Shielding fluid delivery system and method of protecting welded location by shielding fluid

Abstract

A shielding fluid delivery system for supplying a shielding fluid to a workpiece is provided. The shielding fluid delivery system includes a movement device, and a fluid dispensing device that is movable on the movement device and that is for supplying the shielding fluid to the workpiece when the workpiece is being welded. A method of protecting a welded location of a workpiece is also provided. The method includes: moving a fluid dispensing device on a movement device to the welded location of the workpiece; and supplying a shielding fluid from the fluid dispensing device to the welded location of the workpiece.

Description

SHIELDING FLUID DELIVERY SYSTEM AND METHOD OFPROTECTING WELDED LOCATION BY SHIELDING FLUIDTECHNICAL FIELD

[0001] The present disclosure relates to a fluid delivery system and a method of protecting welded location and in particular to a shielding fluid delivery system and a method of protecting welded location by shielding fluid.BACKGROUND

[0002] In the fabrication of large, long, or complex structures, there is often a need for the welding and joining of plates or pipes in which access is only convenient from one side or location along the joint. During welding, there is a need for protecting the molten metal and surrounding heated base material from reacting with its environment during the joining process; this is the purpose of a “cover” gas or “shielding” gas, to protect a joint from the environment, to prevent a reaction from occurring between them during the joining process, which would result in a weaker joint.

[0003] In the case of pipes, current industry practices for shielding the pipe interior side of the weld, when welding the pipe from the outside, are long, laborious and resource-intensive. The current methodology includes capping a section of pipe and filling it with argon gas to purge the oxygen, until the oxygen concentration is below 100 parts per million (ppm) required to prevent surface oxidation when metals are heated during welding. Achieving this low oxygen concentration throughout a volume of pipe can take many hours and require large amounts of argon, even if only a small volume has been sealed closed to be purged of oxygen, due to the slow displacement of oxygen when a pipe is filled.

[0004] Accordingly, systems and methods that enable effective delivery of a shielding fluid and effective protection of a welded location remain highly desirable.SUMMARY

[0005] In accordance with one aspect of the present disclosure, a shielding fluid delivery system for supplying a shielding fluid to a workpiece is disclosed. The shielding fluid delivery system includes a movement device and a fluid dispensingdevice that is movable on the movement device and that is for supplying the shielding fluid to the workpiece when the workpiece is being welded.

[0006] In accordance with one aspect of the present disclosure, the fluid dispensing device supplies the shielding fluid to an obstructed location of the workpiece that is inaccessible by an operator of the shielding fluid delivery system or a backside region of the workpiece that is opposite to a welded region of the workpiece.

[0007] In accordance with one aspect of the present disclosure, the workpiece forms an enclosure, and the movement device extends into the enclosure such that the fluid dispensing device is movable in the enclosure to supply the shielding fluid.

[0008] In accordance with one aspect of the present disclosure, the shielding fluid delivery system further includes a sensing device that is movable along with the fluid dispensing device and that is for locating a target location of the workpiece based on data collected from the workpiece. The data includes optical data, thermal data, ultrasonic sensing data, capacitive sensing data, electromagnetic field data, position data, gas meter data, laser scanning data, acoustic emission data, or any combination thereof. The fluid dispensing device supplies the shielding fluid to the target location.

[0009] In accordance with one aspect of the present disclosure, the sensing device locates the target location by measuring temperature around the target location.

[0010] In accordance with one aspect of the present disclosure, the movement device includes a rail, a wheel, a track, a cable, a boat, or any combination thereof.

[0011] In accordance with one aspect of the present disclosure, the movement device is pneumatically actuated.

[0012] In accordance with one aspect of the present disclosure, the shielding fluid delivery system further includes a controller device that is programmed or manually operable to control a movement of the fluid dispensing device.

[0013] In accordance with one aspect of the present disclosure, the movement device includes a locking mechanism for locking the fluid dispensing device in placeon the movement device when the fluid dispensing device supplies the shielding fluid to the workpiece.

[0014] In accordance with one aspect of the present disclosure, the locking mechanism include worm gear, band brake, ratchet, cam, pins, or any combination thereof.

[0015] In accordance with one aspect of the present disclosure, the shielding fluid delivery system further includes a monitoring device that is movable along with the fluid dispensing device for monitoring the workpiece when the fluid dispensing device supplies the shielding fluid to the workpiece.

[0016] In accordance with one aspect of the present disclosure, the shielding fluid delivery system further includes a post-processing device that is movable along with the fluid dispensing device for performing post-processing operations to the workpiece after the workpiece is welded, wherein the post-processing operations include cleaning, grinding, coating, surface treatment, or any combination thereof.

[0017] In accordance with one aspect of the present disclosure, the shielding fluid includes an inert fluid, a reactive fluid, or a combination thereof. The inert fluid includes argon gas, helium gas, carbon dioxide gas, nitrogen gas, or any combination thereof.

