CN207223255U - The automatic welding device of large and medium-sized bend pipe girth joint peculiar to vessel - Google Patents

The automatic welding device of large and medium-sized bend pipe girth joint peculiar to vessel Download PDF

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Publication number
CN207223255U
CN207223255U CN201721095636.4U CN201721095636U CN207223255U CN 207223255 U CN207223255 U CN 207223255U CN 201721095636 U CN201721095636 U CN 201721095636U CN 207223255 U CN207223255 U CN 207223255U
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welding
bend pipe
welded
driving device
around
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Inventor
刘志军
毕齐林
唐振宇
徐虎
许智敏
陈新恩
黄淼嘉
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Guangzhou Maritime University
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Guangzhou Maritime University
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Abstract

The utility model discloses the automatic welding device of large and medium-sized bend pipe girth joint peculiar to vessel, including motion controller, image processor, weld joint tracking module, slide, multiple positioners and the multiple position sensors being arranged on slide, bend pipe to be welded is installed on positioner, and slide unit, slide and multiple position sensors are used for realization welding robot and the matching of positioner position where bend pipe to be welded;Weld joint tracking module captures the variable quantity that bend pipe posture to be welded and weld seam are occurred in the welding position of bend pipe to be welded, welding process, and send motion controller to after image processor is handled, hunting frequency, the amplitude of welding robot movement locus and swinging arc device are controlled by motion controller.The utility model realizes positioner and mobile welding robot Collaborative Control, and welding torch position can accurately be directed at elbow pipe welding position in real time, and welding efficiency is high, and quality is easily guaranteed that.

