挤压量是指管坯边缘经过高频加热后通过挤压辊时焊缝处金属的挤压量，挤压量的简便测量是焊接前后圆周长度之差。

Extrusionamountreferstotheextrusionamountoftheweldmetalwhentheedgeofthetubebilletpassesthroughtheextrusionrollerafterhighfrequencyheating.Thesimplemeasurementofextrusionamountisthedifferenceofthecircumferentiallengthbeforeandafterwelding.

挤压量和输入热量一样，是影响焊接质量的重要因素之一，适当的挤压量可以增大被焊金属的接触面，使足够的金属颗粒产生晶间作用，影响焊接压力的大小，影响金属流线上升角的大小，从而影响焊接强度。

Extrusionamountisoneoftheimportantfactorsaffectingtheweldingquality,justliketheheatinput.Appropriateextrusionamountcanincreasethecontactsurfaceofthemetaltobewelded,makeenoughmetalparticlesproduceintergranularinteraction,affectthesizeofweldingpressure,affectthesizeofmetalstreamlinerisingangle,andthusaffecttheweldingstrength.

挤压量小，允许输入热量的范围窄，热影响区宽度大，金属流线上升角小，焊接质量不稳定，易出现咬边、夹杂物（黑色过烧氧化物）、顶弧（白色过烧氧化物）、熔合不足等焊接缺陷，适当增大挤压量使允许输入热量的范围变窄，减小热影响区宽度，增加金属流线上升角，增加焊接质量，但当挤压量过大时，不但降低了焊接强度，而且增加了内外毛刺的量，使得塑性高的边缘面上的金属挤压出焊缝，造成清除困难，由于温度低，熔合线上金属颗粒的分子扩散能力减弱，影响固相再结晶过程，容易造成搭焊缺陷。

Theweldingqualityisunstable,andtheweldingdefectssuchasundercut,inclusion(blackoverburnedoxide),toparc(whiteoverburnedoxide)andinsufficientfusionareeasytoappear.Increasingtheextrusionamountappropriatelynarrowstherangeofallowableheatinput,reducesthewidthofheataffectedzoneandincreasesthemetalflowHowever,whentheextrusionamountistoolarge,itnotonlyreducestheweldingstrength,butalsoincreasestheamountofinternalandexternalburr,whichmakesthemetalontheedgesurfacewithhighplasticityextrudeoutoftheweld,resultingindifficultremoval.Duetothelowtemperature,themoleculardiffusionabilityofthemetalparticlesonthefusionlineisweakened,whichaffectsthesolidphaserecrystallizationprocess,andiseasytocauseweldingdefects.

在输入热量不变的情况下，热影响区宽度和熔合线宽度随着挤压量的增加而减小，同时允许输入热量的范围随挤压量的减小而减小，随着挤压量的增加而增大，当挤出量小于0.5mm时，允许输入热量的范围很窄，当挤压量为1.5mm时，允许输入的热量范围较宽，当挤压量大于2.0mm时，允许输入热量范围的增加表现得不明显。

Whentheheatinputisconstant,thewidthofheataffectedzoneandthewidthoffusionlinedecreasewiththeincreaseofextrusionamount,andtherangeofallowableheatinputdecreaseswiththedecreaseofextrusionamount,andincreaseswiththeincreaseofextrusionamount.Whentheextrusionamountislessthan0.Whentheextrusionamountis1.5mm,therangeofallowableheatinputisverynarrow.Whentheextrusionamountismorethan2mm,theallowableheatinputrangeiswide.Whenthetemperatureislessthan0mm,theincreaseofallowableheatinputrangeisnotobvious.

因此，在实际生产中，应充分考虑壁厚，挤出量控制在2.0~3.0毫米为宜，对于厚壁管如8mm以上的焊管，挤出量可适当增加1~2毫米，当焊管强度较高时，挤出量也应适当增加，经验上挤压量常按壁厚的40％~50％计算。

Therefore,intheactualproduction,thewallthicknessshouldbefullyconsidered,andtheextrusionamountshouldbecontrolledat2.0~3.0mm.Forthickwallpipesuchasweldedpipeover8mm,theextrusionamountcanbeincreasedby1~2mm.Whentheweldedpipestrengthishigh,theextrusionamountshouldalsobeincreased.Inexperience,theextrusionamountisusuallycalculatedas40%~50%ofthewallthickness.

焊接温度对焊接质量的影响

Influenceofweldingtemperatureonweldingquality

焊接温度应控制在℃~℃，在实际生产中，通过观察火焰颜色和毛刺形状来判断和调整焊接温度的适宜度，在刚出挤压辊时，正常焊缝的颜色为桔红色，如果温度太高，颜色是红白相间，如果温度太低，颜色是暗红色。

Theweldingtemperatureshouldbecontrolledat℃~℃.Inactualproduction,thesuitabilityofweldingtemperaturecanbejudgedandadjustedbyobservingtheflamecolorandburrshape.Whentheextrusionrollisjustout,thecolorofnormalweldisorangered.Ifthetemperatureistoohigh,thecolorisredandwhite.Ifthetemperatureistoolow,thecolorisdarkred.

出挤压辊后，正常的焊管外毛刺形状应为细直线状，顶部圆滑，线上略带间断的突出点，如果外毛刺没有凸起状，焊缝扁平，两侧呈锯齿状，说明温度过高，如果外毛刺顶部不圆滑，毛刺线上没有间断的凸起状，说明焊接温度过低。

Aftertheextrusionroll,thenormalshapeoftheouterburroftheweldedpipeshouldbethinandstraight,withsmoothtopanddiscontinuousprotrudingpointsontheburrline.Iftheouterburrisnotconvex,theweldisflat,andthetwosidesareserrated,itmeansthatthetemperatureistoohigh.Ifthetopoftheouterburrisnotsmooth,andthereisnodiscontinuousprotrudingpointontheburrline,itmeansthattheweldingtemperatureistoolow.

焊接温度也可以通过使用光导纤维新技术的非接触式式温度测量仪进行测量，它不但可以输出准确的，线性化现场模拟信号，而且通过PLC和高频焊机的合理结合，形成能够进行自动调节控制，实时声光报警的闭环控制系统，从而增加焊接温度的控制精度。

Theweldingtemperaturecanalsobemeasuredbyusingthenon-contacttemperaturemeasuringinstrumentwithnewopticalfibertechnology.Itcannotonlyoutputaccurateandlinearizedon-siteanalogsignal,butalsoformaclosed-loopcontrolsystemwithautomaticadjustmentcontrolandreal-timesoundlightalarmthroughthereasonable

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