2006, liaoyang rock oil steel pipe plant undertook the assembly of some steel pipes of a definite pipeline, with the diameter of steel pipes being 219mm seventeen.2mm, steel grade X70, adopt spiral seam double facet submerged arc attachment.The production schedule is tight, the task is significant, the technical commonplace is high, the technical specification is extremely strict, the attachment quality necessities are terribly high.In order to finish the assembly task with prime quality and high potency, it's necessary to regulate the attachment current and Angle of welding wire of the welding unit, and improve the instrumentation like automatic seam following system, thus on improve the attachment quality and meet the necessities of the owner.
1-Add attachment current show device for external welding device
1 Lincoln Na one-5 management box is adopted for the control of dc attachment outside the welding unit. Its attachment management characteristic is CV (constant voltage control), and also the attachment parameters together with welding voltage, wire feeding speed and attachment speed may be predetermined.The panel of the management box has the show of attachment voltage and wire feeding speed, however no show of attachment current, as shown in figure one.Since there's no correct show of attachment current, once the supervisor and also the owner got to apprehend the attachment current of the looks diagram of the na-5 management enclose figure one, they'll solely use the digital pincer meter to live it for five to six times, and take the norm. The measure method takes a protracted time and incorporates a giant error.Therefore, it absolutely was set to put in associate meter to show the attachment current.
1.2 implementation methodology has 3 strategies to choose: (1) exploitation pointer ammeter;(2) using digital ammeter;(3) using the first current sensing element style display device.The pointer kind meter has the characteristics of economic and sensible, simple to put in, simple to take care of and small stricken by the surroundings, etc. Combining with the particular scenario of the workshop and touching on Na - 3S and Na - four management box, it's set to adopt the pointer kind meter and shunt to make the external attachment dc show device.Ammeter adopts magnetoelectric kind, model 63C18, vary one five hundred A.The specific methodology is as follows: when the meter and shunt are connected in parallel, they're connected asynchronous to the attachment handle wire, as shown in figure a pair of.After putting in the device, the operator will alter the attachment current accurately and intuitively, thus on effectively monitor the attachment current.
2.Automatic seam following system
2.1 improvement planThe original automatic attachment seam following device has low accuracy, poor period performance, long interval, and wishes the cooperation of operators, that cannot meet the necessities of attachment method during this production.Therefore, it absolutely was set to put in aspect weld weld automatic following system severally for internal and external attachment.
2.2 system compositionVista Weld Weld automatic following system consists of sensing element elements, servo motor actuators, industrial pc image process elements, controller elements, etc.The system takes optical device stripe because the operating medium, and once the optical device stripe image is nonheritable by the camera, it's sent to the pc for image process, and also the mechanism completes the action when getting the result.The device has the benefits of high responsibility, stable operation, easy structure and convenient installation and maintenance.The system structure diagram is shown in figure three.
2.3 ruleThe operating principle of the optical device structured lightweight methodology for visual sensing is shown in figure four. just one optical device stripe is drawn here, and also the alternative 2 are a similar.This system belongs to the attachment seam following system that adopts optical device because the active source of illumination.The source of illumination from the optical device tube is reworked into a strip light source by the columnar mirror and projected onto the weld groove of the piece of work.CCD camera receives the bevel-shaped optical device stripe mirrored by the diffuse reflection from the piece of work. Through the image acquisition and image process, it may be acknowledged that the middle position of the deformation of the optical device stripe is that the center line of the weld.The optical device stripe image collected by CCD camera is shipped to the pc for image process, and is compared with the set central position. once there's a deviation between the 2, the system problems a correction command, and also the PLC and managementler control the servo motor action to finish the correction and following method.This methodology cannot solely find the central position of the weld, however conjointly acquire the characteristic parameters of the form and size of the weld section, that is appropriate numerous} welds and various attachment strategies.It is verified that the automated following system will correct the little deviation within the method of attachment, greatly scale back the attachment deviation, non-fusion and alternative attachment defects, and improve the standard of attachment.Compared with ancient following instrumentation and manual operation, this technique has the benefits of high following preciseness, quick response, easy and convenient operation, friendly human-machine interface, etc., and absolutely meets the necessities of steel pipe forming and attachment.The field application photos of the optical device following system are shown in figure five.Figure five field application of optical device following system
2.4 existing problemsIf the operating surroundings is dirty , particularly if the dirt contains an oversized quantity of magnetic attraction particles, it'll result in the failure of the bit screen show and also the touch perform failure.If the show installation position is on the point of the tube body, it'll be subject to magnetic force interference, simple to look graphic distortion, in order that the clarity of the show faded.Sometimes, thanks to plate rolling, the front and rear heel following result isn't good: at now, the manual management box ought to be place into the "manual adjustment" state to regulate the following system manually.
