SUBSOILER

SUBSOILER

- an implement for intermittent tillage at depths sufficient to shatter compacted subsurface layers, equipped with widely spaced shanks either in-line or staggered on a V-shaped frame

- are large and robust chisels, which can reach down to a working depth of more than a meter. Because of the tractive force required, their use is restricted to tractors, not animals.

SUBSOILER

- sometimes called mole plow- breaks up the soil so that water may

seep into the open spaces and be stored

- works best when the soil is hard and dry

*If the soil is wet, only a compacted path, which is of little value, is made through the earth.

Draft

Because subsoilers work deep, the draft is great – so heavy that usually only one unit is pulled at a time even by large crawler tractors.

Some of the smaller units, working about 16 in. deep can be pulled by a two-plow tractor. Larger ones working as deep as 3 ft, require a crawler tractor with as much as 80 hp.

Basic Parts

Shank or Standard – used for attaching a tillage tool to a beam. It is vertical or curved toward the front.

Ripper Point – tool attached to the shank of the subsoiler to cut through the soil

Transverse Tool Bar – part of the main frame to which shank assemblies are attached

Gauge Wheel – auxiliary component that helps maintain uniform operating depth and for adjusting depth of cut

Wear Shin – metal plate attached to the shank to reduce abrasion and enhance durability of the shank

Foot – found at the lower end of the shank where the point is bolted

Attachments

wheels and axles. Usually one wheel powers the axle so that it can act as a crank to raise the soil-working unit. The wheels vary in size – some may be as high as 38 in and have rims as wide as 8 in. The wheels lift the subsoiler, keep it level, and act as depth guides. The axles, of high carbon steel, are 2 – 3 in. in diameter.

Colter - to assist in cutting grasses rather than having it accumulate on the shank.

Attachments

Mole – an oval-shaped object with diameter 3-8 in. pulled behind the unit leaving a tunnel.

Colter - to assist in cutting grasses rather than having it accumulate on the shank.

Fertilizer attachments – for fertilizer application

Classification

According to type of mounting- Drawn type subsoiler – main

frame is mounted far behind the tractor. Guide wheels are necessary for transport

- Three-point hitch mounted – main frame is mounted to the rear of the tractor using the 3-point hitch linkages

Classification

According to type of shankStraight shankCurved or parabolic shank

Principle of Operation

The subsoiler shall be attached on the tractor. After being transported to the field, the implement shall be lowered on the soil. The desired operating depth shall be set by adjusting the gauge wheels or through the action of hydraulic cylinders. The subsoiler shall be pulled by the tractor to cut through the soil.

Safety and Maintenance

The subsoiler shall be painted and shall have a rust-free finish.

The subsoiler shall be free from manufacturing defects that maybe unsafe.

All bolts shall conform to standards for strength application and shall be made of hot-galvanized steel for corrosion resistance.

Grease points for shank protection mechanism shall be provided.

Tools for adjustment of shank assembly shall be provided.

Determination of draft

A spring, hydraulic or stain-gauge type dynamometer shall be attached to the front of the tractor on which the implement is mounted. Another auxiliary tractor shall pull the implement-mounted tractor through the dynamometer in neutral gear but with the implement in its operating position. The draft in the measured distance of 20 m as well as the time it takes to traverse it shall be recorded. On the same field, the draft in the same distance shall be recorded while the implement is lifted above the ground. The difference in the draft readings shall yield the draft of the implement.

References

PAEShttp://en.wikipedia.org/wiki/Subsoilerhttp://

www.tradenote.net/keyword/Subsoiler/