Welding guarantees the assembly method of pipe banjo fixing butt jointing root gap with the location chock
(1) technical field
The present invention relates to welding technique, particularly relate to welding guarantees pipe banjo fixing butt jointing root gap with the location chock assembly method.
(2) background technology
In the lateral expansion or the contraction distortion of welding process center tap root, directly influence the quality of banjo fixing butt jointing root backing weld seam.When especially welding big linear expansion coefficient material (as stainless steel, nickel-base alloy, acid bronze alloy etc.) root of joint backing weld seam, the distortion of the cross-direction shrinkage of the root of joint can reach 2-3mm, can't guarantee one side welding with back formation technology.In order to realize one side welding with back formation, in welding process, must make the root of joint maintain the fit-up gap.How to guarantee root of joint fit-up gap, become the key point that guarantees banjo fixing butt jointing root backing weld seam quality.All be to adopt GTAW one side welding with back formation technology to above-mentioned big linear expansion coefficient pipe fitting butt joint welding at present, the pipe banjo fixing butt jointing that extensively adopts location mainly contains following several:
A, bypass method tack welding go out in advance the weldering meat of certain altitude in the built-up welding of groove both sides, connect joint welding then and become a tack weld across groove (shown in Figure 1) above groove, and this method is mainly used in the pipe banjo fixing butt jointing assembling and positioning of wall thickness 3-15mm.The problem that exists is that rigidity is not enough, can't guarantee the fit-up gap, and easily groove both sides mother metal be caused damage.
B, the root tack welding that directly feels secure directly welds several sections tack welds (Fig. 2, Fig. 3, shown in Figure 4) at the groove root, and this method can be used for wall thickness 3-15mm pipe.The problem that exists is that the root joint is too much, and positioning and rigid is not enough, can't guarantee the fit-up gap, so can't guarantee welding quality.
C, embed the weldering of welding wire integrated positioning, be embedded in a diameter in the gap and require the suitable welding wire in gap to be used for to force to guarantee the gap, combined with bypass method or the root location that directly feels secure, after closing on the backing weld seam welding and finishing, take off this welding wire.Described method makes groove be destroyed easily, and welding wire contacts for point with bevelled edge, the positioning and rigid deficiency, and the fit-up gap is difficult to guarantee that welding point is too much, also can't guarantee root backing weld seam quality.
(3) summary of the invention
The technical problem to be solved in the present invention provides and a kind ofly can improve welding quality, welding simple to operate guarantee pipe banjo fixing butt jointing root gap with the location chock assembly method.
The technical scheme that adopts is:
Welding is managed the assembly method of banjo fixing butt jointing root gap with locating the chock assurance, comprising:
According to the pipe wall thickness, adopt U-shaped groove or V-butt, I shape groove and process above-mentioned groove respectively at two pipe joints by the process stipulation parameter according to process stipulation;
According to the some location chock of the groove type processing of adopting with the groove section same size;
According to the pipe diameter size, chock location, location with varying number, the location chock is along position of halving setting on the groove of pipe circumference, and cylindrical or the spot welding of groove both sides that will locate chock and two pipe joints are fixed, its spot welding fixation weld length 10-15mm, palpus guarantees the root gap of process stipulation;
Begun the weldering backing weld seam in certain sequence, be welded to chock place, location, should locate the spot welding fixation weld and grind off with disc wheel, taken off the location chock, the welding backing weld seam that continues has again been got the location chock successively and has been welded remaining backing weld seam.
Above-mentioned pipe wall thickness δ is greater than 15mm, and the U-shaped groove is adopted in process stipulation, and process stipulation parameter: bevel angle β is that 15 ° ± 2 °, root gap b are that 3 ± 1mm, root root face P are 2+0.2mm; Pipe wall thickness 3≤δ≤15mm, adopt V-butt, process stipulation parameter: groove angle α is that 60 °+5 °, root gap b are that 3 ± 1mm, root root face P are 1 ± 0.5mm; Pipe wall thickness δ<3mm adopts I shape groove, and the process stipulation parameter: root gap b is 3 ± 1mm.
Above-mentioned according to the pipe diameter size, the location chock is provided with to quartering position along the groove two of pipe circumference.
Above-mentioned location chock adopts with pipe to be made with material materials processing.
The good effect that the present invention obtains is:
1, adopt distinctive technological measure and method of operating to solve because the problem that the distortion of backing weld seam cross-direction shrinkage causes the fit-up gap to guarantee.
2, favourable assurance one side welding with back formation technology is carried out smoothly.
3, locating effect is very remarkable, and the fixedly removal of location chock is easy and simple to handle, and welding quality is improved.
(4) description of drawings
Fig. 1 is existing bypass method tack welding schematic diagram.
Fig. 2 is the existing U-shaped groove root tack welding schematic diagram that directly feels secure.
Fig. 3 is the existing V-butt root tack welding schematic diagram that directly feels secure.
