reviewed the application and recommended one of our self-lubricating GRAPHALLOY grades to replace the sealed ball bearings. Our customer tested the GRAPHALLOY bearings on two carts. During the test, the customer told us they randomly pushed carts by hand and only two carts moved smoothly when pushed: the carts with the GRAPHALLOY bearings installed. Since the customer changed all his cart bearings to GRAPHALLOY, he estimates saving thousands of dollars annually in replacement parts, maintenance costs, product waste and downtime.

Consider the advantages of GRAPHALLOY for your next application:
- Self-lubricating
- Temperature extremes
  (-400° F to +1000° F/-240° C to 535° C)
- Extended operation
- No downtime

Thursday, October 25, 2012

High Temperature Damper Solutions

A power company in North Carolina was having problems with their ID fan dampers between the electrostatic precipitator and the stack.  The high temperature for the flue gas (approximately 300° F) coming out of the precipitator was baking the grease in the bearing. 

This gas contained some fly ash that was causing clutch failures in the damper actuation system and required emergency maintenance to avoid shut down of the boiler. GRAPHALLOY® 845 inserts were installed to replace the ball bearings. 

The dampers have run trouble free for more than two years.

Monday, October 8, 2012

GRAPHALLOY Solves Problems in High Temperature Steel Mill Cooling Bed

A Midwestern steel mill was using GRAPHALLOY® bushings for the horizontal rollers in their cooling beds. The bushings were thriving under severe heat and water spray conditions. 

Because of this success, the mill was considering using GRAPHALLOY flange bearings for another application: the vertical guide rollers along the sides of the cooling beds that were used to keep the hot steel from running off the sides. 

These guide rollers remain static until a piece of hot steel slams up against them. At this moment, they are expected to turn instantly to guide the steel back onto the cooling bed. This mill had been using conventional greased rolling element bearings in the vertical guides that were lasting only a few months. GRAPHALLOY proved to be successful on the vertical rollers as well and the mill has since retro-fitted additional lines with GRAPHALLOY.

Wednesday, September 19, 2012

GRAPHALLOY at the Houston Pump Symposium

Graphite Metallizing Corporation, manufacturer of GRAPHALLOY® bearings and bushings, will be exhibiting at the 28th Annual Pump Users Symposium in Houston, TX. This symposium will be held at the George R. Brown Convention Center from Monday, September 24 through Thursday, September 27.  

Engineers from Graphite Metallizing will be available to discuss the success of GRAPHALLOY, a graphite/metal alloy, in difficult pump applications. 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.

GRAPHALLOY® wear rings and bushings operate at longer intervals without the need for replacements or maintenance which helps reduce downtime and maintenance expenses. In addition, GRAPHALLOY® operates successfully in temperatures from -400°F to +1000°F (-240°C to 535°C).

If you have an application where service and maintenance tasks are cumbersome or difficult to perform, speak with a GRAPHALLOY® representative at Booth #1715.

Monday, September 10, 2012

GRAPHALLOY® Self-Lubricating Bushings Will Not Seize

The environment in a rubber curing autoclave is 300ºF (150ºC) and has live high pressure steam. The grease-lubricated roller bearings were failing due to high heat and moisture,  causing interruptions in production. When a bearing failed, production was stopped due to the short shelf life of uncured rubber. 

GRAPHALLOY® bushings were installed and, after more than one year, there has been no production interruptions. If replacement is necessary, it can be done during scheduled outages because self-lubricating GRAPHALLOY will not seize the shaft.

Monday, August 27, 2012

Solutions With GRAPHALLOY® 4-Bolt Flange Inserts

High temperatures were causing premature failures of 4-bolt flange bearings in this glass manufacturer’s lehr. Bearings had to be heavily greased in an attempt to keep them running.

Unfortunately, the excessive use of grease was causing a safety and fire hazard. Chronic failures were still occurring, resulting in frequent down time and lost production.

An economical solution was found by retro-fitting the existing housings with GRAPHALLOY® 845 Series Inserts. The inserts have now lasted more than a year without a single failure or need for replacement. Using GRAPHALLOY 4-Bolt Flange Inserts has saved this company over $150,000 to date.

Wednesday, August 8, 2012

Bearing Problems in Overhead Conveyors

A heat treat company was experiencing bearing problems with their overhead conveyor. They had high maintenance costs and lost production due to weekly bearing lubrication. Ball bearings, brass and bronze bearings were tried with no success.

