The effect of knife wear and sharpening mode on chipper productivity and delays

Mihelič, Matevž (avtor), Vusić, Dinko (avtor), Ursić, Branko (avtor), Zadro, Antonio (avtor), Spinelli, Raffaele (avtor)

The production of wood chips can be achieved using different types of wood chippers whose productivity can be influenced by many factors including proper knife management. Research was conducted to determine the productivity of the new Diamant chipper in chipping air-dried tops stacked at a roadside landing and to compare the efficiency of dry sharpening and wet sharpening in restoring chipper productivity, the time required by dry sharpening with that of knife replacement, and the cost of dry sharpening to knife change in real-life conditions. To clearly define the influence of knife management, a model of the effect of knife wear on chipper productivity was produced. Analysis of variance was used to check the significance of any differences in chipping and total time consumption per cycle. Multiple regression was used to express the relationship between chipping time consumption per cycle and the cumulated mass processed by a set of knives—the latter taken as an indicator of knife wear. The study lasted 10 full workdays, included a total of 136 truckloads or 3560 t of fresh wood chips (or green tons = gt), and resulted in the average productivity of 59.0 gt per productive chipping hour (excluding all delays) or 39.4 gt per machine scheduled hour (including all delays). Delays represented 37% of total worksite time. Knife management (dry sharpening or change) accounted for 30% of the total delay time due to raw material contamination. Dry sharpening took 30% less time than a full knife change. As wear accumulated and knives lost their edge, the chipping time per cycle increased from 25 in the first cycle (full truck load) to 38 min in the third cycle. The presented study offers robust productivity figures, together with a reliable estimate of the productivity losses caused by knife wear, and could help improve knife management in order to increase chipper productivity as well as reduce unnecessary delays.

• Jezik: Angleški jezik
• Ključne besede: dry sharpening, wet sharpening, delay time
• Vrsta gradiva: Članek v reviji
• Tipologija: 1.01 - Izvirni znanstveni članek
• Organizacija: BF - Biotehniška fakulteta
• Status publikacije: Objavljeno
• Različica publikacije: Objavljena publikacija
• Datum objave: 26.06.2024
• Leto izida: 2024
• Št. strani: Str. 1-11
• Številčenje: Vol. 15, iss. 7 [article no. 1101]
• PID: 20.500.12556/RUL-159275
• UDK: 630*36
• ISSN pri članku: 1999-4907
• DOI: 10.3390/f15071101
• COBISS.SI-ID: 200781827
• Datum objave v RUL: 05.07.2024

Gradivo je del revije

• Naslov: Forests
• Skrajšan naslov: Forests
• Založnik: MDPI
• ISSN: 1999-4907
• COBISS.SI-ID: 3872166

Licence

• Licenca: CC BY 4.0, Creative Commons Priznanje avtorstva 4.0 Mednarodna
• Povezava: http://creativecommons.org/licenses/by/4.0/deed.sl
• Opis: To je standardna licenca Creative Commons, ki daje uporabnikom največ možnosti za nadaljnjo uporabo dela, pri čemer morajo navesti avtorja.

Sekundarni jezik

• Jezik: Slovenski jezik
• Ključne besede: suho brušenje, mokro brušenje, čas zamude