[0018] In accordance with one aspect of the present disclosure, a method of protecting a welded location of a workpiece is disclosed. The method includes: moving a fluid dispensing device on a movement device to the welded location of the workpiece; and supplying a shielding fluid from the fluid dispensing device to the welded location of the workpiece.

[0019] In accordance with one aspect of the present disclosure, the welded location is a backside region of the workpiece that is opposite to a welded region of the workpiece.

[0020] In accordance with one aspect of the present disclosure, the method further includes, prior to moving the fluid dispensing device along the movement device, locating the welded location of the workpiece by a sensing device that detectsbased on data collected from the workpiece, wherein the data includes optical data, thermal data, ultrasonic sensing data, capacitive sensing data, electromagnetic field data, position data, gas meter data, laser scanning data, acoustic emission data, or any combination thereof.

[0021] In accordance with one aspect of the present disclosure, the welded location of the workpiece is located by comparing the thermal data of the workpiece measured by the sensing device.

[0022] In accordance with one aspect of the present disclosure, locating the welded location of the workpiece includes: measuring temperature data from a first region of the workpiece and a second region of the workpiece; averaging the temperature data from the first region and averaging the temperature data from the second region; and comparing the average temperature of the first and second regions. If the temperature difference between the first and second regions is greater than a predefined threshold, the fluid dispensing device is moved toward the region with higher temperature. If the temperature difference is equal to or smaller than the predefined threshold, the fluid dispensing device is not moved.

[0023] In accordance with one aspect of the present disclosure, the method further includes, after supplying the shielding fluid to the welded location of the workpiece, moving the fluid dispensing device to a next backside region or to a location where the fluid dispensing device is accessible by an operator.

[0024] In accordance with one aspect of the present disclosure, the shielding fluid is supplied to the welded location of the workpiece concurrently with a process of welding the workpiece.

[0025] In accordance with one aspect of the present disclosure, the shielding fluid is further supplied to the welded location before the process of welding the workpiece.

[0026] In accordance with one aspect of the present disclosure, the shielding fluid is further supplied to the welded location after the process of welding the workpiece.

[0027] In accordance with one aspect of the present disclosure, the method further includes, after supplying the shielding fluid to the welded location of the workpiece, performing a non-destructive inspection on the welded location of the workpiece while the fluid dispensing device is still located at the welded location by an inspection device movable along with the fluid dispensing device.BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Further features and advantages of the present disclosure will become apparent from the following detailed description, taken in combination with the appended drawings, in which:

[0029] FIG. 1 is a schematic view of a shielding fluid delivery system used with a workpiece.

[0030] FIG. 2 illustrates a schematic example of the shielding fluid delivery system.

[0031] FIGS. 3 and 4 illustrate another schematic example of the shielding fluid delivery system.

[0032] FIGS. 5 and 6 illustrate a method of detecting and tracking a weld location on the workpiece.

[0033] FIG. 7 illustrates a method of protecting a welded location of the workpiece by a shielding fluid.

[0034] FIG. 8 illustrates an experimental example of a workpiece that is partially protected by the shielding fluid.

[0035] It will be noted that throughout the appended drawings, like features are identified by like reference numerals.DETAILED DESCRIPTION

[0036] Before the present articles, mechanisms, and / or methods are disclosed and described, it is to be understood that the aspects described below are not limited to specific fluid or gas compositions, welded metals, or the joining of specific structures or objects by other means such as adhesives. It is also to be understoodthat the terminology used herein is for the purpose of describing particular aspects only and is not intended to be limiting.

[0037] In this specification and in the claims that follow, reference will be made to a number of terms that shall be defined to have the following meanings.

[0038] It must be noted that, as used in the specification and the appended claims, the singular forms “a,” “an” and “the” include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to a “shielding fluid” may include pure gases or mixtures or fluxes, and “a metal alloy” used as a weld metal or base material, includes mixtures of two or more metal alloys, and the like.

[0039] “Optional” or “optionally” means that the subsequently described event or circumstance can or cannot occur, and that the description includes instances where the event or circumstance occurs and instances where it does not. For example, the phrase “optionally track the position” means that the position of the weld may or may not be moving and tracked when joining in the methods described herein.

[0040] The advantages of the disclosure will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the aspects described below. The advantages described below will be realized and attained by means of the elements and combinations particularly pointed out in the appended claims but the advantages are not limited to what is described in the appended claims. It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive.

[0041] The following embodiments and / or examples are put forth so as to provide those of ordinary skill in the art with a complete disclosure and description of how the device and methods described and claimed herein are made and employed, and are intended to be purely exemplary and are not intended to limit the scope of what the inventors regard as their invention. The values of various specifications are only provided as an example and may depend on the welding application.

