图1左示出低速、低压气体或液体热传导用的翅片管,但它不适用于高速、高压下的热传导。所以必须改变翅片形状,以满足热传导率和强度的要求。具有一定螺距的,长的平行的纵向螺旋翅片管可满足这种要求。这种翅片管的加工方法是,首先用塑性加工方法(挤压或其它方法)得到平直翅片管(图1中),然后进行相应的调质处理,再在适当温度下进行扭转,以得到所要求 The left side of Figure 1 shows a finned tube for low speed, low pressure gas or liquid heat transfer, but it is not suitable for heat transfer at high speeds and pressures. So the shape of the fin must be changed to meet the requirements of thermal conductivity and strength. Long, parallel longitudinal helical finned tubes of a certain pitch meet this requirement. This finned tube is machined by first flattening the finned tube (in Fig. 1) by a plastic working method (extrusion or other method), followed by a corresponding tempering treatment, followed by twisting at a suitable temperature, To get the request