X70 of our country large requirements is defeated by gas steel tube to solder technology and quality current situation

6~21.

The welding line property that the homebred X70 cop of 0mm manages reachs quite high level, especially the summer of welding line pounds function than V breach low temperature. The article carries many survey, count, analysed what at present X70 cop steeliness runs our country to solder technology and quality current situation. Keyword: X70 carries steel tube to solder technical quality preface is enraged on the west east be defeated by a project is new century begins a big major project of our country. Conduit makes an appointment with 4000km endlong, initial stage is defeated by tolerance to be annual 12 billion stere, be defeated by tolerance finally annual 20 billion stere. Design pressure 14MPa, moving pressure 10MPa, steel tube dosage makes an appointment with many tons 160. She carries the natural gas resource western economy to develop but the southeast foreland that the sources of energy is in short supply, the economy that promotes big earth China grows, and the progress that drove duct of natural gas of our country oil to make tubal technology. X70 is the steel of cop of high strenth of a kind of microalloy that the development at the beginning of 70 time of foreign rises, use accuse make friends to accuse cold craft, get with acicular the organization that ferrite gives priority to, the function such as intensity, tenacity and weldability is first-rate, a large number of use already was in in the project, the technology is very mature already. The application of steel of our country cop considers to start later, develop however very fast, a3F, 16Mn is used all the time before 80 time a kind rolled steel, till the later period in 80 time just begins a few adoption X60 steel tube, and it is import rolled steel more. Begin at the beginning of 80 time, the domestic steely company, factory that make a valve and scientific research unit pass old effort, development goes steel of cop of X60, X65. For the country enrage on the west east the need that is defeated by project, gave steel of cop of X70 high strenth at was being developed again 2001. [1] [4] oil gas carries steel tube solder, it is one of crucial technology segment of the factory that make a valve, solder the actors or actress bad matters to cop to move safety of quality, can measure steel of cop of a country to solder technical level. In the process that develops steel tube of large requirements X70, tackle key problem the unit gave very great effort, captured a lot of technology difficulty, mastered X70 cop steel to solder technology, developed large requirements 2002 at was being mixed 2001 in succession (OD.

1016mm) X70 helix buries arc solder to be in charge of (SSAW) and seam the solder that bury arc to be in charge of continuously (LSAW) , make an appointment with canal of 800 thousand tons homebred X70 solder to be used at the country enrage on the west east be defeated by project, manufacturing solder is in charge of percent of pass to achieve 97 ％ above. The article carries many survey, count, the analysis studied what at present X70 cop steeliness runs our country to solder technology and quality current situation. 1 welder art enrage on the west east the external diameter that is defeated by a project to use steel tube all is 1016mm, and what basis of steel tube ply uses area category is different from 14.

6 to 26.

2mm. This project uses steel tube cent to seam steel tube of the solder that bury arc with helix to be seamed continuously two kinds, as a result of historical reason, the steel tube product line of our country is product line of spiral coil cooling tube mostly, participate in enrage on the west east the yard of spiral coil cooling tube that loses production of project steel tube has 6, all be online solder. To be enraged on the west east the need that is defeated by a project, mill of among them a pipe built to seam the solder that bury arc to provide product line continuously, shape means is JCOE. Of the steel tube that make solder the method all is used double-faced the solder that bury arc, solder the manufacturing welder that equipment is American Lincoln or German Messer company. According to material ply different, solder of steel tube inside and outside is used commonly 2 - 4 solder, also path of the solder inside individual manufacturer uses monofilament solder. Helix buries arc solder canal to use online solder, because be gone by forming machine group,take the restriction of speed, solder rate is not high, and the solder that straight seam welding is in charge of fast taller. The welder that home produces φ 1016mm X70 to bury arc solder to be in charge of art see a table 1, solder through controlling solder wiring energy to assure steel tube the function of contact. Normal Align=center> watch buries arc solder canal to basically solder craft parameter Normal Align=center>Table 1 The Primary Welding Procedure Parameter Of O.

