CN109454313A - A kind of big specification low-alloy steel tube sheet welding plate preparation process - Google Patents
A kind of big specification low-alloy steel tube sheet welding plate preparation process Download PDFInfo
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- CN109454313A CN109454313A CN201810265473.2A CN201810265473A CN109454313A CN 109454313 A CN109454313 A CN 109454313A CN 201810265473 A CN201810265473 A CN 201810265473A CN 109454313 A CN109454313 A CN 109454313A
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K9/00—Arc welding or cutting
- B23K9/16—Arc welding or cutting making use of shielding gas
- B23K9/167—Arc welding or cutting making use of shielding gas and of a non-consumable electrode
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K31/00—Processes relevant to this subclass, specially adapted for particular articles or purposes, but not covered by only one of the preceding main groups
- B23K31/003—Processes relevant to this subclass, specially adapted for particular articles or purposes, but not covered by only one of the preceding main groups relating to controlling of welding distortion
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K31/00—Processes relevant to this subclass, specially adapted for particular articles or purposes, but not covered by only one of the preceding main groups
- B23K31/02—Processes relevant to this subclass, specially adapted for particular articles or purposes, but not covered by only one of the preceding main groups relating to soldering or welding
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K9/00—Arc welding or cutting
- B23K9/235—Preliminary treatment
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Abstract
The invention discloses a kind of big specification low-alloy steel tube sheet welding plate preparation processes, it is characterised in that include the following steps: S1, big specification low-alloy steel welding tube sheet match welding material selection；S2, heavy gauge tube plate are welded with plate welding；S3, big specification plate welding groove type；S4, the group pair of big specification jigsaw and station plate are reinforced；S5, welding sequence and anti-deformation；It is hot after S6, welding plate welding connector；S7, big specification plate welding weld seam non-destructive testing；S8, big specification low-alloy steel jigsaw post weld heat treatment and anti-deformation control.Simple economy practical system of the present invention suitable for big specification low-alloy steel for tube sheet welding plate is standby, and the advantage is that can effectively reduce Raising directly, reduces tooling processing cost, welding material expenditure is few, and technical process is simple and easy, strong operability；Acquisition weldquality is excellent, and surface smoothness meets the welding plate of tube sheet processing request.
Description
Technical field
The invention belongs to heavy gauge tube plate welding technology fields, more specifically more particularly to a kind of big specification low-alloy
Steel pipe plate welding plate preparation process.
Background technique
Large heat exchanger becomes one of the important equipment of big development of chemical industry.Tube sheet as large heat exchanger main component it
One, tube sheet diameter 7000mm or more, thickness 100mm or more.Since diameter is big, thickness is thick, can not use solid forging or monolith
Sheet fabrication manufacture needs to prepare heavy gauge tube plate plate using butt welding method.Pipe sheet for heat-exchange facility is meeting performance requirement
While, tube sheet surface answer it is smooth, flatness be ± 2mm；Secondly, tube sheet welding should use complete penetraction and fusion in welding connector, postwelding carries out nothing
Damage detection, II grades qualified, and low-alloy steel Q345R good combination property, processing technology is mature, and specification is complete, and quality is stablized, and is large-scale heat
The tube sheet of exchanger or the substrate of composite plate tube sheet often use strength materials.
It, can be using increase welding in order to guarantee that heavy gauge tube plate plate reaches the surface smoothness of requirement after welding
Deformed machining allowance is reserved with plate sotck thinkness method, after the completion of welding, removal is processed using machine-tooled method and is become
The excess thickness of shape part, guarantees the design thickness of tube sheet, but due to such tube sheet welding sotck thinkness increase, retaining wall on slope,
Base material loss, welding material expenditure etc. dramatically increase, and dramatically increase manufacturing cost；Second of common method is will to be used for pipe
The tube sheet blank of plate welding reserves a little finish allowance for sealing surface processing, by controlling welding deformation side in welding process
Formula reaches tube sheet processing request to guarantee the planar surface flatness of welding tube sheet, after the completion of the processing of welding tube sheet sweating heat,
Only a small amount of surface is needed to process tube plate sealing face, the size of tubesheet calculation, the blank of such tube sheet welding, processing can be reached
Consumption and welding material expenditure substantially reduce, but the control of welding process anti-deformation requires to significantly improve, and manufacturing cost also significantly subtracts
It is few, it selects the mode of process control welding deformation to advantageously reduce manufacturing cost, improves benefit.
The heavy wall Q345R material of large-scale welding tube sheet, thickness is big, and economic welding method can not once be completed to weld, and needs
Multi-layer multi-pass welding is used, due to the thermal processes act in the road Hou Daoduiqian in welding process, undergo the welding bead first welded will more
Secondary welding thermal process heat treatment and entirety long-time post weld heat treatment, repeatedly heat treatment generates certain influence to strength character,
Strength reduction can be generated；Secondly thick plates are local heating and cooling procedure, and Seam and heat effected zone cooling velocity is fast, are held
It is also easy to produce brittle tissue and hydrogen fuses into, lead to the generation of cold crack.Welding process is expanded with heat and contract with cold due to part, is be easy to cause
Tube plate deformation and weld stress cause size after plate angular deformation and drilling processing unstable, increase orthopedic process and cost or
Tube sheet removal weld seam is caused to weld again.