Description

The automatic welding device of large and medium-sized bend pipe girth joint peculiar to vessel
Technical field
It the utility model is related to welding field, more particularly to a kind of automatic welding dress of large and medium-sized bend pipe girth joint peculiar to vessel Put.
Background technology
In the pipeline manufacturing process such as ship, nuclear power, by pipe fitting of different shapes (such as straight tube, bend pipe) with different postures Assembly is carried out, obtains baroque pipeline, the conveying for the energy, gas etc..Bend pipe in the fabrication process, exists small quantities of The features such as amount, multi items, scale topography be different.
Producer more at present employs the mode of manual welding, its welding efficiency is relatively low, and welding quality homogeneity is relatively low, Cost of labor is higher.In order to accelerate welding efficiency, the manufacturing enterprise such as labor strength, some large-scale ship, nuclear powers is reduced The mode for employing positioner and being manually combined, the welding manner weld to be semi-automatic, and welding quality is to craftsmanship's Dependence is higher, and radiation, flue dust in welding process etc. drastically influence the physical and mental health of worker.
In order to further reduce injury of the welding surroundings to worker during large and medium-sized elbow pipe welding, welding efficiency is improved, Welding quality and homogeneity are lifted, some domestic and international scientific research institutions, colleges and universities' phase sequence have developed swing arm welding robot and displacement The welding system that machine is combined, such system have obtained certain application in the straight tube welding of standardization.It is different in model During elbow pipe welding, on the one hand, each positioner can only adapt to the welding of a serial bend pipe, therefore each positioner Utilization rate is not high, if each positioner is equipped with corresponding swing arm robot system, cost is higher, and input and output are compared It is low;On the other hand, the welding system that the existing swing arm robot based on off-line programing is combined with positioner, was being welded Need to work out corresponding code for the pattern of different pipe fittings in journey and previewed, programming personnel's workload is larger and welding is imitated Rate is not still high;Furthermore such mode based on off-line programing, it is difficult to consider to treat welding line in welding process caused by heat input The opposite deviation for treating welding line relative pose of the welding gun caused by factor such as spatial pose change, wire bending, arc blow, causes to weld Connect quality to be difficult to ensure, particularly some major diameters, the elbow pipe welding of thin-walled.Therefore, the swing arm robot based on off-line programing It is difficult to apply during the actual welding of bend pipe with the welding system that positioner is combined.Therefore, it is medium-and-large-sized curved with reference to ship The demand of the intelligent welding of pipe ring weld seam, researches and develops the automatic welding of a set of flexible, low cost medium-and-large-sized bend pipe girth joint System has important application value.
The content of the invention
To solve the above problem present in the prior art, the utility model provides oneself of large and medium-sized bend pipe girth joint peculiar to vessel Dynamicization welder, realizes positioner and mobile welding robot Collaborative Control, and welding torch position can accurately be directed at bend pipe in real time Welding position, welding efficiency is high, and quality is easily guaranteed that.
The automatic welding device of the utility model large and medium-sized bend pipe girth joint peculiar to vessel, including at motion controller, image Device, weld joint tracking module, slide, multiple positioners and the multiple position sensors being arranged on slide are managed, slide is equipped with can The slide unit moved along slide, is fixed with welding robot on slide unit, welding robot is connected by swinging arc device with welding gun, to be welded curved Pipe clamp is on positioner;Slide unit, slide and multiple position sensors are used for realization welding robot with becoming where bend pipe to be welded The matching that position seat in the plane is put;Weld joint tracking module capture in the welding position of bend pipe to be welded, welding process bend pipe posture to be welded and The variable quantity that weld seam is occurred, and send motion controller to after image processor is handled, controlled and welded by motion controller The hunting frequency of robot motion track and swinging arc device, amplitude.
Preferentially, the bend pipe to be welded being installed on same positioner is same type of.The bend pipe to be welded is S-shaped, U-shaped Or L-shaped.
Preferentially, the weld joint tracking module includes laser range sensor and weld seam visual sensor, weld joint tracking mould Root tuber combines laser according to the laser range sensor that laser range sensor measures and the distance of the welding position of bend pipe to be welded Distance measuring sensor and the relatively-stationary spatial relationship of weld seam visual sensor, converse weld seam visual sensor and bend pipe to be welded The actual object distance of welding position, and contrasted with theoretical object distance, and then realize the object distance adjustment of weld seam visual sensor, Object distance after adjustment is captured as to the welding position of bend pipe to be welded.
Compared with prior art, the utility model has the following advantages that and beneficial effect:
1st, intelligent control is carried out to positioner, completes the Mobile welding machine based on displacement sensor, visual sensor People's self adaptive control, realizes positioner and mobile welding robot Collaborative Control, and welding torch position can accurately be directed at bend pipe in real time Welding position.
