Walther Trowal
A new dosing technology allows Walther Trowal to lower the usage of consumables and energy to produce firearms ammunitions by up to 25%. The company has developed a revolutionary three-stage process for finishing the surface of ammunition cartridge casings during the multi-step metal forming process. It reduces the cycle times for degreasing, washing, rinsing, pickling and passivation (corrosion protection).
The new process is an essential part of the overall “ammunitions finishing” system and precisely controls the addition of consumables like acid, washing or passivation additives and process water during each of the metal forming stages. The new ammunitions finishing system from Walther Trowal is being used for the first time in a production line of a globally leading ammunitions supplier. Preliminary tests had proven that the new system will lower the usage of consumables and water by up to 25%.
The surface characteristics of the cartridge casings during the metal forming process from the circular blank to their final shape play an essential role in the manufacturing operation. After each single forming step during this highly interlinked process, different surface finishing methods must be applied. For all surface finishing stages Walther Trowal is using a specialized machine, namely a rotary vibrator, model CM.
Walther Trowal develops and produces the chemical compounds used for the various process stages, in-house. The same is true for the respective process water cleaning systems. This ensures that all equipment components and consumable materials are perfectly adapted to each other.
“Walther Trowal is one of the few companies who can offer total surface finishing solutions, from the circular blank, all the way to the finished casings: The equipment, all consumable materials and process water cleaning systems are made in-house and interact flawlessly with each other,” says Christoph Cruse, general sales manager at Walther Trowal. “This guarantees highly efficient processes and excellent quality of the finished ammunitions. With the experience of more than 100 finishing systems delivered to the ammunitions industry our experts know every detail of the ammunitions manufacturing process. Therefore, they can perfectly integrate the surface finishing function into the metal forming operations of our customers.”
At one of the largest manufacturers for military ammunitions more than 40 rotary vibrators from Walther Trowal are in operation for handling various finishing tasks for cartridge casings during their different production stages.
Background: Technical details
The first step in the production of ammunitions consists of circular blanks, which are stamped out of brass sheet metal coils. The blanks are then deep-drawn into cups, which are subsequently deep-drawn into ammunition casings. After each metal forming step the surface of these intermediate products must be specially treated to ensure the functionality of the completed ammunition. The different treatment stages include pickling, washing, drying and passivation. The CM rotary vibrators from Walther Trowal have proven to be the ideal machines for handling the various process stages. They generate intensive contact between the blanks, cups and casings on the one hand and the different chemical compounds on the other hand. This ensures that all contaminants are removed from the surface of the work pieces.
After each metal forming step the surface of the casings must be treated with special methods. For example, they must be washed, de-greased, pickled, dried or passivated. All these operations take place in CM rotary vibrators from Walther Trowal, which are strategically placed in the ammunitions production line. The rotary vibrators for the various production stages are technically absolutely identical. The only variation is that they’re using different chemical compounds. This equipment uniformity greatly facilitates maintenance and repairs.
A huge benefit of the use of rotary vibrators to produce cartridge casings is that the continuous vibration carries the compound not only to the outside but also to the inside of the casings. This helps to lower the overall compound consumption significantly and reduces the cycle times. CM vibrators from Walther Trowal are also used during the production of bullets made from led, specifically for deburring and edge-radiusing of the raw work pieces.