The performance of main pressurized element of the large-scale tube sheet as heat exchanger, welding welding point should be suitable with base material, weldering
Connecing quality should meet the requirements, and should select reasonable preparation process in conjunction with material therefor Q345R performance characteristics and welding condition, real
The preparation of existing heavy gauge tube plate welding plate.
Summary of the invention
The purpose of the present invention is to solve disadvantages existing in the prior art, and a kind of big specification low-alloy steel proposed
Tube sheet welding plate preparation process.
To achieve the above object, the invention provides the following technical scheme:
A kind of big specification low-alloy steel tube sheet welding plate preparation process, includes the following steps:
S1, big specification low-alloy steel welding tube sheet match welding material selection
According to the base material performance requirement of heavy gauge tube plate, selecting thickness is more than the plate of 80mm and base material with the trade mark, is selected
Alloying element manganese is welded with F48P2-H10Mn2 solder flux as low-alloy steel Q345R slab welding in 1.5~1.9% high manganese welding wire
Connect material；
S2, heavy gauge tube plate are welded with plate welding
By argon tungsten-arc welding bottoming, welding electrode arc welding root thickens welding, recycles efficient single-filament narrow-gap submerged-arc welding
It fills cover welding and completes weld seam, realize the high-quality welding of efficient, low consumption, small deformation；
S3, big specification plate welding groove type
Using double U-groove, it is easily guaranteed that root through welding and is conducive to through the big of Control Welding Process welding deformation
Specification plate welding groove；
S4, the group pair of big specification jigsaw and station plate are reinforced
Two block parts wait organize pair are placed on platform, are grouped, groove size are adjusted, in group to workpiece grooves two
End difference spot welding groove run-on tab consistent with workpiece grooves to be welded and arc-extinguishing plate, prevent the narrow-clearance submerged arc welding starting the arc and receive arc defect
Bring production joint into, increasing vertical and base material at the back side for first welding groove of double grooves to be welded will position with the lateral gusset of intensity
Group is to weld size and improves the rigidity of welding plate, increases non-deformability in welding process, guarantees weldquality and turn
The generation of tearing is prevented in the process；
S5, welding sequence and anti-deformation
After the completion of bottom welding is with welding is thickened, narrow-clearance submerged arc welding is filled the welding sequence of cover welding process
It is the key measure for completing welding control, cooperates groove size variation and tube sheet surface evenness measuring in welding process, it will
Realize effective control of big specification low-alloy steel welding plate welding deformation, basic welding sequence is: preheating-bottom argon arc welding
Welding-welding electrode arc welding thickens groove width depth dimensions measurement-single-filament narrow-gap before welding-narrow-clearance submerged arc welding welds and buries
Alternately pressure road welding-welding process groove depth width measurement-welding plate turn-narrow-clearance submerged arc welding seals arc-welding bilateral
Back welding connect-measures groove depth width-and determines weld metal thickness-back side filling welding-measurement groove width and depth
Degree --- welding plate turn over, and so on when deposited metals thickness reaches 50-55mm, using the aluminum profile ruler of length 5m
The surface evenness measuring for carrying out welding plate, when surface planarity is equal to 4-5mm, welding plate, which starts to turn over, carries out the back side
Weld seam filling welding, the above welding process are continuously finished, until welding terminates；
It is hot after S6, welding plate welding connector
After the completion of needing to stop welding or the welding of whole weld seam in welding process, using axis of a weld as axis, using electricity
It heats crawler belt and is laid with the electric crawler belt close-packed arrays of 300mm wide along fusion length direction, heat-preservation cotton is by the every side 500mm range of weld seam
Local cladding is carried out, carries out weld seam temperature detection using four thermocouples, weld dimensions are heated to 300 DEG C of heat preservations two
Room temperature is down to after hour；
S7, big specification plate welding weld seam non-destructive testing
Detected using lossless detection methods such as diffraction time difference method supersonic detection methods, and as requested carry out detection and
It checks and accepts；
S8, big specification low-alloy steel jigsaw post weld heat treatment and anti-deformation control,
Big specification welding tube sheet enters furnace treatment reason mode using entirety with plate and carries out post weld heat treatment to welding connector, uses
Before the welding plate heat treatment of tube sheet, heat treatment tooling platform is prepared using I-steel, the channel steel height being used to support is not low
In 300mm, channel steel length should than at pad plate grow at least 50mm, each channel steel spacing is not more than 1000mm, and channel steel is placed
Each channel steel is adjusted to same plane afterwards, the good big specification low-alloy steel plate of welding is placed on tooling on the channel steel of leveling
On platform, the heat treatment of postwelding stress-removal is carried out by heat treatment process, completes the preparation of heavy gauge tube plate welding plate.
Preferably, in S2, selection is easy to guarantee weldquality, guarantees through welding and prevents burn-through, can reduce loss, improves
The welding technique of efficiency uses bottom argon arc welding, welding electrode arc welding thickens, narrow-clearance submerged arc welding filling, back cover, capping
Welding procedure mode, ensuring to penetrate and high-quality welding ensure that efficient welding, reducing base material and wlding disappears
Consumption, takes full advantage of the thermal processes act between each passage of narrow gap welding, improves joint performance.
