Combine Harvester Operation: Core Industry Knowledge to Reduce Grain Loss Rate
The debugging of core components of combine harvesters, such as the header, threshing and cleaning system, and conveying system, is the foundation for reducing grain loss. Different grain varieties (wheat, rice, corn), different maturity levels and field conditions have significant differences in the requirements for component parameters, which need to be adjusted in a targeted manner to avoid problems such as missed harvesting, incomplete threshing, and grain breakage caused by parameter deviations.
The header is the first process of grain harvesting. Improper adjustment of the header can easily cause header losses (missed harvesting, grain drop), accounting for 30% to 40% of the total loss. The following parameters need to be focused on:
The threshing and cleaning system is the core link of grain harvesting, which directly affects threshing loss, breakage loss and cleaning loss. It needs to be adjusted in accordance with the principle of "improving threshing rate and cleaning efficiency on the premise of ensuring the breakage rate does not exceed the standard".
The conveying system (conveying trough, auger, elevator) is responsible for conveying the grain harvested by the header to the threshing system, and then conveying the cleaned grains to the grain tank. Its smooth operation directly affects intermediate losses. It is necessary to check whether the conveying trough scraper and auger blade are intact to avoid grain leakage caused by worn components and excessive gaps; adjust the conveying speed to match the header feeding speed to prevent grain accumulation and blockage, and reduce grain scattering loss caused by blockage.
The operating level of combine harvester drivers has a significant impact on the grain loss rate. According to industry research, the operation loss rate of skilled drivers and novice drivers can differ by 2% to 3%. It is necessary to strictly follow the following operation specifications to reduce human errors.
The operating speed needs to match the field conditions, grain yield and machine feeding capacity, avoiding blind pursuit of speed that leads to increased losses. Generally, the operating speed for wheat and rice harvesting is controlled at 3-5 km/h, and for corn harvesting at 2-4 km/h; when the grain yield is too high, humidity is too high or stubble height is too low, the operating speed needs to be reduced to ensure the machine works under rated load and reduce entrainment loss and blockage failures. Before operation, a low-speed test harvest should be carried out first, and the speed should be gradually adjusted to the normal speed according to the test harvest situation. It is strictly forbidden to use the walking gear for harvesting directly.
When turning at the field head, stop the operation and turn by reversing to avoid the header continuing to harvest during turning, which may lead to grain missed harvesting or rolling. When operating to the field head, slow down in advance and turn after the header completely leaves the crop to reduce grain scattering at the field head. For irregular plots, the "circular" operation method can be adopted to avoid frequent turning, improve operation continuity and reduce missed harvesting.
Faced with special working conditions such as lodging, high humidity and excessive weeds, the operation method needs to be adjusted to reduce losses. When harvesting lodged crops, operate in the reverse direction of the lodging direction and adjust in conjunction with the reel to enhance the reel lifting effect; for grains with high humidity, appropriately reduce the operating speed and increase the cleaning air volume to avoid incomplete cleaning caused by grain caking; for plots with excessive weeds, clean the field weeds in advance or adjust the header height to reduce the amount of weeds brought in and prevent the cleaning system from being blocked.
Different grain varieties, planting modes and field environments have different requirements for combine harvester models. Choosing a suitable model is the premise of reducing losses. At the same time, adjusting the operation plan according to the operating environment can further reduce the loss rate.
The performance stability of combine harvesters directly affects the operation quality. Regular maintenance can avoid increased losses caused by component failures and extend the service life of the machine. Maintenance work should be done well before, during and after operation.
Conduct a comprehensive inspection of all components of the machine, including the header, threshing drum, cleaning device, conveying system, etc., and replace severely worn scrapers, blades, reel teeth and other components; check the engine, gearbox, hydraulic system, etc., to ensure normal operation; clean up residual straw, grains and other debris in the machine to prevent blockage; debug the core component parameters in advance according to the grain variety to be harvested and make preparations for test harvest.
During operation, stop and inspect every 2-3 hours, clean up straw and debris in the header, conveying trough, cleaning sieve and other parts to prevent blockage; check whether all components are firmly connected to avoid grain leakage caused by loose components; monitor parameters such as engine speed and hydraulic system pressure to ensure the machine operates under rated conditions and avoid failures caused by overloading.
After the operation is completed, thoroughly clean up residual grains, straw and debris in the machine to prevent mold and corrosion of components; check the wear of all components and repair or replace damaged components in time; carry out lubrication and maintenance on key parts such as the engine and gearbox; park the machine in a dry and ventilated place, take rainproof and dustproof measures, and make preparations for the next operation.
With the improvement of agricultural mechanization and intelligentization levels, the intelligent upgrading of combine harvesters has become an important direction to reduce the grain loss rate. At present, mainstream domestic agricultural machinery enterprises have launched combine harvesters equipped with intelligent control systems, which can monitor parameters such as feeding volume, grain breakage rate and loss rate in real time through sensors, and automatically adjust the drum speed, fan air volume, operating speed, etc., to achieve precise loss reduction. Some models are also equipped with Beidou navigation systems, which can realize linear operation and automatic docking, reducing missed harvesting and field head losses. In the future, with the application of artificial intelligence and the Internet of Things technology, combine harvesters will achieve more precise working condition perception and parameter adjustment, further reducing the grain loss rate and promoting the grain loss reduction work in the grain harvesting stage to a new height.
To sum up, reducing the grain loss rate of combine harvester operation needs to take into account the four core links of machine debugging, operation specifications, model adaptation and maintenance, and at the same time rely on intelligent technology upgrading to continuously improve the operation quality. Agricultural machinery practitioners need to master relevant technical points proficiently, standardize the operation process, implement every detail in place, effectively hold the "last line of defense" in grain production, and contribute to ensuring national food security.