[0042] FIG. 1 is a schematic view of a shielding fluid delivery system 100 in accordance with some embodiments of this disclosure. When a joint 201 of aworkpiece 200 is to be welded by using a welding machine 300 with a weld metal (e.g., a metal alloy), a welded region 202 is formed at the joint 201. It may be desirable to supply a shielding fluid to a backside region 204 of the workpiece 200 that is opposite to the welded region 202 for protecting the backside region 204 from oxidation due to the high temperature of welding. This can be achieved by pushing oxygen away from the backside region 204 with the shielding fluid. When the backside region 204 is not easily accessible (e.g., the workpiece 200 being part of a tube, the welded region 202 being located at the outside of the tube, and the backside region 204 being located at the inside of the tube), it might be difficult to efficiently supply the shielding fluid to the backside region 204.

[0043] In this disclosure, the shielding fluid delivery system 100 is provided to achieve the purpose of supplying the shielding fluid to the backside region 204 with limited access. The shielding fluid delivery system 100 includes a movement device 102. The shielding fluid delivery system 100 further includes a base 103 that is movably mounted to the movement device 102, and further includes a fluid dispensing device 104 that is disposed on the base 103 and that can be carried by the base 103 along the movement device 102. The movement device 102 may include a locking mechanism 118 that can hold the base 103 and therefore the fluid dispensing device 104 in place when the fluid dispensing device 104 is positioned for supplying the shielding fluid to the backside region 204. The locking mechanism 118 may lock the base 103 and the fluid dispensing device 104 in place by means of friction, suction, magnetism, mechanical locking, or other suitable mechanisms.

[0044] The movement device 102 allows the fluid dispensing device 104 to be movable on different surfaces, such as flat or curved plane within enclosed or partially enclosed structures. In some embodiments, the movement device 102 may be a rail that extends into the tube and that allows the base 103 to be movably mounted thereon. In some embodiments, the movement device 102 may include multiple wheels or tracks rotatably mounted to the base 103 to allow the base 103 to be movable. In some embodiments, the movement device 102 may be in the form of at least one cable. In some embodiments, at least part of the workpiece 200 may be surrounded by fluid, and the movement device 102 may be in the form of a flying or boating device to allow the base 103 and the fluid dispensing device 104 to travelthrough the fluid to the location of the backside region 204. The movement device 102 allows the shielding fluid delivery system 100 to navigate through structures that are not easily accessible. For example, the movement device 102 is helpful for the fluid dispensing device 104 to be movable in a piping system, where the piping system may include tubes contain sections of different shape, such as straight, curved, inclined, T-joints, varying diameters, etc. After the task for supplying the shielding fluid is completed, the base 103 along with the fluid dispensing device 104 may be moved back to a starting point or an alternate easily accessible location that allows access to the base 103 and the fluid dispensing device 104 for maintenance or other purposes. In some embodiments, the movement device 102 may be pneumatically actuated and may include a pneumatic system with any pressurized gas or air. The pneumatic system may be used to provide rotary motion when the movement device 102 includes wheels or tracks. When the movement device 102 includes pistons, tie rods, or links, the pneumatic system further provides linear actuation to those structures. The pneumatic system may also be assisted by hydraulic intensifier pistons where higher forces are required. The use of pneumatic system to achieve motion and actuation can be achieved using controls of valves through a central manifold that can be compact and integrated in the device structure, which can reduce size and weight of the overall device. In some embodiments, the movement device 102 may be electromechanically actuated and may include an electromechanical motion system which may include rotary motors, linear actuators, servos, stepper motors, etc. The electromechanical motion system may be used to provide rotary motion for driving systems or linear motion of various components, which can coordinate the motion of other components (e.g., the wheels or tracks) to travel through a target structure (e.g., a pipe geometry).

[0045] The shielding fluid being supplied to the backside region 204 can be an inert fluid (e.g., argon gas, helium gas, carbon dioxide gas, nitrogen gas, or any mixtures thereof) for protecting the backside region 204. However, based on different practical applications, the shielding fluid may instead be a reactive fluid, a pure fluid, an adhesive fluid, or other suitable fluids. In some embodiments, based on material properties of joint materials for welding and / or the base material of the workpiece 200, the shielding fluid may be a fluid combination that contains any combination of inertfluid, reactive fluid, pure fluid, adhesive fluid, etc. to achieve desired surface finish, coating, or other effects.

[0046] The fluid dispensing device 104 may include at least one nozzle, at least one orifice, other suitable fluid dispensing mechanism, or any combination thereof, for the holding and directing of a steam of the shielding fluid. The fluid dispensing device104 may be configured according to practical requirements. For example, a ringshaped annular orifice may be used to dispense the shielding fluid around a complete circumference of inside of the workpiece 200. The fluid dispensing device 104 may or may not move independently from the base 103. For example, an actuating mechanism 105 (e.g., a robotic arm) may be provided, where the fluid dispensing device 104 is attached to the actuating mechanism 105, and the actuating mechanism105 provides different operations to the fluid dispensing device 104, such as extension, retraction, rotation, movement, fine position adjustments, etc.