Preferably, in S3, big specification low-alloy steel tube sheet plate welding, it is ensured that weldquality and plate welding table
Face unevenness needs to design the small root face to match with welding technique, low-angle, groove according to selected welding technique
Double U-groove structure similar in depth, it is high-quality and efficient to meet, and can be effectively controlled the purpose of welding deformation.
Preferably, in S4, big specification low-alloy steel tube sheet plate welding, need by technique requirement group to meet welding
It is required that groove, prevent misalignment and gap excessive, bring hidden danger of quality to normal welding process；In rising for weld to be welded
Begin and end up that the receipts arc arc-extinguishing plate of certain length is respectively set, stay in the issuable defect of receipts expulsion of arc arc of submerged-arc welding will not
In production joint；Underside groove in the groove side of welding first increases lateral gusset, it is ensured that groove group is steady to size when welding
It is fixed, increase weldment rigidity, deep groove surveys groove contraction speed when slowing down welding, and it is thick to increase initial stage welding groove side filling metal
Degree guarantees that weld seam has the intensity that tearing is prevented when turning over.
Preferably, in S5, big specification low-alloy steel jigsaw is thickened in preheating, bottom argon arc welding and stick electrode arc welding
Afterwards, it in using narrow-clearance submerged arc welding welding process, needs to turn over welding, then again by specifying measurement groove width and depth
Groove width and depth are measured, welding is turned over, it is so two-sided alternately to weld, weldering is controlled using the deformation rule in welding process
Deformation is connect, surface planarity measurement is carried out when weld metal reaches certain thickness, then using ruler, turns over welding, measure surface
Flatness, such two-sided alternately welding, completes tube sheet jigsaw welding, and the satisfactory tube sheet of formation surface smoothness is used flat
Plate.
Preferably, in S6, after the completion of the plate welding of big specification low-alloy steel tube sheet, the big cooling velocity of tube plate thickness
Fastly, and it cannot be heat-treated improvement tissue and stress state immediately, has so needed to carry out heat after postwelding, rear thermal recovery local heating
Mode carries out, by crawler belt heater by regulation weld seam two sides carry out be laid with and and with heat-preservation cotton it is coated, be heated to 300 DEG C keep the temperature
2 hours, enables the hydrogen sufficiently diffusion evolution in weld seam, prevent cold crack.
Preferably, in S7, whether confirmation heavy gauge tube plate plate welding weld seam meets requirement, using no spoke
It penetrates, to heavy wall workpiece, defect detection sensitivity height, auxiliary material is simple, and energy scene carries out detection and has no effect on life around detection
The diffraction time difference method ultrasound detection internal soundness detection that production personnel work normally, ultrasound detection carry out defect location, and magnetic powder carries out
Surface defects detection, it is ensured that quality of weld joint meets the requirements.
Preferably, in S8, big specification low-alloy steel welding plate postwelding carries out stress-removal heat treatment, eliminates welding point
The brittlement phase that rapid cooling generates is welded, welding point peak stress is reduced, guarantees tubesheet dimension stability, big specification butt welding tube board foot
Very little big, low alloy steel plate intensity and toughness is remarkably decreased under heat treatment temperature, and placement is improper to will cause plate deformation, is needed using heat
Anti-deformation measure is handled, keeps welding planar surface smooth, realizes table after the big specification low alloy steel plate heat treatment that welding is completed
Facial plane degree meets the needs of tube sheet processing in the requirement of ± 5mm range.
A kind of technical effect and advantage of the invention: big specification low-alloy steel tube sheet welding plate system provided by the invention
Standby technique, can effectively reduce Raising directly, reduce tooling processing cost, and welding material expenditure is few, and technical process is simple and easy, behaviour
The property made is strong；Acquisition weldquality is excellent, and surface smoothness meets the welding plate of tube sheet processing request.
Detailed description of the invention
Fig. 1 is the big specification plate welding divided edge structure schematic diagram of the present invention；
Fig. 2 is post weld heat treatment curve graph of the present invention.
Specific embodiment
In order to make the objectives, technical solutions, and advantages of the present invention clearer, below in conjunction with specific embodiment, to this
Invention is further elaborated.It should be appreciated that the specific embodiments described herein are merely illustrative of the present invention, not
For limiting the present invention.Based on the embodiments of the present invention, those of ordinary skill in the art are not before making creative work
Every other embodiment obtained is put, shall fall within the protection scope of the present invention.
Embodiment 1
Object of the present invention is to require and low-alloy steel Q345R slab welding welding performance in analysis heavy gauge tube plate technique
On the basis of, it by verification experimental verification, finds and is suitable for big specification low-alloy steel Q345R tube sheet welding plate preparation process, realize
Big specification low-alloy steel Q345R tube sheet welding plate small deformation, high quality, economical and practical, high welding efficiency preparation.
