工字型钢不论是普通型还是轻型的，由于截面尺寸均相对较高、较窄，故对截面两个主袖的惯性矩相差较大，因此，一般仅能直接用于在其腹板平面内受弯的构件或将其组成格构式受力构件。

I-steel whether ordinary or light, because the section size are relatively high and narrow, so the moment of inertia of the main sections of the two sleeve is large, therefore, generally only can be directly used in the web plane bending member or the of lattice stress components.

槽钢分普通槽钢和轻型槽钢。热轧普通槽钢的规格为5-40#。经供需双方协议供应的热轧变通槽钢规格为6.5-30#。槽钢主要用于建筑结构、车辆制造、其它工业结构和固定盘柜等，槽钢还常常和工字钢配合使用。

Channel steel is divided into ordinary channel steel and light channel steel. The specification of hot rolled ordinary channel steel is 5-40#. The specification of hot rolled and variable channel steel supplied by both suppliers and suppliers is 6.5-30#. Channel steel is mainly used in building structure, vehicle manufacturing, other industrial structure and fixed disk cabinet, and channel steel is often used in conjunction with I-steel.

按专业用途分，有油桶用板、搪瓷用板、弹板用板等；按表面涂镀层分，有镀锌薄板、镀锡薄板、镀铅薄板、塑料复合钢板等。

According to professional use, there are oil  board, enamel plate, bulletproof plate and so on. According to surface coating, there are galvanized sheet, tin plate, leaded sheet, plastic  steel plate and so on.