As the birthplace of mechanical plate bending machine, Japan began to explore this process as early as the 1950s and 1960s and began to study automatic processing equipment in the 1970s and 1980s. In 1999, Japan developed an automatic processing device, IHI, for curved plate forming,Skilled workers manually operate this kind of processing with many years of practical experience.
The molding effect is checked repeatedly by using the profile template until the quality requirements are met. This kind of processing method relies on expertise with low production efficiency, long processing time, significant-quality fluctuation, and is challenging to control precision. Therefore, shipyards have a strong demand for automation of this process. Many related universities, research institutes, and shipbuilding enterprises at home and abroad have researched the automation of mechanical bending plate processing and achieved phased results.
The Mechanical Plate Bending Machine Device Has The Following Characteristics
Automatically calculate parameters such as the heating path of the curved plate and the heat input rate of the heating head, as well as the error of the shape change of the curved plate after processing.
In the process of processing, the board’s actual and theoretical bending conditions can be compared and evaluated on the PC display screen, and corrections can be made.
Using a CNC machine and laser measuring device can continuously perform bending processing and shape measurement. Its forming speed is much higher than the processing system based on the manual operation or worker experience, significantly reducing processing time. A highly complex hull surface used to take 2~3 days to form by hand, but now it only takes 5~6 hours, which also includes 2 Program computation times of ~3h.
There are 23 hydraulic jacks on the workbench, and the height can be adjusted automatically according to the selected bending shape. The IHI system software automatically calculates the processing plan and then heats it. It is fully automated during heating, except for the manual intervention of the steel plate turning over.
Japan is at the forefront of the world in refined shipbuilding. Japan Steel Pipe Corporation also has trial-produced such equipment. Seoul University in South Korea has developed an automatic mechanical bending plate processing system, which can perform hull shell modeling, shell expansion, heating information calculation, and automated measurement of the shape of the steel plate.
American MIT has developed a fully automatic water-fired bending equipment using laser as a heat source and has made outstanding achievements in researching thin-plate water-fired deformation control. Atlantic&Edison Welding Institute has simple automatic mechanical plate bending machine equipment. Europe, such as Spain, Italy, Denmark, etc., have also trial-produced automated plate bending machines.
China’s first water-fired plate bending machine was jointly developed by Dalian University of Technology, Dalian New Shipbuilding Industry Co., Ltd., Tsinghua University, and Beihang University. The equipment passed the 863 plan intelligent robot acceptance expert group in early 2001. Acceptance, the achievement level, was in a leading position. Its processing parameter prediction system is based on the experimental study of oxyacetylene flame on steel plates, so this equipment still uses traditional oxyacetylene honey to heat steel plates.
The equipment has been tested and processed many hull panels (mainly sail-shaped boards). In 2006, Guangdong University of Technology developed a water-fired plate bending machine using a multi-axis motion control system and a three-dimensional forming processing method. The equipment’s control system consists of a multi-axis motion control part and a PLC control part.
The multi-axis motion control system is an advanced CNC system with an open architecture. Its characteristics are that the industrial computer transmits the motion data and commands to the multi-axis controller, and the multi-axis controller controls the multi-axis motor through the servo driver. The system performs linkage control and position control.
The robot controller is a high-precision profiling measurement system based on laser measurement, which realizes three-dimensional surface measurement and guidance. It solves the problem of errors caused by random deformation of the steel plate during processing.
The robot has 4 degrees of freedom and can be used for automatic processing of complex curved steel plate hydrothermal forming, which improves the production efficiency by more than 2 times. Guangzhou Shipbuilding International and Shanghai Jiaotong University also developed a mechanical plate bending machine at the end of 2005.
In 2007, the Shanghai Ship Technology Research Institute developed the induction heating curved plate forming machine. The above pieces of equipment all adopt the gantry structure.
The advantages of the gantry structure are simple structure, high rigidity, guaranteed positioning accuracy, good stability, and do not require too long mechanical arms. In addition, the control host, servo drives, etc., can also be placed on the operating platform far away from the high-temperature area.
Adopt High-Frequency Induction Heating And Computer Numerical Control
It has the functions of automatic heating, automatic load-balancing support, automatic measurement, automatic line drawing, and manual operation. The supporting device comprises a load cell and electromechanical servo system, which is more practical than the hydraulic servo system involved in the hydraulic jack in Japan.
However, the disadvantage of the mobile gantry structure is that it is relatively bulky, requires a specific working space and a particular working site, and is not suitable for random and flexible working conditions. In 2007, the Dalian University of Technology designed a cantilever hydrothermal processing robot ideal for the automatic processing of large-deflection curved steel plates and a small curved steel hydrothermal processing device suitable for on-site construction.
The software system of the processing parameters of the mechanical plate bending machine In the processing process of the CNC water-fired bending machine, the software system of the processing parameters plays a vital role
Believe In The Future Development Of Mechanical Plate Bending Machines
In modern shipbuilding production, computerized, mechanized, and automated assembly lines have been realized from the early stage of ship design, plate numbering, and blanking to the later stage of hull assembly. The hydrothermal processing of the hull shell is a vital link in the whole shipbuilding process system. Its processing mode has dragged down modern shipbuilding in terms of processing speed and forming quality.
The technological innovation in this process has been Imminent in the modern shipbuilding industry, and it will bring substantial economic benefits. At this stage, mechanical plate bending machines in various countries have achieved some staged results.