After the completion of big specification low-alloy steel Q345R tube sheet welding, need to carry out surface processing, after processing flatness should be ±
Then 2mm drills, should control deflection during such welding, and the deflection for being used in the plate of the welding completion of tube sheet is got over
It is small better, it otherwise needs to guarantee finished product tube sheet design thickness size by increasing thickness direction allowance when disclosing, material will be increased
Material and processing cost；Control is deformed into the key of big specification low-alloy steel Q345R tube sheet welding plate preparation.It simultaneously should be
Under the premise of guaranteeing welding weldquality, big specification low-alloy steel tube sheet plate is completed using economic, efficient processing technology
Preparation, specific technical solution is as follows:
1) for low-alloy steel (Q345R) thick plates feature and end properties requirement, the welding material of selection is being passed through
After crossing whole process, there is good matching with base material.
Big specification low-alloy steel Q345R slab tube sheet plate welding, needs to carry out multi-pass welding and disappears for a long time
Stress heat treatment, thermal process can generate certain influence to the performance of weld seam, and welding material so used should ensure that more in multilayer
Joint performance after road welding heat process and subsequent long heat treatment is greater than or equal to base material, meets service performance requirement.Welding
In the process, argon arc welding and welding electrode arc welding are mainly bottoming and prevent burn-through, weld metal thickness entire weld seam accounting very
It is small, so mainly consider that the welding material of subsequent narrow-clearance submerged arc welding and tube sheet requirement performance match, so passes through mould
The test of quasi- tube sheet preparation process simulation test specimen selects and matches F48P2- in 1.5~1.9% high manganese welding wire containing alloying element manganese
H10Mn2 solder flux is as low-alloy steel Q345R slab welding welding material；
2) heavy gauge tube plate plate welding welding technique
Heavy gauge tube plate slab-thickness is big, using conventional buried arc welding method, needs using biggish bevel angle,
Guarantee the accessibility and the removability of slag of electric arc, welding quality is excellent, but processes that base material loss is big, and filling metal amount is big, Welder
Work amount increase, manufacturing cost increase；If using the mating narrow groove welding of conventional submerged arc soldering method, without lateral angle turning function,
Electric arc is parallel with side wall, and electric arc cannot cause weld seam and side wall incomplete fusion defect, while single track cladding gold with side wall good fusion
Belong to thickness to increase, submerged-arc welding welding bead and base material groove side wall form deep trouth, slag inclusion between subsequent welding will cause.According to existing weldering
Method is connect, between the single-filament narrow for selecting few welding efficiency height, consumption welding material, reliable welding quality, welding automatic welding degree high
Welding method of the gap submerged-arc welding as plate welding；
Heavy gauge tube plate welding, since welding is big with tube sheet sotck thinkness, intensity high rigidity is big, and the blank of welding itself
There are unevenness, orthopedic especially difficult to desired flatness ± 1mm, there are root faces after such welding heavy slab material retaining wall on slope
Not of uniform size, group will appear that root face height is different to after and group is to gap non-uniform phenomenon, weld after bottoming that there may be unmelted
It closes and lack of penetration phenomenon, arc-air gouging carbon consumes greatly, and the hot slag formed will cause damage to groove face, influence to weld
Tracking, carbon arc air gouging remove the carburized layer left after defect since grinding wheel or mechanical rubbing method curtailment can not be thoroughly clear
It removes, i.e., back chipping is difficult, and the welding quality of backing weld seam is difficult to ensure, and tube plate thickness is big, and defect removes heavy workload, and needs
Hot after being preheated, reclamation work amount is big.According to tube sheet welding plate blank material thickness combination welding method feature, selects and be easy in fact
Existing single face welding and double face shaping, the good argon tungsten-arc welding bottoming of Weld Performance and submerged-arc welding increase welding current and carry out back side back cover,
Since the welding penetration of submerged-arc welding is big, it is complete to be welded in backing weld seam using welding rod arc before submerged arc welding for burn-through in order to prevent
Thickened at rear progress weld metal, weld two layers, weld seam overall thickness reaches 8-10mm, then using single-filament narrow-gap submerged-arc welding into
The welding of welding weld seam is completed in row filling, capping.
3) big specification plate welding groove type and size
According to selected welding method, welding quality can be effectively ensured in consideration, weld industry takes into account production efficiency, choosing
With the trapezoidal root face of small end face, top is U-shaped double-U-shaped divided edge structure, and two sides groove depth differs the near symmetrical slope of 15mm
Mouth structure sets reasonable groove gap, and typical divided edge structure is as shown in rear attached drawing:
Root face is set as 2mm, and lower deviation is -0.5mm, and the upper deviation 0 guarantees bottoming through welding；
Root gap is set as 3mm, and lower deviation is -1mm, and the upper deviation is set as+2, guarantees bottoming root through welding；
Groove root sets bevel angle α=30 ° width 10mm, and holding root width is minimum 23mm, guarantees submerged arc welding
Mono- normal weld size of Shi Nengyou, will not be narrow due to groove width, was formed between bead thickness and groove side wall
Deep trench prevents the unilateral emersion and root through welding for forming too deep groove and being unfavorable for welding slag；
The U-shaped bevel angle in top is set as 10 °, and 5 ° of unilateral side sets lower deviation as -1 °, and the upper deviation is 0 °, keeps groove whole
Width controls between 34~37mm, on the one hand keeps the welding structure form of weld seam narrow gap, secondly increases one side weld and receives
Contracting amount is carried out weld industry while being reduced and turns over number raising production efficiency；
4) group pair of big specification jigsaw and station plate are reinforced
Two blocks of slab blanks for being used for welding tube sheet wait organize pair are placed on platform, size is wanted by above-mentioned groove group
It asks and is grouped, when adjustment groove size meets the requirements, in group to workpiece grooves both ends difference spot welding groove and workpiece to be welded
Groove is consistent, width 100mm, the run-on tab and arc-extinguishing plate of length 150mm, is used for the starting the arc and blow-out, prevents the starting the arc of submerged-arc welding
Defect is generated with blow-out；Secondly the Q345R transverse direction gusset for using 400 × 200 × 30mm of specification, perpendicular to groove length direction,
Vertical to be welded on group to good workpiece in shallow groove side, (reinforced weld is not less than away from groove back gauge for weld size 20mm × 45 °
50mm；Along entire one piece of the interval groove length direction 500mm), on the one hand secondly it is rigid to increase workpiece to groove size for fixed group
Property, non-deformability during welding plate welding is improved, the angular deformation amount when welding of deep groove side is reduced, increases deep groove side
Deposited metals thickness when welding improves weld metal intensity and crack resistance when Deformation control is turned over.
