ERW, SSAW, LSAW的区别

无缝钢管的生产方法大致分为横轧法(Mennesmann法)和挤压法。横轧法(Mennesmann法)是先用横轧辊刺穿管坯，再用轧机将其延伸。这种方法生产速度快，但对管坯的可加工性要求高，主要适用于碳钢和低合金钢管的生产。
挤出方法是用冲孔机将管坯或钢锭打孔，然后用挤出机挤出成钢管。这种方法的效率低于交叉轧制法，适用于高强度合金钢管的生产。
无论是交叉轧制法还是挤压法，都必须先加热管坯或钢锭，生产出来的钢管称为热轧管。热加工生产的钢管有时可以根据需要进行冷加工。冷加工方法有两种:一种是冷拔法，即将钢管通过拉管模具拉拔，使钢管逐渐变细变长;另一种方法是冷轧法，它是Mennesmann兄弟发明的，热轧机是用于冷轧的方法。无缝钢管的冷加工可以提高钢管的尺寸精度和加工光洁度，提高材料的机械性能。

根据制管工艺的不同，传动钢管可分为无缝钢管(SML)。主要用于油田内部集输管道和小直径高压天然气输送管道。长距离油气管道的数量非常少，而且大多是长距离管道。它有三种类型:战争遗留爆炸物，SSAW, LSAW。下表为几种钢管的工艺特点及质量性能比较:

直缝高频焊管(ERW)根据焊接方法的不同分为感应焊和接触焊。乐动app下载安装它以热轧宽带钢卷为原料，经过预弯、连续成形、焊接、热处理、定尺、矫直，并与螺旋焊管、切割等工艺相比具有焊缝短、尺寸精度高、壁厚均匀、表面质量好、以及高抗压性。但缺点是只能生产中小口径薄壁管，焊缝容易出现灰点。、未融合的groove-like腐蚀缺陷。目前应用比较广泛的领域有城市燃气、原油和成品油运输等。

螺旋埋弧焊管(SSAW)是一种带钢盘管，其前进方向与成型管的中心线成角(可调)。成形时焊接，焊缝呈螺旋状。优点是同一规格的带钢可以生产不同直径的钢管有很大的原料范围。焊缝避免了主应力，焊缝应力较好。缺点是几何尺寸很差。焊缝长度焊接缺陷如夹渣和焊接偏差，焊接应力处于拉应力状态。《长距离油气管道设计通用规范》规定，螺旋埋弧焊管只能用于第3类和第4类区域。国外对这一工艺进行了改进，将原材料改为钢板，将成型和焊接分开。经预焊精度，焊后冷胀，焊接质量接近UOE管。目前，中国还没有这样的程序。 It is a spiral pipe in China. The direction of plant improvement. The spiral pipe used in the “West-East Gas Pipeline” is still produced according to the traditional technology, but the pipe end has been expanded in diameter. The United States, Japan, and Germany generally reject SSAW and believe that SSAW should not be used on the main trunk line; Canada and Italy use SSAW in some cases, and Russia uses SSAW in a small amount, and they have formulated very strict supplementary conditions. Due to historical reasons, most domestic trunk lines still use SSAW. .

　　Longitudinal submerged arc welded pipe (LSAW) is produced by using a single medium and thick plate as raw material, pressing (rolling) the steel plate in a mold or forming machine into a tube blank, using double-sided submerged arc welding and expanding the diameter. The finished product has a wide range of specifications, and the weld has good toughness, plasticity, uniformity and compactness. It has the advantages of large pipe diameter, pipe wall thickness, high pressure resistance, low temperature resistance and strong corrosion resistance. When constructing high-strength, high-toughness, and high-quality long-distance oil and gas pipelines, most of the steel pipes required are large-diameter thick-walled LSAW pipes. According to API standards, in large-scale oil and gas pipelines, when passing through Class 1 and Class 2 areas such as alpine areas, seabeds, and densely populated urban areas, LSAW pipes are the only designated applicable pipe type. According to different molding methods, it can be divided into:

　　UOE welded pipe: After the single steel plate is pre-bent at the edge, it is U-shaped, O-shaped, internal welding, external welding, mechanical cold expansion and other processes;

　　JCOE welded pipe: Pre-welding, forming, and cold expanding after welding according to “J-C-O-E”;

　　HME welded pipe: It is formed by the mandrel rolling method according to “C-C-O”, and after welding, it is cold-expanded and other processes