DE102007031929A1 - Heat process to cut metal or non-metals with a beam alternating between maximum and minimum in the presence of mechanical oscillation - Google Patents

Abstract

In a heat process to cut metal or non-metals, the cut is effected by a flame, plasma beam, laser beam or electron beam. In the process, the beam alternates briefly between maximum and minimum, creating a brief maximum temperature difference between the cutting beam and the workpiece, thereby limiting the local thermal stress within the workpiece either side of the cut. Further, mechanical oscillations are introduced to the workpiece either side of the cut, forming a separation line, fraction line or zone of reduced strength. Should a residual bridge exist between the two halves of the line following the heat process, the two halves are separated by mechanical action.

Description

[Description of the invention]

method for the thermal separation of materials with a cutting jet, in particular electron beam.

[Description]

The The invention relates to a method for the thermal separation of metals and non-metals with a cutting jet. The cutting jet can a fuel gas oxygen jet, plasma jet, laser beam or electron beam be.

[State of the art]

It Various thermal cutting methods with cutting jet are known. In these processes, the material becomes hot Cutting jet locally melted and the molten material blown away by the gas pressure. With the gas becomes conventional Flame the material at the same time oxidized, leaving slag produced with low strength. Along the treated cutting or parting line remain at least at the edges Schlackereste. Also for other reasons, the surface of the cut material pages irregular and often has to be subsequently mechanically smoothed become.

For safe separation of the material and blowing out the slag a certain joint width is required. For what appropriate gas quantities or energy are necessary. A higher cutting jet temperature and a higher gas pressure allow narrower kerfs. The required slag discharge must be guaranteed. To promote the removal of the slag it is from the DD PS 107226 known to put the cutting beam in ultrasonic vibrations. These vibrations are transmitted to the gas emission source. From practice, such a solution is not known. The cause could be the insufficient effect or the vibration load of the cutting torch.

The Application of ultrasound is also for welding process known. In this case, ultrasound with so-called sonotrodes transfer the pressed together parts to be welded. By The boundary surface friction on the materials creates heat and the material melts. Due to the contact pressure, the parts then welded. Field of application is the welding of Plastic.

OBJECT OF THE INVENTION

task the invention is to provide a thermal cutting method that a minimum parting line to jointless separation area and thus connected has a reduced to no slag discharge. This method is intended to reduce energy consumption, the surface of the joint edge and the cutting accuracy improved and reduced pollution by ejected slag become.

According to the invention solved the task according to the features of claim one.

After that becomes in a thermal cutting process with cutting jet in the cutting area briefly a maximum temperature difference between cutting jet and material produced so that there is a localized high internal material tension is effected, and at least in the cutting area of the cutting beam on one side or both sides of the cutting line in the material mechanical vibrations are introduced to a Parting line, material cracks or a zone of reduced strength to create. At a residual binding force remaining after the cut In the intersection of the material, this is due to mechanical action canceled.

The Method is based on the realization that in many materials strong for short-term localized heating internal tensions arise. This leads z. B. in electron beam welding from metal to fractures at the grain boundaries, giving the strength the weld reduces. According to the inventive principles are when heated with a Cutting beam through the additionally introduced mechanical Vibrations intensify the stresses, causing material cracks in the material Cutting area is coming.

Becomes the material is melted, or is formed by the oxidation slag, prevent mechanical vibrations during cooling a reconnection of this material. It thus creates a narrow Zone with very low strength, or a very narrow parting line, from the barely slag is ejected.

The allow to be generated narrow heating and melting zone not only narrow kerfs, but also lower energy consumption. Due to the generated crack structure in the particle size range the cut surface looks smooth.

Advantageous embodiments of the method to the vibrations used and their introduction into the material are contained in the claims 2 to 6. According to a preferred Ausfüh According to claim 2, the mechanical vibrations in the ultrasonic range and frequency and amplitude are changed depending on the material to be separated material and the material structure.

To Claim 3 are oscillations with a frequency of 1 kHz 50 kHz used.

To Claim 4, the vibrations from a converter over an amplitude transformation piece and a sonotrode directly directed to the material.

