Helical Adds Compact Nakamura to Plant List
It’s not every day you find a manufacturer with its own museum, but such is the passion for manufacturing at Helical Technology Ltd that the company has a locomotive, a Red Arrow and a Bluebird replica among other artefacts at one of its four facilities. This passion for manufacturing, precision and quality is why the company has added yet another Nakamura-Tome mill/turn centre from the Engineering Technology Group (ETG) to its plant list.
Established by company Chairman James Morris in 1962, the family business is a leading manufacturer of valve rotators that are used in marine, locomotive, mining, automotive and power generation sectors. The Lytham based company undertakes the complete design, manufacture, assembly and testing of its products that also include prototype exhausts for high-performance vehicles and actuators for leading OEMs worldwide.
The valve rotator division was founded in 1987 and today, it produces more than 120 different assemblies with over 4 million assemblies expected to be completed in 2023, making a sizeable contribution to the company’s circa £35m turnover. Large volume production is conducted off-site with volumes up to 1000-off produced at Lytham – it is here that Nakamura-Tome machines from ETG are delivering results.
Nakamura-Tome CNC Machines
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 1000-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 recalls: “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 we added to it 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.”
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. Commenting upon the arrival of the latest machine, Helical Technology Production Manager Mr Jonathan Rigby says: “We had an ageing single spindle single turret machine that was having reliability issues. The machine got to a point where instead of outlaying on an expensive repair, we bought the Nakamura AS200MYS. The purpose of the machines was to accommodate our billet work whilst our other machines are utilised 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 2000-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. Commenting upon this, Jonathan says: “The outgoing machine was a larger footprint than the Nakamura and it had a barfeed that we didn’t need. We wanted a compact heavy-duty machine with a spacious work area and the Nakamura AS200MYS has certainly provided that.”
Performance and Productivity
From a performance perspective, the Nakamura AS200MYS has accelerated productivity. As Jonathan adds: “The typical cycle time is 6 minutes 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 a minute off the cycle time. With the number of parts going through the Nakamura, this adds up to a major reduction. This 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 massive 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.”
“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. Whilst 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,” adds Jonathan.
Discussing the service the company receives from ETG, Jonathan concludes: “When our old machine was beyond repair and we couldn’t use it, 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’ whilst we were waiting for the Nakamura. ETG are very supportive and will always endeavour to support our business in every way possible.”