风管按照风管截面形状的不同，分为三种：矩形风管、圆形风管及椭圆形风管。国内大多使用的是矩形风管及圆形风管。相较于前两种风管，椭圆形风管有漏风率低，结构强度高，刚性好，占用空间高度小等优点，椭圆形风管的使用也逐渐增加。椭圆形风管的制作，是经过椭圆风管机一次性扩张成型至客户所需的椭圆风管的标准尺寸，具有成型好，效率高，操作简便等优点，是通风管道生产中不可缺少的设备。螺旋风管换成椭圆风管前工序之用· 原理是：先将圆风管逐步压成椭圆形，然后进入椭圆风管机，扩张成型。椭圆风管成型能满足大多数风管加工生产的要求，加工长度为3米，椭圆风管除外形美观优点外、强度更高气密性更好且大大降低风管安装空间（高度）扩展了椭圆风管应用范围，代替矩形风管最理想的产品。椭圆风管自投放市场以来，因其本身具有卓越性能及低廉的成本，在通风、空调系统中的应用不断得到推广，大部分产品也广泛应用于造船、通风、净化、纺织、会展、隧道等通风除尘领域。
According to the different cross-section shapes of air ducts, air ducts can be divided into three types: rectangular, circular and elliptical. Most of the domestic air ducts are rectangular and round. Compared with the first two kinds of air ducts, elliptical air ducts have the advantages of low air leakage rate, high structural strength, good rigidity, small space occupation height, etc., and the use of elliptical air ducts has gradually increased. The manufacture of oval air duct is the standard size of oval air duct which is formed by one-time expansion of oval air duct fan to customers' needs. It has the advantages of good forming, high efficiency, easy operation and so on. It is an indispensable equipment in the production of ventilation duct. The principle of the procedure before replacing the spiral air duct with the elliptical air duct is: firstly, press the circular air duct into the elliptical one gradually, then enter the elliptical air duct fan, and expand and form. Elliptical air duct molding can meet the requirements of most air duct processing and production. The processing length is 3 meters. In addition to the advantages of beautiful appearance, elliptical air duct has higher strength and better air tightness, and greatly reduces the installation space (height) of air duct. It expands the application range of elliptical air duct and replaces the most ideal product of rectangular air duct. Since it was put on the market, because of its excellent performance and low cost, elliptical air duct has been widely used in ventilation and air conditioning systems. Most of its products are also widely used in shipbuilding, ventilation, purification, textile, exhibition, tunnel and other ventilation and dust removal fields.