Investigation report WIAP MEMV 2013
Review Metal relax with vibration from Switzerland in 2013
WIAP Metal relax with vibration since 1981 Experience rearview 1981-2013 = 32 years WIAP metal relaxation facilities Sven Widmer, Iris Widmer Hans-Peter Widmer, November 2013 r9
Investigation report WM820
CONTENTS 1a. Introduction 1b. Photo information 2. Why the welding distortion 3. Technical challenges 4. Review 5. Today's state of WIAP LC systems 6. Time advantage while relaxing with vibration 7. Vibrate during welding 8. User Information 9. WIAP vibration relaxed own machine 10. The WIAP DK 20 data communication device 11. Metal relax with vibration 2013 12. Material differences 13. Other equipment manufacturers 14. Glowing kinds where the vibrate belong 15. Conclusion
1a Introduction
Residual stresses are internal stresses that are characterized in balance, that is present adjacent components, train and compressive stresses. But the external stresses are superimposed whereby the outer bearing capacity can be sensitively reduced. That is why the desire to have power arms factory malice is also explainable. Metals are fixed and simultaneously deformed. Metals consist of atoms in a regular arrangement, a crystal lattice. Thus the form of a metal changes permanently, the atoms must move against each other so that atoms were adjacent previously, after a difference. The metal relax with vibration obtains this shift smoothly and uniformly over the entire workpiece. It is a process that replaces in many cases, the stress relieving. It can be placed as an intermediate stage before the tension arm glow. Predominantly an ideal method for welded constructions in mechanical engineering, machine tool manufacturing, plant engineering, stainless welded structures, pressure and vacum tank, and much more.
Many experiments have shown that the vibration Relax is an excellent alternative for stress relieving. The WIAP has built many custom tool machines, which have to work precisely in hundredths of a millimeter. So many own test's could be made. For the WIAP it is today an important reason that the metal relax with vibration, the complicated engineering, these massively relieved. It was possible to save days at the dates and thus a lot of money. With metallographic investigations and neutron diffraction, the test results were not as clear as with the measuring method X-ray diffraction. Here it was found that a voltage reduction of about 25% in vibration relax, as well as the vibration during the welding could be achieved.
The X-ray diffractometer is used to crystallography to make crystal structure analysis. Residual stresses are stresses that exist in a body. Associated with residual stresses and deformations such as warpage during welding.
Thermally induced residual stresses can also arise in that the edge and the core of a workpiece to cool different after appropriate heating. Through the rapid cooling of the near-edge portions can there come to tensile stresses due to inhomogeneous cooling. After the temperature equalization between the weld seam and the workpiece, then there is the formation of compressive residual stresses, mainly in the edge region. The resulting cooled core is too short, the material difference is compensated for by plastic and elastic elongation of the body 1 relative to the shortening of the body 2 and the corresponding voltages, which glow by tension arm or vibration can be reduced.
The measurement of residual stress can be measured nondestructively and destructive.
Non-destructive measurement methods include radiographic residual stress measurement. EBSD. Hereby the stress of the metal grid is determined as a result of the prevailing voltage. This method is limited only to the near-surface zone. For steel, the information depth in the range of some micrometers.
Residual stress measurements by neutron allow greater penetration depths. Our method can also detect metal relax the results with vibration, this shows the years of practice.
Residual tensile stresses at the surface have a negative effect on the fatigue strength of a workpiece.
The vibration relaxation occurs in the first 10 minutes of the vibration process such as the voltages lying in the uppermost micro range degrade shortly. However, deeper tensions difficult to measure with the non-destructive measuring method are changed by the vibration. So atoms with vibration to be moved.
It should be noted that the weld is faced with about 3200° and the next underlying material with low temperature wants something different. What happens there? There is tremendous work tension, which we reduce by silent glow as an alternative to low stress.
1b. Photo info WIAP vibration relax
Stainless tank of Swiss clients in vibration relax.
Thin-walled, large welded construction is in central Switzerland with vibration relaxed in 2012.
German conglomerate expanded in China in the production, all parts with vibration.
Swiss conglomerate relaxed for decades all stainless worm waves with vibration. In waves are the chuck devices more complicated.