5) welding sequence and anti-deformation process technology
The every side 150mm of plate groove is faced from side back to be welded using four row's flame heating devices before tube sheet blank welding welding
Range is preheated, and the every side 300mm range of side slope mouth to be welded is kept the temperature using heat-preservation cotton, when the every side 100mm range temperature of groove
When degree reaches 80 DEG C or more, bottom welding is carried out from deep groove side using hand tungsten argon arc welding, then using stick electrode electricity
Arc-welding carries out thickening filling welding, welding rod E5015 specification Ф 4.0mm, and weld metal overall thickness reaches 8-10mm, and measurement groove is deep
Degree and groove width, measurement should uniformly measure at least five point in entire groove length, and make a record；
Using the alternately pressure road filling welding of single-filament narrow-gap submerged-arc welding bilateral, continuous welding until groove width reach 23~
When 25mm, stop welding, continues to keep heating, welding region temperature is kept to be not less than 80 DEG C, measure weld groove depth；It will be
The flat panel workpieces of welding are turned over；
Remove it is all rigidly fix station plate, select suitable welding parameter, using submerged-arc welding along Weld pipe mill carry out back cover
It welds, measures groove depth after back cover, and calculate weld metal thickness, make a record；
Using narrow-clearance submerged arc welding bilateral, alternately pressure road carries out back side filling welding, when welding groove width reaches 23~
When 25mm, groove depth thickness measuring is carried out, is made a record；
To be turned in weldering plate and carry out front deep groove side again and measure and weld, and so on ought work as groove width every time
When reaching 23~25mm, measurement records groove width and groove depth and makes a record, and tube sheet welding weld seam was welded entirely
Such front and back sides replace welding in journey；
When the deposited metals thickness of welding line reaches 50-55mm, pause welding, using the aluminum profile ruler of length 5m
The surface evenness measuring for carrying out welding plate welding side, when surface planarity reaches 4-5mm, tube sheet starts to turn over and be carried on the back
Weld seam filling welding in face so alternately replaces welding in measurement using long ruler, until the welding of single weld seam terminates.
6) hot after welding plate welding connector
After tube sheet welding weld seam welds, postwelding cooling velocity is too fast in order to prevent, and the hydrogen in weld seam has little time to escape
And brittle martensite tissue is formed, and after tube sheet welding weld seam welds, heat after needing to carry out weld dimensions, specifically
Measure are as follows: be laid with the electric crawler belt close-packed arrays of 300mm wide along fusion length direction, using heat-preservation cotton by the every side 500mm of weld seam
Range carries out local cladding, carries out weld seam temperature detection using four thermocouples, after weld seam is heated to 300 DEG C of heat preservations two hours
It is down to room temperature；
7) big specification plate welding weld seam non-destructive testing
Tube sheet is as main pressurized element, it is thus necessary to determine that excessive defect is not present in Seam and heat effected zone, otherwise will affect
The use of subsequent tube sheet；Weld seam detection can be used ray detection, ultrasound detection and diffraction time difference method ultrasound detection and carry out in weld seam
Portion's defects detection selects construction requirement simple by comparing, high to slab internal flaw Sensitivity, can be in production scene
It constructs and does not affect the normal production movable diffraction time difference ultrasound detection and carry out weld seam detection, and answered using ultrasound detection
Inspection, and Welded Joints surface carries out Magnetic testing, the implementation of specific detection method is carried out by NB/T47013, by the relevant technologies
It is required that carrying out an acceptance inspection；
8) big specification low-alloy steel jigsaw post weld heat treatment and anti-deformation control technology
In order to guarantee the dimensional stability in heavy gauge tube plate welding plate following process engineering and prevent welding point
Meta-stable tissue, which exists, causes subsequent defective, needs to carry out whole post weld heat treatment to the tube sheet that welding is completed, works as low-alloy steel
When welding tube sheet is heat-treated with plate, low-alloy steel material can be with the raising strength reduction of temperature, when yield strength is reduced to
When lower than welding stress, material is plastically deformed, and achievees the purpose that eliminate stress, but the rigidity of material reduces simultaneously, can be by
Gravity deforms, and the tube sheet for causing welding to be completed is changed with plate flatness, and should use when being so heat-treated must
Measure is wanted, prevents from causing tube plate deformation since the strength of materials rigidly reduces in heat treatment process.So take following measures: to
Heat treatment plate should be paved using I-steel, and channel steel height is not less than 300mm, channel steel length should than at pad slab length grow
At least 50mm, each channel steel spacing are not more than 1000mm, each channel steel are adjusted to same plane position after channel steel placement, then
Welding plate is placed on the channel steel of leveling, carries out the heat treatment of postwelding stress-removal by heat treatment process.
