矩形管其实是由于其横截面是方形而命名的，从外形来说方管与圆管最显而易见的区别就是其横断面，方管是方形的圆管是圆形的。其中方管是属于异形管。

In fact, the square tube is named because the cross section is square. From the shape, the most obvious difference between the square tube and the circular tube is its cross section. The square tube is round. The square tube belongs to the special-shaped tube.

这种横断面非圆形的异形管与圆管相比，有较大的惯性矩和截面模数，有较大的抗弯、抗扭能力，从结构来说更加优秀，能够减轻自身重力和节省钢材的优点。所以方管广泛运用于建筑，钢结构工程，钢铁建设等工程建造项目，以及电力工程，除了建筑和电力行业还运用于机械制造，农业和化学机械，起重运输机械。

Compared with the circular tube, the non circular cross-section tube has larger inertia moment and cross section modulus. It has greater bending and torsion resistance, and is better from the structure. It can reduce the advantages of self gravity and save steel. So the square tube is widely used in construction, steel construction, steel construction and other engineering construction projects, as well as electric power engineering. Besides the construction and electric power industry, it is also used for machinery manufacturing, agriculture and chemical machinery, and heavy transportation machinery.

矩形管的分类方式多样化，所以我们方管的细类有很多，更何况不同方管厂家的产品又会有很大的差异，如果方管按照我们方管的表面处理种类可以分为热镀锌方管、电镀锌方管、涂油方管以及酸洗方管等等。

The classification of the square tube is diversified, so there are a lot of fine categories of our square tubes. Moreover, there will be a lot of difference in the products of different square tube manufacturers. If the square tube can be divided into hot-dip galvanized square tube, galvanized galvanized square tube, oil coating square tube and acid washing square tube, the surface treatment types of our square tube can be divided.

在玻璃幕墙材料中使用比较广泛的是热镀锌方管。

Hot-dip galvanized square tubes are widely used in glass curtain wall materials.

矩形管如果按生产工艺来划分，则可分为热轧无缝方管、冷拔无缝方管、挤压无缝方管以及焊接方管等等。无缝方管顾名思义就是没有焊缝的钢管，无缝方管的应用挺广的。大部分方管是由无缝圆管加工而成的，而相较于圆管，方管具有大抗拉强度，质量轻的优点。

If the square pipe is divided according to the production process, it can be divided into hot-rolled seamless square tubes, cold drawn seamless square tubes, extruded seamless square tubes and welded square pipes. Seamless square tube, as the name suggests, is seamless steel pipe, seamless square tube is widely used. Most of the square tubes are made of seamless tubes. Compared with round pipes, the square tube has the advantages of large tensile strength and light weight.