There are a couple of common misconceptions amongst some UK precision component manufacturers concerning automation, specifically regarding its application and its limitations.
The first of these ‘myths’ is that automation is really only suitable for high-volume parts production and for part runs of the same shape and size.
The second is that automation is expensive and that return on investment is long and can therefore be difficult to justify.
Innova Design & Build Ltd has debunked these myths.
Hampshire-based precision subcontract specialist, Innova Design & Build, led by managing director, Hugh Watson, isn’t your typical manufacturing SME.
Having previously invested in its first 5-axis machining centre seven years ago and through its more recent acquisition of a Mikron 5-axis machine with integrated work-piece pallet change capability in October 2013, the company has already demonstrated its progressive and positive attitude to investing in the latest advanced manufacturing technologies.
This drive to increase productivity, improve performance and to become, in Hugh Watson’s own words, “...the most efficient machining workshop in the UK”, has now seen Innova invest in a new, innovative automation solution from GF Machining Solutions, comprising a Mikron HPM 450U (5-axis) machining centre integrated with a system 3R (WorkPartner 1+) robot.
The mainstay of the investment is the system 3R robot which is equipped and configured with 14 x Magnum pallets (for larger parts) and 110 x Macro pallets (for smaller parts).
The machine, robot and associated cell management software, were installed at Innova’s Emsworth facility in December 2014.
Innova and automation
Innova manufactures complex, high-precision parts for the aerospace, marine, rail, space and electronics sectors.
Parts are machined from a variety of materials (e.g. aluminium through to plastics etc), and parts manufacture is characterised by short production runs (prototypes and one-offs through to small-to-medium batch sizes), with short cycle times.
The emphasis throughout is on part quality, quick turnaround and short lead time fulfilment.
This type of manufacturing has resulted in Innova embracing, and becoming experts in 5-axis machining.
Says Hugh Watson:
“We invested in a Mikron ‘Vario’ 5-axis machine, equipped with a 7-station work-piece pallet changer and 220 position tool changer, in 2013.
“Since being installed the machine has been working around the clock (overnight and at the weekends) and has helped us dramatically improve our productivity and make us more efficient.”
However, as impressive as the Vario’s performance was and is, Hugh Watson could see that Innova’s machining processes and performance could be further improved by investing in a more ‘sophisticated’ automation solution.
Continues Hugh Watson:
“There are 168 hours in a week and from experience we know that a significant percentage of these hours can be ‘wasted’ performing non-profitable operations e.g. job set-ups etc.
“Multi-axis machine tools and their ability to produce parts in one hit can clearly help the situation and machines with integrated work-piece pallet changers help increase a machine’s productivity and efficiency too.
“But, even with this type of capability at one’s disposal, productivity is limited by the number of pallets and by the number of tools available on a machine.”
The desire to make every hour in the day as profitable as possible not only provided the catalyst for Innova’s latest automation investment but also spearheaded a different organisational approach to work - designed to get the most from the investment.
For Innova that means that during the normal eight hour day shift all efforts are directed at ensuring that the new HPM 450U and WorkPartner 1+ are able to run unattended overnight. (On Friday afternoons the machine and the robot are set-up to run non-stop over the weekends).
To ensure that this occurs, the focus during the day is on performing a range of preparatory tasks that include:
• Designing and making complex and ingenious fixtures for 5-axis machining of the parts;
• Creating, testing and storing the machining programmes complete with all machining data, that will be used to machine the parts;
• Setting up the jobs on the robot’s Magnum and Macro pallets, and scanning them into the automation management database for quick retrieval and use;
• Planning the machining schedule (i.e. which jobs will be machined, and the order they will be machined etc).
One might think that another preparatory task required for long, non-stop runs involving the machining of many different parts would also require time to be spent loading and unloading tools into the HPM 450U’s tool magazine. However, because the machine has a large-capacity tool changer (220-position), tools can be left (effectively stored) in the magazine and are therefore always ready for when they need to be called into action in the future.
Continues Hugh Watson:
“To exploit our automation investment’s full potential requires a different mindset from everyone in the company.
“The ‘normal’ way of machining a batch of parts to completion in one go isn’t necessarily the most effective or efficient method. As long as we never lose sight of our customers’ delivery schedules we have the freedom to organise and schedule jobs imaginatively to increase our productivity and profitability.”
Because the objective is to constantly maximise and realise the cell’s productivity potential, batches can often be split up in order to keep the machine cutting (unattended) for the maximum amount of time.
This can mean that say a batch of five parts could be machined to completion one after another.
However, it could also mean that the five parts are machined separately over a period of time, or that they are only partly machined and are completed the next day or the day after. Automation has therefore given Innova the freedom to squeeze every ounce of productivity from its HPM 450U machining centre.
Although only installed a couple of months ago the new automation investment has delivered impressive results. In one particular week the HPM 450U and Work Partner 1+ were set up on a Wednesday and ran non-stop until the following Monday, machining a number of different jobs to completion or part completion, during the period.
As members of staff become more familiar and confident with the technology, it is anticipated that non-stop operations will become the norm.
As far as the previously mentioned myths are concerned it’s clear that Innova is making automation work for small-to-medium batch production, and that if the company is able to maintain its operation of the system somewhere approaching 20 hours a day/6 days a week, payback will be achieved significantly sooner than was first thought.
The automation solution – in more detail
The Mikron HPM 450U is a versatile, high-performance 5-axis machine equipped with a 12,000/20,000rpm spindle, a direct-drive rotary tilting table (B-axis tilt = 120 ° /+ 45 °; C-axis = n x 360 ° and a 220-position automatic tool changer).
The machine, described as ‘universal’, is compact with a small footprint and can be used for 5-side and full simultaneous 5-axis machining.
The system 3R WorkPartner 1+ robot is a compact, modular and flexible automation unit for changing pallets, and is ideal for both one-off and series production.
The robot provides reliable and rapid pallet storage and pallet change capability and can be configured to handle ‘light’ and/or ‘heavy’ pallet magazines.
The automation solution is driven and controlled by powerful cell management software used to manage the automatic loading/unloading of parts into the machines, record the machining time of each job etc.
The core of the system is an efficient database that uses chip identification of the pallets to ensure that the correct machining data is being used for the correct parts.