Rotary drums for RASSOR

grabcad

Rotary drums for RASSOR are built with a simple, reliable, and lightweight construction that can withstand harsh and dusty environments. They consist of a shaft, sides, partition, and spiral coat made from carbon abrasion-resistant steel. One rotational drum features two spiral sections, with an entrance to each section rotated 180 degrees. Both drums are mounted on the shaft at a 90-degree angle between entrances. The optimal spiral construction is between 1.2 and 1.3 turns, depending on its initial radius. Precision in this parameter has a significant effect on the device's efficiency, as any other proportion is not effective. The inner wall of the spiral drum is cut into ribbons that prevent vibration and clogging of input and output channels. The inlet duct features walls on both sides to prevent material from slipping away. The inlet opening of the drum matches the cross-section of the feed channel and is in line, reducing forces exerted on the drum and arm when picking up material. The pitch of the spiral must be optimized based on the fraction of material being processed. Providing all knives with teeth is advantageous, as tooth grooves help the side section sink into the material. Computer simulations are only as good as the input data. Practical tests and theoretical models are insufficient; practical testing is essential to verify results. Practical testing has verified the above statements using a real model. Technical parameters for one drum include a maximum width of scoops engaged at any given time (175 mm), maximum bucket drum mass (5 kg), maximum bucket drum diameter (450 mm), and maximum bucket drum length (360 mm). Achieved parameters for one drum are: bucket drum mass (4.98 kg), bucket drum diameter (450 mm), and bucket drum length (360 mm). The minimum volume captured in the spiral drum shell design is 1.25 turns, with a theoretical volume of 38 liters of material. However, actual results show that when passing through terrain and experiencing partial material loss, the final content of the drum ranges from 24.7 to 25.8 liters of material. Attention should be given to efficiency reduction at lower gravitation and increased efficiency at higher gravitation. Estimated times for drum filling at 20 RPM are 1-3 minutes, depending on inlet size (spiral pitch) and material fractions. Similarly, estimated emptying time at 20 RPM ranges from 0.5 to 2.5 minutes, depending on these factors. Target parameters can be modified by changing relevant parts of the drum or scaling up the design. A smaller radius of the drum results in less energy consumption. Sincerely, Luděk Čechura LC – machinedesign ludekcechura@gmail.com