According to one preferred embodiment according to claim 6 soft on both sides the intersection of the introduction of mechanical vibrations in the material the frequency and / or amplitude for the sides from each other. This significantly increases cracking.

advantageous Embodiments of the method for increasing the temperature differences are included in claims 7 to 9.

To A preferred embodiment according to claim 7 is to achieve a large short-term temperature difference a high Cutting speed and the narrowest possible cutting beam used.

To Claim 8 is to achieve a large short-term Temperature difference of the material to be separated cooled.

In A preferred embodiment according to claim 10 the intensity and / or cutting speed of the cutting jet depending on the material properties and the Material thickness adjusted so that the cutting jet still through the entire material thickness penetrates, but little to no molten Material ejects or no kerf generated.

Of the Expulsion of molten material or slag becomes very strong limited. In electron and laser beam cutting the ejection can be completely prevented. This will be energy for the Production of a kerf saved, the loss of material through the kerf decreases and the pollution from the ejected Avoided slag.

The conventional kerf is here by a continuous replaced narrow zone with severe cracking. Are still remaining Binding forces in the zone exists, the complete takes place Material separation through additional mechanical effects.

Therefore is proposed according to claim 11, by The cut created two material areas by mutual Tilt separate from each other.

[Examples]

following Let the method be explained by way of example.

A to be cut through sheet metal plate of 10 mm thickness is placed on a shelf for a cutting torch so stored that the Cutting line is not above a support. Also possible is a variant in which the supports each time the cutting jet is lowered for a short time.

One known cutting torch is on both sides of the cutting nozzle each connected to a sonotrode. These are elastic under bias attached. As a result, the sonotrodes in working position on both sides pressed next to the cutting line on the sheet. The sonotrodes are connected to a transducer and generate a frequency of 30 kHz.

Becomes the cutting torch with the cutting jet over the sheet guided, transferred the entrained Sonotrodes simultaneously ultrasonic vibrations on the sheet metal plate in the cutting area.

By the action of the narrow cutting jet creates a narrow molten zone and slag layer in the sheet metal. The initiated ultrasonic vibrations prevent a firm reconnection of the material during the cooling phase. This creates a very narrow, vertical Separating layer to parting line with low slag content. At this Separating layer, the metal plate, z. B. by one-sided lifting, be easily separated.

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• - DD 107226 [0004]

Claims (11)

Process for the thermal separation of materials with a cutting jet, in particular electron beam, in which the cutting jet is guided at a temperature above the melting point of the material while simultaneously introducing mechanical vibrations through the material in order to effect a severing, characterized in that in the cutting region for a short time a maximum temperature difference between the cutting jet and the material is generated in order to effect a localized high internal material tension, and at least in the cutting region of the cutting beam on one or both sides of the cutting line in the material mechanical vibrations are introduced to a parting line, material cracks or a zone of reduced strength produce and at a remaining after the cut residual bond force in the cutting region of the material this is canceled by mechanical action. Method according to claim 1, characterized in that that mechanical vibrations in the ultrasonic range in the material be introduced and the frequency and amplitude in dependence changeable from the material material to be separated and the material structure are. Method according to claim 2, characterized in that that uses oscillations with a frequency of 1 kHz to 50 kHz become. Method according to one of claims 1 to 3, characterized in that the vibrations from a converter via an amplitude transformation piece and a sonotrode directly be directed to the material. Method according to Claim 4, characterized that in the area of the cutting beam the local material carrier temporarily removed from the material to be introduced Not to hinder vibrations. Method according to one of claims 1 to 3, characterized in that on both sides of the cutting line successful introduction of mechanical vibrations in the material the frequency and / or amplitude for each page from each other differ. Method according to claim 1, characterized in that that to achieve a large short-term temperature difference in the cutting area a high cutting speed and a minimal narrow cutting beam is used. Method according to claim 1, characterized in that that to achieve a large short-term temperature difference is cooled in the intersection of the material to be separated. Method according to claim 8, characterized in that that on the material to be separated a cooling liquid is applied. Method according to claim 1, characterized in that that the intensity and / or cutting speed of the Cutting beam depending on the material properties and the material thickness is adjusted so that the cutting steel still through the entire material thickness penetrates, but little to no molten Material ejects or no kerf generated. Method according to one of claims 1 to 10, characterized in that the two generated by the cut Material areas separated by mutual tilting become.