2nd, since each positioner can clamp same type of bend pipe (such as S-shaped, U-shaped or L-shaped), multiple positioners can fit A series of bend pipe boxing seam welding of models is answered, thus the utility model can weld the bend pipe ring of polymorphic type, be applicable in model Enclose the work efficiency for extensively, also improving overall operation.
Brief description of the drawings
Fig. 1 is the system block diagram of the utility model;
Fig. 2 is positioner Motor execution module map;
Fig. 3 is welding robot Motor execution module map;
Fig. 4 is the relative position relation figure of workpiece surface to be welded, laser and visual sensor;
Fig. 5 is the bias schematic diagram of assembling seam to be welded.
Embodiment
The utility model is described in further detail with reference to the accompanying drawings and examples, but the implementation of the utility model Mode not limited to this.
Such as Fig. 1, the utility model automatic welding system include motion controller, image processor, weld joint tracking module, Slide, multiple positioners and the multiple position sensors being arranged on slide, slide is equipped with the slide unit that can be moved along slide, sliding Four-degree-of-freedom manipulator (i.e. welding robot) is fixed with platform, four-degree-of-freedom manipulator is connected by swinging arc device with welding gun, weldering Image of the tracking module captured line structured light projection in bend pipe assembling seam region to be welded is stitched, it is opposite to obtain welding gun through image processor The information such as corner bead bias and weld width, and motion controller is transferred to, by motion controller according to welding gun phase Mobile welding robot movement locus is planned in real time to corner bead bias information;According to weld width information, implementary plan The running parameter of swinging arc device, the elbow pipe welding position to be welded for making welding gun be accurately aligned with appropriate technological parameter on positioner.Weldering Seam tracking module includes laser range sensor and weld seam visual sensor.
The utility model places same type of bend pipe (such as S-shaped, U-shaped or L-shaped) on a positioner, i.e., each The bend pipe that positioner is clamped is same type of, and multiple positioners are suitable for a series of bend pipe boxing seam welding of models.Such as Fig. 2, each positioner is equipped with positioner Motor execution module, for clamping workpiece to be welded so that workpiece relative movement to be welded Welding robot is in relatively reasonable spatial pose, obtains preferable welding position and speed of welding.If positioner is locally sat Mark system is o1x1y1z1, positioner Motor execution module include displacement machine base 20, around z1Direction rotating mechanism and driving device 21, Along z1Direction lifting structure and driving device 22, around y1Direction rotating mechanism and driving device 23, around x1Direction rotating mechanism and drive Dynamic device 24, clamping device and driving device 25, around z1Direction rotating mechanism and driving device 21, along z1Direction lifting structure and Driving device 22 is fixed in displacement machine base 20, around y1The both ends of direction rotating mechanism and driving device 23 respectively with around z1Side To rotating mechanism and driving device 21, around x1Direction rotating mechanism and driving device 24 connect, clamping device and driving device 25 It is arranged on around x1The end of direction rotating mechanism and driving device 24.Bend pipe to be welded is installed on clamping device.
The utility model sets welding robot Motor execution module, and foregoing slide unit, slide and multiple position sensors are used In realizing welding robot and the matching of positioner position where bend pipe to be welded, after the completion for the treatment of location matches, welding robot is transported Dynamic execution module drives welding gun to stitch welding along assembling to be welded.Such as Fig. 3, if welding robot local coordinate system is o2x2y2z2, weldering Welding robot Motor execution module is included around x2To rotational motion mechanism and driving device 36, around y2To rotational motion mechanism and drive Move device 35 and around z2To rotational motion mechanism and driving device 34, around y2To rotational motion mechanism and the both ends of driving device 35 Respectively with around x2To rotational motion mechanism and driving device 36, around z2Connected to rotational motion mechanism and driving device 34, around x2To The end of rotational motion mechanism and driving device 36 is installed by swinging arc device and welding gun 39, the laser range sensor of weld joint tracking module 38 and weld seam visual sensor 37.The slide that welding robot is slided with slide unit includes x2Direction guiding rail 31 and y2Direction guiding rail 32 is more A position sensor 33 is arranged on x2On direction guiding rail 31, slide unit is along x2Change when direction guiding rail 31 slides corresponding to welding robot Positioner system, that is, change welding post;Slide unit is along y2Change welding robot when direction guiding rail 32 slides relative to corresponding The distance of positioner, to adjust the welding distance between welding gun and bend pipe to be welded to optimum state.
The utility model sets weld joint tracking module to be used for the position for detecting, tracking actual welds in real time.Assuming that in station i (i.e. positioner i) places, the corresponding theoretical work position of mobile welding robot are i0, then the effect of position sensor is exactly to realize At station i, the rough matching of positioner and mobile welding robot station.The hand that laser range sensor passes through laser ranging Section, realizes the ranging of laser range sensor and workpiece to be welded place's distance to be welded, with reference to laser range sensor and weld seam vision The relatively-stationary spatial relationship of sensor, converses the actual object distance of weld seam visual sensor and workpiece to be welded, and with theoretical thing Away from being contrasted, and then realize the object distance adjustment of visual sensor.
