Wickert: Interest in composite presses for producing ballistic plates is on the rise
Since 2021, Wickert Maschinenbau has recorded a considerable increase in interest in composite presses for producing ballistic panels. They are used for armoring to protect civilian and military vehicles, ships, and aircraft from gunfire.
In particular, there is a demand for complete systems comprising a composite press, automated loading and unloading, along with efficient temperature control. Most recently at the end of 2021, Wickert commissioned a complete system for a supplier to the Australian Ministry of Defense.
It delivered a WKP 52000 composite press that had been modified to meet the requirements of ballistic plate production. Weighing 150 t, the press features a lower-piston frame design with a fully hydraulic closing system and boasts a press force of 52,000 kN and 1,600 x 2,500 mm heating plates.
Ballistic plates made from up to 60 layers of fiber composite
Producing ballistic panels involves processing blanks of up to 60 layers of fibers impregnated with a special plastic. These are made of high-performance materials such as aramide and high-performance polyethylene. Combined with glass, ceramic, and metal fibers made of aluminum oxide, silicon carbide, boron carbide, aluminum, and armor steel, they are then heated in composite presses and pressed into fiber-reinforced composite panels.
Homogeneous tempering
Composite presses used to produce ballistic panels must adhere to specific requirements. To begin with, the blanks and semi-finished products are heated and cooled very uniformly in the press, while the temperature deviation over the whole panel remains at a mere ±3 ºC.
In a first step, the tempering system heats them to 40 ºC and then, in a second step, to 160 ºC. This melts the plastic; the press gives the blank the desired shape. Then it cools down again in the mold to 40 ºC and, once removed, to room temperature.
Uniform pressure
Moreover, press cylinders made of high-strength steel – six on the WKP 52000 – ensure a high force density and homogeneous pressure across the entire surface. A fine pressure setting of just 960 kN was provided as an optional feature for the project in Australia. Typically, the minimum press force is ten percent of the maximum output; on the WKP 52000, this would otherwise have been 5,200 kN.
High plane parallelism
Finally, the presses stand out thanks to their extremely precise closing motion. The system’s high plane parallelism with a maximum tolerance of 0.025 mm/m contributes to this.
To ensure quality and monitor production, sensors also capture all the system’s process data. The information is stored for accurate documentation of the production process.
Composite presses are produced at the company’s headquarters in Landau, Germany
All of Wickert’s hydraulic composite presses are developed and manufactured to meet customized requirements at the company’s headquarters in Landau, Germany. In addition, processing temperatures of up to 500 °C are possible, as well as freely selectable pressing forces of up to 100,000 kN. The dimensions of the presses and their precision heating plates can be freely selected. The requirements of the Industry 4.0 age require automation and networking just as much as the integration of additional production processes, such as RIM and RTM injection.