3.Improve output capability of internal attachment device journeyman
3.1 improvement planThe pipe incorporates a diameter of l 219 millimetre one7.2 mm, fabricated from X70 category pipeline steel, the attachment current of internal welding dc throughout traditional production will reach 1350 ~ l400A, on the point of the utmost output current of the attachment machine.At the initial stage of production, one set of attachment machine is employed for internal welding dc. once an oversized attachment current has to be output, the adjustment knob has been adjusted to the limit. Meanwhile, the temperature rise and failure rate of the attachment machine are considerably exaggerated, leading to the decline of internal attachment quality.Therefore, the interior attachment current was modified to be output in parallel by a pair of welding machines to extend the output current and improve the welding quality.
3.2 implementation methodConnect 2 Lincoln welders (DC - 1500) in parallel to make one main and one auxiliary.Internal control is connected per relevant principles of Lincoln journeyman.Lines four and thirty one of the most machine are connected with lines 4 and 31 comparable to the auxiliary machine. Lines 75, seventy six and seventy seven of the most machine are connected with Na 1 3s of the management box of Lincoln journeyman, and outwardly connected into parallel output, as shown in figure half-dozen.Field application shows that when exploitation a pair of attachment machines in parallel, the present output capability of internal attachment DC is considerably improved, the vary of current adjustment is enlarged, and attachment defects like scum inclusion and incomplete welding are considerably reduced, so greatly rising the attachment quality.After being place into operation, the journeyman works swimmingly and dependably with traditional temperature rise and no failure.
4.Improve internal wire feeding mechanism
The original internal wire feeding mechanism is fastened with a pair of wire feeding rods on the support frame. there's no Angle standardisation on that. once the operator adjusts the Angle of the wire on every occasion, it takes a protracted time and it's tough to manage the Angle adjustment.Sometimes the wire rod can swing with the bridge thanks to the unstable fixation, leading to the deviation of attachment purpose. Therefore, a brand new wire feeding mechanism is meant.The new wire feeding mechanism consists of a fan-shaped plate, a screw rod and a connecting Angle steel. There are four arc grooves on the fan-shaped plate. The connecting Angle steel is connected to the arc groove on one facet and also the screw rod on the opposite side, as shown in FIG. 7.After the wire feeding mechanism is improved, the wire feeding rod is fastened firmly and dependably, in order that the attachment purpose is not any longer offset.When exchange the wire feeding nozzle, if the wire Angle is offset, the quality Angle example may be used for comparison measure, thus on alter the wire Angle, wire spacing, before and when and left and right deviation and alternative parameters a lot of quickly and accurately.It is simple to work and greatly improves the attachment stability.The specification of pipeline steel pipe throughout traditional continuous production, wire feeding mechanism parameter is ready to: one silk from the higher edge is twenty five millimetre, one 旽 wire from the lower fringe of thirty eight mm;The higher a part of no. a pair of wire is twenty eight millimetre removed from the plate edge, and also the lower a part of no. a pair of wire is sixteen millimetre removed from the plate edge.The Angle between the 2 wires is twenty seven degrees.
After the implementation of the higher than improvement schemes, it's been verified by field use that not solely the attachment quality has been improved, however conjointly smart results are achieved in reducing the intensity of labor of staff, increasing the use rate of apparatus and reducing operational errors, etc., meeting the necessities of supervisors and house owners and with success finishing the assembly task of the pipeline.
Business scope: 21.3mm-3620mmLSAW submerged arc welded pipe 325-2020mmERW straight welded pipe 6mm-711mmSMLS seamless tube 10-1120mmSSAW spiral steel tube 219-3620mmDemand for quality suppliers and partners