GRAPHALLOY® Bushings and Thrust Washers were installed, generating annual savings of more than $15,000 in weekly maintenance costs alone.

Thursday, July 26, 2012

845 Inserts Solve Problem at Paper Mill

GRAPHALLOY 845 Inserts
GRAPHALLOY® 845 inserts solved a major problem at a paper mill in South Carolina.  The mill was experiencing production loss due to problems in their forced air dryers.  The dryers were used on a tissue paper line; rapid drying of the delicate paper was essential to the manufacturing process. The 650° F operating temperature in the drying process was causing bearing failures in the roof top damper banks. The result was production down time.

The ball bearings were replaced by GRAPHALLOY inserts.  After only six months operation, the customer was so satisfied that they replaced the ball bearings with GRAPHALLOY inserts on their second production line.

Monday, July 16, 2012

GRAPHALLOY® Extends Bearing Life in Paint Drying Oven

A paint drying oven at a brake shoe manufacturer was experiencing two months life from their roller bearings after being exposed to temperatures of 390ºF (200ºC). In spite of the water cooling system in the rollers, the bearing lubrication was failing and causing roller seizure and extensive maintenance costs.  

Self lubricating GRAPHALLOY® 845 Series Pillow Blocks were installed, eliminating the need for constant lubrication and the need for the water cooling systems. The 845 Pillow Blocks have run for more than a year with no apparent wear. GRAPHALLOY provided a significant improvement in the life of the bearings.

Tuesday, July 3, 2012

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

Tuesday, June 26, 2012

GRAPHALLOY® Bearings Cook Up Savings in Heat Treat Ovens

A spring manufacturer was experiencing problems in their heat treat oven. The bearings in an overhead conveyor required weekly lubrication as well as replacement three times a year.  Self lubricating GRAPHALLOY® bushings were installed eliminating the weekly lubrication and the expensive down time.

The spring manufacturer estimates cost savings of approximately $14,000 in lubrication alone. Additional savings were generated by the elimination of the shut down time.

Tuesday, May 29, 2012

High Temperature Damper Solutions

High temperature dampers can be a maintenance problem. These dampers experience temperatures that require frequent greasing and are often in places that are hard to re-grease. In addition, long periods of inactivity is another source of problems as grease hardens or vibration causes metal on metal galling.

Typical GRAPHALLOY Damper Applications:

  • Louver Dampers
  • Wind Boxes
  • Butterfly Dampers
  • Guillotine Dampers
  • Diverter Dampers
  • Radial Vane Dampers
GRAPHALLOY® is available in a variety of mounting styles from two and four bolt pillow blocks to two and four bolt flange units. These units are available as solid or split and also come with self aligning features.

GRAPHALLOY provides these "install and forget" features:

  • Temperature range from -400° F to +1000° F
  • Self Lubricating, requires no oil or grease
  • Will not seize or lock up
  • Self Aligning capabilities for proper alignment
  • Long life, maintenance free operation
  • Dimensionally interchangeable with most standard ball bearing units

Tuesday, May 15, 2012

Bushings that Outperform Metal Wear Parts in CO2 Service

Graphite Metallizing Corporation announces GRAPHALLOY® wear rings and bushings that provide performance superior to standard metal stationary and rotating wear part in pumps for CO2 service in oil field applications. Self-lubricating GRAPHALLOY, a graphite/metal alloy, eliminates concern about bearing failures or possible flashing of CO2

The ability to operate without additional lubrication is important in CO2 injection applications because CO2 has low lubricity. Standard metal wear parts rely on the lubricity of the liquid being pumped for proper operation so they are prone to failures in pumps used to inject CO2. In addition, due to high suction pressure required to keep CO2 as a dense phase liquid, flashing is always a possibility.

CO2 injection in older, low flowing wells is becoming an increasingly popular method for permeating rock formations and forcing more oil to the surface. Many older wells still contain vast amounts of oil locked in the pores of rock layers deep underground. CO2 injection often releases more oil in older wells than can be released by water injection. 

“Use of self-lubricating, non-galling GRAPHALLOY materials in pumps for CO2 service provides substantial cost savings by avoiding expensive downtime and field repairs caused by wear part failures,” said Eben Walker, General Manager of Graphite Metallizing Corporation. “GRAPHALLOY is currently the material of choice for many oil field applications in North America and around the world.”

