Although it is convenient to install the aluminum truss, it has certain construction requirements, especially under the conditions such as winter:
If the construction site of the truss is available, the drying oven shall be set, and the drying temperature is 300 degrees centigrade, and the time is 4 to 5 hours. It is also possible that the truss structure should comply with the performance requirement of negative temperature coating, and it is strictly prohibited to use water-based coating.
Welding rods and wires used in welding trusses below zero need to choose low hydrogen welding electrode with low yield strength and good impact toughness. After the drying is qualified, it should be stored in the oven. The temperature should be set between 80 and 100 degrees centigrade. When used, the temperature should be taken out in the heat preservation tube (for safety).
The high strength bolts and ordinary bolts used in the erection of truss shall have the product qualification certificate, and the high strength bolts shall carry out the reinspection of the torque coefficient and axial force, which can be used after meeting the requirements. When installing truss at minus temperature, need to notice that because of temperature change caused by the change of the truss structure shape and size, if the truss is made at room temperature, if the temperature is negative degrees Celsius under the premise of installation, must take into account the negative temperature shrinkage of metal materials. Below zero degrees Celsius, if the electrode is exposed for more than 2 hours to be rebaked, it should be noted that in order to ensure the quality of the project, the baking number of the electrode should not exceed 3 times. At room temperature, the basic electrode used must be roasted according to the product factory certificate before use, and the welding rod shall be raised to a higher level.