What exactly is SPMT - the strongest means of transport on land - part 1

Chinese name of SPMT: self propelled modular transport vehicle, also known as self-propelled hydraulic flat car. It is mainly used for the transportation of heavy, large, high and special-shaped structures. Its advantages are flexible use, convenient loading and unloading, and the load capacity can reach more than 50000 tons under the condition of multi vehicle mechanical assembly or free combination. It is widely used in equipment manufacturing, petroleum, chemical industry, offshore oil, bridge construction and other engineering fields.

For large-scale engineering construction, the way of off-site prefabricated engineering components and then transported to the site for general assembly is often adopted to effectively shorten the construction period and reduce the construction cost; If the module is disassembled too much, it is conducive to transportation and hoisting, but not conducive to general assembly and commissioning. If the module is disassembled as little as possible, the single module will be very huge, but it will pose a challenge to transportation and hoisting. SPMT came into being under this demand.

Scheuerle type SPMT system composition

1. SPMT module

SPMT modules have 2, 3, 4 and 6 axis specifications, among which 4 and 6 axis modules are the most common. The size design of SPMT is very exquisite. The module is 2.43 m wide, 5.6 m long (4-axis module) and 8.4 m long (6-axis module). It can be transported in standard 20 'and 40' frame containers. Some super large engineering companies have global business scope, but they may not have local branches, so it is necessary to transport the heavy equipment required for the project to the local. The transnational transportation of heavy equipment is generally a combination of ocean transportation and land transportation (highway and railway). The containerization of equipment can bring great convenience and save a lot of transportation costs, so as to realize the rapid dispatching deployment of globalization, This is one of the original design objectives of SPMT.

Each axis is composed of two pendulum axles. Each pendulum axle is equipped with two wheels (air filled tire or solid tire can be selected). The central axis of the two wheels can swing at a certain angle along the center in the vertical plane, which can make the module compensate the height of the ground in the transverse direction.

The module controls the lifting through the hydraulic system. The normal height is 1.5 m, and there is a lifting range of 350 mm up and down. Each tilting axle has an independent hydraulic suspension, but the hydraulic cylinders of several adjacent axles are connected in series into several groups of closed circuits. When passing through the ramp or uneven road, the pressure balance of the circuit cylinder can be used to automatically adjust the height of the hydraulic cylinder of each axle to adapt to the ground and make compensation in the longitudinal direction. Combined with the lateral compensation of the tilting axle, it can effectively adjust the load balance of each wheel, Avoid overloading and bursting of individual tires. The lifting and lowering of the hydraulic system can also be manually controlled to facilitate loading and unloading of goods. When the load is light or no-load, some axles can even be retracted without contacting the ground to reduce the resistance loss.