Disc harrow is one of the most important soil preparation machines in the tillage and preparation machinery. The purpose of using the disc harrow is to make the ground surface smooth, pine at the top and solid at the bottom, so as to meet the requirements of crop cultivation. The good working condition of the disc harrow is directly related to the quality of the operation, so this article mainly introduces the type, structure, working principle, operation method and maintenance of the disc harrow to provide help for the disc harrow operator.
1.Classification and characteristics of disc harrow
There are many types of disc harrows, and there are different types according to different classification methods:
According to the diameter of disc harrow blades, there are mainly the following three types:
- Heavy-duty disc harrow: the diameter of the disc harrow is 660 mm. This type of disc harrow is mainly used for relatively sticky soil, and the harrow depth can reach 18 cm.
- The second is a light disc harrow: the diameter of the harrow blade is 460 mm, which is used for sandy loam or light soil that is not too sticky, and the harrow depth is about 10 cm;
- The third is the medium-sized disc harrow: the diameter of the harrow blade is 560 mm, It is generally used on ordinary soil, and its harrowing depth is between the heavy disc harrow and the light disc harrow.
According to the way the unit is connected, it can be divided into three types: trailed type, suspension type and semi-suspension type. In general, most of the heavy-duty disc harrows are trailed type, and there are also semi-mounted ones; while most of the light and medium-duty disc harrows are suspension type, of course, there are also trailed types.
According to the arrangement of harrow groups: disc harrows can be divided into single-row harrows and double-row harrows, and double-row harrows can be divided into two types: opposed type and offset type according to the configuration of harrow groups.
HEAVY-DUTY DICS HARROW
2.Structure of the disc harrow
The disc harrow is mainly composed of disc group, disc frame, angle adjuster, suspension device, hydraulic oil pipe, hydraulic cylinder, tail wheel, tail wheel mechanism, etc. Among them, the harrow group consists of disc blades, intermediate pipes, square shafts, bearings and scrapers. The composition of earthenware: the center of the disc is a square hole pierced on the square shaft. When working, the disc and the square shaft rotate together, and the two ends of the square shaft are locked with nuts, and the disc group is worn on the square shaft to form a After a whole, it is connected with the disc frame through bearings, and the middle of the disc blades on the same shaft is separated by an interval tube.
So what are the functions of the main parts of the disc harrow? The function of the soil scraper is to scrape off the soil adhered to the harrow blades, so as to prevent the harrow blades from being stained with too much soil when the harrow is working, so that the harrow can work normally and scrape There is a certain gap between the earthenware and the disc, and this gap can be adjusted according to different soils; the function of the disc frame is to install the disc group and the angle regulator. It is connected to it; the function of the angle adjuster is to adjust the deflection angle of the harrow group, thereby changing the depth of the harrow. There are many kinds of angle adjusters, and the angle adjuster of the disc harrow belongs to the pressing plate type. In addition, there are gear plate type, screw type, hand feeling type, hydraulic type and so on. On specific disc harrows, different regulators are used on different disc harrows, each with its own characteristics. The effect of the hitch or the traction device is then the connection between the disc harrow and the tractor.
3.How the disc harrow works
When the disc harrow is working, the cutting edge plane of the harrow blade is perpendicular to the ground for operation, but the entire harrow group and the forward direction of the machine have an offset angle, that is to say, the harrow group on the same harrow shaft and the forward direction of the machine is at an angle, but the blade plane of the harrow is perpendicular to the ground. The disc harrow advances under the action of traction. It relies on gravity to make the harrow blade cut into the soil and relies on traction to make the harrow blade roll forward. When the disc rolls forward, its motion can be seen as a combination of rolling and moving.
For example, the movement of the disc from point A to point C can be regarded as the combination of the rolling from point A to point B and the lateral movement from point B to point C. During the rolling process, the disc slices are chopped the soil block cuts off the weeds and residual roots, and in the process of lateral movement, the disc blades shovel and push the soil to make the soil rise to a certain height along the disc blades and then fall down to achieve the purpose of crushing the soil. Of course, in the actual process, the two movements are carried out simultaneously.
4.How to adjust disc harrow
The adjustment of disc harrow mainly refers to the adjustment of harrow depth and horizontal direction: the adjustment of harrow depth includes:
- Raise the disc to change the deflection angle of the disc group. In general, the disc depth increases when the deflection angle increases, and on the contrary, the disc depth decreases; the deflection angle of the disc harrow group can be adjusted by changing the hole position in the adjustment device, and each hole position is deviated from the corresponding disc group the angle relationship is shown in the table below.
- Adjust the height of the tail wheel from the ground to limit the raking depth.
| Hole | Front disc gang angel | Rear disc gang angel |
| 1st hole | 14° | 14° |
| 2nd hole | 17° | 17° |
| 3rd hole | 20° | 20° |
| 4th hole | 23° | 23° |
Horizontal adjustments include:
- The horizontal adjustment of the front disc group can be realized by adding shim iron between the disc frame and the crossbeam of the disc group or changing the height of the lower suspension point.
- Longitudinal level adjustment is realized through the height of the left and right lifting arms of the tractor.
5.Disc harrow maintenance and maintenance
- Always check whether the fasteners are loose before and after the operation, and whether the rotating parts are flexible;
- The surface of the components of the hydraulic system should always be kept clean, and the two joint surfaces of the quick self-sealing plug should be wrapped in time after separation, so as not to be contaminated;
- All moving parts should be lubricated frequently;
- After a working season, the entire disc harrow should be disassembled for maintenance once, and the soil on the machine should be removed;
- Disassemble the outer spherical ball bearing, replace the lubricant in the bearing, clean the outer spherical surface of the bearing and the inner surface of the bearing seat, and fill it with lubricant during assembly. After assembly, the sealing ring is not allowed to move relative to the outer ring of the bearing;
- The place where the paint falls off should be filled to prevent rust;
- After the disc blades are cleaned, they should be coated with antirust agent or engine oil;
- Double-acting oil cylinders, hoses and quick self-sealing plugs are all disassembled, washed and maintained, and damaged parts are replaced in time, and stored in a clean and dry place indoors;
- When parking, use wooden boards to pad the disc group, and apply oil to the disc blades to prevent rust. It is best to park indoors.