Swiss manufacturer relaxed 12 meters workpieces. The special feature, these parts were directed with warmth. That is, locally heated so that they were straight. The delay was before many mm. Relax without vibration, the workpiece warps after editing. Relax with vibrating the delay is less about several times.
Rolling of a Swiss customers that are welded multiple layers and hard chrome plated for it and should run around in thousandths. Also, the hard chrome plating caused a delay that makes it difficult to manufacture high-precision rolling solid; respectively, even more expensive.
2. Why the welding distortion
Mainly during welding parts which are welded cold, the workpiece can be moved in many directions by the high weld seam temperature of about 3200°. This causes uncontrollable default. Heat is moved contribution dependent. However, depending on the welding plan preparation, this can be also affected. Also, workpieces with many local welds, subsequently by the unequal distribution of heat, straightened again. Often with heat, or by mechanical agitation, but this leaves additional new large voltages in the workpieces. In general, by a thermal annealing, or by the metal relax with vibration, this voltage is greatly reduced.
3. Technical challenges
As a life-time lubrication a term is expected from 20,000 hours in the machine tool in spindle bearings, we have also sought this goal. By the pathogen is built like a machine tool spindle. Robust and designed for overload.
The robust screw clamps, which produces the WIAP, are necessary to prevent fluctuations in the protocol test results occur. The excitation reconnect to untreated locations on the workpiece, requires a strong clamping. Especially if the critical speed is reached and is headed for the supercritical speed, the cause must be very rigid with the workpiece so that the zone of the critical speed can be safely crossed. In general, the WIAP relaxed in the supercritical speed range. It must thus be always driven through the critical speed range. An additional exciter base plates press, improves the clamping on unprocessed surfaces.
4. Review metal relax with vibration
We work with the method since 1981. Since 1983 we build our own WIAP relaxation facilities. The first WIAP LC system was the WIAP LC type A. Made further developments later. Today we are in type D. Already more than 20 years, the first 50 tonnes plant was built. Extended again and the electronics, integrated PLC were so relaxing. Years of in recent years, several thousands of wage-labor operations, mainly in Switzerland, renovations have brought in the next generation of devices and over again.
5. Today's state of WIAP LC systems
The most produced WIAP relaxation plant is the LC 20. Designed for a maximum workpiece weight of 20 tons. The LC 50 for 50 tons and the LC 05 for 5 tons of plant have already been delivered. The LC 100 (100 tons) and LC 200 (200 tons) investment in the factory. Therefore smaller workpieces can be relaxed even with the large investment, the systems are combined today. An LC 50 can also be left running with an LC 05. At the control device is set with a selector switch which V-excitation is used. 5 tons, 20 tons, or 50 tons device.
In 2011 has been the new data communication device WIAP DK20 developed which automatically transfers data via wireless to the PC. This extension logging greatly simplified. Especially among the newcomers around and for quality assurance. By 2011, however, all WIAP customers have the system of manual logging of WIAP LC system applied. Also, this system has proven itself for decades with the WIAP plants. The new WIAP DK 20 is provided for retrofitting previously delivered equipment.
The LC 20 pathogens relaxed a WIAP machine bed.
A WIAP big machine bed with guides 8 is expanded with vibration.
6. Time advantage while relaxing with vibration
If tonight a machine bed was finished welded, it can be relaxed the next morning with vibration. Following our exciting tables:
7. Vibrate during welding
Experiments also showed that vibrate during the welding, also a variant which leads to a good result. Here can be energized in a deeper Hertz area because the work is a long time in excitement.
Recently, a university has made an investigation and confirmed that the default if vibrated during welding, by about 25% reduced. It is expanded in the mode of application in a lower frequency. Here, too, by the local temperature fluctuations, a residual stress can be eliminated better after cooling, and then again with vibration relax.