[0047] The shielding fluid delivery system 100 may further include a sensing device 106 for locating the backside region 204, based on technologies, including optical data, thermal data (e.g., thermal imaging 2D camera), thermal proximity, ultrasonic sensing, capacitive sensing, electromagnetic field or Eddy current, position encoders, gas / oxygen meters, laser scanning, acoustic emission, any combinations thereof, or other suitable techniques. For the thermal proximity technique, the shielding fluid delivery system 100 employs an array of thermal sensors (i.e., the sensing device 106) with multiple pixels to detect and track the heat on the interior of the workpiece 200 when the weld is performed on the outer diameter. The thermal proximity technique is latter described with reference to FIGS. 5 and 6. For the optical data technique, the sensing device 106 may include at least one camera that may be used to capture continuous images of inner wall of the workpiece 200, which can be processed in real-time using computer vision algorithms to identify the weld seam and / or edges of the workpiece 200 where the weld is occurring. For the thermal imaging 2D camera technique, as the welding machine 300 is welding or tracking, the weld seam will emit heat. The sensing device 106 may include at least one thermal camera for detecting the emitted heat and for tracking the location of the welding location in real-time, allowing the shielding fluid delivery system 100 to rotate or shift as the weld progresses. For the ultrasonic sensing technique, the welding processmay be monitored and the welded area and base metal of the workpiece 200 may be identified based on structural differences. The sensing device 106 may include at least one ultrasonic sensor for detecting subtle differences in material density or geometry at the weld seam by emitting sound waves and analyzing their reflections from inside of the workpiece 200. As the welder progressed, the shielding fluid delivery system 100 uses these changes in ultrasonic patterns to track and follow the weld path. For the capacitive sensing technique, capacitive sensing could detect changes in the electrical properties (e.g., dielectric constant) of the workpiece 200 caused by the localized heat and the material changes during welding. The sensing device 106 may include at least one capacitive sensor to detect these variations to identify and track the welding location, guiding the shielding fluid delivery system 100 to maintain accurate shielding alignment. For the electromagnetic field or Eddy current technique, as the welder creates an arc on the outside of the workpiece 200, it generates a fluctuating electromagnetic field that penetrates through the wall of the workpiece 200. The sensing device 106 may include at least one electromagnetic and / or current sensor for detecting this field and tracking the movement of the arc, allowing the shielding fluid delivery system 100 to follow the weld path and maintain proper gas shielding. The sensing device 106 may also supply alternating magnetic fields to generate Eddy currents which may be used to find the joint location before welding and position the shielding fluid delivery system 100 to the correct point. For the position encoder technique, the sensing device 106 may include at least one position encoder (which may be attached to a rotating arm) to track angular movement around the workpiece 200 with high precision. By correlating the encoder’s position data with the known starting point of the weld and using estimated average speed of the welder, the sensing device 106 can follow the progress of the welding machine 300 and follow the shielding gas aligned with the welding location. For the gas / oxygen meter technique, the sensing device 106 may include at least one gas or oxygen meter for detecting changes in oxygen concentration inside the workpiece 200 caused by the external welding arc, where increased heat may cause slight variations in gas level. These fluctuations allow the shielding fluid delivery system 100 to estimate the weld location and guide the system to maintain shielding. For the laser scanning technique, the sensing device 106 may include at least one laser scanner, which is pointed towards the inner surface of the workpiece 200 to create a profile of the inner surfaceof the workpiece 200. The welding location would show as a deviation in the profile, which the shielding fluid delivery system 100 can track. For the acoustic emission technique, the sensing device 106 may include at least one acoustic sensor for detecting high-frequency sound waves naturally generated by the welding process (e.g., arc strikes) or material stress changes. The shielding fluid delivery system 100 can use these acoustic signals to pinpoint the active weld location to guide the shielding fluid delivery system 100 to follow and shield the weld in real time.

[0048] The sensing device 106 may be mounted to the base 103 and movable with the fluid dispensing device 104, allowing precise positioning of the fluid dispensing device 104 relative to the backside region 204. The shielding fluid delivery system 100 may optionally follow a feature on the components such as the base material or joining materials, or a feature of the joining process, such as any indicator of a gap to be joined, a weld pool, a weld metal, any spatter or emissions, or any distortions in the work piece 200. In some embodiments, the shielding fluid delivery system 100 may follow physical or visible markers that have been added, that may be detected (e.g., by the sensing device 106) and that can indicate the intended path of the joint formation during the joining operation. The sensing device 106 may also optionally track the position of the weld.

