Developments with seed drill coulters for direct drilling
نویسندگان
چکیده
منابع مشابه
direct drill with active openers for no-tillage systems
no tillage systems can reduce operating costs, enhance soil organic matter, ameliorate soil structure and prevent environmental damage caused by stubble burning. however, the lack of an appropriate direct drill for the hardened soil of arid areas reduces adequate soil-seed contact and, thus, the system has shown contradictory results in past tests. developing a direct drill to place the seed an...
متن کاملA Dynamic Model for a Drill in the Drilling Process
The dynamic model of a drill in drilling process was proposed and investigated in this study. To assure a good drilling quality, the vibration variation on the drill tips during high speed drilling is needed to be investigated. A pre-twisted beam is used to simulate the drill. The moving Winkler-Type elastic foundation is used to characterize the tip boundary variation in drilling. Due to the v...
متن کاملEffect of eccentricity of twist drill and candle stick drill on delamination in drilling composite materials
Drilling is the most frequently employed operation of secondary machining for fiber-reinforced materials owing to the need for structure joining. Delamination is one of the serious concerns during drilling. Practical experience shows that an eccentric twist drill or an eccentric candle stick drill can degrade the quality of the fiber reinforced material. Comprehensive delamination models for th...
متن کاملField evaluation of a grain drill equipped with jointers for direct planting in previous wheat crop residues
ABSTRACT-In conventional agriculture, a large amount of energy is consumed in fuel consumption and depreciation of farm tractors and any other farm equipment mostly in tillage and planting operations. The main purpose of this research was to evaluate a till-planting unit equipped with three jointers. This unit was expected to act as conventional furrow openers such as shovel openers tilling the...
متن کاملComputerized Tomography and C-scan for Measuring Drilling-Induced Delamination in Composite Material Using Twist Drill and Core Drill
Delamination is one of the most concern defects in drilling of composite material. Delamination depends on the factors such as feed rate, tool geometry and wear. The mechanics of drilling composite materials has been examined along with the quality of the hole and the effect of tool design parameters. The capacity of computerized tomography (CT) showing sample cross-section in a nondestructive ...
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ژورنال
عنوان ژورنال: New Zealand Journal of Experimental Agriculture
سال: 1979
ISSN: 0301-5521
DOI: 10.1080/03015521.1979.10427119