It elaborates below with reference to example to the present invention, it is specific as follows
1, big specification low-alloy steel welding tube sheet match welding material and Welding on Properties of Welding Joint requirement
1) the welding tube sheet following Tables 1 and 2 of low-alloy steel ingredient performance characteristics；
Table 1 welding tube sheet low-alloy steel Q345R ingredient and welding material chemical analysis
Table 2 is used for the mechanical property of tube sheet welding low-alloy steel Q345R
| Material trademark | Rp0.2(Mpa) | Rm(Mpa) | A% | Akv |
| Q345R | 470-600 | ≥265 | >=20% | ≥34J(0°) |
| ER50-6 | ≥420 | ≥500 | ≥22 | ≥54(-30℃) |
| E5015 | ≥400 | ≥490 | ≥20 | ≥54(-30℃) |
| F48P2-H10Mn2 | ≥400 | 480-600 | ≥22 | ≥36(-20℃) |
2) performance requirement of welding point
Welding point performance after post weld heat treatment meets the requirement of above-mentioned table 2；
2, the chemical component and mechanical property of actual tests material
Table 3 is used for the low-alloy steel Q345R and welding material chemical analysis of tube sheet welding
4 low-alloy steel Q345R base material of table and joint mechanical property
| Material trademark | Rp0.2(Mpa) | Rm(Mpa) | A% | Akv(-20℃) |
| Q345R | ≥265 | ≥515 | >=40% | ≥34(0℃) |
| Q345R | 350 | 534 | 26% | 64/86/39(-20℃) |
| ER50-6 | 434 | 594 | 32.0 | -129/139/157(-30℃) |
| E5015 | - | 614 | 38.5 | -146/149/150(-30℃) |
| F48P2-H10Mn2 | 430 | 535 | 30.5 | -112/127/138(-30℃) |
3, welding groove and group pair
The groove of the tube sheet welding low alloy steel plate of 170mm thickness is completed using machining, specific groove type form and
Then size, group carry out tack welding, fusion length 15- using argon arc welding to requiring to adjust groove size as shown in Figure 1:
25mm, it is vertical to be welded on group pair perpendicular to groove length direction using the Q345R transverse direction station plate of 400 × 200 × 30mm of specification
Good workpiece is in shallow groove side-reverse side, and (reinforced weld is not less than 50mm away from groove distance for weld size 20mm × 45 °；Along entire
One piece of the interval groove length direction 500mm).
5, it welds
5.1, welding technique
5.2, welding process sequence and Deformation control
The every side 150mm range of groove is preheated using four row's flame heating device reverse side before connecing, the every side of front groove
300mm range is kept the temperature using heat-preservation cotton, when the every side 100mm range temperature of groove reaches 80 DEG C or more, using manual tungsten
Electrode argon arc welding, welding wire ER50-6, Ф 2.4mm is from positive bottom welding, then carries out thickening filling weldering using stick electrode arc welding
It connects, welding rod E5015 specification Ф 4.0mm, when backing run reaches 8-10mm, measurement slope with the weld metal overall thickness for thickening welding bead
Mouth depth and groove width, measurement should uniformly measure at least five point in entire groove length, and make a record；
Using the alternately pressure road filling welding of single-filament narrow-gap submerged-arc welding bilateral, continuous welding until groove width reach 23~
When 25mm, stop welding, continues to keep heating, welding region temperature is kept to be not less than 80 DEG C, measure weld groove depth；It will be
The tube sheet workpiece of welding turns over；
Remove it is all rigidly fix station plate, select suitable welding parameter, using submerged-arc welding along Weld pipe mill carry out back cover
It welds, measures groove depth after back cover, and calculate weld metal thickness, make a record；
Using narrow-clearance submerged arc welding bilateral, alternately pressure road carries out back side filling welding, when welding groove width reaches 23~
When 25mm, groove depth thickness measuring is carried out, is made a record；
To be turned in weldering plate and carry out front deep groove side and weld, and so on ought every time when groove width reaches 23~
When 25mm, measurement records groove width and groove depth and makes a record, and plate welding weld seam is such in the whole welding process
Front and back sides replace welding；
When the deposited metals thickness of welding line reaches 50-55mm, pause welding, using the aluminum profile ruler of length 5m
The surface evenness measuring for carrying out welding plate welding side, when surface planarity reaches 4-5mm, welding plate start to turn over into
The filling welding of row sealing run so alternately replaces welding in measurement using long ruler, until the welding of single weld seam terminates.