8. Application information:
· A Swedish welding machine manufacturer has bought a WIAP LC system. · A German / Swedish conglomerate, active in turbine has a WIAP LC system for a few years. The system is in use daily. · A Swiss customer from eastern Switzerland was one of the first to 30 years ago, acquired a WIAP system. He was still relaxed, now in 2013, with the plant. · A Swiss army vehicle manufacturers once delivered to NATO vehicles. In Switzerland, everyone was ok. Arrived in northern Europe, had a majority of the vehicles, several hundred mm long cracks in the troughs. During the subsequent repair welding everything was vibrating. All new vehicles were relaxed during the manufacturing process with vibration and there were no more tears. · A large Ukrainian plant belonging to Gazprom, with 12,000 people, has bought a plant from the United States in the 1985. A few weeks ago a new plant WIAP with data communications device DK 20 was commissioned. The customer has a QA system and has bought a new plant because it relaxes with vibration since 1985. · A German large company has a plant in China. In 2012, a new plant WIAP was purchased. The customer had a plant in China, which they have then replaced by a WIAP device. · A Swedish CNC lathe manufacturer has since 1985 a WIAP vibration system. All lathes structures were changed and adjusted at the time. There were built hundreds of machines after the procedure.
9. WIAP vibration relaxed own machine
The WIAP built four large CNC lathes WIAP DM4 C 2 produce in Switzerland, 2 produce in Africa, in Angola. Special designs, i.e. special machines were built for several large corporations. The vibration relaxation was a major reason for short delivery times. The cost and the date. Even with the vertical lathes WIAP DM2V with top hanging headstock, all welded structures were relaxed only with vibration.
In 1997 a Swiss customer ordered a large lathe WIAP DM4C; weight 24 tons. The machine bed alone 13 tons. In addition to the bed 16 other components were relaxed with vibration. |
A Swiss customer ordered such machines WIAP DM2V for the mass production of a large company of Lichtenstein. In the machine are 12 components which have been laid with vibration, in addition to the machine bed.
This diploma was exhibited at the International
Exhibition of Inventions in Geneva for the Vibration dampening
method for machine tools, which are connected with metal relax with
vibration. Patents that have been created in the matter
Diplomas at the International Exhibition of Inventions in Geneva 4 x 1994 and 2 x 1996
Patent Germany. A part of the patent specification 42 30 103 is metal relax with vibration.
Patent Switzerland. Integrated: metal relax with vibration. 10. The WIAP DK 20 data communication device
The data communication device WIAP DK20 was realized in 2012 and has the following functions: It determines the relaxation process the change during the expansion process.
It keeps the status firmly about 2 minutes after the start of the expansion process of subcritical or, preferably, supercritical point. Since the data collection point starts when 30 seconds no more regulation, a speed readjustment is made again, it the process starts all over again. The current process to complete the plant is set to the years of empirical values of our wage labor contracts and own projects that we execute since 1981.
Shortly before the vibrating end is usually determined after 30 minutes the value again, then the whole process is noted by calculated and displayed on the data communications device with the indicator lamp the value of the metal relaxation. It indicates with a light indicator, if a good, medium or low relaxation process is done. This is especially important that the surgeon does not have to decide for themselves whether a relaxation took place or not. This is mainly important for quality assurance.
WIAP DK 20 device, data communication
In addition, the value is stored in an Excel spreadsheet, sent over wireless on the laptop, which is always connected during the whole relaxation process with the WIAP LC device and holds all the data and change. Also on the table is the additional Excel Calculation with the result, good relaxation process, average relaxation process or weak process still shown separately. The workpiece number, subscription number and other data are entered in the Excel form. Here the WIAP metal expansion plant has taken a step forward for the benefit of future quality assurance.
WIAP relaxation concept with vibration
Sample Protocol of WIAP DK 20
A special feature of vibration relaxation is that a workpiece is evenly excited. This can be achieved if the workpiece-related vibration node is not centered. That is, the pathogen is not attached in the middle or outside, but after the 1/3 - 2/3 system. As a result, the workpiece can be brought evenly over the critical speed in order to relax supercritical speed range metal. With a modal analyzer, the point can also be determined accurately. But Wiap's over 30 years of experience shows that this 1/3 to 2/3 principle spares the modal analyzer. The excitation takes place via a vibration node. These differ depending on the material and rigidity of the workpiece. That is, the critical speed can therefore be in the Hertz range of 50 Hz in light constructions to 60 Hz in rigid construction. As a rule, it is desirable that the noise does not exceed 90 db. Please pay attention. When the G exceeds 8. (100 mV = 1 G) or the dB increase above 90. Reduce the exciter mass with the eccentric disc. Each workpiece usually has 3 critical speeds, over the first can be driven without problems about it. The second, depending on the rigidity of the workpiece even, but then before the third critical zone can also be overrun at very stiff and supercritical relaxed. In light constructions, the third critical zone should not be run over. For rigid constructions, the Hertz range is 80 to 100 hertz. For normal designs 55 - 70 hertz. Very important, the pathogen must be clamped with many tons that no data falsification interferes with the process. Or, if the self-resonance point i. If a resonance catastrophe is indicated, the exciter must be rigid, inseparable, connected with full force to the workpieces so that the workpiece is prevented from entering the resonance catastrophe. It should be noted that the pathogen with its tons can flow, especially on the lateral forces has a great impact. Therefore, the clamping force of the screw clamp must clamp about 10 x more than the lateral force is able to bring in. In addition, it should be noted, when signs of a resonance catastrophe arise, it is very important that some of the normal lateral force can clamp the clamps. Only then is the workpiece under the control of the surgeon and not the operator under the control of the workpiece.