D1016mm X70 SAW Pipenormal LINE-HEIGHT of Center" Align=center> wall: 10pt; TEXT-ALIGN: Normal Align=center> steel tube: 10pt; TEXT-ALIGN: Center" Align=center> phyletic Normal Align=center> solders Normal LINE-HEIGHT of groove of Center" Align=center> method: 10pt; TEXT-ALIGN: Normal Align=center> form: 10pt; TEXT-ALIGN: Normal Align=center> welding wire: 10pt; TEXT-ALIGN: Center" Align=center> solders speed Normal Align=center>v ／ (Mm · Min-1) Normal LINE-HEIGHT of energy of wiring of Center" Align=center> solder: 10pt; TEXT-ALIGN: Center" Align=center>E ／ (KJ · Cm-1) Normal LINE-HEIGHT of path of the solder inside Center" Align=center> : 10pt; TEXT-ALIGN: Normal Align=center> : 10pt; TEXT-ALIGN: Center" Align=center>14.

6 Normal Align=center>SSAW Normal Align=center> buries arc solder Normal Align=center>Y Normal Align=center>1 or 2 Normal Align=center>2 Normal Align=center>~1200 Normal LINE-HEIGHT of Center" Align=center> ～ : 10pt; TEXT-ALIGN: Center" Align=center>17.

5 Normal Align=center>LSAW buries arc solder Normal Align=center>X Normal Align=center>4 Normal Align=center>4 Normal Align=center>~1800 Normal LINE-HEIGHT of Center" Align=center> ～ : 10pt; TEXT-ALIGN: Center" Align=center>21.

0 Normal Align=center>LSAW Normal Align=center> buries arc solder Normal Align=center>X 4 Normal Align=center>4 Normal Align=center>~1600 Normal LINE-HEIGHT of Center" Align=center> ～ : 14pt">2 solders material Normal > steel tube that make solders material includes to bury arc welding wire and welding flux. The welding wire that uses at present basically is H08C, this is a country " 85 " the steel of cop of high strenth tall tenacity that develops about the unit during the plan is special welding wire, belonging to Mo-B-Ti alloy is, it is the high grade welding wire of content of phosphor of a kind of low carbon, low sulfur, low gas and matter content. Through using microalloy to change He Xijing bead strong pliable but strong changes mechanism to design welding wire, make welding line got with acicular the organization that F gives priority to, satisfy the requirement of high strenth and tall tenacity at the same time. Its typical chemical composition and mechanical sex visibility are expressed 2, watch 3. The typical metallographic organization that uses this welding wire to produce steel tube welding line sees a picture 1. Also some factories that make a valve use JW - the welding wire of 9 brands, it and H08C welding wire have the chemical composition of close and mechanical property. [2] Normal > uses has 2 kinds, the brand is SJ101 and SJ101G respectively, all be domestic production. SJ101 welding flux belongs to fluorine alkaline model agglomeration welding flux, alkalinity value is 1.

8 the left and right sides, granuality 60 eye of 10 ～ , welding flux composition is Ti-Al2O3-MgO system. This welding flux is had fight sex suction tide goodly, solder it is stability of combustion of process electric arc, easy to take off broken bits, the microtherm concussion tenacity of metal of place solder welding line is taller. SJ101G welding flux also belongs to fluorine alkaline model agglomeration welding flux, alkalinity value is 1.

6~2.

0, for fluorine alkaline model broken bits fastens a feature, composition of solder broken bits: 15 ％ of 20 ％ of 50 ％ of ≥ of CaO+MgO+MnO ＋ CaF2, SiO2 ≤ , CaF2 ≥ , get tall tenacity welding line through cooperating H08C welding wire. [3] Normal Align=center> watch (Wt% ) Normal Align=center>Table 2 The Typical Chemical Analysis Of H08C Wire (Wt% ) Normal Align=center>C Normal Align=center>Si Normal Align=center>Mn Normal Align=center>P Normal Align=center>S Normal Align=center>Mo Normal Align=center>Ti Normal Align=center>B Normal Align=center>Cr+ Ni+Cu Normal Align=center>0.

086 Normal Align=center>0.

18 Normal Align=center>1.

54 Normal Align=center>0.

020 Normal Align=center>0.

0015 Normal Align=center>0.

32 Normal Align=center>0.

030 Normal Align=center>0.

0048 Normal Align=center>0.

080 Normal MARGIN-TOP of typical and mechanical function of metal of apply of frit of welding wire of 3 H08C of Center" Align=center> watch: 2.

