Optimal Design and Testing of a Crawler-Type Flax Combine Harvester

Abstract

China is a large flax-growing country, with planting area and production ranking among the top three in the world. However, the cultivation range of flax in China is very broad, complex, and diverse, resulting in different planting scales and patterns, making it difficult to apply foreign large combine harvesters, and China lacks a dedicated flax combine harvester. This research improved the design of the 4LZ-4.0 crawler-type flax combine harvester for the regional features and flax cropping patterns in China. First, the structure, technical parameters, and working principles of the machine were introduced; second, the theoretical analysis and optimization of key components were performed; and finally, with the advancing speed of the machine, the speed of the threshing drum, and the speed of the suction fan as independent variables and the rate of removal and the total loss rate as response values, a three-factor, three-level response surface analysis method was used. For each component and response value, a mathematical model was created, and the factors and their interactions were evaluated and confirmed. The results demonstrated that the three parameters impact the threshing drum speed, advancing speed, and centrifugal fan speed in that order of priority, as well as the total loss rate in that order of priority. The machine’s optimal operating settings were 1.5 m·s−1 advancing speed, 788.49 r·min−1 threshing drum speed, and 885.34 r·min−1 centrifugal fan speed, and the validation test results indicated that under the typical dryland dense flax cultivation mode, it had a 97.46% threshing rate and 2.99% total loss rate after the test. This demonstrated that optimizing operational parameters may decrease losses in the process of mechanical flax harvesting, enhance harvesting efficiency, and satisfy the marketable flax harvesting standards.

Study on the Shear and Bending Mechanical Properties of Millet Stem

“…Additionally, comparing the bending strength with the shear strength, it was found that the bending strength of millet stems was significantly greater than the shear strength. This was consistent with the conclusion drawn by Shi et al [35] from mechanical tests on sesame stems. Therefore, when harvesting millet stems, a cutting-type harvester should be selected, and the cutting height should be set at the fifth internode.…”

Finite element analysis and optimization design of large vibrating screen based on equivalent static load method

“…Integrating them into high-capacity grain combine harvesters enables efficient harvesting and screening directly in the field. Notable models include Xing Guang 4LZ-5.0Z [1], Crawler-Type Tiger-Nut [2], and 4LZ-4.0 Crawler-type Flax Combine Harvesters [3]. Vibrating screens can also autonomously screen harvested crops, as seen with the 4YK1860 vibrating screen [4].…”

Current Flaxseed Dehulling Technology in China

“…Gansu Province is one of the main areas producing of flax in China, where the sowing area ranks first among the seven major flax-producing areas [4]. Its average annual sowing area is about 9.7 × 10 8 hm 2 and average annual total output is about 1.51 × 10 5 t, accounting for 30.5% of the national sowing area and for 38.67% of the country's total output, respectively; the province's sowing area and production rank first in the country [5][6][7].…”