Orbital welding device with simpler handling of the measurement of residual oxygen

Abstract

An orbital welding device (1) for welding two pieces of pipe, the orbital welding device (1) having a welding current source (10) in a welding current source housing (11) and an orbital welding head (20), which is separate from the welding current source housing (11) and is connected to the welding current source (10) by a cable (2), the orbital welding head (20) having a chamber (50) for the use of shielding gas (50) and/or the orbital welding device (1) having a purging device (90) for the use of shielding gas, preferably back-up shielding gas or purge gas, the orbital welding device (1) having an oxygen sensor (40), wherein the oxygen sensor (40) is arranged in or on the welding current source housing (11).

Claims

1. An orbital welding device for welding two pieces of pipe, the orbital welding device comprising: a welding current source in a welding current source housing; an orbital welding head, which is separate from the welding current source housing and is connected to the welding current source by means of a cable, the orbital welding head having a chamber for the use of shielding gas and/or the orbital welding device having a purging device for the use of shielding gas, preferably back-up shielding gas or purge gas; an oxygen sensor arranged in or on the welding current source housing; and a switching device configured to switch over between a first state and at least one further state, wherein in the first state the oxygen sensor is configured to measure the oxygen concentration in the shielding gas before the shielding gas has been introduced into the chamber or at least one of the pieces of pipe to be welded to the connecting point of the pieces of pipe, and in the at least one further state the oxygen sensor is configured to measure the oxygen concentration in the chamber or in the interior of at least one of the pieces of pipe to be welded.

2. The orbital welding device as claimed in claim 1, the orbital welding device being configured to measure, via the oxygen sensor, an oxygen concentration in the chamber.

3. The orbital welding device as claimed in claim 1, the orbital welding device being designed to measure by means of the oxygen sensor an oxygen concentration in the interior of at least one of the pieces of pipe to be welded.

4. The orbital welding device as claimed in claim 3, further comprising a suction intake device configured to intake a sample of the shielding gas from the chamber or from the interior of the at least one of the pieces of pipe to be welded, and conduct the sample to the oxygen sensor, wherein the oxygen sensor is configured to measure the oxygen concentration in the sample.

5. The orbital welding device as claimed in claim 1, the orbital welding device being designed to measure by means of the oxygen sensor an oxygen concentration at various locations simultaneously.

6. The orbital welding device as claimed in claim 1, the orbital welding device being configured to perform the following automatically as part of a welding and measuring program carried out by an electronic computer: switch the switching device into the first state and to measure the oxygen concentration in the shielding gas before the shielding gas has been introduced into the chamber or into at least one of the pieces of pipe to be welded to the connecting point of the pieces of pipe, and after a certain time, switch the switching device into the at least one further state and to measure the oxygen concentration in the chamber or in the interior of at least one of the pieces of pipe to be welded.

7. The orbital welding device as claimed in claim 1, wherein: the orbital welding device comprises a further oxygen sensor configured to measure the oxygen concentration in the chamber or in the interior of at least one of the pieces of pipe to be welded.

8. The orbital welding device as claimed in claim 1, wherein the orbital welding device comprises a memory device and is configured to log, in the memory device, measured residual oxygen measured values of at least one of: the shielding gas before the shielding gas has been introduced into the chamber (50) or via the purging device (90) into at least one of the pieces of pipe to be welded to the connecting point of the pieces of pipe, and/or the shielding gas in the chamber or in the interior of at least one of the pieces of pipe to be welded.

9. The orbital welding device as claimed in claim 3, wherein the oxygen sensor is an optical oxygen sensor and the orbital welding device comprises an optical coupling configured to optically couple the oxygen sensor to at least one of an interior space of the chamber or an interior space of the at least one of the pieces of pipe to be welded, so that the oxygen concentration in the corresponding interior space can be measured via the optical coupling.

10. An orbital welding device for welding two pieces of pipe, the orbital welding device comprising: a welding current source in a welding current source housing; an orbital welding head, which is separate from the welding current source housing and is connected to the welding current source via a cable, wherein at least one of: the orbital welding head having a chamber for the use of shielding gas; or the orbital welding device having a purging device for the use of shielding gas; an oxygen sensor integrated in a component of the orbital welding device, wherein the oxygen sensor is designed to measure an oxygen concentration in the shielding gas before the shielding gas has been introduced into the chamber or to the connecting point of the pieces of pipe; and a switching device configured to switch over between a first state and at least one further state, wherein in the first state the oxygen sensor is configured to measure the oxygen concentration in the shielding gas before the shielding gas has been introduced into the chamber or at least one of the pieces of pipe to be welded to the connecting point of the pieces of pipe, and in the at least one further state the oxygen sensor is configured to measure the oxygen concentration in the chamber or in the interior of at least one of the pieces of pipe to be welded.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Aspects of the invention will now be further illustrated by way of example with reference to drawings, in which:

