1. Before use, the feeding guide rail shall be debugged in strict accordance with the debugging requirements of the equipment, and the feeding guide rail shall be fixed after being adjusted to the specified position size. If the actual position of the feed guide rail is smaller than the specified position size, the undercut will not be formed; if it is larger than the specified position size, because the feed is too wide, the undercut size will be out of tolerance, resulting in two sheets unable to be spliced or waste of materials; if the feed guide rail is seriously skewed, it is easy to produce uneven deviation defects before and after the undercut width.
2. The thickness of the undercut plate should be within the specified range of products of various specifications. If it is less than the minimum thickness, the undercut is prone to crack, wrinkle and other defects; if it is greater than the maximum thickness, the square of the plate thickness is in direct proportion, the abnormal damage of the forming roller, overload of the transmission system and blocking of the car will be caused by the obvious increase of the bending force.
3. The processing capacity of the seaming machine of the square duct making machine is designed according to the processing of ordinary steel plate. The commonly used ordinary steel plate, galvanized steel plate and plastic composite steel plate all have good seaming forming performance. The strength of stainless steel plate is higher than that of ordinary steel plate. Before using stainless steel plate to bite, the forming experiment should be done first, so as not to overload the equipment and cause excessive wear or mechanical accidents. Due to the poor plasticity of the aluminum plate, it is easy to crack during the undercut forming. Before the construction, the forming test should also be carried out. At the same time, due to the lack of elasticity of the aluminum plate, the aluminum plate air duct cannot be undercut by snap type.
4. The minimum length of the undercut section of the sheet shall not be less than 300 mm, otherwise, the horizontal resistance of undercut will be greater than the friction force of the sheet fed forward due to too little contact between the sheet and the forming roller, making the sheet slip between the forming rollers and accelerating the wear of the forming part of the roller.