6, hot after welding plate welding connector
After tube sheet welding weld seam welds, the electric crawler belt close-packed arrays of 300mm wide are laid with along fusion length direction, are adopted
The every side 500mm range of weld seam is subjected to local cladding with heat-preservation cotton, weld seam temperature detection is carried out using four thermocouples, by weld seam
Room temperature is down to after being heated to 300 DEG C of heat preservations two hours；
7, big specification plate welding weld seam non-destructive testing
After the completion of welding and rear heat, is carried out non-destructive testing using diffraction time difference supersonic testing method Welded Joints, work as presence
When defect, reinspection confirmation defective locations and size are carried out using ultrasound detection, surface carries out detection qualification using magnetic powder, specific to examine
The implementation of survey method is carried out by NB/T47013, is carried out an acceptance inspection by associated specifications；
8, big specification low-alloy steel jigsaw post weld heat treatment and anti-deformation control technology
It is heat-treated placement platform, channel steel height 300mm in the preparation heavy gauge tube plate furnace of welding plate, channel steel length is answered
At least 50mm is grown than welding slab length at institute's pad, each channel steel spacing is not more than 1000mm, by each slot after channel steel placement
Steel is adjusted to same plane position, and then plate is placed on the channel steel of leveling, and specific heat treatment process is as shown in Fig. 2.
Carries out with plate the mechanics properties testing of apparent size and test plate (panel) to the welding heavy gauge tube plate that heat treatment is completed, it is flat
For plate surface flatness within the scope of ± 5mm, welding plate weld seam has slag inclusion excessive defect at two to be reprocessed, the lossless inspection of weld seam
Mass metering meets technical requirements, and institute's band welding sample together with welding plate after the completion of being heat-treated when to tube sheet plate welding
Preparation stretches, and bending and impact specimen carry out every test, and experimental performance is met the requirements.
In summary: a kind of big specification low-alloy steel tube sheet welding plate preparation process provided by the invention, it can be effective
Raising directly is reduced, reduces tooling processing cost, welding material expenditure is few, and technical process is simple and easy, strong operability；It is welded
Good quality is stitched, surface smoothness meets the welding plate of tube sheet processing request；
Finally, it should be noted that the foregoing is only a preferred embodiment of the present invention, it is not intended to restrict the invention,
Although the present invention is described in detail referring to the foregoing embodiments, for those skilled in the art, still may be used
To modify the technical solutions described in the foregoing embodiments or equivalent replacement of some of the technical features,
All within the spirits and principles of the present invention, any modification, equivalent replacement, improvement and so on should be included in of the invention
Within protection scope.
Claims (8)
1. a kind of big specification low-alloy steel tube sheet welding plate preparation process, characterized by the following steps:
S1, big specification low-alloy steel welding tube sheet match welding material selection,
According to the base material performance requirement of heavy gauge tube plate, selecting thickness is more than the plate of 80mm and base material with the trade mark, selects alloy
Element manganese welds material as low-alloy steel Q345R slab welding with F48P2-H10Mn2 solder flux in 1.5~1.9% high manganese welding wire
Material；
S2, heavy gauge tube plate are welded with plate welding
By argon tungsten-arc welding bottoming, welding electrode arc welding root thickens welding, recycles efficient single-filament narrow-gap submerged-arc welding filling
Weld seam is completed in cover welding；
S3, big specification plate welding groove type
Using double U-groove, it is easily guaranteed that root through welding and is conducive to the big specification by Control Welding Process welding deformation
Plate welding groove；
S4, the group pair of big specification jigsaw and station plate are reinforced,
Two block parts wait organize pair are placed on platform, are grouped, groove size is adjusted, in group to workpiece grooves both ends point
Other spot welding groove run-on tab consistent with workpiece grooves to be welded and arc-extinguishing plate increase vertical at the back side for first welding groove of double grooves to be welded
Positioning group to weld size and is improved the rigidity of welding tube sheet, enhances welding process by formula and base material with the lateral gusset of intensity
Middle non-deformability guarantees weldquality and prevents the generation of tearing during turning over；
S5, welding sequence and anti-deformation
Basic welding sequence is: before preheating-bottom argon arc welding welding-welding electrode arc welding thickens welding-narrow-clearance submerged arc welding weldering
Groove width depth dimensions measurement-single-filament narrow-gap submerged-arc welding bilateral alternately presses road welding-welding process groove width depth
Measurement-welding plate turn-narrow-clearance submerged arc welding back cover weld-measures groove depth width-determines weld metal thickness
Degree-back side filling welding-measurement groove width and depth-welding plate turn over, and so on, when deposited metals thickness reaches
When to 50-55mm, the surface evenness measuring of welding plate is carried out using the aluminum profile ruler of length 5m, when surface planarity etc.
