Leaver fleshy, squamose, spirally arranged, yellowish-white.

叶肉质，鳞片状，状排列，淡黄白色。

The mainstructure parameters of spirally grooved tube are diameter of tube, fin pitch,corrugation depth, wall thickness, spirally angle and spira.

管(亦称纹管)是一个重要分支,它是一种优良高效异形强化传热管件。