Shield electric machine stator can and lower flange welding method and the equipment used thereofTechnical field: the present invention relates to a kind of equipment shielding shield electric machine stator can and lower flange welding method and use.
Background technology: shield electric machine is the key equipment in nuclear island of nuclear power station, its integrality is to the safe operation important of primary Ioops, and be directly connected to the success or failure of the non-active nuclear power station technology transfer of third generation AP1000, wherein stator can is the critical process that shield electric machine main pump manufactures in link to lower flange welding; Arranging stator can object is by primary Ioops coolant media and stator winding is completely isolated comes, and the girth joint of stator can to lower flange ensures sealing, prevents the key that cooling agent is revealed.And traditional GTAW method heat input is wayward, easily cause mother metal over hot melting to be even out of shape, and weldquality is affected by human factors seriously, quality is unstable, repair rate is high, therefore uses traditional handicraft cannot meet the designing requirement of this product housing.For ensureing motor performance, improving housing product quality, needing to adopt new welding procedure.
Summary of the invention: the object of this invention is to provide a kind of shield electric machine stator can to lower flange welding technique, realize uniform ring seam welding, deflection is excessive, the discontinuous defect such as to exceed standard of pore, crackle, incomplete fusion and surface to avoid postwelding to occur.
Technical scheme of the present invention is: a kind of shield electric machine stator can and lower flange welding method:
(1) motor-driven silk filling tungsten argon arc soldering method is adopted to weld shield electric machine stator can and lower flange joint, argon tungsten-arc welding is using argon gas as protective gas, utilize the welding process of arc heat fusing mother metal and the filler wire produced between tungsten electrode and base metals, the filling of welding wire is sent to certain speed by the side of mechanical transmission mode in welding direction;
(2) according to joint specific constructive form and size, design and manufacture the special welding head (1) can walked on fixing ring-shaped guide rail, head (1) be integrated with mechanical wire feeder (2) and possess welding arc control function tungsten argon arc welding gun (3); Design and manufacture the frock coordinating this head to use
(3) according to joint concrete structure size, adjustment welding parameter, selects the electric current of coupling, voltage, wire feed rate and speed of welding, and adjustment head and wire-feeding pipe send angle to reach best continuous fill conditions, obtain optimal weldquality;
(4) the shield electric machine stator can of thin wall cylinder-shaped structure adopts American Society Testing and Materials (ASTM) standard B575 material, length 3676mm, external diameter 591.236mm, wall thickness 0.381mm, lower flange adopts American Society of Mechanical Engineers (AMSE) (ASME) standard SA336GradeF304 material, internal diameter is coordinated to be 591.82mm with housing, select and the Ni-Cr-Mo of matrix constituent similar nature (American Welding Society (AWS) (AWS) standard A 5.14/A5.14M ERNiCrMo-4) welding wire, in conjunction with the welding machine wire feed requirement of special-purpose machinery, select the packing material of disc-like form, gage of wire is 0.020 " (0.5mm), be loaded on supporting wire feeding disc, power is provided by the wire feeder on special-purpose machinery during welding point, realize continuous wire feed,
(5) welding method: a) clear up housing and lower flange surface, keep lower flange end face at horizontal level, housing is also fixing through lower flange, and holding workpiece is in downhand position; B) purification air bag is installed in stator can inner chamber, continues to provide sufficient auxiliary protection argon gas, guarantee in housing, to form protective gas cavity in whole welding process.The supporting tool and cooling copper ring cleared up are installed, ensure that lower flange 8 end face is concordant with housing 9 top edge, air ring 10 position is apart from housing top edge about 0.035 " after (0.889mm); regulate stretching air ring; ensure that air ring and housing paste tight as far as possible, eliminate the gap of cooling copper ring and housing; C) by argon tungsten-arc welding head together with guide rails assembling to supporting tool, guarantee that tungsten electrode, welding wire meet the requirements relative to the angle of housing, position, the specification such as the electric current of adjustment coupling, voltage, wire feed rate and speed of welding before welding; D) motor-driven tungsten argon arc soldering method is adopted to weld, workpiece is fixed, welder head moves along guide rail uniform circular motion, welder is Real-Time Monitoring welding pool in welding process, and welding parameters and wire feed position are finely tuned, keep wire feed position to be positioned at welding pool center, ensure that in welding process, molten bath is stablized, welding line joint cool to room temperature in atmosphere after welding; E) postwelding butt welded seam quality checks, utilizes five times of magnifying glass butt welded seam joint outer surfaces to carry out checking and liquid penetrant inspection, and appearance of weld is good, and Non-Destructive Testing is qualified, reaches Expected Results.
Another object of the present invention is to provide one and guarantees that welding gun is parallel to housing axially all the time, and the shield electric machine stator can realizing the welding of cylinder end circular weld welds equipment used with lower flange.This equipment and technology scheme is: a kind of shield electric machine stator can welds equipment used with lower flange, it is characterized in that: welding head (1) is gone up integrated mechanical wire feeder (2) and possessed welding arc control function tungsten argon arc welding gun (3); The frock coordinating head (1) to use comprises: ring-shaped guide rail (5), copper air ring (10), support (4), air bag (7) and bracket (6); Head (1) integrated wire feeder (2) and tungsten electrode argon arc welding gun (3), support (4) top and welding machine guide rail (5) is installed, support (4) bottom and air ring (10) is installed, bracket (6) is placed on for fixed support (4) on lower flange (8), and air bag (7) is installed on stator can inner chamber (9); To ensure that lower flange (8) end face is concordant with housing (9) top edge before welding, air ring (10) axial direction is a little less than weld seam.
