Pics: Tri-axle wagon is a ‘weapon of grass destruction’

Austrian grass and tillage equipment manufacturer Pottinger is currently undertaking a nationwide demo tour of Ireland with its Jumbo Combiline 7210 forage wagon.

AgriLand caught up with the substantial machine as it tackled some “Irish” grass in the west – just outside Dunmore.

Gazing at the machine, which was being run behind a ‘new-shape’ Tier 4B New Holland T7.230, you get a sense of its sheer scale – considering how the 230hp tractor is practically dwarfed by it.

Pottinger Jumbo

It’s not surprising that the 7210 has a DIN (true) capacity of an impressive 40.1m³. In the real world of Irish grass, this probably equates to a capacity for about 1.5ac (18t) of average-yielding grass silage. That was the message from Pottinger’s Demonstrator and Territory Manager, Ben Stokes.

Pottinger Jumbo

Up front, at the business end, there’s a 2.3m-wide pick-up. It made short work of the relatively heavy swath of grass during our visit.

Pottinger Jumbo

The pick-up is controlled from both ends by steel cam tracks, which work in conjunction with sealed, twin-race roller bearings. The pick-up tines move through a sweeping arc which, claims Pottinger, provides for “optimum protection of the sward, lower levels of soil contamination and unnecessary wear of the tines”.

A swath roller is also fitted to promote good crop flow even when operating at high loading speeds.

Keeping the pick-up running “smoothly” over undulating terrain are two hydraulically-folded jockey wheels. These are located outside the tractor’s tracks. This, says the company, “provides optimum ground tracking”.

Further helping the pick-up on this model is an optional support roller – located behind the middle of the pick-up. Because it’s located centrally, it can’t sink into the tractor’s wheel marks.

The grass travels from there into the ‘Powermatic Plus’ rotor, which has eight rows of tines arranged in a spiral and a diameter of 31.49in (800mm). The rotor is mounted on self-aligning ball bearings at both ends and has a shaft diameter is 3.93in (100mm).

The crop is then forced through a maximum of 45 knives, which are spaced at what Pottinger describes as an “optimum 34mm interval” to achieve the “best possible feed value for ruminant animals”. The knives themselves are produced from hardened tool steel and incorporate a serrated edge. They also have an “extra thick rear edge for an extended service life”.

Pottinger Jumbo

The 7210 can be specified with Pottinger’s optional Autocut knife-sharpening system, which enables sharpening directly on the loader wagon itself (without removing individual blades). This process is controlled by buttons located at the side of the wagon or, alternatively, can be triggered from the in-cab terminal, and is fully automatic.

“We advise customers to adopt the method of little and often with the Autocut system – to get the most from their knives as well as to reduce fuel consumption,” commented Stokes.

Once chopped, the grass is fed into the “box” body; it is constructed from steel profile panels. No extension bars or roof ropes are deemed to be needed, due to the fact that the side walls extend beyond the forage compression flap.

Pottinger Jumbo

To maximise the 7210’s capacity, it uses a combination of sensors mounted on the front flap and upper panel section, as well as on the rear door. There’s also a torque sensor on the front pivot point, which links the chassis and hydraulic drawbar.

These sensors all communicate with each other to form an automatic loading system.

Unloading is taken care of courtesy of the scraper floor system, which consists of six scraper floor chains and two gearboxes on the 7210. This system can unload the entire 40.1m³ capacity at floor speeds of up to 24m/min. The unloading process is automatic; it is engaged by pressing a button on the in-cab terminal.

Pottinger Jumbo

One of the most noticeable features on the 7210 is, without doubt, its tridem axle configuration; its steering function is controlled via two link arms connected to the Dromone spoon hitch.

Pottinger Jumbo

Pottinger Jumbo

This ‘forced’ or ‘active’ steering system works in both forward and reverse. Fitted to each axle are optional oversize 710/50R26.5 Nokian tyres. Completing the package, the entire machine sits on a hydro-pneumatically sprung chassis.

Pottinger Jumbo