Jigsaw, which starts to turn over, when 4-5mm carries out sealing run filling welding, and the above welding process is continuously finished, until welding terminates；
It is hot after S6, welding plate welding connector
After the completion of needing to stop welding or the welding of whole weld seam in welding process, using axis of a weld as axis, using electric heating
The electric crawler belt close-packed arrays of 300mm wide are laid with by crawler belt along fusion length direction, and heat-preservation cotton carries out the every side 500mm range of weld seam
Part cladding carries out weld seam temperature detection using four thermocouples, and weld dimensions are heated to 300 DEG C and keep the temperature two hours
After be down to room temperature；
S7, big specification plate welding weld seam non-destructive testing
It is detected using diffraction time difference method supersonic detection method, and is detected and checked and accepted as requested；
S8, big specification low-alloy steel jigsaw post weld heat treatment and anti-deformation control
Specification welding plate enters furnace treatment reason mode to the progress post weld heat treatment of welding connector using entirety greatly, and welding is used to manage
Before the plate heat treatment of plate, heat treatment tooling platform is prepared using I-steel, the channel steel height being used to support is not less than 300mm,
Channel steel length should than at pad plate grow at least 50mm, each channel steel spacing is not more than 1000mm, and channel steel will be each after placing
Channel steel is adjusted to same plane, and the good big specification low-alloy steel plate of welding is placed on the channel steel tooling platform of leveling, is pressed
Heat treatment process carries out the heat treatment of postwelding stress-removal, completes the preparation of heavy gauge tube plate welding plate.
2. a kind of big specification low-alloy steel tube sheet welding plate preparation process according to claim 1, it is characterised in that:
In S2, selection is easy to guarantee weldquality, guarantees through welding and prevents burn-through, can reduce loss, the welding procedure improved efficiency
Method uses bottom argon arc welding, welding electrode arc welding thickens, narrow-clearance submerged arc welding filling, back cover, capping welding procedure side
Formula.
3. a kind of big specification low-alloy steel tube sheet welding plate preparation process according to claim 1, it is characterised in that:
In S3, big specification low-alloy steel tube sheet plate welding, it is ensured that weldquality and plate welding surface irregularity, according to choosing
Fixed welding technique needs to design the small root face to match with welding technique, low-angle, two-sided U similar in groove depth
Type divided edge structure.
4. a kind of big specification low-alloy steel tube sheet welding plate preparation process according to claim 1, it is characterised in that:
In S4, big specification low-alloy steel tube sheet plate welding needs to prevent the groove for meeting welding requirements by technique requirement group
Misalignment and gap are excessive；The receipts arc arc-extinguishing plate of certain length is respectively set in the starting and ending of weld to be welded, makes submerged arc
The issuable defect of receipts expulsion of arc arc of weldering will not stay in production joint；Underside groove in the groove side of welding first increases
Lateral stiffness station plate, it is ensured that groove group increases weldment rigidity to dimensionally stable when welding, increases initial stage welding groove side filling gold
Belong to metal thickness, guarantees that weld seam has the intensity for preventing tearing when turning over.
5. a kind of big specification low-alloy steel tube sheet welding plate preparation process according to claim 1, it is characterised in that:
In S5, big specification low-alloy steel jigsaw is using narrow gap after preheating, bottom argon arc welding and stick electrode arc welding thicken
During submerged arc welding, need to be turned over welding by specifying measurement groove width and depth, then measured groove width and depth again
Degree turns over welding, so two-sided alternately to weld, and controls welding deformation using the deformation rule in welding process, when weld seam gold
Category reaches certain thickness, then carries out surface planarity measurement using ruler, turns over welding, measures surface planarity, so two-sided
It alternately welds, completes tube sheet plate welding, form the satisfactory tube sheet plate of surface smoothness.
6. a kind of big specification low-alloy steel tube sheet welding plate preparation process according to claim 1, it is characterised in that:
In S6, after the completion of the plate welding of big specification low-alloy steel tube sheet, the big cooling velocity of slab-thickness is fast, cannot be heat-treated immediately
Improve tissue and stress state, need to carry out heat after postwelding, rear thermal recovery is carried out with local heating mode, crawler belt heater is pressed
Regulation welding point both sides carry out be laid with and and with heat-preservation cotton it is coated, be heated to 300 DEG C heat preservations 2 hours, make the hydrogen in weld seam
It is able to sufficiently spread evolution, prevents cold crack.
7. a kind of big specification low-alloy steel tube sheet welding plate preparation process according to claim 1, it is characterised in that:
In S7, whether confirmation heavy gauge tube plate plate welding weld seam meets requirement, and use is radiationless, to heavy wall workpiece, defect
Detection sensitivity is high, and the simple diffraction time difference method ultrasound detection internal soundness detection of auxiliary material, it is fixed that ultrasound detection carries out defect
Position, magnetic powder carry out surface defects detection, it is ensured that quality of weld joint meets the requirements.
8. a kind of big specification low-alloy steel tube sheet welding plate preparation process according to claim 1, it is characterised in that:
In S8, big specification low-alloy steel welding plate postwelding carries out stress-removal heat treatment, generates except welding point welding rapid cooling is eliminated
Brittlement phase, reduce welding point peak stress, guarantee tubesheet dimension stability and weldquality requirement, it is also necessary to using heat at
Anti-deformation measure is managed, keeps welding planar surface smooth, realizes that the big specification low alloy steel plate that welding is completed is heat-treated rear surface
Flatness meets the needs of tube sheet processing in the requirement of ± 5mm range.
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| CN110977356A (en) * | 2019-12-23 | 2020-04-10 | 中国电建集团长春发电设备有限公司 | Method for manufacturing rear wheel disc of striking wheel of light fan coal mill |
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| CN114749764A (en) * | 2022-04-28 | 2022-07-15 | 鞍钢股份有限公司 | Stainless steel and carbon steel narrow gap gas shield welding process |
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