As shown in Figure 4, using the section in face 40 where the welding of bend pipe girth joint to be welded as x0y0Plane, its normal are z0Side To the tangent line of girth joint is x0Direction, the origin of positioner is coordinate origin o0, establish workpiece welding job coordinate system o0x0y0z0.Understood according to laser range sensor and the relative tertiary location relation of weld seam visual sensor, weld seam visual sensing Device is in work coordinate system o0x0y0z0In actual tracking height (vision system object distance hv0) be:
Assuming that the theoretical object distance of vision system is hv, then weld joint tracking highly deviated amount Δ h0For:
Visual sensor is by obtaining image of the line-structured light in workpiece surface to be welded, with reference to vision system calibration parameter ζ (mm/pixel), relative space relation between camera, laser line generator, workpiece to be welded, welding gun, converses bias, the weldering of welding gun The information such as slit width degree, and then the information such as welding gun movement locus, swinging arc device parameter (amplitude of fluctuation, frequency) are planned in real time.
In Fig. 5,51 be actual assembling seam position to be welded, and 52 be theoretical assembling seam position to be welded, and 53 be theoretical construct light Projection, 54 be practical structures ray cast.As shown in Figure 5, if global coordinate system is XYZ, its origin O is mobile welding robot Along x2The theoretical starting point of direction guiding rail movement, positioner is located on x/y plane, and relative position is fixed in global coordinate system.Depending on Feel that (angle between camera optical axis and laser line generator optical axis is α to system neutral structure light using inclination anglez0) project workpiece to be welded Surface.During portable weld joint tracking, if the section of the vertical bend pipe girth joint to be welded of weld joint tracking module is treated along theory When being welded with seam track welding, theoretical weld joint tracking is highly hv(i.e. theoretical Visual Tracking System object distance), laser rays is to be welded The flex point A modulated at assembling seam track0、B0、M0、N0Distribution is located at field of view center, its elements of a fix in image coordinate system Respectively (uA, vA)、(uB, vB)、(uM, vM)、(uN, vN)、(uA0, vA0)、(uB0, vB0)、(uM0, vM0)、(uN0, vN0)。
The visual sensor of the present embodiment welding tracking module uses camera captures images information, is thrown for obtaining structure light Hachure.Since weld joint tracking module is vertical with treating girth welding place section, therefore it may be assumed that the point in t moment, camera coordinates system (ut, vt) in work coordinate system o0x1y1z1Relation be:
Wherein [Δ x, Δ y, Δ z] is the translation matrix of t moment camera coordinates system and global coordinate system, unit mm, ε x, ε y are calibration system, unit mm/pixel.If t+ time Δts, the structured light projection line of acquisition, at this time structure light waiting to be welded It is A, B, M, N with the flex point modulated at seam, its elements of a fix in image coordinate system is respectively (uA, vA)、(uB, vB)、 (uM, vM)、(uN, vN), then the bias that the assembling relatively to be welded of weld joint tracking module is sewn on y directions is:
The course of work of the utility model automatic welding system, comprises the following steps:
1. bend pipe is attached on positioner by worker, and input each bend pipe wall thickness and diameter information to corresponding displacement Machine.
2. starting welding system, motion controller controls slide unit along x2Direction moves to precalculated position, and precalculated position is by position Sensor is put to provide.When the position sensor on portal frame detects slide unit, detection signal is passed into motion controller, is transported Movement controller control slide unit stops.
3. welding position is captured by weld joint tracking module, the position of welding will be needed on bend pipe to be welded after image processor is handled Put and shape information sends motion controller, then movement locus and swinging arc device by motion controller planning welding robot to Running parameter.
4. the source of welding current and wire feeder start, start to weld.
5. since bend pipe posture in welding process and weld seam can change, these changes are caught by weld joint tracking module Obtain.Weld joint tracking module capture welding process centerline construction light is projected in the image in bend pipe assembling seam region to be welded, at image Manage device and obtain welding gun with respect to corner bead bias and weld width information, and be fed back to motion controller, motion control Device plans mobile welding robot movement locus in real time according to welding gun with respect to corner bead bias information;Believed according to weld width Breath, the running parameter of implementary plan swinging arc device, and then the adaptive adjustment for realizing parameter in welding process.
6. continued after the completion of an elbow pipe welding by motion controller control slide unit along x2The direction of motion moves to next Precalculated position, repeat step 3-6, until all welding is completed.
Unloading task is completed by worker after the completion of welding.Whole welding process only has two links to need worker to participate in, and one A is loading and input information process, the other is unloading bend pipe.
As described above, it can preferably realize the utility model.

