Semi-trailer beam selection
The beam is the main component that connects the left and right longitudinal beams to form a frame. The torsional behavior of the beam itself and the distribution of the beam on the frame directly affect the internal stress of the frame and the rigidity of the frame. Reasonable design of the beam ensures that the frame has sufficient torsional rigidity.
The cross beam in the semi-trailer frame is stamped or directly used. The former is 15% to 20% lighter than the latter. Generally, the former is widely used.
Common beam structures are:
(1) The circular tube shape has high torsional rigidity, but because the height of the longitudinal beam section is large, in order to transfer the load from the entire section to the beam, many connecting plates must be repaired, which increases the quality and cost of the frame. The process is complicated. In addition, when the torsion is severe, the stress at the connecting plate is large. Therefore, the circular tubular beams are generally arranged only at the two ends of the frame longitudinal beam, close to the lower wing plate, and the overall torsional rigidity of the frame is enhanced.
(2) I-shaped is ideal for load transfer, but the longitudinal beam flange and the beam flange are connected, and the torsion constraint is large, so the internal stress generated by the flange is large.
(3) Groove shape Multi-purpose steel plate stamping molding, simple manufacturing process and low cost, is adopted by many manufacturers, but the torsional rigidity is poor.
(4) Box shape and round tube beam have similar characteristics and have good torsion resistance.
The cross-sectional dimensions of the beam are usually determined by analogy. Considering the serialization, standardization and generalization of products, one or two sizes of beams should be used, and the layout should be different in different ways to meet the requirements of various tonnage level semi-trailers.
When the beams are arranged, the spacing is 700 to 1200 mm, and the specifications may not be followed depending on the actual situation. The middle beam of this semi-trailer is made of sheet-shaped U-shaped beams. 8# hot-rolled ordinary channel steel is used for the through beam, the front side beam and the front middle beam.
Previous: Semi-trailer Support Device
