Technological Characteristics of Rectangular Steel Tubes

Like other steel tube materials, the production of rectangular steel tubes is also based on national standards or industry standards. Therefore, the width, height and wall thickness are generally some common specifications. The rectangular square tube refers to the hollow metal profile with rectangular and square cross-section, which is used in construction, machinery manufacturing, shipbuilding, hardware, steel structure engineering and other industries. According to the common specifications of rectangular steel tubes in the market, the theoretical weight table of rectangular steel tubes and the technological characteristics of rectangular steel tubes are made by enthusiast. Here we'll introduce it to you next.

Theoretical Weight Table of Rectangular Steel Tubes:

Type	Theoretical weight of model (kg/M)	Type	Theoretical weight of model (kg/M)
50*30*2.5	3.02	25*25*1.2	0.94
50*30*3	3.6	40*40*2	2.29
50*32*2	2.2	40*40*2.5	3.02
50*35*2.5	3.32	40*40*4	4.68
55*38*2	2.8	50*50*2.5	3.81
60*40*2.5	3.81	50*50*3	4.44
60*40*3	4.44	50*50*4	5.74
60*40*4	5.74	60*60*2.5	4.52
70*50*4	7.02	60*60*3	5.38
80*60*3	7.09	60*60*4	7.02
80*60*4	8.22	70*70*4	8.22
80*60*5	10.25	70*70*5	10.2
90*40*2.5	5.19	80*80*4	9.96
90*60*5	10.47	90*60*5	13.85
100*60*3	7.3	100*100*4	11.65
100*60*4	9.16	100*100*8	23
100*60*5	11.53	120*120*4	14.16
100*60*4.5	14.41	160*160*4.5	19.2
160*80*4.5	15.84	220*80*6	27.1

Theoretical weight calculation of rectangular steel tubes:
According to the principle of weight = density x volume, the calculation formula of rectangular steel tube is as follows:
Theoretical weight (kg / M) = (width + height) * 2 * wall thickness * 0.00785. (Tips: width, height and wall thickness are in hectare.)
For example, the weight per meter of 100 * 80 * 4 rectangular square tube is (100 + 80) * 2 * 4 * 0.00785 = 11.304kg.

Process requirements of rectangular steel tubes:
① The rectangular straight pipe must be made on the special imported pipeline to ensure the accuracy of the air duct production and the airtightness of the air duct.
② The blanking of rectangular air duct fittings should be completed automatically by using computer software on the imported special machine, and the automatic plasma cutting process should be completed by the imported special plasma cutting machine for sheet metal.
③ The imported automatic occluder should be adopted in the connection place of rectangular air ducts.
④ The rivetless connection technology should be adopted in the connection between the rectangular air duct body and the plug-in flange, and the imported equipment should be used for the rivetless connection.
⑤ The connection process of connecting plate flanges and plug-in flanges should be adopted in the connecting flange of the rectangular air duct. When the length of large side of air duct is less than or equal to 2000mm, the connection form of common plate flanges should be adopted. When the length of large side of the air duct is greater than 2000mm and less than 2500mm, the connection form of plug-in flanges should be adopted. The reinforcing rib of rectangular air duct shall be mechanically pressed, and the spacing between reinforcing ribs is about 300 mm.

Technological characteristics of rectangular steel tubes
Advanced technology: The international first-class numerical control equipment for the pipe making was used. And the computer software programming was also used. Then, we only need to input the relevant data of the air duct shape. After a few seconds, it can automatically generate the parts' shape, composition quantity and data connection of various accessories, then they will be sent to the plasma cutting machine for automatic blanking.

The air duct with software programming and automatic blanking has the following advantages:
1. The form of air duct is diversified. The specification is complete, which brings convenience to the design and selection, and meets the needs of different HVAC engineering systems.
2. Good interchangeability: The sizes are accurate. The pipe fittings are standard and they are easy to replace.
3. The appearance and inner wall are flat and smooth. From the perspective of the air duct performance, the inner wall is smooth and streamlined, which makes the air resistance small.