[0049] The shielding fluid delivery system 100 may further include a controller device 108 that can be disposed on the base 103 or can be incorporated in the base 103, that can be attached to the fluid dispensing device 104, or that can be located at other suitable positions. The controller device 108 incorporates an algorithm to center and track the fluid dispensing device 104 and maintain the position of the fluid dispensing device 104 relative to the backside region 204 as the joining is performed on a path along or between one or more workpiece 200. In some embodiments, the algorithm may control the movement of the fluid dispensing device 104 based on data collected by the sensing device 106. Human intervention may be present during the automated control of the fluid dispensing device 104 if needed. In some embodiments, the controller device 108 may be programmed to be operable by an operator at a more accessible location to control the fluid dispensing device 104. The position of the fluid dispensing device 104 may alternatively be controlled manually when needed. In some embodiments, remote communication between the operator and theshielding fluid delivery system 100 may be achieved using wireless communication or other suitable technologies.

[0050] The shielding fluid delivery system 100 may further include a monitoring device 110 (e.g., at least one camera) that may be optionally used to monitor the weld quality and inspect the completed weld. The monitoring device 110 may also provide real-time monitoring, or media such as pictures and videos, that can allow for later inspection. In some embodiments, the sensing device 106 and the monitoring device 110 may be combined as a single device that is compact and multifunctional to perform any or all of the abovementioned functions.

[0051] The shielding fluid delivery system 100 may further include a postprocessing device 112 to perform post-process operations on the weld and / or the backside region 204, thereby further improving the quality of the weld. The postprocess operations may be cleaning, grinding, coating, surface treatment, or other suitable operations.

[0052] The shielding fluid delivery system 100 may further include an inspection device 114 that performs inspections (e.g., non-destructive inspections) of the weld and / or the backside region 204.

[0053] In some embodiments, when the fluid dispensing device 104 is configured to supply the adhesive fluid to complete the joint 201 of the workpiece 200, the shielding fluid delivery system 100 may further include a curing device 116 that serves as heat or light sources to provide activation for curing the adhesive fluid.

[0054] The shielding fluid delivery system 100 can travel through the interior of the workpiece 200 which may be heated up (e.g., to around 250°C) during the welding process for prolonged periods without degradation of the device operation or structure. This may be achieved through the use of temperature resistance materials. In some embodiments, the shielding fluid delivery system 100 may further include a protection fluid mechanism 117 that is operable to supply protection fluid (e.g., a cooling fluid in a form of gas or liquid) to sensitive components of the shielding fluid delivery system 100. This ensures that the shielding fluid delivery system 100 may be used in various process types (e.g., gas tungsten arc welding, gas metal arc welding, submerged arc welding, etc.) which mav Generate a hioh amount of heat or requirepre-heating of the workpiece 200, and may be used for the workpiece 200 made of different materials (e.g., carbon steel, chromium alloyed steel, etc.).

[0055] The shielding fluid delivery system 100 also has protection from outside contaminants (e.g., dust, debris, metal chips, grinding particles, moisture, etc.) which may be generated in a welding environment. This may be accomplished by integrating all critical components in sealed housings that are closed to the surrounding environment.

[0056] FIG. 2 illustrates a schematic example of the shielding fluid delivery system 100 working with the workpiece 200. Only a part of the elements of this disclosure is shown and described in FIG. 2 for simplicity of illustration. In the example of FIG. 2, the workpiece 200 is a pipeline and the joint 201 is to be welded. The shielding fluid delivery system 100 is inserted into the workpiece 200 to reach the backside region 204 (see FIG. 1) of the workpiece 200. In the example of FIG. 2, the movement device 102 includes three wheels 119 that allows the base 103, the fluid dispensing device 104, and the sensing device 106 to smoothly move inside the workpiece 200. The base 103 may include multiple sections (e.g., two sections are shown in FIG. 2 as indicated by two arrows), where at least one section is operable to rotate (e.g., as shown by arrow (A) in FIG. 2) the fluid dispensing device 104 and the sensing device 106 to adjust their position relative to the backside region 204 when needed. A fluid inlet 120 is also shown in FIG. 2, where one end of the fluid inlet 120 is connected to the base 103 which ultimately lead to the fluid dispensing device 104 and the other end is connected to a shielding fluid source (e.g., a tank 500), such that the shielding fluid is provided from the shielding fluid source to the fluid dispensing device 104, which in turn supplies the shielding fluid to the backside region 204. In another configuration, the fluid inlet 120 may be directly connected to the fluid dispensing device 104 without going through the base 103. In yet another configuration, the shielding fluid may be preloaded in the fluid dispensing device 104, and then brought to the backside region 204 by the fluid dispensing device 104.

[0057] FIGS. 3 and 4 illustrate another schematic example of the shielding fluid delivery system 100 working with the workpiece 200. In this example, the movement device 102 includes a plurality of frames 121 that are pivotally connected to the base 103, and a plurality of continuous tracks 123 wound on the frames 121. Themovement device 102 further includes a resilient member 124 that is biased against the frames 121 so that the continuous tracks 123 are maintained in position away from the base 103. In FIG. 4, the shielding fluid delivery system 100 is illustrated to include two sensing devices 106. However, the number of the sensing devices 106 may be changed according to practical requirements. In FIG, 4, the shielding fluid delivery system 100 also includes a distance meter 109 (e.g., a laser distance measurer) that allows measurement of distance between the shielding fluid delivery system 100 and a target (e.g., the backside region 204 of the workpiece 200). In FIG. 4, the fluid dispensing device 104 is illustrated as a flat nozzle that is capable of supplying a laminar flow for efficient use and delivery of the shielding fluid.

