1) What is residual stress and stress relief?
Residual Stress is an internal pressure that is retained by metal after mechanical or thermal straining once the source has been removed. The source of residual stress in metal can be mechanical (forcibly changing the shape of grains), or thermal (sharp temperature drop). Stress, in particular, thermally induced stress, causes three types of problems – distortion following machining or grinding, delayed distortion, and premature fatigue failures. Stress relief neutralizes thermally induced stress thereby eliminating subsequent problems. Changing mechanical properties or grain structure is not necessary to accomplish stress relief of thermally induced residual stress.
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2) How does Meta-Lax stress relief compare to thermal stress relief?
The most important comparison between Meta-Lax and thermal stress relief is that both processes achieve effective results consistently. Meta-Lax is as good or better than thermal stress relief in achieving effective stress relief results on a consistent basis. The main differences lie in the side-effects that heat has on metal. Meta-Lax stress relief does not cause heat side-effects including treatment distortion, scaling, or changing of the mechanical properties. This allows Meta-Lax to be used on many various kinds of parts that would be challenging for thermal stress relief such as finished and semi-finished parts, assemblies, hardened metals, tubular and structural steel, and non-ferrous metals. However, if any of those heat related side-effects are desired then thermal stress relief should be used. Click here for comparison in table form. Top of page.
3) How long does Meta-Lax stress relief take?
For most parts Meta-Lax stress relief treatment time is completed between 20 minutes to two hours. Top of page.
4) What are the limitations of Meta-Lax processing for size and weight?
There are no limitations as to the size or weight of the parts that Meta-Lax processing can treat. That’s because the smaller parts can be conveniently clamped to a vibration table platform whereas the larger parts would be Meta-Lax treated a section at a time. Meta-Lax processing has treated tiny heart valves that weighed a fraction of an ounce to rolling mill machinery and rock crushers that weighed over 1,000,000 lbs. and everything in between. Click here for 12 extreme examples. Top of page.
5) What are the limitations of Meta-Lax stress relief for metals?
Meta-Lax stress relief is not effective on metals where mechanically induced stresses are dominant (for example cold rolled steel plates) where machine stability is the goal. Copper and high copper content metals do not respond consistently. The edges of burnouts do not respond well to Meta-Lax stress relief. Click here for list. Top of page.
6) Can Meta-Lax stress relief be applied during welding, and if so why would one want to?
YES, Bonal developed and patented the concept of using vibrations during welding. We call this Meta-Lax “weld conditioning” or “pulse puddle arc welding.” The main benefits of Meta-Lax weld conditioning are preventing 50-95% of the normal weld distortion and preventing 50-95% of weld cracking. There are numerous other bonus benefits to using Meta-Lax weld conditioning like welding up to 25% faster, reducing (up to 300-F -150-C) preheat, reducing porosity, and more. The reason why Meta-Lax can be used during welding is because the level of vibrational energy that Meta-Lax uses is very mild and will not disrupt the welder during welding. The weld metal tends to “pack down” as solidification occurs. Click here for more details. Top of page.
7) What is the customer satisfaction rate?
EXTREMELY HIGH. Bonal hired a third party consulting firm to conduct a blind “customer satisfaction” survey of its customers over the last 16 month period. The results are outstanding. According to the data 98% of Bonal’s customers were completely satisfied with their equipment, 98% were completely satisfied with Bonal’s sales and service departments, and 93% were completely satisfied with the results. Click here for survey summary. Top of page.
8) What is the cost of the Bonal products?
Bonal has three product lines utilizing Bonal’s patented sub-harmonic technology – Meta-Lax (15 models), Pulse Puddle Arc Welding (5 models), and Black Magic (3 models). Collectively the prices range from $5,400 USD to $32,300 USD. Contact Bonal for a price quotation for the system that best fits your operation and needs. In addition, Bonal offers several CE Approved models for European customers. Click here for Product Comparison Guide. Top of page.
9) Isn’t Meta-Lax equipment similar to other vsr equipment?
Yes and NO. Other vsr equipment may use vibration to attempt to achieve stress relief, but in reality there are several very important differences that could mean the difference between success and failure. Click here for additional comparisons and references.
Difference #1 – the process. Only Meta-Lax uses the sub-harmonic energy level. All other vsr equipment use “at-resonance” vibrations which are violent, produce inconsistent results according to U.S. Dept. of Energy, and could be damaging to the parts, area equipment and shop personnel. The mild, non-destructive sub-harmonic energy level has been mathematically proven to be optimum when using vibrations to stress relieve metal. Sub-harmonic technology is exclusively Bonal’s patented technology.
Difference #2 – consistency. If consistency is not important then any vsr process will do. But if consistency is important then Meta-Lax should be the only viable vsr consideration. Meta-Lax stress relief is the only vsr process that has been able to meet or exceed the thermal stress relief in effectiveness and consistency as proven by industry and the laboratory.
Difference #3 – certification. Upon close review only Meta-Lax processing certifies that stress relief is complete – NO GUESSING.
Difference #4 – confidence. The majority of Bonal’s customers use Meta-Lax processing in place of thermal stress relief with equal or greater confidence than thermal stress relief.
Difference # 5 – capacity. Since Meta-Lax processing is mild, Meta-Lax can be used during welding mainly to prevent weld distortion and weld cracking. Bonal developed this concept which we call “Meta-Lax Weld Conditioning.” Weld Conditioning is also covered in Bonal’s patents. Using resonant vibrations during welding is counter-productive on weld quality and annoying to the welder. Click here for additional comparisons and references Top of page.
10) What does Meta-Lax do to the metal internally that causes stress relief to take place?
Meta-Lax vibrations excite metal to gently oscillate in a higher energy state than normal. As it does, areas of high stress concentrations that were caused by a sharp temperature drop use the additional energy to redistribute the stress to areas of lower stress, thereby eliminating the overall effects of stress within the metal part. It is important to note that the optimum vibrational energy level is always in the sub-harmonic zone and not at the higher amplitudes levels. This is similar to when one sits on an easy chair to relax their back with vibrations. They will realize that mild vibrations will produce relief, not violent ones. Likewise with metal – metal-relaxation works, - META-LAX. Click here for “Meta-Lax – How It Works” article. Top of page.
11) What is the life expectancy of the equipment and maintenance?
Meta-Lax equipment has been specially designed for vibration stress relief. The control consoles typically last 15-20 years, the DataGraphs last 10-15 years, and the force inducers last 25-30 years with routine maintenance. Regarding maintenance, it is recommended to replace the bearings and brushes of Bonal’s force inducers every 2,000 operation hours (or about 3,000 average parts), and recalibrate the transducer every 1-2 years. Top of page.
12) Who endorses the use of Meta-Lax technology?
Meta-Lax technology has been verified by over seven major organizations including U.S. Department of Energy. There have been over 165 published articles in trade magazines of which over 125 of these included pre-approved case studies from Bonal customers including NASA, U.S. Navy, and General Motors. In addition, Bonal and/or Meta-Lax technology have received Special Awards and Recognitions from National Science Foundation, U.S Department of Energy, GSA, and finalist for the Entrepreneur of the Year for 2008. Click here for U.S. Department of Energy’s Tech Brief. Click here for a several customer comments taken from customer approved published articles.
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