Study of the Cutting Mechanism of Oil Tree Peony Stem

Abstract

Tree peony is a deciduous shrub endemic to China, and peony seed oil (PSO) is an important plant oil resource. However, at present, pruning and fruits harvesting of oil tree peony are mainly completed by manual work, which has seriously affected production efficiency. By the need to develop efficient pruning and harvesting equipment for oil tree peony, this study investigated the effect of cutting tool geometric parameters and cutting speed on cutting force and energy. A cutting device was set up, and six cutting tools with different blade angle and sliding-cutting angle were prepared for this research. Stems in different growth stages (anthesis and fructescence) were collected for cutting experiments. In this paper, four blade angles (25°, 30°, 35°, and 40°), three sliding-cutting angles (0°, 10°, and 20°), and four cutting speeds (25 mm/min, 50 mm/min, 100 mm/min, and 200 mm/min) were considered in the experiments. The results showed that cutting force and energy are positively related to blade angle, and the minimum cutting force and energy are required in cutting with 25° blade angle. Compared to straight cutting (sliding-cutting angle is 0°), sliding cutting can obviously reduce the cutting force and energy. Furthermore, the best sliding-cutting angles of cutting tools have discrepancies dependent on the stems in different growth stages. In fructescence, 10° sliding cutting required the lowest cutting force and energy. In contrast, the best sliding-cutting angle of stems in anthesis was 20°. On the other hand, the cutting force and energy were obviously proportional to the cutting speed, which increased by the cutting speed increasing. Therefore, under the condition of ensuring the cutting efficiency, reducing the cutting speed can effectively reduce the power consumption. These results are an important basis for pruning and harvesting machine development for oil tree peony.

Determination of the Mechanical Properties of Parsley Stems Related to the Design of Processing Machines

“…BOYDAŞ et al [16] reported that shearing force values of sainfoin stems obtained at an oblique angle of 28 • were lower than those at an oblique angle of 0 • . Similar results were reported by Yore et al [17] for rice straw, by Allameh and Alizadeh, [18] for rice stems, by Ghahraei et al [19] for kenaf stems and by Liu et al [20] for peony stems. The proper design of the cutting equipment can maintain the quality of the harvested product while minimizing the force and energy needed to accomplish the task.…”

Identification of differentially expressed miRNAs and their target genes in response to brassinolide treatment on flowering of tree peony (Paeonia ostii)

“…Tree peony is a perennial woody deciduous shrub, belonging to the family Paeoniaceae , section Moutan, and genus Paeonia , 1 and it has been renowned for its large flowers, diverse flower color, graceful appearance, and strong fragrance. 2 , 3 Tree peony has a long history of ornamental cultivation, and with long-term natural and artificial selection, there are more than 2000 varieties that vary in flowering traits of tree peony worldwide.…”

Analysis and Experiment of Cutting Mechanical Parameters for Caragana korshinskii (C.k.) Branches

“…Since the tool is subjected to a positive pressure perpendicular to the edge and a lateral force parallel to the edge when cutting the branch, the relative slip between the branch and the edge increases when the slip cutting angle increases, thus enhancing the cutting action of the edge on the branch and reducing the peak cutting force (Figure 13). In contrast, during unsupported cutting, the trend of reduction of peak cutting force is relatively flat due to the relatively small trend of variation of chipping angle with tool wedge angle [37].…”

“…From the slip-cutting theory [20,36], it is known that when the slip cutting angle is greater than 20 • , branches will produce the phenomenon of external slip, so the slip cutting angle is set to 5 • , 10 • , 15 • and 20 • in the single-factor experiment of tool slip cutting angle for a total of four levels; when the other groups of single-factor tests are conducted, the slip-cutting angle is taken as 20 • to ensure that the minimum cutting force is obtained. Comprehensive consideration of the wedge edge strength and blade life will be the relationship between the tool wedge angle singlefactor experiment wedge angle set to 20 • , 25 • , 30 • , 35 • -a total of four levels [37,38]; when conducting the other single-factor test, the wedge angle was 25 • . Referring to previous studies [3,19], the cutting gap was set from 0.1 to 3 mm and set to four levels in the singlefactor test of cutting gap; when conducting other group tests, the cutting gap is taken as 1 mm.…”