Drainage Tile Plow

Overview

A drainage tile plow lays perforated drain pipe deep under a field in one pass, without first digging an open trench. Wet ground drowns crop roots and delays planting, so farmers install a buried network of perforated tile that collects excess water and carries it to an outfall. The old way was to trench, lay pipe by hand, and backfill. A tile plow instead drags a single tall blade through the soil, slicing a narrow slot to depth, and feeds corrugated tile down a chute behind the blade so the pipe is laid at the bottom of the slot as the soil closes back over it. The work that took a crew days is done by one machine, and modern grade control holds the pipe to a precise fall so water always runs downhill to the outlet.

The implement combines the Plow Blade that cuts the slot, the Tile Boot that feeds tile down it, the Grade Control that holds the depth, a heavy Main Frame on tracks, the Pull Hitch to the tractor, a Tile Cart of pipe, and the Hydraulic System that lift and steer.

The plow blade

The Plow Blade does the cutting. A tall, heavy Plow Shank knifes vertically through the soil to drain depth, led by a replaceable Plow Point share that splits the ground at the toe and a Coulter Knife coulter that cuts the surface ahead so the shank slices rather than tears. Two bolt-on Wear Shin strips down the leading edge take the abrasion, and a set of Shear Bolt bolts let the blade break away on a buried rock to save the shank and frame. The draft to pull a blade more than a metre deep is enormous, which is why this is the most heavily built farm implement and needs a large crawler tractor to drag it.

Feeding the tile

Behind the blade sits the Tile Boot, the chute that places the pipe. Its curved Boot Shell carries corrugated tile from the surface down to the bottom of the slot, with Feed Roller rollers that pull the tile off the cart and a Tile Guide that keeps it centred and crush-free, all on Ball Bearing mounts. As the plow moves on, a pair of Closing Wing wings fold the slot walls back over the laid tile so the pipe ends up buried at full depth with soil packed around it. The tile is laid and covered in the same motion, which is what makes the plow a one-pass tool.

Grade control

The value of a drain depends entirely on its fall: a pipe laid even slightly uphill holds water instead of carrying it. The Grade Control holds the pipe to the design grade. A Laser Receiver on a tall Receiver Mast reads a rotating laser plane, or a GPS Grade Module uses RTK GPS to follow a surveyed fall, and a Bare PCB controller with its Microcontroller compares the reading to the target and drives a Proportional Valve that trims blade depth in fine steps through Connector and Wire Bundle wiring. The result is tile laid to within a couple of centimetres of grade over a run hundreds of metres long, which no manual method could hold.

Frame and tracks

The Main Frame has to absorb the colossal pull of the blade without lifting out of the ground. A massive Frame Beam resists the rearward and lifting forces, and the machine rides on two Crawler Track tracks that spread its weight on soft wet ground and grip for the pull, running on Track Roller rollers and Track Idler idlers on Ball Bearing mounts, held together with a Fastener Set. Tracks rather than wheels are used because the ground being drained is by definition soft and wet, and a wheeled machine would bog or skid.

Hitch, tile cart, and hydraulics

A crawler tractor drags the plow through the Pull Hitch, a heavy Drawbar joined by Pull Pin pins and a Clevis, with a Safety Chain backup. The Tile Cart carries the pipe: a large Tile Reel holds a coil of corrugated tile, a Reel Brake keeps it from overrunning and tangling, and the cart rolls on a Cart Frame and two Cart Wheel wheels on Ball Bearing mounts. The Hydraulic System do the lifting and steering: a Power Supply hydraulic pack feeds two Lift Cylinder rams that set blade depth and two Steer Motor track motors, through a Valve Bank and Hose Set sealed by an O-Ring Set.

Use in the field

Tile plows are run by drainage contractors and large farms across flat, naturally wet cropland. A field is surveyed, a drainage plan with mains and laterals is set out, and the plow lays each run to grade in a single trenchless pass, often hundreds of metres long, with the Grade Control holding the fall to the outlet. Trenchless plowing disturbs the surface far less than open trenching and is much faster, so a system that once took a crew a week can be installed in a day. Once the tile is in, wet fields drain after rain, dry out earlier in spring, and yield more, which is why subsurface drainage is one of the biggest one-time improvements a farmer can make to heavy ground.