These imperfections can be as random as inclusions, variations in grain structure or residual stresses, or all of the above.

The most severe of these imperfections are seen as residual stresses. These stresses can be visibly evident as dimensional changes (non parallel surfaces, or out of round) that are seen before the rotor or drum is put in service and then those stresses become relived during operation and cause premature brake failure as a result of brake warp, or these stresses remain unseen and only become evident after the vehicle is put into service.

However these imperfections can be seen as a dimensional signature when conducting tensile testing (see figure 1).

Figure 1 shows the wide disparity in tensile strength in 5 samples from the same brake rotor. In practice the lower tensile strengths will in all probability show up as warping during operation. As the shoe or pad make contact with the rotor or drum the heat created and/the shock of hitting a puddle with a heated brake will cause the brake to distort (warp) at the point of stress.

The patented Thermal Balance Brakes Process, Thermal Cycling, realigns the structure of the metal at the molecular level and relieves the residual stresses, realigns the grain structure, and reduces the vibration, which in turn reduces metallic fatigue. These changes result in a three to five times increase in the functional life of a rotor or drum.

Figure 2 shows the tensile test results from same brake components after the Thermal Balance process. Note, first the uniformity of the tensile strength and also the increase in overall strength.

Figure 1 Figure 2
42,500 42,100
41,300 42,100
39,500 42,500
43,100 42,100
42,600 42,500

VSM probably got its start, in its most crude form, with mechanics. Mechanics would bang on a machine with their wrench, listen for the sound to echo back, and pronounce that the machine was defective and needed replacing. Auto mechanics still use a simple medical-type stethoscope to detect and diagnose sounds generated by car engines. VSM has come a long way since then, with far more sophisticated tools that offer automated features and capabilities.

Until recently, VSM required fleet maintenance operators to have a healthy understanding of vibration analysis to use the tools effectively. Analysis was manual; an operator was required to dial a vibration instrument across its full frequency spectrum in order to identify frequencies at which the vibration was prominent. The operator would then compare peak frequencies and manually consult a chart for probable causes. With continued inspection, the operator was eventually able to detect some potential equipment malfunction.

The latest generation of VSM has automated the manual requirement. No longer is PdM dependent upon individual operators who are highly skilled at reading vibration printouts. Today an Impact Hammer and associated software can provide detailed snapshots of exactly what is going on with a brake, pinpointing the exact problem before a catastrophic event occurs.

Underlying premise of Vibrational Signature Monitoring….Metal Fatigues

VSM is founded on the premise that metal “fatigues.” All metal parts are built with a specific design in mind, to be able to deal with a given load or “stress”. Continuous use of a part, even as designed, eventually results in the metal wearing away or corroding. This is especially true when the brake is exposed to adverse environmental conditions (such as high speed driving or stop and go driving). At the point that the brake’s metal begins to corrode, it is no longer able to do the job for which it was originally intended. This is “Metal Fatigue”. The purpose of VSM is to measure the degree of fatigue without having to actually remove the brake from service.

Each brake has a naturally correct vibrational signature, much like a tuning fork. Strike a tuning fork on a table. It vibrates and produces a sound, or “Signature”. Each brake, just like a tuning fork, has a unique signature it produces when struck. The signature is observable on an oscilloscope as frequency and amplitude. VSM records the brake’s signature while the brake is in good working order and establishes an acceptable range of frequencies for the brake to be considered functioning normally. Any subsequent measurements recorded are compared with the acceptable range.

As brakes fatigue, their unique vibration spectra changes. Continuously recording signatures enables fleet operators to monitor the brakes off hours watching for major spectra changes. In this way, even hairline fractures can have early detection. When the brake’s spectra change beyond the acceptable range, fleet operators are alerted that those brakes require manual inspection or replacement.

Vibrational Signature Monitoring with Thermal Balance Brakes

The key to VSM success is Data Collection and Data Synthesis. Continuous data collection and synthesis of brakes provides a direct correlation between the brake’s mechanical condition and the recorded acceptable range.

Data Synthesis

Using an impact hammer with built in SmartSensors, Thermal Balance Brakes can now provide fleet operators a vibration signature monitoring procedure for brakes that are still on the vehicle and in service. SmartSensors inside the impact hammer actually synthesize the data collected thereby determining the brake’s condition.

