Non-Alloy Cold Rolled Q235 Q345 Rectangular Pipe Pre Galvanized Welded Square Hollow Section

Forming method
1, solid bent

Solid bending, as the name implies, is compacted bending, and the inner and outer rollers and the inner and outer walls of the tube blank are compacted in both directions during solid bending.

1) The advantages of solid bending are small rebound, accurate forming, and as long as the roller type is accurate, the R of inner Angle forming is more accurate.

2) The disadvantage of solid bending is the stretching/thinning effect.

First, the real bending will produce tension at the bending, and the stretching effect will shorten the longitudinal length of the bending line;

Second, the metal will be thinned by stretching at the bend.

2, empty

Empty bending is through the one-way contact between the outer roller and the outer wall of the tube blank to form a bending moment to bend the material. Empty bending will cause compression of the bending line. The compression effect makes the bending line lengthwise and the metal at the bending place appears to accumulate and thicken, which is the compression/thickening effect of empty bending.

1) The advantage of empty bending is that side length bending can be carried out when real bending is not possible, such as the top/side synchronous bending and finishing of square rectangular tube. You can also bend in the air. 0.2t inner Angle without wall rupture.

2) The disadvantage of air bending is that in the upper/side synchronous air bending, due to the pressure of the upper roll and the lower roll at the same time, the forming force is easy to exceed the critical point, resulting in the edge instability concave, and will also affect the stable operation of the unit and forming quality. This is the square tube and circular tube empty bending molding different characteristics.

Square tube uses
The purpose of the square tube construction, machinery manufacturing, steel construction projects, shipbuilding, solar power stents, steel structure engineering, electric power engineering, power plants, agricultural and chemical machinery, glass curtain wall, automobile chassis, airport, boiler building, highway railings, housing construction, pressure vessel, oil tank, bridge, power station equipment, Lifting and transportation machinery and other high load welding structures.