Summary of common steel knowledge for power tower
Writer： Hengfeng you electric Time：2023-03-22 views：times
*Independent steel structures erected to bear a certain air load, communication or other functions are collectively referred to as iron towers. According to the 2017 industrial output value announced by the State Grid of China, Hengfengyou Electric is 100 billion yuan, and the power tower is included in the 4 trillion yuan of power transmission and distribution equipment.
*The main power towers in the world are generally made of angle steel, steel plate and steel pipe parts, some of which are connected by bolts and some of which are welded. Some 10kV and 35kv main parts attached to the tower are all welded.
*Power tower components are generally hot-dip galvanized for corrosion protection. The requirements for the thickness of the hot-dip galvanized coating in the Chinese national standard "Technical Conditions for Manufacturing of Transmission Line Tower" GB/T2694-2003 are: the thickness should be greater than or equal to 5mm, the minimum average thickness of the hot-dip galvanized coating should be 86 microns, the minimum average adhesion should be 610g/㎡, the minimum average thickness of the hot-dip galvanized coating should be 65 microns, and the minimum average adhesion should be 460g/㎡, The upper limit of hot-dip galvanized coating is not specified in this standard. For enterprises, the closer the thickness of hot-dip galvanized coating is to the lower limit, the better it can save zinc consumption and reduce costs. However, the galvanized thickness of Hengfengyou Power Tower is 25% higher than the national minimum value, ensuring a longer service life of the power tower.
*The weight of electric power tower is as small as 500 or 600 kilograms, and as large as hundreds or thousands of tons (domestic 110kv monomer is generally about 20 tons, and a project is from hundreds to thousands of tons).
*The unit of quantity of electric power tower is "base", and a project is generally tens to hundreds of bases.
*The domestic price is generally 1.8-2 times of the steel price (including 13% tax), and the freight is separately calculated. On July 10, 2022, the steel price is Q235-4300/ton, and the power tower price is about 7700/ton
*Hengfengyou Power Tower has many years of experience in overseas tower projects, and has been successfully sold to more than 50 countries around the world, including Kazakhstan, Uzbekistan, Iraq, Kuwait, the United Arab Emirates, Oman, Qatar, Tanzania, Zimbabwe, South Africa, Uganda, Rwanda, Ethiopia, Ghana, Bangladesh and so on. Product certification is complete. Hengfengyou Electric will provide you with the best power tower product solution .hfy@hengfengyou.com.
2、 Tower material:
Generally, Q235, Q345 and Q420 steel are used for power tower. The letters Q and the numbers 235 and 345 of Q235 and Q345 steel respectively represent the letters and values of yield point.
*Yield point - The phenomenon that the load of the metal specimen does not increase during the tensile process, but the specimen continues to deform is called "yield". The stress at which yield occurs is called yield point or yield strength.
*Our Hengfengyou Electric · Iron Tower subsidiary stipulates that Q235 steel should be marked with red, Q345 steel should be marked with white, and Q420 steel should be marked with green.
3、 The quality grade of steel is divided into five grades of ABCDE, which increase from A to E. It is mainly due to the difference of impact temperature caused by different content of phosphorus and sulfur and other microelements. A - impact test is not required, B-20/C-0/D-20/E-40 (A does not require impact test, BCDE impact test temperature is+20 ° 0 ° - 20 ° 40 ° - 40 °).
*Q235 quality grade is divided into four grades: A, B, C and D. A to D indicates the quality from low to high.
*The quality grade of Q345 steel plate is divided into five grades: A, B, C, D and E
*A - Provide S, P, C, Mn, Si chemical composition and fu, fy δ 5（ δ 10) 1800 cold bending test can be provided according to the Buyer's requirements, but the carbon content and manganese content are not considered as the delivery conditions without the provisions of impact energy.
*B - Provide S, P, C, Mn, Si chemical composition and fu, fy δ 5（ δ 10) , 180 ° cold bending test. It also provides impact energy Ak ≥ 27J at+20 ℃
*C - In addition to the requirements of Class B, the impact energy Ak ≥ 27J at 0 ℃ is also provided.
*D --- In addition to the requirements of Class B, the impact energy Ak ≥ 27J at - 20 ℃ is also provided
*E - In addition to the requirements of Class B, the impact energy Ak ≥ 27J at - 40 ℃ is also provided.
Q345A，Q345B，Q345C，Q345D，Q345E。 This is the classification of grades, which mainly represents that the impact temperature is different, while Q345A grade does not impact; Q345B, impact at 20 ℃; Q345C, 0 degree impact; Q345D, is - 20 ° impact; Q345E, impact of - 40 degrees. At different impact temperatures, the impact value also has different brand and grade requirements as follows: (Q235A belongs to the low alloy series in the plate. Among the low alloy materials, this material is the most common)
4、 Steel tolerance (lower tolerance):
Downward difference of State Grid: 3-4%
Difference under national standard: 4-6% (value 5%)
The actual weight is 3% - 6% lower than the nominal weight
5、 Packaging cost:
Simple packaging 100-200/ton
Reinforced container type packaging 800-1000/ton.
For more common knowledge about power tower, please contact our professional sales personnel WhatsApp:+86158 5325 2696 (Jack)