[0058] In some embodiments, the movement device 102 may allow the shielding fluid delivery system 100 to climb on a slanted or vertical surface of the workpiece 200. For example, the wheels 119 (see FIG. 2) or the continuous tracks 123 (FIG. 3) may climb on a slanted or vertical surface though friction, vacuum suction, adhesion, etc. The wheels or the continuous tracks may include mechanical locking systems (which may be electromechanically actuated), including self-locking via worm gear, band brake, ratchet, cam, pins, any combination thereof, or other suitable mechanisms, so that the friction attachment of the shielding fluid delivery system 100 to the workpiece 200 is increased and the shielding fluid delivery system 100 may therefore properly stay in desired locations. In some embodiments, secondary increase of pneumatic forces may be provided to the movement device 102 to enhance the locking mechanism. This will prevent any slow creep or sliding of the shielding fluid delivery system 100 during the shielding has delivery operation.

[0059] FIGS. 5 and 6 an example of a method of using the sensing device 106 for detecting and tracking the position of a weld location from the back side of the molten weld pool (e.g., from the backside region 204 (see FIG. 1)). In the method for detecting and tracking the position of a weld location, an electronic measurement is continuously made of the relative temperature data from multiple pixels and divides the array into two regions. The shielding fluid delivery system 100 then calculates the average temperatures from a first half of the pixels and a second half of the pixels, followed by comparing the average temperature of the first half and the average temperature of the second half. If the temperature difference between the two halvesexceeds a predefined threshold, the shielding fluid delivery system 100 adjusts its position by rotating toward the higher pixel values. If the difference is within the threshold, it maintains its position and may briefly pause before repeating the process. This feedback mechanism may enable real-time tracking and following of the heat source based on thermal gradients across the sensor array. Specific examples of the tracking mechanism are described below with reference to FIGS. 5 and 6.

[0060] It should be noted that regions P0-P7 and steps (1)-(9) are merely numbered for illustration purposes, the numerals do not necessarily imply the sequence of the regions and steps, and the order of the regions or steps may be changed according to practice requirements. In step (1 ), it is determined if an automatic mode of the sensing device 106 is enabled. If the automatic mode is not enabled, the sensing device 106 does not automatically perform detecting and tracking operations. If the automatic mode is enabled, the method proceeds to step (2), where the sensing device 106 retrieves temperature vectors. An example is shown in FIG. 5, where the sensing device 106 scans the regions P0-P7 along the X- direction to collect temperature readings of those regions. The Y-direction may indicate the width of each scan. It should be noted that the direction and location of scanning is not limited to what is shown in FIG. 5, and may be changed according to practice requirements. It should also be noted that the number of regions being scanned is not limited to eight, and may be changed according to practical requirements. The method then proceeds to step (3), where the temperature data of regions P0-P3 (i.e. , a first half of the regions) are averaged, and the temperature data of regions P4-P7 (i.e., a second half of the regions) are averaged. Then, in step (4), it is determined if the average of the first half of the regions is greater than the average of the second half of the regions by a certain value (e.g., two degrees Celsius). If the average of the first half of the regions is greater than the average of the second half of the regions by the certain value, than the method proceeds to step (5), where the sensing device 106 along with the fluid dispensing device 104 (see FIG. 1 ) are moved towards the first half of the regions (i.e., regions P0-P3). Afterwards, the method proceeds to step (9), where the sensing device 106 waits for a certain time (e.g., 10 milliseconds) and then the method returns to step (1 ). If the average of the first half of the regions is not greater than the average of the second half of the regions by the certain value, then the method proceeds to step (6), where it is determined if theaverage of the second half of the regions is greater than the average of the first half of the regions by the certain value. If the average of the second half of the regions is greater than the average of the first half of the regions by the certain value, than the method proceeds to step (7), where the sensing device 106 along with the fluid dispensing device 104 are moved towards the second half of the regions (i.e. , regions P4-P7). Afterwards, the method proceeds to step (9), where the sensing device 106 waits for the certain time and then the method returns to step (1 ). If the average of the second half of the regions is not greater than the average of the first half of the regions by the certain value, than the method proceeds to step (8), where it is confirmed if the temperature difference between the first and second halves of the regions is not greater than the certain value. The method may proceed to step (9), where the sensing device 106 waits for the certain time and then the method returns to step (1 ). Alternatively, the method may come to an end. This method allows an automatic use of the sensing device 106 for detecting and tracking the position of the weld location from the back side of the molten weld pool (e.g., from the backside region 204).

