Method and Apparatus for Automated Welding

• US 20110210110A1
• Filed: 02/24/2011
• Published: 09/01/2011
• Est. Priority Date: 02/26/2010
• Status: Abandoned Application

• Current Assignee: Brian Riddle, Jacob Coots, Jorge Tarajano, Stephen Dearman
• Original Assignee: Brian Riddle, Jacob Coots, Jorge Tarajano, Stephen Dearman
• Inventors: Coots, Jacob, Tarajano, Jorge, Riddle, Brian, Dearman, Stephen
• Application Number:
  US13/034,310
• Publication Number:
  US 20110210110A1
• Time in Patent Office: Days
• US Class Current: 219/137.R
• CPC Class Codes: B23K 2101/12 Vessels
• CPC Class Codes: B23K 37/0282 Carriages forming part of a welding unit
• CPC Class Codes: B23K 9/0206 of horizontal seams in assembling vertical plates, a welding unit being adapted to travel along the upper horizontal edge of the plates

Abstract

A method of welding plate joints during construction or repair of a structure. The method includes the steps of: (a) positioning a series of plates forming a structure component next to one another to form a series of joints for welding; (b) positioning a welding system on or adjacent to the series of plates, the welding system including a platform with an articulating welding arm positioned thereon, wherein the articulating arm comprises a welding head and a joint sensor; (c) directing the articulating arm with a controller to detect a first joint with the joint sensor; (d) beginning to weld the first joint; (e) adjusting the position of the welding head to track the weld joint based on data from the joint sensor; and (f) repositioning the articulating arm and positioning the welding head adjacent a second weld joint to begin welding the second joint.

Claims

1. A method of welding plate joints during construction or repair of a storage tank, the method comprising the steps of:

a. positioning a series of plates forming a tank component next to one another to form a series of joints for welding;

b. positioning a welding system on or adjacent to the series of plates, the welding system including a platform with an articulating welding arm positioned thereon, wherein the articulating arm comprises (i) a rotating base and at least two arm segments connected at a pivot point and extending from the rotating base, (ii) a welding head, and (iii) a joint sensor;

c. directing the articulating arm with a controller to detect a first joint with the joint sensor;

d. beginning to weld the first joint;

e. adjusting the position of the welding head to track the weld joint based on data from the joint sensor;

f. upon reaching a weld termination condition, to cease welding;

g. rotating the base and positioning the welding head adjacent a second weld joint;

h. repeating steps (d) through (f); and

i. maintaining the platform in a substantially stationary position while performing steps (d) through (f).

2. The method according to claim 1, wherein the tank component is at least one of a tank floor, a tank roof, or a tank sidewall.

3. The method according to claim 1, further comprising maintaining the platform in a substantially stationary position while performing steps (d) through (h).

4. The method according to claim 1, wherein the platform comprises a stationary platform with stabilizing legs.

5. The method according to claim 1, wherein prior to the welding step, performing the step of detecting with the joint sensor multiple locations of the welding joint and recording the locations.

6. The method according to claim 1, wherein prior to the welding step, performing the step of engaging releasable stabilizing legs into contact with the tank plates.

7. The method according to claim 6, wherein the stabilizing legs comprise electro-mechanically activated legs and/or vacuum activated legs.

8. The method according to claim 1, where in addition to performing a welding operation, the articulating arm performs at least one of a buffing, a grinding, or a cutting operation.

9. The method according to claim 1, wherein the controller reads from memory a coordinate system corresponding to the series of plates and positions the articulating arm base on the coordinate system.

10. The method according to claim 1, wherein the controller positions the articulating arm at a first boundary point and moves the articulating arm in a first direction until the weld joint is detected.

11. The method according to claim 10, wherein the controller stops the movement of the articulating arm at a second boundary point if no weld joint is detected.

12. The method according to claim 10, wherein the systems performs the steps of determining a first and second point on the weld joint with the joint sensor and calculates a weld trajectory therefrom.

13. The method according to claim 12, wherein the system determines a further stop point and a further start point along the weld trajectory.

14. The method according to claim 13, wherein the start point and stop point are approximately the maximum reach of the articulating arm along the weld trajectory.

15. The method according to claim 13, wherein the start point and stop point are approximately set by contemporaneous user interface control.

16. The method according to claim 12, wherein the system adjusts weld torch path along the weld trajectory during the welding step base upon through-arc sensing.

17. The method according to claim 1, wherein the articulating arm terminates in a rotating bracket.

18. The method according to claim 10, wherein the platform is moved with a pallet truck.

19. The method according to claim 1, wherein a light marker is projected from the platform and the step of positioning the system includes aligning the light marker with a weld joint.

20. The method according to claim 19, wherein the light marker comprises a laser beam projected as a line onto the plates.

21. The method according to claim 1, further comprising the step of positioning at least one magnet approximately along the weld joint to indicate an approximate stop point of a welding operation.

22. The method according to claim 1, wherein the stabilizing legs include suction cups attached to the platform and the suction cups are actuated after positioning of the platform.

23. An automated welding system comprising:

a. a welding platform;

b. a self-positioning arm mounted on the platform, the self-positioning arm including a rotating base and at least two arm segments connected at a pivot point;

c. a welding machine including a welding head attached to the self-positioning arm;

d. a weld joint sensor;

e. a controller communicating with the self-positioning arm, the joint sensor, and the welding machine, the controller programmed to execute the following steps;

i) detect the position of a weld joint with the joint sensor;

ii) position the welding head adjacent to the weld joint and begin welding the joint at a weld head velocity which is different from a platform velocity;

iii) adjust the position of the welding head to track the weld joint; and

iv) upon reaching a weld termination condition, to cease welding.

24. The automated welding system according to claim 23, wherein the welding platform is a first platform including the self-positioning arm and the system comprises a second platform including the welding machine.

25. The automated welding system according to claim 24, wherein the first platform includes a flux delivery and recovery system comprising a delivery hose and a recovery hose attached to the self-positioning arm.

26. The automated welding system according to claim 23, wherein the platform comprises a plurality of stabilizing legs and each stabilizing leg comprises at least one flexible inverted cup and a vacuum passage communicating with the cup.

27. The automated welding system according to claim 23, wherein the joint sensor comprises a mechanical sensing device.

28. The automated welding system according to claim 23, wherein a laser projector on the platform projects a laser line a know distance from the platform, allowing the system to approximate the location of weld joints on a standard sized plate on which the platform is position.