5pt; LINE-HEIGHT: 10pt; TEXT-ALIGN: The function Normal Align=center> form a complete set: 2.

5pt; LINE-HEIGHT: 10pt; TEXT-ALIGN: Normal Align=center> tensile strength: 2.

5pt; LINE-HEIGHT: 10pt; TEXT-ALIGN: ／ of B of Center" Align=center> σ (MPa) Normal Align=center> succumbs intensity Normal Align=center> σ (MPa) Normal Align=center>-20 ℃ pounds result Normal Align=center>CVN ／ (J) Normal Align=center>SJ101G Normal Align=center>638 Normal Align=center>523 175 Normal >3 solders quality Normal >3.

Normal > welding line includes welding line, bad side, welding line and mother capable person transfer, uniformity of welding line appearance, size is waited a moment. Graph the 2 helix that are a group of models are seamed with seam the solder that bury arc to provide contrast of quality of welding line exterior continuously. With seam the solder that bury arc to be in charge of photograph of quality of welding line exterior to compare continuously, helix buries arc solder to because be online,be in charge of solder, solder to affect and cannot adjust what craft gets forming machine group groove, the exterior quality of welding line is general and bad, expression transfers in welding line and mother capable person the shape of a saddle-a falling-off between two peak periods of not pliable, welding line, Yu Gao is exorbitant etc, this pair solders of contact bear the weight of have bigger effect, this is one of respects that canal of homebred helix solder needs hard to improve. Normal >3.

2 welding line are immanent quality Normal > welding line shows welding line is whole quality, namely of welding line flawless quality. Flaw detection percent of pass can measure welding line standard of this one quality. This project is homebred steel tube welding line flaw detection percent of pass, helix seams canal of the solder that bury arc to make an appointment with 75 ％ commonly, seam canal of the solder that bury arc to make an appointment with 85 ％ commonly continuously. The blemish of welding line basically is not solder is appeared, slag inclusion, bad side. Visible, welding line flaw detection percent of pass is not tall, equivalent steel tube need is repaired through soldering will satisfy technical condition to ask, filling solder becomes the miller that make a valve to want one of jobs. Normal > is in charge of a factory to produce the reason with unqualified steel tube to undertake analytic statistic to home, the unqualified helix that because weld defects is caused,shows as a result seams canal of the solder that bury arc to occupy 50 ～ 60 ％ , seam canal of the solder that bury arc to occupy month of 45 ％ continuously. Visible, solder immanent quality problem is to cause the main reason with unqualified steel tube, this is another respect that quality of homebred solder canal needs to improve. Normal Align=center> pursues the typical metallographic of welding line of 1 steel tube organizes Normal Align=center>Fig.

1The Typical Welds Microstructure Of Pipes pursues 2 helix seam with seam the solder that bury arc to be in charge of Normal Align=center>Fig.

2The Typical Welds Appearance Of SSAW And LSAW Line Pipes Normal >3.

The mechanical function Normal >X70 steel tube can be passed is drawing, summer comparing the test data such as concussion, hardness will measure. Watch 4 listed factory of a few main steel tube of domestic is enrage on the west east the X70 steel tube that loses project production solders the main function of contact, for contrast, the X70 steel tube that listed period of some of factory of Japanese some steel tube is produced for this project at the same time solders the main function of contact. Homebred steel tube solders the tensile strength of contact satisfies technical condition to ask (≥ 570MPa) , average is apparently taller than importing steel tube. Welding line of homebred steel tube and the hardness that heat up influence area satisfy technical condition to ask (Hv10 ≤ 270) , average moderate. Normal Align=left> steel tube is high pressure of tall steel class cop transporting gas a very main index, from the watch 4 can see, welding line of homebred steel tube and the concussion result that heat up influence area and photograph of entrance steel tube are more coequal than be in level, average is very tall, but the concussion result that exists to measure steel tube welding line rarely asks under technical condition (- 20 ℃ summer compares concussion result 3 sample average is not less than 90J, individual sample lowest is worth the phenomenon that is not less than 60J) . Graph 3 it is homebred qualification summer of steel tube welding line compares concussion result (- 20 ℃ ) odds distributinging graph, can see, besides 17.

