1.前言双层卷焊管(一般称邦迪管)早在1922年就已被美国底特律汽车厂用做汽车燃料管、美国的邦迪公司于1935年第一次得到邦迪管制造专利权。所谓双层卷焊管(如图1所示)是将双面镀有钎料的带钢(如图2)在特制的双层卷焊管机组上成型为双层卷焊管管坯,然后 1. Introduction Double-rolled tube (generally known as Bondi tube) as early as 1922 has been used as the United States Detroit auto factory car fuel pipe, the United States Bondi company in 1935 for the first time by the Bondi patent manufacturing. The so-called double-roll pipe (shown in Figure 1) is double-sided solder plated strip (Figure 2) in a special double-roll pipe unit forming double-rolled tube blank, and then