BOWAS Extrusion Process
The production of strands of various diameters and perforations for different types of single base propellants.
The capacity depends on the consistency of the dough, the configurations and diameters of the propellant strands and on the number and models of inserted dies. So for single base propellants Extrusion presses from 750 up to 4300 kN main cylinder force are available.
BOWAS is in a position to offer a modern, state of the art plant concept which fits into the concept of existing client’s plant sections actually under modernization and as stand alone solutions. The plant concept aims at offering the most economic solution which follows the client’s requirements.
The kneading dough is manually fed into the mass container by the operator. As soon as the mass container is filled, the operator starts the pre-pressing by means of a two-hand actuated switch – important for safety reasons. For the lifting and automatic positioning of the dough-barrels special devices are available.
Once the pre-pressing is finished after numbers of cycles, the mass container is manually revolved for 180° around one pillar. Now, the main pressing takes place automatically, with the selected speed. The pressure increases during start of pressing. So strands will be produced passing dies with different formats, then the single strands will be directed and collected by special devices, available as accessory kits.
For the highest performance of the press it is required to fill the second mass container and actuate the pre-presser in the same time as the main pressing is carried on.
After finishing the main pressing, the mass containers are manually revolved back to their start position. By means of an ejector cylinder, the die support is removed throughout the mass container, the die unit is replaced for cleaning and ready for reusing. Afterwards, the cycle can start again.
Advantages of the process
Compared to other existing pressdehydration processes BOWAS offers the following advantages:
Safety – Special care has been dedicated to increase the safety of the dehydration process. All equipment has been designed and built in accordance with the latest and most advanced technology and is based on our extensive experience in the field of explosives and propellant production. An important increase in safety is achieved by remote controlled pressing stages. CCTV cameras are used for monitoring critical and hazardous operations where operating personnel is not allowed to be present during operation.
The process is designed with the necessary automation level in order to minimize the number of operating personnel in areas of potential risk. This also reduces the frequency and duration of the operators’ activities in these areas. The dehydration press is equipped with interlock- ing of doors and controls to safe- guard the remote operation and a double independent process control instrumentation may be installed additionally as an option. A metal detection of the NC cake, as well as ventilation arrangements are important for the safety. The floor has to be kept always water-wet. Going along with safety equipment BOWAS provides a detailed risk analysis, focusing the special demands of safety of the dehydration process, such as adiabatic compression of air and solvent vapour, presence of dry NC, overfilling of the press cylinder etc.
Ergonomics for the operating personnel in the different operation steps are improved by mechanized handling providing safety and cost effective production with known and tested technology.
Better economic results –
The design and concept of BOWAS’ pressing process together with a predefined degree of automation offer an optimum balance between investment costs and necessary personnel requirements. The equipment is designed for a high availability at low maintenance costs.