FEATURED VSR APPLICATION :
Forged 6061 aluminum ring
Aerospace tooling for the SpaceX Program is setup for VSR Processing, using a T-slotted fixture. U-shaped workpiece was clamped in three spots (minimum number to determine a plane) and raised / separated from the fixture by 3/16" shims (one visible in left foreground). Stress relieved in 1 hour.
VDW / Vibration During Welding :
Controlling Welding Distortion Safely
VDW / Vibration During Welding
Drill rig masts which telescope together are being welded on left, with distortion kept to 3 mm over 5 m (1/8" over ~ 200") using our pneumatically powered 3D VDW System. After welding, which required NO STRAIGHTENING after fabrication, these components were VSR Processed, which allowed them to maintain excellent dimensional accuracy during machining. On right both frames are nested.
Previously, distortion / straightness of these frames was in the range of 6 to 12 mm (~ 1/4 - 1/2 inch).
VDW reduced distortion between 2 - 4 times.
Elec arc furnace base VSR Processed in 3 hrs
A hydroturbine discharge ring was used as a teaching aid to VSR System operators.
Elec arc furnace base VSR Processed in 3 hrs
VIBRATORY STRESS RELIEF (VSR) is an industrial process often used to assure the dimensional stability of a metal structure. Vibratory stress relief is often used after welding and before machining. Effective vibratory stress relief causes flexure of the workpiece that combines with internal ("residual") stresses, resulting in plastic flow thru grain migration, within the material.
For many stress relief applications, effective vibratory stress relief is a suitable, at times, superior substitute, for thermal stress relief.
Metal components that have high levels of residual stress also have increased damping, which suppresses the amplitude of resonance peaks. Successful stress relief incrementally removes this suppression, allowing the peaks to grow to higher amplitudes, eventually stabilizing. Often such peak growth is accompanied by peak shifting, typically in the direction of lower frequency, but shifting to higher frequency can occur, and is often an indication of change in workpiece shape.
By recording, displaying and tuning upon these resonance peaks, the progress of a VSR Treatment can be monitored and documented. Examples of such VSR Charts can be found in the Library, in VSR Reports. There also is a Technical Library, where much of the best and pioneering research in this field can be found.
Advanced VSR isolated the phenomenon of damping reduction in the early 1980's, and has used this mechanism to design both vibratory stress relief equipment and procedures that maximize the effectiveness of the VSR Process and make easy the documentation of effective vibratory stress relief.
The slide show above shows examples of both vibratory stress relief equipment and applications.
A PARTIAL LIST OF ADVANCED VSR USERS
Adira / Portugal
Advanced Technologies Inc.
Anglo American /Brazil
DBC Makina / Turkey
Ebco International / Canada
E. D. Industries
Fives / Cincinnati Machine
Howden / TLT Babcock
Ingersoll Machine Tools
Kovit d.o.o. / Slovenia
Lufer / Brazil
Maintec / Australia
Mainland Machinery / Canada
MCS / Metal Cutting Specialists
M H Eby
Northern Valley Machine
Ormat / Israel
Polat Makina / Turkey
Precision Custom Components
R J Florig
Rock Island Arsenal
Sanggar Sarana Baja / Indonesia
Schoeller Bleckmann Oilfield Eqpt / Vietnam
Superior Die Set
Three D Metal
Voith Hydro / USA / Brazil / Germany
Wendt / India
How Does Vibratory Stress Relief Work?
Metal components are stress relieved without the use of heat.
Instead, they undergo vibratory stress relief (VSR). This process utilizes precisely-controlled vibration to record the resonance pattern of the metal workpiece.
During VSR, peaks often grow and can shift to lower frequency. Shifts to higher frequency can indicate inevitable changes in workpiece shape.
- Machine Tool Bases & Columns
- Hydroturbine Components
- Paper Mill Machinery Components
- Water Way & Storm Surge Gates
- Automotive & Aerospace Tooling
- Lifting Devices, Cranes, Yokes, & Clamshells
Why Vibratory Stress Relief?