Claims (8)

1. the automatic welding device of large and medium-sized bend pipe girth joint peculiar to vessel, it is characterised in that including motion controller, image procossing Device, weld joint tracking module, slide, multiple positioners and the multiple position sensors being arranged on slide, slide is equipped with can edge The slide unit of slide movement, is fixed with welding robot on slide unit, welding robot is connected by swinging arc device with welding gun, bend pipe to be welded It is installed on positioner;Slide unit, slide and multiple position sensors are used for realization welding robot with being conjugated where bend pipe to be welded The matching that seat in the plane is put;Weld joint tracking module captures bend pipe posture to be welded and weldering in the welding position of bend pipe to be welded, welding process Seam variable quantity occurred, and send motion controller to after image processor is handled, bonding machine is controlled by motion controller The hunting frequency of device people movement locus and swinging arc device, amplitude.
2. the automatic welding device of large and medium-sized bend pipe girth joint peculiar to vessel according to claim 1, it is characterised in that clamp Bend pipe to be welded on same positioner is same type of.
3. the automatic welding device of large and medium-sized bend pipe girth joint peculiar to vessel according to claim 2, it is characterised in that described Bend pipe to be welded is S-shaped, U-shaped or L-shaped.
4. the automatic welding device of large and medium-sized bend pipe girth joint peculiar to vessel according to claim 1, it is characterised in that described Weld joint tracking module includes laser range sensor and weld seam visual sensor, and weld joint tracking module is according to laser range sensor The laser range sensor measured and the distance of the welding position of bend pipe to be welded, and combine laser range sensor and weld seam vision The relatively-stationary spatial relationship of sensor, converses weld seam visual sensor and the actual object distance of the welding position of bend pipe to be welded, And contrasted with theoretical object distance, and then realize the object distance adjustment of weld seam visual sensor, the object distance after adjustment is captured For the welding position of bend pipe to be welded.
5. the automatic welding device of large and medium-sized bend pipe girth joint peculiar to vessel according to claim 4, it is characterised in that described Weld seam visual sensor uses camera captures images information.
6. the automatic welding device of large and medium-sized bend pipe girth joint peculiar to vessel according to claim 1, it is characterised in that each Positioner is equipped with the positioner Motor execution module for being used for clamping bend pipe to be welded;If positioner local coordinate system is o1x1y1z1, Positioner Motor execution module includes displacement machine base, around z1Direction rotating mechanism and driving device, along z1Direction lifting structure and Driving device, around y1Direction rotating mechanism and driving device, around x1Direction rotating mechanism and driving device, clamping device and driving Device, around z1Direction rotating mechanism and driving device, along z1Direction lifting structure and driving device are fixed in displacement machine base, Around y1The both ends of direction rotating mechanism and driving device respectively with around z1Direction rotating mechanism and driving device, around x1Direction rotates Mechanism and driving device connection, clamping device and driving device are arranged on around x1The end of direction rotating mechanism and driving device.
7. the automatic welding device of large and medium-sized bend pipe girth joint peculiar to vessel according to claim 1, it is characterised in that described Welding robot is equipped with welding robot Motor execution module;If welding robot local coordinate system is o2x2y2z2, bonding machine Device people's Motor execution module is included around x2To rotational motion mechanism and driving device, around y2To rotational motion mechanism and driving device With around z2To rotational motion mechanism and driving device, around y2To the both ends of rotational motion mechanism and driving device respectively with around x2To Rotational motion mechanism and driving device, around z2Connected to rotational motion mechanism and driving device, around x2To rotational motion mechanism and drive The end installation swinging arc device and welding gun of dynamic device.
8. the automatic welding device of large and medium-sized bend pipe girth joint peculiar to vessel according to claim 7, it is characterised in that described Slide includes x2Direction guiding rail and y2Direction guiding rail, multiple position sensors are arranged on x2On direction guiding rail.
CN201721095636.4U 2017-08-30 2017-08-30 The automatic welding device of large and medium-sized bend pipe girth joint peculiar to vessel Expired - Fee Related CN207223255U (en)

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN107414248A (en) * 2017-08-30 2017-12-01 广州航海学院 Towards the automatic welding system and method for the medium-and-large-sized bend pipe girth joint of ship
CN117817213A (en) * 2024-03-05 2024-04-05 泰州润伟机械有限公司 Automatic welding machine for welding seams
CN117817213B (en) * 2024-03-05 2024-05-24 泰州润伟机械有限公司 Automatic welding machine for welding seams

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN107414248A (en) * 2017-08-30 2017-12-01 广州航海学院 Towards the automatic welding system and method for the medium-and-large-sized bend pipe girth joint of ship
CN107414248B (en) * 2017-08-30 2019-11-15 广州航海学院 Automatic welding system and method towards the medium-and-large-sized bend pipe girth joint of ship
CN117817213A (en) * 2024-03-05 2024-04-05 泰州润伟机械有限公司 Automatic welding machine for welding seams
CN117817213B (en) * 2024-03-05 2024-05-24 泰州润伟机械有限公司 Automatic welding machine for welding seams

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