Description of the flame straightening - process

This method is used for straightening deformed components,

correcting the delay of welding constructions and for directing

and profiles large-area parts.

Also thin sheets like box structures, machine beds, machine

stand are typical tasks for flame straightening.

A portion of the metal is determined by the acetylene limited

oxygen flame locally heated. It occurs as a result of disabled

thermal expansion, a permanent squeezing. That is, it has

between the zones of the discolored area and the uncolored

area a different voltage than the focus of discoloration. Thus,

desired forms again getting produced.

In addition, flame straightening can to molding are used.

P2: The component was directed flame

It can, for example when welding a incurred angular distortion

are addressed, a slight bend be achieved by plates bending profiles

strong, crooked steel plates or warped frame correct and even

the diameter of cylinders decrease. (What safe only as a stopgap

should be).   

P3: Flame straightening point

When machining general structural steels, fine grain and austenitic 

toughen with a carbon content of more than 0.05% should be a

oxidizing flame be used.

The temperature of 650°C (red heat) should be in this case not

exceeded.

For aluminum and aluminum alloys should the temperature no

higher than 350°C to 400°C and is dependent on material and

alloy. In this connection should be a neutral flame with light

acetylene used.

P4: The component having a plurality of heating bodies by flame straightening.

Advantages of flame straightening - process.

1. Unrivaled efficiency and effectiveness the oxy-acetylene flame

2. Faster and material gentle removal the workpiece delay

3. Clearing of welded delays instead scrapping

4. For all metallic, weldable materials suitable

    (High-strength steels only suitable)

5. DVS - certified procedure for approval DIN EN 1090

6. High mobility. (Use without power supply possible)

However, flame straightening causes a new problem: namely

the delay in processing. Annealing after flame straightening result,

that the component in the original warped position moves back.

After this new WIAP® MEMV®  Method, there is no delay to

the processing. That is the WIAP® MEMV® Relax eliminated

in the intermediate zones, where it passes through the flame

straightening was red hot and the uncolored zone where a

compression took place, tensions. This, stresses generated by

heat are, distributed by the vibration margins so that between

the cold compression zones which by flame straightening not

revealed to the WIAP® MEMV® distributed process and thus

prevents a delay in the processing. 

P5: The component loses scale by WIAP ®MEMV® process

P6: The measuring probe records the process

P7: Very important is a good rubber underlay. This should have a

sufficient height so that no vibrations are transmitted in a factory

building. In addition, the logging is accurate.  

P8: About 20 tons of the workpiece weight. The WIAP AG has

facilities for 5, 20, 50, 100 and 200 tonnes

An alternative to the tension arm glow. Thanks to the new improved

methods WIAP® MEMV® 

(Metal relax with vibration)

If we take a hot-rolled construction, which is warped by torsion and straightness

in several mm, this flame judge, then bring in the annealing plant, the work comes

after annealing, by the influence of heat, back into the warped base position. 

With the WIAP® MEMV® Method, the flame directed workpiece vibrates.

The axis-specified eccentric stages setting allows the excitation process can

also take place with a maximum speed without too extreme deflection occurs.

All axes are touched. With 24 measuring points the exact course and the changes

are determined and recorded. When following machining the workpiece is

not slow. That is, the vibration can relax now with the MEMV® relaxation method,

advantages over the glow, because balance the tensions.

The merit of MEMV® WIAP® procedure summarized:  

• Set up a component and edit it, it warps.
•  Set up a device, it vibrates to the new WIAP® MEMV® Method,                            there is no after processing delay.
• Set up a component and enter it in the annealing plant; disfiguration                                it again. To set again, edit it and warp again. 

This new and improved WIAP® MEMV® method is the key to why the metal relax with vibration has an advantage compared to the annealing.

It is also important to know that it has been stated that the vibrational relaxation

locally to zones, not only heat, but also with vibrations, stresses degrades specifically

controlled so that no reset delay a directional component takes place. 

However, it is very important to carry out a 100% controlled vibration relaxation.

It takes a very good attachment between the component and the pathogen. The

introduction of energy direction plays an important role. The in one component

always present dead centers must resp determined are always well attended. 

The following protocol shows the current measurement in the process according            WIAP® MEMV®.

It is a component today considering 24 measuring points, so that the change

between before and after in many places is determined. The difference we

measured after about 90 seconds. The biggest stress relief is, however, at the

very first load cycles. This we collect but not currently. The advanced detection

method is with us in preparation.     

Where tensions go towards the MEMV® process?

The not relax with heat but vibration?

regarding the question where to go toward the tension, I would like to answer

briefly.

Flame-looking components generated by the introduction of a local thermal stress

state of communicating with the environment in balance.

If this component is annealed arises through a free deformation, a new state of

tension and the component is crooked. Was the case of a flame-directed component

which are overlaid by local equilibrium states that the macroscopic equilibrium states straightened, these local equilibrium states are disturbed by the processing and the

component passes through a deformation in a new state of equilibrium.

If the component is annealed in a clamped state and cooled clamped slow the global

tensions in balance and subsequent processing will not have a major influence on the straightness.

When vibrate in the clamped state in several directions, the stresses in the global state

are brought into balance, and the component can be edited. The voltages are not only

on the surface but also in a greater depth in equilibrium.

I hope to have explained to you with this short version, where the tension go.

Created: Iris, Sven and HP Widmer

Answer where tensions go towards the MEMV® method

response from Prof. Schmid