It should be ensured that the start up of a relaxing process about 3 Critical zones are crossed. It comes in different flexural vibrations during the startup process. There are varying antinodes and between the excitation points they overlap too. With the pathogen even and odd anti-nodes are created. If there is an even number antinodes the natural resonance zone is not excited. Harmonic oscillations are oscillations with a sine-shaped Schwingungsgverlauf. Relax with the vibration and a harmonic vibration course is searched for and obtains. Its course is often a very complicated, periodic function of time. A non-relaxed work requires more vibrational excitation energy after about 10 minutes running time, the power consumption of the pathogen reduced by a few% and the G value, the amplitude / acceleration is reduced. So the system oscillates with the frequency of the exciting force. If this frequency is much less than the natural frequency of the system, it will follow the external force with no phase shift. At very high frequencies the system and the external Kaft swings, however, out of phase. And in the field of resonance. At very high frequencies the system and the external Kaft swings, however, out of phase. And in the field of resonance. At very high frequencies the system and the external Kaft swings, however, out of phase. And in the field of resonance.
Thanks to the fine adjustable setting of the pathogen of this critical point can always within fractions of a second run over and be worked around a resonance disaster. However, it requires constant supervision of an operator of a plant, especially in new part series. If always the same workpieces are made, a casual observation type can be type approved. It should be noted: At low excitation with the excitation system of external force follows. With rapid stimulation it vibrates in opposite phase, and often at resonance. A distinction must be free and forced vibrations and our system, Metal relax with vibration obtained a The latter and the system has a voltage degradation takes recognizable by the smaller amount of energy between the before and after the vibration process. And the amplitude, respectively. Acceleration is greater in a tense work and after a short time, this workpiece clamping often reduced by a few percent, which is also the confirmation that a stress relief is done.
11. Metallenstpannen with vibration 2013
Based on the weight of the workpiece, the vibration method leads into a high amplitude and low frequency vibrations for a fixed given time period. This eliminates residual stress without deformation or change in tensile strength, yield strength or fatigue resistance and the static equilibrium is again we reach made
Die efficient vibration relaxations if we vibrate in
the supercritical range and strongly attenuated vibration controlled 30
minutes energized blank. If the 1/3 - 2/3 excitation system - is arranged
controllable chucking system of vibration nodes can be reported the best
results.
Die relaxation time must be determined according to the time table. If the relaxation time is exceeded, the workpiece is getting no damage due to fatigue or loss of tensile strength reached, unless it is relaxed with too long a time on the critical point with an exciter stage having a excessive G value wird. If obtains workpieces large or are long, or have large open spaces, it may be necessary to fix the method to a second or third point. This is required when the oscillation node is located within the knot zone of the workpiece.
Usually described below should be followed for all applications:
a) Support the work piece in the best possible way with
the 50 shore rubber. So that the workpiece can vibrate freely min 80 mm
thicknes., better 120 mm or 200 No connection to the ground or not connect
to rigid structures.
c) The V vibration exciter should the workpiece with good, robust connections part connect.
Vibration relaxing method can be used on a wide range
of iron including steel and stainless steel, cast iron in a variety of
forms. 12. Material differences
For ferritic or austenitic steel different characteristics are still in the evaluation and be formulated. Steel structures. Stainless constructions was used by us to this day the most.
