Stig Wahlström has developed the hydraulic valve for UniCarriers' new reach truck series Tergo. The specially designed valve block forms the heart of the system and handles all hydraulic movements of the truck. "Everyone smiles when they get to drive the truck," says Bengt Andreasson, UniCarriers.
"Because it is so flexible and works so well. Even with empty forks. When operating a control, the truck reacts exactly the way you want and you keep direct contact with the forks. This means better control and precision because objects stay right where they should stay. It also allows truck operators to work more efficiently with greater precision and speed."
Without boasting, we think this is the best reach truck on the market," says Bengt Andreasson, who works at UniCarriers' construction department for hydraulics.
He is referring to the latest addition to the Tergo range, that went into series production just over two years ago. "According to us, it's the battleship among reach trucks," he continues. A truly optimized pallet mover. It lifts with a speed of 0.8 m/sec and can handle loads up to 2.5 tonnes. It is used mainly for distribution purposes in the retail sector. These trucks keep on going in three shifts around the clock, week after week, year after year. They are real workhorses".
Rapid and proportional lowering of forks at low pressure drops
Bengt, who works in product care, which basically means achieving cost reductions and technology improvements, continues: "The challenge was to achieve a rapid and proportional lowering of the forks at low pressure drops. Much oil needs to be drawn away when the forks are lowered. A forklift is typically a little jerky, so creating a very smooth and stable movement is crucially important. We analysed the whole valve market and our choice fell on Stig Wahlström. And after outperforming the competition they have indeed provided us with both high quality and delivery performance."
The driver can use three features simultaneously
One of the advantages of the new series is a 6 percent lower battery consumption in the hydraulic system. The valves are constructed as a modular system, according to the number of features you need. Reach, tilt and side shift, up to a lifting height of 13 meters, and more. The driver must also be able to use three functions simultaneously. "It's been a long development journey with multiple technologies from both companies working very well together," continues Bengt Andreasson.
"Our demands are very high, ranging from a low noise level to great controllability and speed. At times Stefan spent weeks at our premises and modified the valves to accommodate our requirements. In effect, we had an extra engineer in Stefan. Moreover, it was a very gratifying cooperation," says Bengt. "We will continue cooperation with several models that are under development."
Stefan Sääf is a Key Account Manager at Stig Wahlström and as such he is also working with UniCarriers. As a technical sales representative he's also involved in product development, using CAD. He has been working together with UniCarriers for many years and has been engaged in the entire valve system.
Driving the truck puts a smile upon your face
"Everyone smiles when they get to drive the truck," says Bengt. "Because it is so flexible and works so well."
"The dynamics of our cooperation has been important. We developed exactly what UniCarriers needed. Since we have our own block production, we can customise everything to their requirements. The products also have to fit physically. We have designed the products and utilized every available millimetre of space," Stefan concludes.
The main valve is a valve block that forms the heart of the system and handles all hydraulic movements of the truck. It controls every movement, such as lifting and lowering, reaching, tilting, side shifting, clamping functions and other optional features.
UniCarriers is one of the world's leading manufacturers of trucks
UniCarriers in Mölnlycke, Sweden, is part of a worldwide group. From the humble beginnings in 1958, in the Gothenburg bedroom apartment of founder Knut Jacobsson, the company has expanded steadily and is now the seventh largest manufacturer of forklifts in the world. The company has however always been true to it's roots and all development and manufacturing still takes place in Mölnlycke, outside Gothenburg.