Danish company HACO A/S invested over $15 million in five Dörries vertical turning lathes (VTLs) from Starrag, Rorschach, Switzerland, which has helped HACO become the leading sub-contractor for large, relatively flat and round components in its Scandinavian location.
Founded in 1966 and located in Barrit, Denmark, in the middle of a small, low-lying peninsula, HACO produces extremely large, rotationally symmetrical parts for companies such as Siemens Wind Power, Vestas, Valmont SM, LM Windpower, KHS and MAN Turbo. The company processes about 11,000 metric tons of steel per year into extra-large parts at a high level of vertical integration (including welding) on the large Dörries VTLs. Nitriding is one of the few jobs performed externally, such as nitriding the contact surfaces of highly stressed drive elements for wind energy systems.
The company’s DIN ISO 9001 certification shows this “job shop” also develops components itself. This service is very popular with regular customers from the wind power sector and the offshore industry, who commission the company to produce impellers or molds for wind vanes and components for ship engines or bottle filling systems.
HACO’s EN ISO 14001 environmental certification affirms that this work is also done in an ecologically sound manner under the company’s own environmental management system. This attitude is also reflected in its new machines, which are all fitted in complex housings that protect employees against noise and aerosols (a mixture of air and very finely distributed solid and liquid particles).
Judging by HACO’s pool of machines, one thing is for certain—in this part of Denmark, size matters.
“Our latest Dörries vertical turning lathe was designed for components with a swing diameter of up to 21' (6.4 m),” said HACO Managing Director Henning Albrechtsen. “We have extended this to 24' (7.3 m), pushing the technical limits of a machine tool.”
HACO’s entry into the world of extra-large machines began in 2000 when it bought a large, used lathe manufactured by Schiess and immediately received its first major order. Around the same time, Albrechtsen contacted Starrag, who took over the retrofitting of these production systems and then later retrofitted two more Schiess lathes. Now, Albrechtsen is following the same recipe for his other investments. “We always have to have the machine first so that we can then get the orders,” he said.
HACO is now home to 11 vertical turning centers in various sizes (with a swing diameter of 5-24', [1.5-7.3 m]), and almost half are from the Dörries product line. One of these machines is used and four are new (Dörries VC 2500, 3500, 4500, 6000 and 6500). HACO produces almost everything on these machines in a single clamping position. As Hubert Erz, Dörries sales manager, said, “This shows that investment pays off—it’s not the price of the machine that matters, but the costs per part.”
“We have had a very good experience with Dörries machines when it comes to quality, precision and service,” said Albrechtsen. However, he believes the good reputation of the Dörries brand also plays a crucial role—for instance, when the company is being audited by inspectors from potential customers, or certified by auditors.
For Dörries, sub-contractors pose a particular challenge. “It’s about keeping the level of investment, and thus the machine hourly rate, low so that the ‘job shop’ can sell its services effectively,” explained Erz. “A very high level of flexibility is also required so that the sub-contractor is able to adapt to a wide range of orders. It’s a difficult balancing act.”
Thanks to its pool of machines, the family-run HACO can produce components with a maximum diameter of 24' (7.3 m) and a height of more than 9' (2.7 m) in a single clamping position—and at hundredths of an inch in precision.
“Companies that have vertical turning lathes are already operating in niche markets in comparison to production facilities for cubic workpieces,” said Erz. “And then there is also the issue of size and quality. That’s why subcontractors like HACO are a rarity.”
The concept has been a success. HACO has received larger orders spanning a period of years. These orders enable the company to purchase systems with a higher level of automation, which in turn helps to make its production process more efficient and cost-effective.
HACO also enjoyed a stroke of luck when it purchased a new Dörries VC 4500 fitted with equipment to a very high standard. A major corporation had commissioned the machine in order to manufacture large components for wind energy transmission systems, but no longer needed it.
At HACO, the 11 machines are now used in producing individual pieces as well as parts in batch sizes of 100. Albrechtsen believes that a highlight of his work is that highly demanding customers tend to consult HACO, sometimes early on in the project development phase.