(2) FIG. 1 shows a first embodiment of a device according to the invention,

(3) FIG. 2 shows, on the basis of the first embodiment, a second embodiment of a device according to the invention,

(4) FIGS. 3A and 3B show, on the basis of the first and second embodiment, a third embodiment of a device according to the invention, wherein 3B shows only a cutout of the embodiment shown in FIG. 3A, with the purging device 90 which is optional in the previous figures no longer being present or shown,

(5) FIG. 4 shows, on the basis of the first and second embodiment, a fourth embodiment of a device according to the invention, with the purging device 90 which is optional in the previous figures no longer being present or shown.

DETAILED DESCRIPTION

(6) A more detailed description of FIG. 1 follows. The configuration is such that the orbital welding device 1 has a welding current source 10 in a welding current source housing 11 and an orbital welding head 20, which is separate from the welding current source housing 11 and is connected to the welding current source 10 by means of a cable 2, the orbital welding head 20 having a shielding gas chamber 50 which is designed to surround and to substantially close off to the outside a welding electrode 23 of the orbital welding head 20 during a welding process, the orbital welding device 1 optionally (at points) having a purging device 90 for the use of shielding gas, preferably back-up shielding gas or purge gas, the orbital welding device 1 having an oxygen sensor 40, wherein the oxygen sensor 40 is arranged in or on the welding current source housing 11.

(7) A more detailed description of FIG. 2 follows. The configuration is such that the orbital welding device 1 has a welding current source 10 in a welding current source housing 11 and an orbital welding head 20, which is separate from the welding current source housing 11 and is connected to the welding current source 10 by means of a cable 2, the orbital welding head 20 having a shielding gas chamber 50 which is designed to surround and to substantially close off to the outside a welding electrode 23 of the orbital welding head 20 during a welding process, the orbital welding device 1 optionally (at points) having a purging device 90 for the use of shielding gas, preferably back-up shielding gas or purging gas, the orbital welding device 1 having an oxygen sensor 40 integrated in another component of the orbital welding device 1, wherein the oxygen sensor 40 is designed to measure an oxygen concentration in the shielding gas before it is conducted into the chamber 50 (or optionally also or alternatively to the connecting point of the pieces of pipe via the purging device 90). In or on the welding current source housing 11, the welding current source housing 11 here has a gas line 61 on which the oxygen sensor 40 is arranged in such a manner that an oxygen concentration in the gas line 61 can be measured, wherein the gas line 61 is designed to connect a gas source 60 (for example a gas cylinder) to the chamber 50 or optionally also or alternatively to the purging device 90, or to be a subsection of said connection. One or more tubes which conduct the shielding gas to the chamber 50 are arranged here along the cable 2. In this example, the same gas as for the shielding gas in the chamber 50 is used as the purging gas.

(8) A more detailed description of FIGS. 3A and 3B follows. In FIG. 3A, the switching device 70 is in the first state, and in the second state in FIG. 3B. The configuration is such that the orbital welding device 1 is designed to measure an oxygen concentration in the chamber 50. The orbital welding device 1 here has a suction intake device 80, by means of which shielding gas can be sucked in from the chamber 50, so that the oxygen concentration therein can be measured. The configuration is such that the orbital welding device 1 has a switching device 70, which is designed to switch over between a first state and a second state, in the first state the oxygen sensor 40 being designed to measure the oxygen concentration in the shielding gas before it is conducted into the chamber 50, and in the second state the oxygen sensor 40 being designed to measure the oxygen concentration in the chamber 50. The switching device here has a switching valve. The configuration is such that the orbital welding device 1 is designed to perform the following automatically as part of a welding and measuring program carried out by an electronic computer, here by the welding current source controllerfirst to switch the switching device 70 into the first state and to measure the oxygen concentration in the shielding gas before it is conducted into the chamber 50, and after a certain time to switch the switching device 70 into the second state and to measure the oxygen concentration in the chamber 50.

(9) A more detailed description of FIG. 4 follows. The configuration is such that the orbital welding device 1 has a further oxygen sensor 40, the further oxygen sensor 40 being designed to measure the oxygen concentration in the chamber 50, differently than in FIGS. 3A and 3B.

REFERENCE SIGNS

(10) 1 Orbital welding device 2 Cable 10 Welding current source 11 Welding current source housing 20 Orbital welding head 23 Welding electrode 40 Oxygen sensor 50 Chamber 60 Gas source 61 Gas line 70 Switching device 80 Suction intake device 90 Purging device 40 Further oxygen sensor