冷彎方管、冷彎矩形管是通過外輥與管坯外壁的單向接觸形成彎矩使帶料彎折,冷彎會使彎折線產生壓縮,壓縮效應使彎折線縱向伸長,彎折處金屬出現堆積變厚,這就是冷彎的壓縮/增厚效應。

Cold-formed square pipe and cold-formed rectangular pipe bend the strip through the unidirectional contact between the outer roll and the outer wall of the billet. Cold-formed bend will compress the bending line. The compression effect will make the bending line lengthen longitudinally, and the metal at the bend will accumulate and become thicker. This is the compression/thickening effect of cold-formed. 1)冷彎的優點是反彈小,成型準確,而且只要輥型準確,內角成型的R比較準確。冷彎的優點是可以在無法進行冷彎時進行邊長的彎折,比如方矩管的上邊/側邊同步彎折和精整。冷彎還可以彎折R<0.2t的內角而不致管壁發生斷裂。

1) The advantages of cold bending are small rebound, accurate forming, and as long as the roll shape is accurate, the R of inner corner forming is more accurate. The advantage of cold bending is that it can bend side length when cold bending is not possible, such as synchronous bending and finishing of the upper/side of square tube. Cold bending can also bend the inner angle of R < 0.2T without breaking the pipe wall.

2)冷彎的缺點是有拉伸/減薄效應。冷彎會使彎折處產生拉伸,拉伸效應使彎折線縱向的長度縮短; 第二,冷彎彎折處金屬會因拉伸而變薄。冷彎的缺點是在上邊/側邊同步冷彎時,由于上輥和下輥同時產生壓力,成型力容易超越臨界點,造成邊部失穩內凹,并且也會影響到機組穩定運行和成型質量。

2) The disadvantage of cold bending is the stretching/thinning effect. Cold bending causes tension at the bending point, which shortens the longitudinal length of the bending line. Secondly, the metal at the cold bending point will become thinner due to tension. The disadvantage of cold bending is that when upper/side synchronous cold bending occurs, the forming force is easy to exceed the critical point due to the simultaneous pressure of upper and lower rolls, resulting in the instability of edge concave, and also affecting the stable operation and forming quality of the unit.

這也是方管和矩形管冷彎成型時不同的特點。冷彎方管、矩形管廣泛應用在各大行業，例如：

This is also the different characteristics of square tube and rectangular tube in cold bending forming. Cold-formed square and rectangular tubes are widely used in various industries, such as:

第一、礦用支撐架焊接方管、矩形管,標準號我GB/T14291-2000。代表材質Q235A、B級鋼.主要用于礦山壓風、排水、軸放瓦斯用直縫焊接方管。

First, welding square and rectangular pipes with mine support frame, standard No. I GB/T 14291-2000. The representative material Q235A, B grade steel. Mainly used for mine air pressure, drainage, shaft gas drainage with straight seam welding square pipe.

第二、船舶、碼頭、空港物流作業設備用冷彎方管、矩形管，代表材質Q345A、B、C、D、E級鋼和16Mn錳鋼.主要用于船舶龍門吊、船舶制造、塔吊、塔機、高空作業設備等。

Secondly, cold-formed square and rectangular pipes for ship, wharf and airport logistics equipment, which represent Q345A, B, C, D, E grade steel and 16Mn manganese steel, are mainly used for gantry crane, ship manufacturing, tower crane, tower crane and aerial operation equipment.

第三、鋼結構、幕墻結構用方管、矩形管，代表材質Q235A、B級鋼和Q345A、B級鋼.主要用于大型鋼結構制造、工程結構、建筑施工、橋梁制造、碼頭工程等項目建筑施工。