直縫焊管多絲埋弧焊焊接工藝

由於直縫焊管多絲埋弧焊具有過冷度大以及焊速快的特點，基本上將平衡狀態擺脫了，如果採用與母材相同的化學成分作為焊接材料，焊縫金屬會出現低塑性、低韌性、高強度的力學效能。

Because of the characteristics of super cooling and fast welding speed， the equilibrium state is basically removed。 If the same chemical composition as the base metal is used as the welding material， the weld metal will have low plasticity， low toughness and high strength mechanical properties。

在針對具有較高技術要求的油氣輸送直縫焊管進行操作時，如果要充分確保管道的安全執行，需要具有良好的衝擊韌性和塑性焊縫，為了避免焊接接頭的抗裂性、塑性和韌性因焊縫金屬的高強度而降低，在焊接高強度、低碳和低合金直縫焊管時，需要控制焊縫中合金元素和碳元素的質量分數，因此，在選擇焊接材料時，需要考慮焊縫金屬在各個方向上的抗裂性、塑性和韌性。

In order to fully ensure the safe operation of oil and gas pipeline， it is necessary to have good impact toughness and plastic weld。 In order to avoid the reduction of crack resistance， plasticity and toughness of welded joint due to the high strength of weld metal， it is necessary to control the welding seam in the welding of high strength， low carbon and low alloy straight welded pipe Therefore， the crack resistance， plasticity and toughness of weld metal in all directions should be considered when selecting welding materials。

同時，在針對大口徑直縫鋼管等中厚板結構剛性較大的進行焊接的時候，要想預防由於較大的接頭約束度而導致裂紋的產生，在允許的設計範圍之內，選擇強度略低於母材的焊接材料，即採用低匹配的接頭形式，採用這種方法，可以預防由於焊材強度的降低而導致的焊縫實際強度下降，從而大大增加焊縫的韌性，降低接頭的裂紋傾向，增加接頭焊縫的綜合力學效能。

At the same time， in order to prevent cracks caused by large joint restraint， the welding material with strength slightly lower than the base metal should be selected within the allowable design range， that is， the low matching joint form should be adopted。 This method can prevent cracks caused by the decrease of welding material strength As a result， the toughness of the weld is greatly increased， the crack tendency of the joint is reduced， and the comprehensive mechanical properties of the joint are increased。

不同直徑的焊絲在埋弧焊當中具有各不相同的電流適應範圍，焊絲熔化量在這個範圍內會隨著電流的增加而增加，影響焊縫成形效果，而電弧自身調節作用則會因為達不到該範圍的電流而受到影響，導致電弧不穩定，因此，在直縫焊管的多絲埋弧焊中，焊絲的直徑需要根據焊接電流來選擇。

Different diameters of welding wire have different current adaptation range in submerged arc welding。 The melting amount of welding wire will increase with the increase of current in this range， which will affect the weld forming effect。 However， the arc self-regulation effect will be affected because of the current not reaching this range， which will lead to the arc instability。 Therefore， in the multi wire submerged arc welding of straight welded pipe， the diameter of welding wire will increase It needs to be selected according to the welding current。

如果能夠確保在統一焊絲直徑範圍內的多絲埋弧焊焊絲的焊接電流，就可以用相同直徑的焊絲進行焊接，如果不能確保，焊接時不能選擇不同的焊絲組合，直縫焊管多絲埋弧焊的焊接質量也受多種因素的影響，如焊絲幹伸長、焊絲傾角、焊絲間距和焊絲排列等，焊絲的排列有三種形式，即直列式、橫列式以及縱列式，如果從焊縫成形的角度對三種排列方式進行比較，可以發現直列式焊縫熔合比較小，橫列式焊縫寬度較大，縱列式焊縫較深且較窄。

If the welding current of multi wire submerged arc welding wire within the range of uniform wire diameter can be ensured， the same diameter wire can be used for welding。 If it cannot be ensured， different wire combinations cannot be selected during welding。 The welding quality of multi wire submerged arc welding of straight welded pipe is also affected by many factors， such as wire dry elongation， wire inclination， wire spacing and wire arrangement， etc There are three types of wire arrangement， i。e。 in-line， horizontal and vertical。 If the three types of wire arrangement are compared from the perspective of weld forming， it can be found that the fusion of in-line weld is smaller， the width of horizontal weld is larger， and the width of vertical weld is deeper and narrower。

在直縫焊管多絲埋弧焊過程中，需要注意以下問題，一般採用直流-交流的混合配置作為多絲埋弧焊的電源，而採用反接作為直流，需要採用穩弧性好、黏度適中、熔點高以及顆粒細的高鹼型焊劑運用在直縫焊管多絲埋弧焊中，透過以上研究，希望能夠有利於多絲埋弧焊焊接工藝在不同材質以及不同口徑等方面的進一步發展。

In the process of longitudinal welded pipe multi wire submerged arc welding， we need to pay attention to the following problems。 Generally， DC-AC hybrid configuration is used as the power source of multi wire submerged arc welding， while reverse connection is used as DC。 High alkali type flux with good arc stability， moderate viscosity， high melting point and fine particles is needed to be used in longitudinal welded pipe multi wire submerged arc welding。 Through the above research， we hope it can be conducive to multi wire submerged arc welding Further development of arc welding technology in different materials and different diameters。

部分文字來源於網路，如有侵權請聯絡刪除！