The process of expansion, specialization and professionalization of stock farming has been going on for decades, nothing new under the sun. Way into the seventies, the animal feed was delivered to the farms with a straight bulk truck with two or three axles. When the farms expanded, the dry bulk haulers also increased in size and weight.
For the time being though, they won’t get any bigger than this immaculate rig, as they’ve reached the Dutch national weight limit of 50 metric tons.
One major advantage of visiting a truck show is that you can take as many pictures as you want without, shall we say, raising suspicion. I caught this splendid Volvo-Welgro combination at the recently held 2019 edition of the WSI XXL show and I came home with so many (detail) pictures, I could probably write its manual.
Anyway, let’s start at the front, with the tractor unit: a 2018 Volvo FH Globetrotter 4×2.
The Volvo is powered by a 12.8 liter, inline-six engine. Its maximum power output is 420 DIN-hp, as it says on both sides.
The diesel fuel has to meet the EN 590 standards. Nothing special or a type of fuel that is hard to get, it has been the norm throughout Europe for many years now.
The cab suspension, rear right side.
Now to the business end, a 2013 Welgro dry bulk tanker with three axles. Welgro (short for the Wellink family from Groenlo, the Netherlands) was founded in the late sixties, the company is fully specialized in building bulk tankers for transporting animal feed.
De Valk (The Falcon) Wekerom is the name of the feed mill.
This falcon tells us that the rig’s payload capacity is around 70,500 lbs (“32 tons of quality!”).
The semi-trailer’s second and third axle are steering axles. They’re not there for bragging rights or to add complexity, the steering axles are a necessity for driving on the generally narrow rural roads, with many tight turns, that lead to the farms and for maneuvering on the farm yards. That is, without damaging the pavement (public roads and farm yards), roadsides, tires and suspension parts.
Here’s where the mechanical steering system starts to work, at the fifth-wheel coupling. A plate with a kingpin, turntable and a wedge is locked into the fifth-wheel coupling; then a sliding bar that goes through the steering wing. There’s another, smaller turntable on top of the wing.
On the left in this picture, the outer end of the steering wing on the semi-trailer’s left side. A long rod on both sides connects the wing to the second axle unit. When the tractor turns, the rods pull on one side and push on the other side.
The rod on the left side ends here.
On the right side of the semi-trailer, another rod connects the second axle unit to the third to make it steer too.
A proven and highly effective system that has been produced for many, many years.
The turntable of the second axle unit.
Ditto, third axle unit.
Loading the tank from above is quite easy, the animal feed goes down through a whole series of hatches (not visible in the picture) with the help of gravity.
The walkway alongside the hatches.
For reasons of safety and convenience, there’s a collapsible railing, pushed up and pulled down by this telescopic cylinder.
The tank is divided in multiple compartments, so that it can be loaded with different types of animal feed.
Now to the unloading process, more technology is needed. This is the PTO-driven air blower installation on the right side of the tractor’s frame.
Then the air flows from the tractor to the semi-trailer.
The tank compartments are kept under pressure from above…
….while the animal feed is literally blown out through this piping system.
Dicht (closed) to the left, Open (which speaks for itself) to the right.
The whole unloading process is operated from the unit in this casing at the back.
The hoses, the connection between the semi-trailer and the silo at the farm, are kept in here.
Another casing for all kinds of equipment and tools needed for the job.
A rear view backup camera, no frivolous luxury, I’d say.
The (un)loading process, old-fashioned style.
Mien leste, it says on the Volvo’s sun visor. That’s local dialect for Mijn laatste. My last one, in plain English. Something is telling me that a very skilled, experienced and professional truck driver is not too far away from his retirement…Till then, keep on trucking!