Summary: This article explains the benefits Ishida derived from the purchase of Hurco machining centers, which made it more cost-effective to move its manufacturing in-house. The machine shop personnel and managers point specifically to Hurco control features that have increased their productivity—features, such as Patterns, DXF Transfer, Concurrent Programming, NC/Conversational Merge, the overall speed and usability of the WinMax platform, and Conversational Programming.
UK machine shop pioneers Japanese group's in-house manufacture
Article originally appeared in Packaging Europe Magazine
The Japanese, family-owned Ishida group is a giant in food packaging machinery, with a worldwide turnover in excess of half a billion Euros. Perhaps surprisingly, almost all of the component parts that go into its automated weighing, filling, packing, handling and inspection equipment are made by subcontractors, while assembly is carried out at Ishida factories in Japan (Shiga prefecture), Korea, China, Brazil and the UK.
Group policy on subcontracting is about to change, however, largely due to the success of a UK subsidiary in Poole, Dorset, and its use of four Hurco machining centres. Here, 80% of components are produced in-house for a new range of semi-automatic traysealers. Prototype parts are also machined for larger in-line traysealers assembled at Ishida Europe's headquarters in Birmingham, while customers' bespoke traysealer tools are designed and manufactured in Poole.
In the long term, core production of traysealers will be brought in-house in its entirety, with just very simple parts and seasonal over-capacity subcontracted. The main advantage to Ishida will be faster lead-times. Other benefits are an enhanced ability to control component quality as well as scope for making higher margins by reducing subcontracted machining costs.
Despite the recession in many European countries, the demand for traysealer tools has been increasing over the years, as consumer demand for pre-packed fresh meat and ready meals has been on the rise. This had led to a demand for high-speed packing lines and larger sealing tools to help food processors and packers meet the demand.
The requirement to mill and drill these larger tools, mainly of C250 aluminium but sometimes 304 stainless steel, which can be over a metre long and weigh in excess of 300 kg, prompted Ishida Poole to purchase its first Hurco vertical machining centre (VMC), a VMX50t, in 2009. Until then, the company had relied on other, smaller capacity VMCs.
Chris Witheford, Production Manager, comments, "We noticed that a local subcontractor to whom we regularly give work uses a similar Hurco machine.
"I was particularly impressed with the ease of programming using the supplier's conversational software, WinMax, which is a Windows-based suite running on Hurco's twin screen control.Our tooling designs are based on core templates containing lots of repeating holes and pockets which need to be copied, sometimes rotated and pasted elsewhere .For this, the pattern location functionality within WinMax is ideal and saves a great deal of time. This is important to us, as batch sizes here are typically ones, twos and threes, so programming takes up a large part of overall production time."
David Nielsen, machine shop team leader at Ishida Poole, agrees: "WinMax is at least three times quicker at creating programs than the conversational control on our previous VMcs, some of which are still in use for making spares and on which the control systems employ Q-def programming. The latter tend to be laborious, whereas WinMax is more user-friendly."
According to Hurco, WinMax controls can be used to prepare programs simultaneously while a component is being machined. A graphic of the component is visible on the right hand screen as the cutting paths are being created. At the end of the process, the entire cycle can be simulated to ensure that there are no interference issues.
This is particularly important when machining small batches, as a single scrapped part could be a high proportion of total production. The twin screen also improves staff confidence when running the program, bearing in mind that 80 to 90% of solid material is removed to make a tooling plate. Cycle times vary from around one hour for an insert up to a full shift to machine an entire plate.
Mr Nielsen continues, "A valuable feature of the Hurco control for 2D programming is that it accepts DXF files directly from our SolidWorks CAD system.
"One tooling plate might contain 120 holes and it is very time-consuming and error-prone to key in the hole centres individually by hand, whereas WinMax picks them up automatically from the DXF data.
"When we have 3D elements to program, like the front heater plate profile for a tool, we find it quicker to prepare those blocks in a OneCNC CADCAM package and add them to 2D elements written conversationally in WinMax, using another of its useful functions, NC Merge."
All of the machine tools on the shop floor, which now include a further Hurco VMX50t and two smaller VMX42t machines purchased at MACH 2012, are networked to a server at Poole, together with the CADCAM systems. Mr Nielsen adds, "Compared with programs previously written conversationally using other controls, those generated in WinMax are more standardised and clearer, which is an advantage for networking."
The result is seamless transmission of program data and tooling lists, ensuring that any Hurco machine can produce any part (subject to size compatibility) with minimum delay, creating a lean production environment. Four operators, two fewer than previously, run the machine shop despite there being more CNC machine tools, currently seven.
The specification of all the Hurco VMX machines includes a 12,000 rpm spindle with a chiller for high speed cutting of aluminum, a dual-wound motor to provide high torque at low revs when machining stainless steel, and an 8-jet coolant ring for flooding the cutting area to remove chips efficiently.
The four Hurco VMXs at Ishida Poole have transformed the company's approach to prismatic machining and allowed it to take cost out of production. That is important, as the site is a cost centre within the group and constantly takes buy-or-make decisions based on the price of producing a part in-house compared with how much a subcontractor would charge. Invariably, the internal production cost is lower, which fits with the firm's aim of bringing more of its manufacture in-house.