Fig. 4 is the existing I shape groove root tack welding schematic diagram that directly feels secure.
Fig. 5 is U-shaped groove of the present invention and the packaged schematic diagram of joining of limit plug.
Fig. 6 is the packaged schematic diagram of joining of V-butt of the present invention and limit plug.
Fig. 7 is I shape groove of the present invention and the packaged schematic diagram of joining of limit plug.
(5) specific embodiment
Welding guarantees the assembly method of pipe banjo fixing butt jointing root gap with the location chock, be at stainless steel tube, corronil pipe butt joint welding, adopt GTAW, single-sided welding and double-sided forming process, therefore the gap that must make the root of joint keep gage of wire d+0.5-1.5mm in welding process is pressed the pipe of different-diameter and is processed different grooves.Typical case's pipe joint bevel and size see Table 1.
The typical pipe joint bevel of table 1 size
Groove type | δ(mm) | ?α(°) | ????β(°) | ???b(mm) | ??P(mm) |
U-shaped | >15 | ??—— | ????15+2 | ????3±1 | ??2+0.2 |
V-arrangement | 3≤δ≤15m | ??60+5 | ????—— | ??1±0.5 |
I shape | <3mm | ??—— | ????—— | ??—— |
Embodiment one
Welding is managed the assembly method of banjo fixing butt jointing root gap with locating the chock assurance, comprising:
According to pipe wall thickness δ=16mm, can adopt U-shaped groove (see figure 5) according to δ>15mm in the table 1, be processed into U-shaped groove 1 respectively at two pipe joints, its U-shaped groove 1 groove face angle β is 16 °, root root face P is 2.2mm;
Tubing is stainless steel, adopts with pipe and is processed into location chock 2 with U-shaped groove 1 cross section same size with the material stainless steel;
Bigger according to pipe diameter, with four location chock 2 location, four location chocks 2 are provided with along quartering position on the U-shaped groove 1 of pipe circumference, and U-shaped groove 1 two sides that will locate chock 2 and two pipe joints with argon tungsten-arc welding spot welding fix, its spot welding fixation weld 3 long 15mm, guarantee that root gap b=3.5mm meets the requirement of technology b=3 ± 1mm;
Adopt GTAW, begun the welding backing weld seam by any earlier in order, be welded to chock 2 places, location, should locate the aluminium base iron-free emery wheel of spot welding fixation weld 3 usefulness thin slices grinds off, take off fixedly chock 2, the weldering backing weld seam that continues has again been got location chock 2 successively and has been welded all remaining backing weld seams.
Embodiment two
Welding is managed the assembly method of banjo fixing butt jointing root gap with locating the chock assurance, comprising:
According to pipe wall thickness δ=10mm, can adopt the V-butt (see figure 6) according to 3≤δ in the table 1≤15m, be processed into V-butt 4 respectively at two pipe joints, 60 ° of the angles of its V-butt 4, root root face P is 1mm;
Tubing is stainless steel, adopts with the material stainless steel and is processed into location chock 5 with V-butt 4 cross section same sizes;
Less according to pipe diameter, with three location chock 5 location, three location chocks 5 are along trisection posistion setting on the V-butt 4 of pipe circle, and the cylindrical that will locate chock 5 and two pipe joints is fixed with argon tungsten-arc welding spot welding, its spot welding fixation weld 6 long 15mm, guarantee root gap b=3mm, meet the requirement of technology b=3 ± 1mm;
Adopt GTAW, begun the weldering backing weld seam by any earlier in order, be welded to chock 5 places, location, should locate the aluminium base iron-free emery wheel of spot welding fixation weld 6 usefulness thin slices grinds off, take off location chock 5, the weldering backing weld seam that continues has again been got location chock 5 successively and has been welded all remaining backing weld seams.
Embodiment three
Welding is managed the assembly method of banjo fixing butt jointing root gap with locating the chock assurance, comprising:
According to pipe wall thickness δ=2.5mm, can adopt I shape groove (see figure 7) according to δ<3mm in the table 1, be processed into I shape groove 7 respectively at two pipe joints;
Tubing is corronil, adopts with the material corronil and is processed into location chock 8 with I shape groove 7 cross section same sizes;
Little according to pipe diameter, with two location chock 8 location, two location chocks 8 are provided with along bisection position on the I shape groove 7 of pipe circumference, and the cylindrical that will locate chock 8 and two pipe joints is fixed with argon tungsten-arc welding spot welding, its spot welding fixation weld 9 long 10mm guarantee that root gap b=2mm meets the requirement of technology b=3 ± 1mm;
Adopt GTAW, begin the weldering backing weld seam, be welded to chock 8 places, location by any earlier in order, should locate the aluminium base iron-free emery wheel of spot welding fixation weld 9 usefulness thin slices and grind off, taken off location chock 8, the weldering backing weld seam that continues has again been got remaining location chock 8 and has been welded all backing weld seams.