[0061] FIG. 7, with reference to FIG. 1 , illustrates a method 400 of protecting a welded location of the workpiece 200 by the shielding fluid. It should be noted that steps 402-408 are merely numbered for illustration purposes, and the order of the steps may be changed. According to practical requirements, at least one of the steps may be omitted from the method, or at least one of additional steps may be added to the method.

[0062] In step 402, the backside region 204 is located, for example, by the sensing device 106 and with the abovementioned mechanisms. In step 404, after the backside region 204 is located, the fluid dispensing device 104 is moved to the backside region 204. It should be noted that the expression “to the backside region 204” may mean directly located at the backside region 204, or may be close enough to the backside region 204 for the supply of the shielding fluid. In some embodiments, step 402 may be omitted when the location is obvious or known by the operator of the shielding fluid delivery system 100, and the operator is able to control or manually move the shielding fluid delivery system 100 to the backside region 204. In step 406, the shielding fluid is supplied by the fluid dispensing device 104 to the backside region 204. It should be noted that the shielding fluid may be supplied to the backside region204 when the workpiece 200 is being welded (i.e., supplying the shielding fluid concurrently with the welding process). In some embodiments, the shielding fluid may be supplied to the backside region 204 shortly before and during the welding process to ensure that the backside region 204 is fully protected by the shielding fluid. In some embodiments, the shielding fluid may continuous be supplied to the backside region 204 for a certain period of time after the welding process to ensure that the backside region 204 is protected even after the welding process as there might be residual heat from the welding process. The length of the certain period of time may depend on practical requirements, such as the material of the workpiece 200, the thickness of the workpiece 200, the condition of the backside region 204, the temperature of the welding process, the atmospheric environment of the backside region 204, etc. Then, in step 408, the fluid dispensing device 104 is moved away from the backside region 204. In some embodiments of step 408, the fluid dispensing device 104 may be moved to a next backside region (when the location of the next backside region is known or is located) for supplying the shielding fluid to the next backside region. In some embodiments of step 408, the fluid dispensing device 104 may be moved to a starting point or an alternate easily accessible location that allows access to the fluid dispensing device 104 for maintenance or other purposes.

[0063] FIG. 8 shows an experimental example, where a part (i.e., the shielded region (S)) of the backside region 204 is protected by the shielding fluid during welding and another part (i.e., the unshielded region (U)) of the backside region 204 is not protected by the shielding fluid during welding. It is clear that the shielded region (S) has significantly less oxidation than the unshielded region (U), demonstrating the significance of the shielding fluid delivery system 100 of this disclosure.

[0064] The device and method described herein are advantageous because they provide significant time, cost and resource savings compared to traditional device and methods. A conservative estimate of the time required to weld a 42” diameter pipe for a typical transmission pipeline would be around 6.9 hours via traditional methods. In contrast, with the localized fluid delivery solution according to this disclosure, the time required would just be the set-up time as well as the time to weld. For the case of a 42” diameter pipe, this is estimated to total to 1 .4 hours, such that using a localized solution would reduce the time required by 79%. A local solution,that would only be consuming argon for the time that it takes to complete the weld at 80 L / min (169.5 cubic feet / hour) would only require 152.5 cubic feet, which is a reduction of 36.4% in shielding fluid required.

[0065] This disclosure provides advantages including effective supplying shielding fluid to an inaccessible region (e.g., the backside region 204) to improve weld quality. In addition, traditional configuration needs to set up an appropriate environment for the weld before the welding is conducted, this disclosure allows the shielding fluid to be supplied to the backside region immediately before or only during (i.e., simultaneously welding and supplying shielding fluid) welding is taking place, thereby achieving a more efficient use of time and shielding fluid. This disclosure also allows inspection equipment to monitor or observe the backside region 204, which is often located at inaccessible locations by traditional system.

[0066] It would be appreciated by one of ordinary skill in the art that the system and components shown in the figures may include components not shown in the drawings. For simplicity and clarity of the illustration, elements in the figures are not necessarily to scale and are only schematic. It will be apparent to persons skilled in the art that a number of variations and modifications can be made without departing from the scope of the invention as described herein.

[0067] It is contemplated that any part of any aspect or embodiment discussed in this specification can be implemented or combined with any part of any other aspect or embodiment discussed in this specification.

[0068] It should be recognized that features and aspects of the various examples provided above can be combined into further examples that also fall within the scope of the present disclosure.

[0069] When used in this specification and claims, the terms "comprises" and "comprising" and variations thereof mean that the specified features, steps, or components are included. The terms are not to be interpreted to exclude the presence of other features, steps, or components.

[0070] The invention may also broadly consist in the parts, elements, steps, examples and / or features referred to or indicated in the specification individually orcollectively in any and all combinations of two or more said parts, elements, steps, examples, and / or features. In particular, one or more features in any of the embodiments described herein may be combined with one or more features from any other embodiment(s) described herein.

Claims

CLAIMS:1 . A shielding fluid delivery system for supplying a shielding fluid to a workpiece, the shielding fluid delivery system comprising: a movement device; and a fluid dispensing device that is movable on the movement device and that is for supplying the shielding fluid to the workpiece when the workpiece is being welded.

