Influence of rice straw forming factors on ring die wear and improved wear prediction model during briquetting

Abstract

Briquetting is an effective way to ensure the comprehensive utilisation of straw. However, in the production of straw briquettes there can be problems of low productivity and high-power consumption caused by ring die wear. The working principle of briquetting machines and wear of the ring die wear studied to determine the relationship between different forming factors of straw briquette and ring die wear. The wear mechanism of the ring die was analysed by scanning electron microscope, and the pattern of wear on the inner wall of the ring die in the extrusion direction was studied. The friction and wear test of rice straw briquette was used to analyse the influence of different moulding factors on the friction coefficient. Results showed that the wear depth of the ring die module decreased slowly in the direction of extrusion. Deep scoring was found in the entrance section. Wear in the tail section was weak and mainly appeared in the form of spalling pits. The main wear mechanisms of the ring die were abrasion and fatigue. The main forming factors affecting friction coefficient were briquette density, moisture content and extrusion velocity. According to the comparison between the wear prediction model and the actual production, the maximum deviation between the calculated value and the simulated value was 12%, and the minimum deviation was 5%. The wear of circular ring die module was low, which could improve service life. • Wear mechanism of the ring die module is mainly the abrasive wear of micro-cutting. • Wear depth and total wear depth value of each step is calculated by ANSYS software. • Wear value data by wear prediction model is verified by actual briquetting production.