无缝弯头是用于管道转弯处的一种管件。在管道系统多使用的全部管件中，所占比例大，约为80%。通常，对不同材料货壁厚的弯头选择不同的成形工艺。目前。制造厂常用的无缝弯头成形工艺有热推、冲压、挤压等

无缝弯头又叫无缝钢管弯头英文名字SEAMLESS ELBOW或者SEAMLESS PIPE ELBOW， 无缝弯头管件因其制造工艺不同，又分为热轧（挤压）无缝弯头管件和冷拔（轧）无缝弯头管件两种。冷拔（轧）管又分为圆形管和异形管两种。

轧制无缝弯头管(guan)(guan)件的(de)(de)原料是(shi)圆管(guan)(guan)坯(pi)(pi)(pi)，圆管(guan)(guan)胚(pei)要(yao)(yao)经过(guo)切割机的(de)(de)切割加(jia)工成长度约为一(yi)米(mi)的(de)(de)坯(pi)(pi)(pi)料，并经传送带(dai)送到熔(rong)炉(lu)内加(jia)热(re)。钢坯(pi)(pi)(pi)被(bei)送入熔(rong)炉(lu)内加(jia)热(re)，温度大(da)约为1200摄氏度。燃料为氢气或(huo)乙炔(gui)。炉(lu)内温度控制是(shi)关键(jian)性的(de)(de)问题(ti).圆管(guan)(guan)坯(pi)(pi)(pi)出(chu)炉(lu)后(hou)要(yao)(yao)经过(guo)压(ya)力穿(chuan)(chuan)(chuan)孔(kong)(kong)(kong)机进行穿(chuan)(chuan)(chuan)空(kong)。一(yi)般较常见的(de)(de)穿(chuan)(chuan)(chuan)孔(kong)(kong)(kong)机是(shi)锥形(xing)辊(gun)穿(chuan)(chuan)(chuan)孔(kong)(kong)(kong)机，这种穿(chuan)(chuan)(chuan)孔(kong)(kong)(kong)机生产效(xiao)率高，产品质(zhi)量好，穿(chuan)(chuan)(chuan)孔(kong)(kong)(kong)扩径(jing)量大(da)，可(ke)穿(chuan)(chuan)(chuan)多种管(guan)(guan)件。穿(chuan)(chuan)(chuan)孔(kong)(kong)(kong)后(hou)，圆管(guan)(guan)坯(pi)(pi)(pi)就先后(hou)被(bei)三辊(gun)斜轧、连(lian)轧或(huo)挤压(ya)。挤压(ya)后(hou)要(yao)(yao)脱(tuo)管(guan)(guan)定(ding)径(jing)。定(ding)径(jing)机通过(guo)锥形(xing)钻(zuan)头高速旋转(zhuan)入钢胚(pei)打(da)孔(kong)(kong)(kong)，形(xing)成管(guan)(guan)件。