Disc Harrow consists of various parts:
The dished smooth disk with square holes in the center are generally used. These Discs have self sharpening features but the edges may sometimes become blunt due to rough usage on stony field locations. The blunt edges give poor penetration and cutting. In such situation, it is necessary to ground the edges with portable electric grinder.
Most Disc Harrows have perfect round disc shape. in some cases, there is heavy residue left on the field and heavy trash cutting is required. The notched discs are an answer to such a requirement. These Disks are available in the range of 16″-24″ diameter. Most of the modern ploughs use diameter range of 1″-24″.
§ Disc Gang
Disc Gang is formed with 3-13 discs assembled together on a square shaft called Gang Shaft or Gang Bolt. The spacing between the discs falls between 6″-9″ with cast iron spools.
Each gang of discs needs a square frame
§ Disc Bearing
§ Disc Bumper
These are placed on the harrow disks to scrap out any soil material which has hot stacked.
§ Weight Boxes
In some Disc Harrows, a box is bolted in which weights are placed for the purpose of greater penetration into the soil.
There are some settings or points that should be kept in mind while using harrows.
A) Leveling: To get maximum performance from the equipments, ensure that they are in level position whether you look from top, right or left. Try these methods:
i) Leveling Left and Right: This setting is accomplished by tractor’s lower link leveling crank.
ii) Leveling Fore: You should check implement before lowering and the setting should be level fore and after. This arrangement is done by tractor top link.
To ensure uniform depth, the above stated setting should be maintained.
B) i) Side Draft: The offset disc harrow will trail nicely behind the tractor provided the side thrust of front gang is same as that of the rear part. The relative cutting angle should be carefully examined.
ii) Severe Side Draft:
In this case, the cutting depth of rear disc gang should be increased or lowered by using tractor top link. For ex: When Tractor pulls to right, rear gang should be lowered.
When tractor pulls to the left, the rear gang should be raised.
These observations will help you in troubleshooting:
If implements choke between the discs, then you can assume these things:
i) The sped of tractor is very slow.
ii) Gangs are angled.
iii) Scrapers are not set right.
iv) Soil is too wet.
v) Gangs are not rolling nicely.