Short circuit welding method

Patent metadata

Field	Value
Publication number	US-10661371-B2
Application number	US-201716331645-A
Country	US
Kind code	B2
Filing date	Sep 8, 2017
Priority date	Sep 9, 2016
Publication date	May 26, 2020
Grant date	May 26, 2020

Abstract

A short circuit welding method with successive welding cycles with a respective arc phase and short circuit phase includes controlling at least the welding parameters welding current and feed speed of a melting electrode and feeding the electrode toward of a workpiece at a predetermined forward final speed at least during part of the arc phase and away from the workpiece at a predetermined rearward final speed at least during part of the short circuit phase. A device carries out this method. A change in the feed speed and a rearward final speed are predetermined and a welding current is controlled to complete the short circuit phase after reaching the rearward final speed and after 3 ms at the latest and repeat every 8 ms at the latest. The welding parameters are controlled such that the welding cycle duration≤8 ms, resulting in a welding frequency≥125 Hz.

First claim

The invention claimed is:

1. A short circuit welding method with successive welding cycles having each an arc phase and a short circuit phase, the method comprising the steps of:
controlling or setting at least the welding parameters, welding current and feed speed of a melting electrode;
feeding the electrode in the direction of a workpiece to be machined at a predetermined forward final speed at least during a part of the arc phase;
feeding the electrode away from the workpiece at a predetermined rearward final speed at least during a part of the short circuit phase;
predetermining a change in the feed speed and a rearward final speed and controlling or setting the welding current;
completing the short circuit phase after reaching the rearward final speed and after 3 ms at the latest;
repeating the short circuit phase at the latest every 8 ms;
reducing the forward final speed of the electrode before the start of the short circuit phase; and
controlling the welding parameters in such a way that the duration of a welding cycle is less than or equal to 8 ms, resulting in a welding frequency of greater than or equal to 125 Hz.

2. The short circuit welding method according to claim 1 , further comprising the step of feeding the electrode at the forward final speed during the arc phase which corresponds to the rearward final speed during the short circuit phase.

3. The short circuit welding method according to claim 1 , further comprising the step of feeding the electrode at the forward final speed during the arc phase and the rearward final speed during the short circuit phase in the range between 30 m/min and 60 m/min.

4. The short circuit welding method according to claim 1 , further comprising the step of regulating the welding parameters such that the duration of the welding cycle is less than or equal to 6.6 ms, resulting in a welding frequency of 150 Hz or greater.

5. The short circuit welding method according to claim 1 , further comprising the step of controlling the welding parameters such that the duration of the arc phase is at least twice as long as the duration of the short circuit phase.

6. The short circuit welding method according to claim 1 , further comprising the step of controlling the welding current in the form of a current pulse, the duration of which is determined in the short circuit phase as a function of the imminent end of the short circuit phase.

7. The short circuit welding method according to claim 1 , further comprising the steps of first keeping the welding current constant at a predetermined value over a predetermined duration during the short circuit phase and then reducing the welding current.

8. The short circuit welding method according to claim 7 , further comprising the step of keeping the welding current constant during the short circuit phase at the predetermined value over a duration of at least 1 ms.

9. The short circuit welding method according to claim 1 , further comprising the step of predetermining the change in the feed speed in a range between 30000 m/min/s and 60000 m/min/s.

Assignees

• Fronius Int Gmbh

Inventors

• Waldhoer Andreas
• Artelsmair Josef
• Mayer Manuel

Classifications

• B23K9/0953

  using computing means · CPC title

• B23K9/092 Primary

  characterised by the shape of the pulses produced · CPC title

• B23K9/0737 Primary

  Stabilising of the arc position · CPC title

• B23K9/091

  characterised by the circuits · CPC title

• B23K9/1056

  by using digital means (B23K9/1068 takes precedence) · CPC title