The latest Nakamura machine at Helical Technology offers a robust platform with a compact work area

It is not every day you find a manufacturer with its own museum, but such is the passion for manufacturing at Lytham-based Helical Technology Ltd that the company has a train, a Red Arrow jet and a Bluebird replica among a number of artefacts at one of its four facilities. A passion for manufacturing, precision and quality is why the company has added yet another Nakamura-Tome mill/turn centre supplied by the Engineering Technology Group (ETG) to its plant list.

Established by company chairman James Morris in 1962, the family-run business is a leading manufacturer of valve rotators that are used in the marine, locomotive, mining, automotive and power generation sectors. The company can undertake the complete design, manufacture, assembly and testing of its products that includes prototype exhausts for high-performance vehicles and actuators for leading OEMs worldwide.

The valve rotator division was founded in 1987 and today produces more than 120 different assemblies with over four million assemblies expected to be completed in 2023, making a sizeable contribution to the company’s £35 million turnover. Large-volume production is conducted off-site with volumes up to 1,000-off produced at Lytham – it is here that Nakamura-Tome machines from ETG are delivering significant results.

The machine shop has 21 turning centres that include both single- and twin-spindle machines with some Y-axis capability to primarily produce 16MnCr5 steel components in batches up to 1,000-off per week. The 21 turning centres have been provided by a multitude of brands over the years, but when one of the largest and most prestigious brands in the world let the company down badly, Helical turned to ETG and its Nakamura machines.

The company started with a Nakamura-Tome WT150II in January 2020 and its success was built upon with a second WT150II and then a NTY3-100 twin-spindle triple -turret machine. As operations manager Chris Waddington recalled: “The difference with the WT150II compared to existing machines was ‘night and day’. The cycle times were 5 to 10% faster than the other leading machines that we had bought, but it was just everything else about the machine. The Nakamura was more stable, robust, user-friendly and easy to set up and use. So, we bought a second machine and then added to it further with the NTY3-100. We have some of the most productive machines in the industry, but the NTY3-100 instantly took 20-25% out of our cycle times.”

highly-productive solution
With floorspace at a premium, the company followed the initial purchases with a smaller Nakamura AS200LMSY and earlier in 2023, this was followed by another Nakamura, the AS200MYS. Jonathan Rigby, Helical Technology production manager, said: “We had an ageing single-spindle single-turret machine that was having reliability issues. The machine got to the point where instead of engaging in expensive repairs, we bought the Nakamura AS200MYS. The purpose of the machines was to accommodate our billet work while our other machines are used for production runs. We wanted a compact, robust and highly-productive solution and once again, ETG delivered.”

Purchased to machine a family of steel valve rotator parts, typically in volumes from 200 to 2,000-off, billets are manually loaded in the Nakamura AS200MYS where turning and heavy-duty milling are undertaken. The parts are then re-loaded for secondary finishing.

Mr Riby added: “The outgoing machine had a larger footprint than the Nakamura and it had a bar feed that we didn’t require. We wanted a compact heavy-duty machine with a spacious work area and the Nakamura AS200MYS has certainly provided that. The typical cycle time is 6min per set up and the Nakamura is improving our productivity by at least 15 to 20% compared to its predecessor. The kinematics of the machine are reducing travel and ‘fresh-air’ cutting which is shaving at least 1min off the cycle time. With the number of parts going through the Nakamura, this adds up to a major reduction. The saving is achieved through heavier cutting cycles that are credited to the rigidity and stability of the AS200MYS. On milling cycles, we are witnessing a significant reduction in cycle times. On one sleeve part we produce, we can now take a 5mm depth of cut compared to 3 to 4mm on the previous machine.”

He continued: “There is less deflection and vibration and our surface finishes are greatly improved. We can machine straight in at 5mm depth of cut with no need for a finishing pass, the stability and performance of the Nakamura is that good. While we have not undertaken a feasibility study on tool life on this machine, we know that we can machine more parts per tool and this is undoubtedly reducing our tooling consumption and costs.”

Discussing the service the company receives from ETG, Mr Rigby concluded: “When our old machine was beyond repair and we couldn’t use it any more, we needed a replacement urgently. With a short delivery lead time on the Nakamura AS200MYS, ETG loaned us a Vulcan turning centre as a ‘stop-gap’ while we were waiting for the Nakamura. ETG are very supportive and will always endeavour to assist our business in every way possible.”