2. The shielding fluid delivery system of claim 1 , wherein the fluid dispensing device supplies the shielding fluid to an obstructed location of the workpiece that is inaccessible by an operator of the shielding fluid delivery system or a backside region of the workpiece that is opposite to a welded region of the workpiece.

3. The shielding fluid delivery system of claim 1 , wherein the workpiece forms an enclosure, and the movement device extends into the enclosure such that the fluid dispensing device is movable in the enclosure to supply the shielding fluid.

4. The shielding fluid delivery system of any one of claims 1 to 3, further comprising a sensing device that is movable along with the fluid dispensing device and that is for locating a target location of the workpiece based on data collected from the workpiece, wherein the data includes optical data, thermal data, ultrasonic sensing data, capacitive sensing data, electromagnetic field data, position data, gas meter data, laser scanning data, acoustic emission data, or any combination thereof, and wherein the fluid dispensing device supplies the shielding fluid to the target location.

5. The shielding fluid delivery system of claim 4, wherein the sensing device locates the target location by measuring temperature around the target location.

6. The shielding fluid delivery system of any one of claims 1 to 5, wherein the movement device includes a rail, a wheel, a track, a cable, a boat, or any combination thereof.

7. The shielding fluid delivery system of claim 6, wherein the movement device is pneumatically actuated.

8. The shielding fluid delivery system of any one of claims 1 to 7, further comprising a controller device that is programmed or manually operable to control a movement of the fluid dispensing device.

9. The shielding fluid delivery system of any one of claims 1 to 8, wherein the movement device includes a locking mechanism for locking the fluid dispensing device in place on the movement device when the fluid dispensing device supplies the shielding fluid to the workpiece.

10. The shielding fluid delivery system of claim 9, wherein the locking mechanism include worm gear, band brake, ratchet, cam, pins, or any combination thereof.

11. The shielding fluid delivery system of any one of claims 1 to 10, further comprising a monitoring device that is movable along with the fluid dispensing device for monitoring the workpiece when the fluid dispensing device supplies the shielding fluid to the workpiece.

12. The shielding fluid delivery system of any one of claims 1 to 11 , further comprising a post-processing device that is movable along with the fluid dispensing device for performing post-processing operations to the workpiece after the workpiece is welded, wherein the post-processing operations include cleaning, grinding, coating, surface treatment, or any combination thereof.

13. The shielding fluid delivery system of any one of claims 1 to 12, wherein the shielding fluid includes an inert fluid, a reactive fluid, or a combination thereof, wherein the inert fluid includes argon gas, helium gas, carbon dioxide gas, nitrogen gas, or any combination thereof.

14. A method of protecting a welded location of a workpiece, the method comprising: moving a fluid dispensing device on a movement device to the welded location of the workpiece; and supplying a shielding fluid from the fluid dispensing device to the welded location of the workpiece.

15. The method of claim 14, wherein the welded location is a backside region of the workpiece that is opposite to a welded region of the workpiece.

16. The method of claims 14 or 15, further comprising, prior to moving the fluid dispensing device along the movement device, locating the welded location of the workpiece by a sensing device that detects based on data collected from the workpiece, wherein the data includes optical data, thermal data, ultrasonic sensing data, capacitive sensing data, electromagnetic field data, position data, gas meter data, laser scanning data, acoustic emission data, or any combination thereof.

17. The method of claim 14, wherein, the welded location of the workpiece is located by comparing the thermal data of the workpiece measured by the sensing device.

18. The method of claim 17, wherein locating the welded location of the workpiece includes: measuring temperature data from a first region of the workpiece and a second region of the workpiece; averaging the temperature data from the first region and averaging the temperature data from the second region; and comparing the average temperature of the first and second regions, wherein if the temperature difference between the first and second regions is greater than a predefined threshold, the fluid dispensing device is moved toward the region with higher temperature, and wherein if the temperaturedifference is equal to or smaller than the predefined threshold, the fluid dispensing device is not moved.

19. The method of any one of claims 14 to 18, further comprising, after supplying the shielding fluid to the welded location of the workpiece, moving the fluid dispensing device to a next backside region or to a location where the fluid dispensing device is accessible by an operator.

20. The method of any one of claims 14 to 19, wherein the shielding fluid is supplied to the welded location of the workpiece concurrently with a process of welding the workpiece. 21 . The method of claim 20, wherein the shielding fluid is further supplied to the welded location before the process of welding the workpiece.

22. The method of claims 20 or 21 , wherein the shielding fluid is further supplied to the welded location after the process of welding the workpiece.

23. The method of any one of claims 14 to 22, further comprising, after supplying the shielding fluid to the welded location of the workpiece, performing a nondestructive inspection on the welded location of the workpiece while the fluid dispensing device is still located at the welded location by an inspection device movable along with the fluid dispensing device.

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