As a specialist in precision centreless grinding since 1981, Stourbridge based Microplus Engineering Ltd diversified into CNC sliding head turning more than 15 years ago – now the company has invested in two new turning centres from Miyano.
The manufacturer previously had two ageing Miyano turning centres that, at the age of 30 needed replacing. When it came to finding replacements, the company again opted for Miyano. “The old machines were still going strong, but it just came to the time where they had to be upgraded. More Miyano’s were the obvious choice,” says Microplus Engineering’s Adam Marshall.
The West Midlands subcontract manufacturer purchased two Citizen Miyano BNA42 turning centres, each with a slightly different configuration. As Adam continues: “Both machines are 42mm. We have the BNA42 SY5 and the BNA42 DHY3. The BNA42 SY5 has a twin spindle with a single 12 station tooling turret with all stations driven whereas the BNA42 DHY3 has an eight-station main turret, a 6-station sub-turret – and all the tooling stations on the main turret are driven. This gives us the facility to do medium to complex components.”
Referring to specific components produced on the two new arrivals, Adam says: “We have one aluminium component where the batch size is not quite justifiable for a sliding head turning centre, so we moved that to the Miyano BNA42 DHY3. By transferring to this new machine, we are getting shorter bar remnants. Additionally, the Miyano machines are so rigid that our tool life has increased considerably. We are not changing any offsets at all and we can hold 10 to 15µm all day long.”
“On another part for the construction industry that is better suited to a fixed head machine than a sliding head, our previous fixed head machines did not have live tooling, so we had to run the parts on the sliding head machines. A typical bar remnant end on a sliding head machine can be 300mm+. With the barfeed on the fixed head machines, the remnant is from 100 to 125mm. Running our machines 24 hours a day and going through a lot of material, it is a very big saving for us.”
Regarding a third component moved to the new Miyano BNA42 machines from the previous ageing Miyano machines, Adam says: “This turned part is machined in batches of 10,000 to 15,000-off, so it is a job that we could have put on the sliding head machines, but capacity wise, we can never really get the jobs on those machines. So, it came to the stage where we needed to upgrade the Miyano machines to get the components through the workshop faster. We have gone from 2 to 3 weeks turnaround down to 8 days and the parts are coming off the machines a lot cleaner. This is because of the part catching unit and all of the automation.”
One of many factors in this reduced lead time is the kinematics of the new Miyano models, as Adam says: “The tip to tip times are a lot faster than our old Miyanos. These fixed head machines are getting very comparible with sliding head machines in terms of cycle times.”
“Another issue we used to have with our sliding head machines is that for all of our aluminium parts, every bar had to be pre-ground in our grinding shop over the road. If you take the guide bush out of the equation, I can run standard bar stock on the Miyano machines all day long. Even though we have our bar grinding facility, this is still a very big saving for our business.” Another saving derived from the new Miyano machines for the automotive, hydraulic and agricultural subcontractor is through energy consumption, as Adam states: “The two new machines combined are using less power than one of the old Miyano machines. Effectively, we have two machines for the price of one.”