13. Other equipment manufacturers
There are several manufacturers of vibration relaxation facilities. Established strong has this business segment in the United States. Already from the 30-ies are found treatises on the subject. As well as the aerospace and defense shows intensely busy that the method to good use is met. Many machine manufacturers or plant engineers realized that the vibration relaxation is an alternative to glow. Also from the cost side, there is no way the metal relax with vibration passes. It is also good that there are now more vibration relaxation equipment manufacturers. A good competition promotes the technology and are also generally confident in this, promising today method. Today there are some vibration relaxation equipment manufacturers from the US, Russia, China, India, Romania and of course we who informed us from Switzerland / Europe, with experience since 1981. There used to Swiss precision parts manufacturer that they had to leave their 15-meter-long workpieces ride on the railway cars in Switzerland around in front of the finished edit earlier. Only they had the certainty that the thousandth Tolerance could not by default after finishing are complied with. Since this vibration contribution was uncontrolled, it was necessary that product to let go more than three months on railway cars in Switzerland around.
14. Glowing kinds which belongs towards the vibration
The metal relax with vibration not fulfill all the tasks of the thermal treatment. It eliminates any hard spots in a workpiece.
When cold drawn material, the uppermost layer that can is located in the micro-range are not removed.
The metal relax with vibration is a method of the annealing, the tension arm in many cases replaced resp. added. It does not replace the recrystallization annealing and normalizing or homogenizing.
Here information about these mentioned glowing kinds / Vibration relax. Metal relax with vibration. It is 30 minutes by vibration on the second or third critical point at about 50 to 100 heart vibration Relaxed usually not more than 8 G. The workpiece must lie on rubber to work without exciter damping. It should be allowed only a weak node, should be vibrated when only one setting. Stress relief takes place and causes internal stresses of the workpiece to be removed which have been introduced by mechanical deformation or processing at relatively low temperatures between 480° C and 680° C. Otherwise, the steel properties are not possible to be changed. Recrystallization refers to the recovery of crystallite forms as they have been present prior to cold working. To this end the workpiece is usually heated to temperatures just above the recrystallization temperature between 550° C and 700° C. The recrystallization temperature depends on material and degree of deformation Normalizing of steel is one of the most important heat treatment process. It aims at the formation of a fine-grained microstructure of crystallites which are distributed uniformly over the workpiece from. For steels with higher carbon content, the annealing temperature is just below 800° C; in steels with low carbon content, the temperature for annealing normally rises up to 950° C. Diffusion annealing lasting for up to 2 days, will take place at quite high temperatures of 1050° C and 1300° C and is intended to ensure an even distribution of impurity atoms in the metal lattice. The cooling speed determines the formation of the phases, and thus the steel properties.
Glowing
mats_glow Recrystallization annealing is not in the old tech. Literature found. By contrast, you can still find such glowing words stress relief. D, h There have been in recent years, many new findings mean that can be manufactured cost-conscious. Low stress that the glow and recrystallization is no scale shows the importance the treatment. That metal relax is settled with vibration glow against the tension arm. It still has the enormous advantage that the material-dependent temperature variation must not be ignored. As is necessary for the two methods stress relieving and recrystallization annealing, also means that the vibration relax a quick cost-conscious variant, it is to be used.
15. Conclusion
Metal relax with vibration stress glow as an alternative? If this is the path that can save a lot of energy? In the earlier years, there was a large number of foundries around the world. For that reason, many large series were produced. Each casting is indeed a model needs that has ever tasted a high amount. Today in 2013 the welding technology has changed a lot. ES were also closed some foundries. Thus the possibilities to have a work / glow in many places without tension stress. When the vibration relaxation has been recognized for many decades, the demand was not as aware as they are today. But even then it was aware that large structures can be worn in an oven not so readily. Now, this variant can be used as an alternative. Also, in order not to let a workpiece often transported hundreds of kilometers on the road to the thermal relaxation. Thanks to the logging and today's electronics also problem-everything can be Logs, allowing the quality control.
Metal relax with vibration is an excellent system for welded structures, time saving, cost saving
Please contact us for any further information.
We appreciate that you took the time to read our documentation. If you have questions, please send us an email to wiap@widmers.info
Thank you Gruss Sven_ Iris_ Hans-Peter Widmer
Manufacturers and sales, research and studies, design electrically and mechanically, all from one source
Industriestrasse 48L CH-4657 Dulliken Telefon: ++41 62 752 42 60 Telefax: ++41 62 752 48 61
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