ChMZAP-9990 Russian 57-Ton Semi-Trailer

The CHMZAP-9990 semitrailer is an excellent, rugged tank transporter and general bulk cargo carrier design capable of operations on paved roads, natural roads, trails and selected off-road terrain. The CHMZAP-9990 has three equally spaced axles and 12 tires (wheels). The 12 tires are arranged in pairs on half-axles, with each pair independent of the pair across the vehicle from it. There is no axle across the vehicle. Each half-axle and wheel pair is mounted on a center pivot which allows 15 degrees of roll freedom in each direction. All three axle pairs on each side of the vehicle are connected to a walking beam or rocker arm type. This beam is 8 feet long, tapered towards the ends and a massive weldment in structure. The extreme wheel pairs (axles 1 and 3) are connected at the ends of the beam, while the middle axle is co-located with the walking beam pivot in the center of the beam and connected through an auxiliary walking beam of somewhat unknown design. Loads are transferred from the semitrailer through the walking beam pivot to the walking beam. The first and third axles receive their loads at the ends of the walking beam while load to the center axle is through the auxiliary walking beam. The CHMZAP-9990 semitrailer has stakebody sides and a cargo floor bed. When carrying general cargo it provides tremendous capability. The gooseneck section includes two spare tires, landing legs, and a tire-handling boom. A very useful feature of this semitrailer is the low-tire-inflation-pressure warning system. The system is designed to warn the operator of a fall in tire pressure below 4.4 kg/cm2 in any of the 12 tires on the trailer (5.5 kg/cm2 is normal). Sensors in each wheel of the trailer make an electrical connection when tire pressure falls below the designated pressure. This activates a horn or buzzer in the operator's cab, warning only that one or more tires is low. The operator must then stop the truck and go to a terminal panel box on the trailer. This panel box contains a series of press-to-test buttons, arranged in a pattern to represent wheel placement. By pressing each button or a series of them, the operator can determine the low tire; the buzzer will stop sounding when the button (or buttons) for the low-pressure wheel (or wheels) is pressed. Components on the trailer are connected by means of a detachable shielded conduit to the buzzer and a 24-v electrical power source in the tractor.