The full potential
McConnel, the UK-based manufacturer of vegetation maintenance solutions is no stranger to working with high strength steel. Now, the company has taken their use of this material to a completely new level by developing a product never before seen on the market – or even thought possible.
First on the market
McConnel launched the first ever tractor-mounted hedge cutter back in the 1940s. Since then, they have been at the forefront of their field when it comes to innovation. So, when their Dutch distributor approached them in 2016 with an idea for a new compact Variable Forward Reach (VFR) hedge cutter, McConnel decided to build if from scratch – and from performance steel.
“A Variable Forward Reach arm on a hedge cutter provides better stability on sloped ground as well as improved operational efficiencies, given the longer reach. There is also no need for swapping tractor units for difficult cutting operations,” explains Arnaud Henry Lefort, Design Engineer at McConnel.
This new VFR would have to be compact and light enough for smaller tractors to use efficiently when trimming vegetation on small carriageways and bike lanes. Therefore, obtaining the right structural stability and torsional rigidity, while using lightweight materials would be the major challenges.
Understanding the possibilities
For assistance in choosing the right grade of steel and the design, McConnel turned to SSAB.
“McConnel is a long-time SSAB customer, and for this development project, they attended many seminars to gain knowledge about what is really possible with high strength steel,” explains Aaron Middleton, Tech Support Special Steels, SSAB. “For the design concept, we looked to known principles based on the technical literature, focusing in on an optimal shape, and then identified the right steel.”
Strenx® 700 MC Plus was chosen as the most optimal grade for the boom and auxilirary structures, based on its excellent formability, which enabled the optimized shape to be realized. The areas exposed to wear, in the vicinity of the flail head, are made from cold-rolled Hardox® 450.
“The complexity of the design required that we needed to get the tooling correct and the welding order was critical,” says Henry-Lefort. “It was a challenging process, but the result is worth it – and could not have been done without high strength steel.”
The end result was the PA 4830 VFR, a hedge trimmer with excellent compact dimensions and impressive performance.
“The weight of an older arm solution was 530kg compared to 450kg for the new PA 4830 VFR, which also provides a half meter more of variable forward reach,” explains John Frank, Engineering Manager at McConnel. “This also means that we can put the machine on a smaller tractor, which is more economical in terms of fuel efficiency. Overall, there is also less steel used.”
My Inner Strenx® approved
The fact that the new hedge trimmer fully utilizes the potential of Strenx® and Hardox® steel from SSAB helped it to be accepted into SSAB’s My Inner Strenx® program.
My Inner Strenx® is a program for manufacturers who possess the drive to make the best possible products using Strenx® performance steel. It allows for better access to support from SSAB and is a way for operators and end users to identify producers and products made with superior steel and quality-controlled production techniques.
McConnel’s new VFR was launched at the Agritechnica 2017 show in Hamburg and it received very positive feedback. Long-term testing with some customers has also confirmed interest, and orders have already been received.
“We appreciated the support as well as the quality of the steel from SSAB,” explains Frank. “Otherwise, it would have been difficult to realize.”