5mmOutside LSAW steel tube (the odds of 120J above steel tube makes an appointment with 80 ％ ) , the summer of steel tube of 90 ％ above is in than concussion result 120J above. Series temperature pounds test data to also make clear, welding line metal has good microtherm change character. It is thus clear that welding line of homebred steel tube has good concussion performance, but the stability need of tenacity of steel tube welding line rises further. Normal Align=center> expresses 4 enrage on the west east the X70 steel tube that is defeated by a project to produce domestic and internationally solders the Normal Align=center>Table 4 Main Welds Mechanical Property Data Of Pipes For The Projectnormal LINE-HEIGHT of factory of Center" Align=center> steel tube: 10pt; TEXT-ALIGN: Normal Align=center> steel tube: 10pt; TEXT-ALIGN: Normal Align=center> norms: 10pt; TEXT-ALIGN: Center" Align=center> (Mm) Normal LINE-HEIGHT of Center" Align=center> steel tube: 10pt; TEXT-ALIGN: Normal Align=center> type: 10pt; TEXT-ALIGN: Normal Align=center> connect: 10pt; TEXT-ALIGN: B / of Center" Align=center> σ (MPa) Normal Align=center> - 20 ℃ Xia Bichong attacks result CVN/ (J) Normal LINE-HEIGHT of Center" Align=center> hardness: 10pt; TEXT-ALIGN: Normal Align=center> welding line: 10pt; TEXT-ALIGN: Center" Align=center>HAZ Normal LINE-HEIGHT of Center" Align=center> welding line: 10pt; TEXT-ALIGN: Center" Align=center>HAZ Normal Align=center>Min Normal Align=center>Max Normal Align=center>Ave Normal Align=center>Min Normal Align=center>Max Normal Align=center>Ave Normal Align=center>Min Normal Align=center>Max Normal Align=center>Ave Normal Align=center>Max Normal Align=center>Ave Normal Align=center>Max Normal Align=center>Ave Normal LINE-HEIGHT of factory of steel tube of B of Center" Align=center> home: 10pt; TEXT-ALIGN: 1016 × of Center" Align=center> φ 14.

6 Normal Align=center>SSAW Normal Align=center>655 Normal Align=center>785 Normal Align=center>726 Normal Align=center>50 Normal Align=center>278 Normal Align=center>161 Normal Align=center>52 Normal Align=center>340 Normal Align=center>235 Normal Align=center>264 Normal Align=center>228 Normal Align=center>255 Normal Align=center>213 Normal LINE-HEIGHT of factory of steel tube of H of Center" Align=center> home: 10pt; TEXT-ALIGN: 1016 × of Center" Align=center> φ 14.

6 Normal Align=center>SSAW Normal Align=center>635 Normal Align=center>755 Normal Align=center>727 Normal Align=center>60 Normal Align=center>289 Normal Align=center>185 Normal Align=center>32 Normal Align=center>443 Normal Align=center>247 Normal Align=center>268 Normal Align=center>232 Normal Align=center>268 Normal Align=center>222 Normal LINE-HEIGHT of factory of steel tube of L of Center" Align=center> home: 10pt; TEXT-ALIGN: 1016 × of Center" Align=center> φ 14.

6 Normal Align=center>SSAW Normal Align=center>620 Normal Align=center>750 Normal Align=center>700 Normal Align=center>43 Normal Align=center>276 Normal Align=center>152 Normal Align=center>31 Normal Align=center>396 Normal Align=center>272 Normal Align=center>266 Normal Align=center>241 Normal Align=center>264 Normal Align=center>230 Normal LINE-HEIGHT of factory of steel tube of J of Center" Align=center> home: 10pt; TEXT-ALIGN: 1016 × of Center" Align=center> φ 17.

5 Normal Align=center>LSAW Normal Align=center>595 Normal Align=center>755 Normal Align=center>680 Normal Align=center>33 Normal Align=center>252 Normal Align=center>143 Normal Align=center>63 Normal Align=center>345 Normal Align=center>251 Normal Align=center>268 Normal Align=center>228 Normal Align=center>262 Normal Align=center>211 Normal LINE-HEIGHT of factory of steel tube of J of Center" Align=center> home: 10pt; TEXT-ALIGN: 1016 × of Center" Align=center> φ 21.