GRAPHALLOY wear rings and bushings operate at longer intervals without the need for replacements or maintenance which helps reduce downtime and maintenance expenses. GRAPHALLOY is an excellent choice for any application where service and maintenance tasks are cumbersome or difficult to perform. GRAPHALLOY is a proven solution for even the most challenging plant maintenance and new equipment design applications.

Wednesday, April 11, 2012

GRAPHALLOY® Solves Power Plant Damper Failure

Pre-heated secondary air makes the inlet-air section of a utility boiler hot...hotter, in fact, than most steel bearings can handle.

A power plant had difficulty operating the dampers that control the flow of preheated air into the combustors. The hot air quickly dried out the lubricant in the steel damper bearings, causing the dampers to seize.

The problem was solved by replacing the steel bearings with self-lubricating GRAPHALLOY® bearings. These new bearings have been in operation for years without a single failure.

Failing Dampers Hurt Productivity
Secondary air accounts for 85% of the total combustion airflow to the cyclone burners. This air is heated to 650°F - 750° F (350° C - 400° C) by flue gas through a large heat exchanger. It then flows through a windbox duct to the cyclone burners where it is mixed with powdered coal. Airflow to each burner is determined by an 8’ by 6” by 2’ control damper. The dampers are not moved often and the grease quickly carbonized, locking the bearings.

The utility did not want to bring the unit offline for a bearing problem so it tried to make do. The plant was often forced to alter its firing methods.Frequently, the cyclone burners worked inefficiently due to the inability to control the combustion air. In some cases, it was necessary to fabricate a device to forcefully move a damper manually because operators could not budge them.

The Solution
The power plant solved the problem by replacing the lubricated steel bearings with self-lubricating GRAPHALLOY bearings. Of the 40 bearings used in the plant, 30 consist of three sizes of pillow block bearings while the other 10 are four-bolt flange block bearings.

The upgrade was accomplished during a planned outage. Initially, all of the bearings in one boiler unit were replaced. The GRAPHALLOY bearings ran without any problems and, one year later, the plant replaced the bearings in the other boiler.

The Benefits
The power plant experienced the following benefits by switching to GRAPHALLOY

  • The cyclone burners now operate more efficiently because the plant can precisely control the flow.
  • Operators are now freed from the time-consuming and distracting task of manually 
  • The plant has also had a substantial savings in costs for replacement bearings and labor.

Are you experiencing similar problems with heat and bearing failure? If so, the engineers at GRAPHALLOY will work with you to develop the right solution and help you beat the heat.

Monday, March 26, 2012

GRAPHALLOY® Electrical Solutions

GRAPHALLOY® Brushes, Slip Rings and Contacts solve signal applications where low noise is a requirement. They are available in various sizes and grades including copper, bronze and silver.

GRAPHALLOY Brushes are common in rotating equipment to conduct currents ranging from minute instrument or signal values to power ratings. Brush materials include Silver Graphalloy and Copper Graphalloy. Special high altitude grades are available as well.

These brushes can be used in:
•Microwave equipment
•Servo systems
•Thermocouple and strain gauge circuits
•Pulse systems
•Computer grounding contacts
•Torque indicators
•Medical equipment
•Packaging machinery

GRAPHALLOY Contacts are particularly valuable for interrupting highly inductive or heavy overloaded currents in circuit breakers, controllers, contactors and relays.

Possible Applications:
•Circut breakers
•Furnace Controls
•Medical apparatus
•Oven controls
•Welding Machines

Tuesday, March 6, 2012

GRAPHALLOY® Solves a Proton Beam Problem

The Fermi National Accelerator Laboratory (Fermilab) is a Department of Energy atomic particle research lab in Batavia, IL. Fermilab specializes in high energy physics research and devotes much of their efforts toward understanding the basic properties of fundamental particles including neutrinos and other subatomic particles.

Fermilab turned to GRAPHALLOY® bearings from Graphite Metallizing Corporation to solve a problem in a critical "neutrino target adjustment" mechanism when previous solutions had failed.

Fermilab's MINOS (Main Injector Neutrino Oscillation Search) is designed to observe neutrino beam composition and energy distribution as it travels underground from Fermilab in Illinois to the Soudan Iron Mine in Minnesota. Neutrinos produced by the particle accelerator at Fermilab are "beamed" 450 miles through the earth.