- Cost Saving Technology
- Time & Energy Savings
- Quality Improvement
- Enhance Structure Integrity
- Control of Manufacture
- Prevent loss of physical properties caused by heat treatment
Other links to technical papers on VSR Technology :
WHY AN INVESTMENT IN AN ADVANCED VSR SYSTEM IS YOUR BEST CHOICE
- Software plots not only workpiece amplitude vs. honest vibrator speed data, but also vibrator input power. This provides the operator the info needed to achieve the best practice VSR setup
- Super-low-noise, clean vibration data makes clear to the operator the steps needed to perform the VSR Process
- Only the newest technology components, from motor drives to PC's to motor technology
- System-wide plan to prevent excessive heat or vibration assures years of high-reliability performance, designed by PM (Preventative Maintenance) heavy-industry professionals
- Resonance-based vibratory stress relief is both most effective and fastest, as shown by independent research
Want to see more ? Go to VSR SYSTEMS
- Double-gasket sealed enclosure prevents dust, dirt, oil or sprayed water from entering the enclosure, whether in storage or operating mode (NEMA 4 / IP65), preserving long-term electronic integrity.
- Full powder coated with galvanized
rear panel (motor drive mount)
- Allen-Bradley motor drive with xternal heat sink
exhausts 80 % + of heat outside the enclosure
- Full-ground plane design using the Faraday Box
concept prevents EMI noise from entering or
leaving enclosure together with process signal
isolation between motor drive and PC keeps
vibration data clean and clear
- CNC machine tool grade 15” / 380 mm
touchscreen display has no mechanical
elements, such as fans or rotary hard drives.
- Main-Frame construction with removable back
panel, so that advances in motor and motor drive
technology can be installed easily.
- Embedded OS
- Speeds up to 9000 RPM, which expands the range of workpieces into both the very rigid and heavy and those of modest size
- Tight speed regulation, as low as 0.03%, with no warm-up drift, a problem that plagues motors with brushes
- Thermal sensors protect the motor from heat, with full display of motor temperature
- Dual flanged vibrator (Model 8a and 8b) can be operated in any orientation, which is mandatory when treating certain workpiece shapes, such as large rings.
- Rugged connectors with spring strain reliefs keep cabling functional, even in tough industrial environments
Combining these elements, together with our robust technical support has allowed dozens of shops to produce a steady stream of dimensionally stable, accurate, predictable precision parts.
This 6061 aluminum ring displayed signs of residual stress during rough machining. It was VSR Processed using a fixturing technique developed by Advanced VSR. Machining to roundness tolerance of less than 0.003 inches was then achieved.
WE INVENTED THE VSR PROCESS
Advanced VSR is a company that offers vibratory stress relief equipment and services, and has been a pioneer in the field since the 1980's. The fact that resonant vibration is most effective in relieving stress (several independent research papers state this point) and that vibratory stress relief causes a workpiece's resonance peaks to grow, shift or a combination of both, are just a few of our many discoveries.
Our research has been published by both the ASME and ASM, copies of which can be seen in our VSR Technical Library.
V16 diesel engine blocks are one of many VSR applications. According to Frank Janiszewski of Superior Die Set, Oak Creek, WI :
" We have been using VSR Technology for more than twenty years. One particular application is noteworthy : V16 engine blocks diesel or natural gas generators.
Prior to using the VSR Process, the success rate for achieving final machining tolerances on these engine blocks was less than 50 %. After these blocks were regularly VSR Treated between rough and final machining, that success rate went above 95 %.”
Line bore tolerance was 0.04 mm, full length.
After VSR Processing was started, more than 95% met this critical tolerance.
Superior Die Set has been using VSR Technology for 20+ years and is currently using our Model 8b VSR System, and discusses their use of VSR and its benefits on their website :
VSR Treatment Chart made using a Model 7.5 VSR System. Upper plots are acceleration, before (green / baseline) and after (red / documentation) stress relief treatment. Note that all resonance peaks grew, while the broad peak at ~ 3600 RPM also shifted slightly to the left. Upper plot is calibrated in acceleration / g's. Lower plots are vibrator input power, again green = before / red = after. Poor vibrator location would result in much higher power peaks, thus the importance of plotting power. Horizontal axis is RPM. To see the VSR Report containing this chart, click here.