Truck crash performance

Because the expansion tube has a stable energy absorption effect, it has been used in collision waveform generators in China. For example, the Safety and Energy Saving Collision Laboratory of Tsinghua University uses it to obtain the deceleration curve required in the European regulation ECE R80. Shanghai Guanchi The automobile safety company applied the expanded deformation tube to the waveform generator of the trolley test, and Yang Hui and others from the Shanghai Motor Vehicle Inspection Center used it as an energy-absorbing component of the front end of a light vehicle. In fact, the expansion tube can not only be used as a waveform generator and an energy-absorbing component of the front end of a light vehicle, but can also be directly applied to the rear protection device of a truck to absorb collision energy and reduce vehicle body deceleration.
3.1 Structural design of expansion tube rear protective device
Since the punch and the expansion tube are not 100% axially stressed, in order to prevent the punch and the expansion tube from relative bending deformation during the collision energy absorption process, a casing is added outside the expansion tube. The rear protective device cross beam and the rear protective column are relatively fixed. The punch is placed in the opening of the expansion tube. The uprights of the rear protection device and the longitudinal beams of the truck, between the casing and the longitudinal beams, and between the punch and the columns are all connected by rotating hinges to ensure rear protection. Free rotation of the device.
When the vehicle hits the rear protective device, it first hits the cross beam of the protective device, and then the cross beam pushes the punch connected to it to expand the expansion tube. During the expansion process, the expansion tube absorbs a large amount of collision energy and it yields. The strengths are 400 MPa, 235 MPa, and 386 MPa respectively, and the thicknesses are 10mm, 4 mm, and 7 mm respectively. Among them, the expansion tube consists of primary and secondary expansion tubes. The primary expansion tube is a part with a diameter of 60 mm, and the secondary expansion tube is a part with a diameter of 52 mm.
3.2 Regulatory verification of expansion tube rear protection device
The protective device is subject to regulatory verification according to the dynamic test requirements of the GB11567.2-2001 standard. The number of model nodes is 67195, the number of units is 61096, and the total mass of the rear protective device is 96.38 kg. The maximum penetration of the mobile barrier is 156 mm, which is less than the 400 mm stipulated in the regulations; the rebound speed of the mobile barrier after collision is 1.1 m/s, which is less than the 2m/s stipulated in the regulations; the deceleration of the mobile barrier is the maximum The value is 27.3 g, which is less than the 40 g required by regulations, so the rear protection device meets the national standard requirements. In addition, it can be seen that the deceleration of the moving barrier during the collision is small and the pulse width is large, indicating that the expansion tube rear protection device has a better energy absorption effect.