The agricultural plough operates in one of the most unpredictable environments imaginable: beneath the soil surface. Hidden rocks, tree roots, or buried debris pose a constant threat to the structural integrity of the implement and the tractor. To mitigate this risk, modern Hydraulic Reversible Ploughs rely on ingenious, purpose-built safety systems—primarily shear bolts and hydraulic relief mechanisms.
These features are not merely add-ons; they are critical design elements that save farmers massive amounts of money and downtime by protecting the core machinery.
1. The Shear Bolt: The Sacrificial Guardian
The shear bolt is the simplest and most common form of protection against catastrophic impact damage.
How it Works: The shear bolt is a specially engineered bolt that connects the plough's working element (the leg or tine holding the share and mouldboard) to the main plough beam. This bolt is deliberately the weakest link in the assembly.
The Action: When the plough body hits an immovable object with excessive force, the shear bolt is designed to snap (shear) instantly. This releases the plough body, allowing it to swing back and out of the way of the obstruction, preventing the shock load from being transferred to the main frame, the headstock, or the tractor's linkage.
The Benefit: Replacing a simple, inexpensive shear bolt in the field takes minutes. Repairing a twisted frame or a broken headstock, on the other hand, can cost thousands and halt operations for days.
2. Hydraulic Relief: The Reset Button
Some high-end reversible ploughs, particularly those designed for very tough or rocky ground, use hydraulic reset systems instead of, or in addition to, shear bolts.
How it Works: Each plough body is held in its working position by a hydraulic cylinder pre-charged with nitrogen gas or connected to a pressurized system. When the plough body encounters an obstruction, the pressure exerted overcomes the force of the gas/oil in the cylinder.
The Action: The cylinder compresses, allowing the plough body to move up and backward over the obstacle. Once the obstacle is passed, the internal pressure immediately forces the body back down into its correct working position without the tractor stopping.
The Benefit: This system provides non-stop plowing in stony fields, significantly increasing APH (Acres Per Hour) and eliminating the labor required to stop, replace the shear bolt, and restart.
3. Protecting the Core System: Hydraulic Overload
Beyond protecting against physical impact, the hydraulic system on a reversible plough, such as the one found on the adjustable Tejas Plough, is also protected against internal pressure failure.
The Reversal System: The hydraulic cylinder that flips the plough 180 degrees must be protected. If a hose becomes blocked or the reversal movement is physically obstructed, pressure in the lines can spike dramatically.
Relief Valves: Quality ploughs incorporate hydraulic relief valves into the headstock or cylinder assembly. These valves are calibrated to open and release the fluid back to the reservoir if pressure exceeds a safe threshold. This prevents a burst hose, a damaged cylinder seal, or a broken coupling.
By incorporating both mechanical fail-safes (shear bolts) and hydraulic safety valves, manufacturers ensure their ploughs can operate reliably in unpredictable conditions, giving farmers confidence that their capital investment is protected. The focus on safety allows implements like the versatile Tejas Plough to deliver exceptional durability and low maintenance costs.