The present invention is optimized conventional method with motor-driven silk filling tungsten argon arc soldering method: first, weld seam automatic filling is realized by mechanical wire feeder, and by the welding arc control function of welding gun, can according to the shaping situation of actual welds, speed of welding and feed rate of welding wire are adjusted accordingly, final acquisition is shaped evenly attractive in appearance, the weld seam of reliable in quality, avoiding manual silk filling of traditional-handwork argon tungsten-arc welding causes efficiency low, and due to problems such as the uneven weld defects caused of the hand torch uneven welding joint shaping caused of heating; Secondly, be different from the welding gun vertical axial rotating welding mode of pipeline welding equipment, use special welding head provided by the present invention, when it is walked along guide rail, can guarantee that welding gun is parallel to housing axially all the time, realize the welding of cylinder end circular weld; Finally, use air ring frock stretching housing and lower flange, ensure that its play movement is even, because copper material is than housing material softness, damage can not be caused to it, the heat conductivility that copper is excellent simultaneously, effectively can cool weld seam, when avoiding welding, excessive heat input causes housing material to melt distortion, significantly improves appearance of weld, ensures weldquality; This process obtains checking on welding analog part, and weldquality is good, reaches expection requirement.
Accompanying drawing illustrates:
Fig. 1 is that shield electric machine stator can welds schematic diagram with lower flange
Fig. 2 is that shield electric machine stator can welds air ring and assembles schematic diagram with lower flange
Detailed description of the invention:
A kind of shield electric machine stator can and lower flange welding method:
(1) motor-driven silk filling tungsten argon arc soldering method is adopted to weld shield electric machine stator can and lower flange joint, argon tungsten-arc welding is using argon gas as protective gas, utilize the welding process of arc heat fusing mother metal and the filler wire produced between tungsten electrode and base metals, the filling of welding wire is sent to certain speed by the side of mechanical transmission mode in welding direction;
(2) according to joint specific constructive form and size, design and manufacture the special welding head 1 can walked on fixing ring-shaped guide rail, head 1 be integrated with mechanical wire feeder 2 and possess welding arc control function tungsten argon arc welding gun 3; Design and manufacture the frock coordinating this head to use;
(3) according to joint concrete structure size, adjustment welding parameter, selects the electric current of coupling, voltage, wire feed rate and speed of welding, and adjustment head and wire-feeding pipe send angle to reach best continuous fill conditions, obtain optimal weldquality;
(4) the shield electric machine stator can of thin wall cylinder-shaped structure adopts American Society Testing and Materials (ASTM) standard B575 material, length 3676mm, external diameter 591.236mm, wall thickness 0.381mm, lower flange adopts American Society of Mechanical Engineers (AMSE) (ASME) standard SA336GradeF304 material, internal diameter is coordinated to be 591.82mm with housing, select and the Ni-Cr-Mo of matrix constituent similar nature (American Welding Society (AWS) (AWS) standard A 5.14/A5.14M ERNiCrMo-4) welding wire, in conjunction with the welding machine wire feed requirement of special-purpose machinery, select the packing material of disc-like form, gage of wire is 0.020 " (0.5mm), be loaded on supporting wire feeding disc, power is provided by the wire feeder on special-purpose machinery during welding point, realize continuous wire feed,
(5) welding method: a) clear up housing and lower flange surface, keep lower flange end face at horizontal level, housing is also fixing through lower flange, and holding workpiece is in downhand position; B) purification air bag is installed in stator can inner chamber, continues to provide sufficient auxiliary protection argon gas, guarantee in housing, to form protective gas cavity in whole welding process.The supporting tool and cooling copper ring cleared up are installed, ensure that lower flange 8 end face is concordant with housing 9 top edge, air ring 10 position is apart from housing top edge about 0.035 " after (0.889mm); regulate stretching air ring; ensure that air ring and housing paste tight as far as possible, eliminate the gap of cooling copper ring and housing; C) by argon tungsten-arc welding head together with guide rails assembling to supporting tool, guarantee that tungsten electrode, welding wire meet the requirements relative to the angle of housing, position, the specification such as the electric current of adjustment coupling, voltage, wire feed rate and speed of welding before welding; D) motor-driven tungsten argon arc soldering method is adopted to weld, workpiece is fixed, welder head moves along guide rail uniform circular motion, welder is Real-Time Monitoring welding pool in welding process, and welding parameters and wire feed position are finely tuned, keep wire feed position to be positioned at welding pool center, ensure that in welding process, molten bath is stablized, welding line joint cool to room temperature in atmosphere after welding; E) postwelding butt welded seam quality checks, utilizes five times of magnifying glass butt welded seam joint outer surfaces to carry out checking and liquid penetrant inspection, and appearance of weld is good, and Non-Destructive Testing is qualified, reaches Expected Results.
As shown in Figure 1, a kind of shield electric machine stator can welds equipment used with lower flange, integrated mechanical wire feeder 2 and possess welding arc control function tungsten argon arc welding gun 3 on welding head 1; The frock coordinating head 1 to use comprises: ring-shaped guide rail 5, copper air ring 10, support 4, air bag 7 and bracket 6; The integrated wire feeder 2 of head 1 and tungsten electrode argon arc welding gun 3, support 4 tops and install welding machine guide rail 5, and support 4 bottoms and install air ring 10, bracket 6 is placed on for fixed support 4 on lower flange 8, and air bag 7 is installed on stator can inner chamber 9; As shown in Figure 2, will ensure that lower flange 8 end face is concordant with housing 9 top edge before welding, air ring 10 axial direction is a little less than weld seam.