0 Normal Align=center>LSAW Normal Align=center>615 Normal Align=center>775 Normal Align=center>688 Normal Align=center>80 Normal Align=center>250 Normal Align=center>173 Normal Align=center>122 Normal Align=center>343 Normal Align=center>246 Normal Align=center>258 Normal Align=center>220 Normal Align=center>245 Normal Align=center>204 Normal LINE-HEIGHT of factory of steel tube of Z of Center" Align=center> Japan: 10pt; TEXT-ALIGN: 1016 × of Center" Align=center> φ 14.

6 Normal Align=center>LSAW Normal Align=center>610 Normal Align=center>634 Normal Align=center>623 Normal Align=center>145 Normal Align=center>230 Normal Align=center>195 Normal Align=center>250 Normal Align=center>312 Normal Align=center>280 Normal Align=center>228 Normal Align=center>214 Normal Align=center>218 Normal Align=center>196 Normal LINE-HEIGHT of factory of steel tube of Z of Center" Align=center> Japan: 10pt; TEXT-ALIGN: 1016 × of Center" Align=center> φ 21.

0 Normal Align=center>LSAW Normal Align=center>612 Normal Align=center>650 Normal Align=center>629 Normal Align=center>66 Normal Align=center>248 Normal Align=center>196 Normal Align=center>188 Normal Align=center>452 Normal Align=center>276 Normal Align=center>221 Normal Align=center>210 Normal Align=center>240 Normal Align=center>229 Normal Align=left>3.

4 solder leftover stress Normal Align=left> is well-known, leftover stress has very big effect to structural carrying capacity, method of traditional leftover stress test is very complex, carry out in actual project it is more difficult to rise, it is such more to production of big batch of cop steel tube especially. Enrage on the west east be defeated by regulation of project technology condition, the valve that takes length to be more than 100mm is cut on steel tube paragraph, be apart from welding line 100mm to be in edge axial incision, the leftover stress that judges solder canal secondhand through measuring cut axial to stretch a quantity to come. The bulk of leftover stress can come through built experience formula estimation. This is a kind of simple, easy travel, compare intuitionistic solder to be in charge of leftover stress to check a method again. Measured value is solder and shape the comprehensive report of quality, a large number of use already was in in the project. [5] Normal Align=left> as a whole, seam the solder that bury arc to because undertook enlarge diameter is handled after solder,be in charge of continuously, leftover stress is very little, helix seams the solder that bury arc to manage leftover stress bigger. But helix buries arc solder to tubal course shapes and solder craft is improved, the measure such as compression test, can make its remains stress is reduced substantially. This project stretchs a quantity to be commonly under 50mm with the cut that seams canal of the solder that bury arc continuously, great majority is controlled in 20mm, helix buries arc solder to be in charge of annulus to cut the 80mm range that opens a quantity to assure basically to set in technical condition. Visible, the standard of overall and leftover stress that helix buries arc solder to be in charge of is relative taller, this is helix buries arc solder to be in charge of what need improves on the other hand. Graph the photograph of the 4 sample cutting link that bury arc solder canal for a group of helix. A) 14.

6mmSSAW is in charge of B) 17.

5 with 21.

0mmSummer of welding line of steel tube of ℃ of 3 -20 of LSAW canal graph compares distributinging Fig of concussion result odds.

320 ℃ of – of Pipe Welds Charpy Impact Energy (at) Probability Distributionnormal Align=center> graph Normal Align=center>Fig.

4The Picture Of SSAW Pipes Stress Cut-ring Testnormal >4 epilogue Normal > is passed enrage on the west east those who be defeated by a project drive, our country developed helix of class of Gao Gang of large requirements X70 successfully to bury arc solder steel tube and seam steel tube of the solder that bury arc continuously. Pass large quantities of quantities to produce, each made tubal mill master its basically already to solder technology, steel tube solders the function of contact, especially the microtherm concussion tenacity of welding line reached foreign advanced level. But, in some way, if welding line is exterior quality, immanent,the respect such as level of quality, leftover stress remains to be improved further rise. CNC Milling