To produce this beam of neutrinos, a proton beam starts at the Main Injector accelerator. The protons are magnetically focused onto a target. Once the protons strike the target, secondary particles are produced, focused by a pair of magnetic focusing "horns". The particles of interest then decay into neutrinos. It is the mechanical adjustment of these focusing horns that requires GRAPHALLOY bearings.

This operation runs in a particularly hostile environment. It is radioactive and corrosive and is exposed to nitric acid and ionized air. Metallic bushings cannot be used. In addition, polymers, organics, plastics and oil cannot be used in the operation. Finally, the bearings must run dry.

The unique properties of GRAPHALLOY provided the solution to this application. GRAPHALLOY bushings were used to target and position the horns because other materials would corrode and freeze up...and continue to outlast the other materials in this target assembly.

(Image courtesy of Fermilab Visual Media Services)

Thursday, February 16, 2012

GRAPHALLOY for Bakery Applications

High temperature GRAPHALLOY® bushings have been the choice of oven manufacturers for many years. GRAPHALLOY bushings extend bearing life and reduce maintenance costs for bakeries in temperatures reaching 1000° F (535° C). GRAPHALLOY may be the answer to the most difficult operating problems.

The Food and Drug Administration (FDA) has accepted GRAPHALLOY for "repeat use in food contact equipment" in bakery ovens, pumps, mixers and conveyors. Ovens and conveyors, in particular, undergo high heat and continuous operation that challenge the life and durability of critical components. Self lubricating GRAPHALLOY bushings and bearings perform in temperature extremes...when conventional materials fail.

GRAPHALLOY, a graphite/metal alloy, prevents unnecessary downtime and lost production. It also survives wash down conditions common in many food applications. With its low coefficient of friction and high strength, GRAPHALLOY bearings deliver long life and are not subject to seizures binding or sudden failure. In addition, the high temperature, self lubricating capabilities of GRAPHALLOY bushings reduce maintenance costs

Thursday, February 2, 2012

GRAPHALLOY® Provides Help With Bearing Maintenance Problems

Need help with your bearing maintenance problems?
GRAPHALLOY® - a unique graphite/metal alloy commonly used as a bearing material - may be the solution. Self-lubricating GRAPHALLOY has provided solutions in pumps, dampers, turbines, valves and other process equipment.

What can GRAPHALLOY bushings do for you?
Deliver simple solutions for your design and maintenance problems;

◦Self-lubricating; requires no grease or oil
◦Low maintenance: install & forget
◦Non-galling; no metal to metal seizure
◦Stable; does not melt or cold flow or swell when submerged
◦Operates in temperature extremes: -450° F to +1000° F (-240° F to +535° F)
◦Low, constant coefficient of friction
◦Dry; does not collect dust or contaminants
◦FDA accepted grades available

Thursday, January 12, 2012

GRAPHALLOY® Turns Lead-Free Into Problem-Free

In an effort to address environmental concerns, a manufacturer of fluorescent lighting tubes initiated a program to remove lead from the glass. When this move to lead-free glass caused manufacturing problems,GRAPHALLOY® came to the rescue.

Lead was beneficial to the production process. The move to lead-free glass caused a problem with the bushings in the machine that flared the end of the tube and prepared it to attach and seal to the end plugs.

The lead in the glass had provided additional lubrication and kept the units from “gumming up” and sticking. With lead-free glass, the maintenance crew went from rebuilding the units once a year to once every three months.

The plant engineer contacted GRAPHALLOY engineers who then designed copper-grade self-lubricating GRAPHALLOY bushings to test in the machine. The GRAPHALLOY bushings were installed and the machine ran for three months with no problems. At that time, the plant placed a production order for an additional 200 pieces.

The machine fitted with GRAPHALLOY bushings has been operating for over one year without failure...four times the life of the original bushings.

The success of these GRAPHALLOY high temperature bushings provided this plant with better performance and significant cost savings. It demonstrates the potential for GRAPHALLOY upgrades in other manufacturing applications.

Tuesday, January 3, 2012

GRAPHALLOY® Attending International Exhibition in 2012

SEPEM Industries
Practical solutions on operation, maintenance and development to energy, chemicals, wood and furniture, metallurgy, plastics, rubber and various other sectors. For more information about this conference, please click here.

January 31, 2012 - February 2, 2012
Avignon Sud Parc des expositions
Avignon, France