Thermal Balance Brake’s Custom Software

Thermal Balance Brakes does not just provide SmartSensors. They also provide custom software as well, tailored to the needs of the fleet maintenance operators. Impact hammers transmit vibrations to the custom software for analysis by tapping the brake with the hammer while the brake is still on the vehicle. The software receives the new vibration and compares it to previously recorded vibrations., looking for any vibrations outside the acceptable range for the fleet operators to manually inspect.

During the Thermal Cycling process, brakes are alternately cooled and (sometimes) heated until they experience molecular reorganization. This reorganization “tightens” or optimizes the particulate structure of the brake throughout, relieving stresses, and making it more dense and uniform (thereby minimizing flaws or imperfections). The tighter structure also enhances the energy conductivity and heat distribution characteristics of the brake. It minimizes “hotspots”, enhances cooling, and impedes the ability and tendency of brakes to vibrate; significantly reducing that as a factor in fatigue and eventual failure or cracking. Corrosion resistance is also enhanced. Being more uniform, the brake is able to retard the forces of oxidation and chemical degradation.

Ancillary processes like plating, bonding and brazing adhere better when applied to be brake before thermal cycling. The result is greater strength, resilience and durability, all combining to produce substantially improved performance and wear. As the process is based primarily on temperature modulation, it is efficient, clean, non-polluting, and does not alter the appearance or dimensions (measurably) of the brake. And, because it is not a coating, it cannot be unevenly applied, nor can it wear off.

Thermal Balance Brakes has been the leader in developing Thermal Cycling for a long time. A thermal cycled brake will have a longer life expectancy by as much as 200%.

Once the metallic brake is Thermal Cycled, the brake tends to be under less stress. The brake stops truer and faster, providing a significant savings to municipalities, truck and airplane maintenance operators etc.

Thermal Balance Brakes now guarantees in writing a 50% cost savings for Thermal Cycled brake drums and rotors.

As expected, a brake will wear until its performance is eventually compromised. With repeated application, the brake will fail, or require maintenance sooner or later. Due to the beneficial results created by Thermal Cycling, however, it will fail later than sooner. Later is definitely better than sooner.

The applications for this new technology are extensive (Aircraft, Automotive, Truck Fleets, Department of Defense vehicles, Ambulances, Dump Trucks, etc.).

Finished brakes can be Thermal Cycled in less than a day.

Here is the science behind brake heat distribution. The driver presses the brake quickly to avoid an accident. The metal in the brake is immediately put under stress. Why? Because even the best mass manufactured brakes contain flaws and imperfections at the molecular level that strain the brake and limit the brake’s ability to stop without swerve or skid. The more flaws and imperfections in the brake, the more swerve or skid the driver may experience.

Now realign the brake’s molecules using Thermal Cycling by Frank Masyada. The particulate structure becomes denser and tighter, strengthening the brake and its ability to stop without swerve or skid.

While more experienced drivers may have figured out how to compensate for swerve or skid, imagine a brake whose metal is so dense there would be no serve or skid at all! How much safer would that be? And what if the brake’s life expectancy was now 2-4 times because of the density, imagine the cost savings to the municipalities and fleet operators.

In summary, Thermal Cycling:

• Optimizes the molecular particulate structure of materials
• Is not a surface treatment, application, or coating
• Enhances the material throughout, and cannot wear off
• Does not alter the appearance or coloration of materials
• Cannot be applied unevenly
• Does not require secondary processes to be effective
• Does not alter the dimensions of materials or components
• Improves other dipping and coating-type processes
• Improves the yield strength, reduces breakage
• Significantly reduces harmonic amplification (Vibration)
• Improves heat conduction for better distribution & cooling
• Relieves stresses inherent in forged or cast materials
• Enhances corrosion and chemical resistance
• Will substantially extend the life of Surgical Instrumentation
• Will substantially extend the life of Instrument trays and Containers
• Will substantially reduce brake maintenance and brake repair costs

For more information on Thermal Cycling and how it may reduce your brake maintenance and brakes repair costs by 50% or more, visit Thermal Balance Brakes, http://www.thermalbb.com. Brake maintenance and brakes repair becomes far less of an ordeal with Thermal Cycling. And given that a brake drum can weigh up to 100 pounds, fewer brake repairs is better.