A trio of Bumotec multi-axis, multi-tasking machining centres are helping Shanghai Medical Instruments (Group) to maintain its 50% market share in China for medical instruments. Moreover, the ability to finish-machine up to six faces at high accuracy and in a single set-up, have enabled the company to expand profitably into the manufacture of minimally-invasive instruments and devices.

Indeed, while the effectiveness of the machines at single set-up multi-operations has brought great rewards in both prototyping and manufacture, the company highlights its latest Bumotec – the five-axis s181 model with ‘front live tools’ on a sub-spindle – as being able to boost productivity by 20% on some parts.

Capable of producing complex, multi-faceted components from bar up to 65 mm diameter, and with up to seven-axis simultaneous machining in a single set-up, Bumotec machining centres are capable of drilling, thread forming, grinding, gear cutting and broaching, in addition to turning and milling. According to Starrag, the machines are renowned globally for producing small, intricate workpieces that come off ready for assembly with no deburring – as Shanghai Medical Instruments has found.

A member of the Yuwell Group, the company has four production plants in the Shanghai area; three manufacturing/assembly facilities and one site dedicated to forging, surface finishing and heat treatment. Established in 1928, Shanghai Medical Instruments annually manufactures over 10 million parts for use by hospitals throughout China and in other countries. Components are produced in limited batches of 200-300-off, with the company’s in-house manufacturing routines complemented by a group of subcontractors. In addition, there is an in-house team of 20 quality control engineers.

Shanghai Medical Instruments has a product catalogue of more than 8000 items, which includes its flagship, award-winning JZ brand. Key products include knives, scissors and surgical clamps, as well as 400 different types of micro instruments for anastomosis, the treatment of lymphatic vessels and limb reconstruction.

Its portfolio also embraces instruments for ENT surgery, orthopaedic implants and 300 types of minimally invasive instruments such as laparoscopic clamps (used in endoscopy procedures) plus 400 instruments for dental surgery. Surgical staplers and electrical tools used in surgery also form part of the portfolio.

The development of so many different products is based on close work with hospitals and universities, and the company’s R&D team collaborates with these ‘partners’ throughout the entire new product development process, from design, studies and validation, up to production. Shanghai Medical Instruments’ well-equipped workshops allow the process to be flexible and responsive, and the prototyping and production of certain parts is a key area for the Starrag-supplied Bumotec machining centres (models s192, s181, s191), the first of which was installed in 2005.

A range of 500 different types of minimally-invasive and ENT instruments are machined in a single set-up from bar on the Bumotec machining centres. Over the years, the company has found that ‘conventional’ separate processes/machines are not able to produce these components effectively, especially in terms of quality and the issue of ‘matching’ parts and features. Also, the multiple complex clamping procedures required for the various stages of machining make traditional production slow and inefficient.

Bumotec machines, on the other hand, can produce complete components in a single clamping from bar stock, finish-machining up to six faces in record time – in one case, up to 20% quicker.

In fact, even the production of separate parts (on the same machine) for an orthopaedic instrument assembly meets the company’s stringent quality standards. The two-part assembly is now produced with high accuracy, ready for assembly and more cost-effectively by a Bumotec s191, rather than the former route of using a lathe, a mill then an electrical discharge machine to finish the parts to the required standard.

Starrag’s Bumotec s191H can achieve highly accurate (±2.5 µm) machining solutions within its X-, Y- and Z-axis range of 410, 200 and 400 mm, respectively, courtesy of linear drives and high-level thermal stability. In addition, a sub-spindle can turn in both horizontal and vertical planes for multi-process/tasking routines. Tool magazine options extend to up to 90 pockets on a machine that offers rapid traverse rates of 50 m/min and a 30,000 or 40,000 rpm spindle, which also contributes to fast cycle times.

Another example concerns the production of an instrument for ENT surgery. This part is produced on a Bumotec s181 in eight minutes, instead of 10 minutes by former methods, thanks to the simultaneous use of the machine’s sub-spindle.

The company continues to invest in Bumotec because, it says, “the machines’ stability in production is extraordinary, and their ease-of-use makes them accessible even to the newest members of our production team”. Also, when installed, “the training supplied means we can get the machines into production very quickly”. Shanghai Medical Instruments adds: “Production changeovers are quick and easy, and maintenance routines are effective and efficient thanks to Starrag’s excellent customer support.”

Commenting on how the success of Bumotec machines can be mirrored by UK medical manufacturers, Lee Scott, Starrag UK’s director for sales and applications, says: “The UK medical manufacturing market is an important sector for Starrag and, underpinned by our engineering applications knowledge, we know that Bumotec users can ‘hit the ground running’ in terms of gaining production efficiencies.”

For further information
www.starrag.com

Automatic nesting capability in Radan CADCAM software is achieving a sheet-metal subcontractor’s target for its raw material utilisation as part of its ‘smart factory’ vision. Alpha Manufacturing provides a full range of sheet-metal services across a number of sectors, including automotive, agricultural, healthcare, retail and electronics.

The company was established in 1989 specifically to manufacture products for its sister company, Bri-Stor Systems, which had been set up six years previously. Bri-Stor is a specialist in light commercial vehicle conversions, supplying internal racking, roof equipment, on-board power and accessories.

Bri-Stor and Alpha Manufacturing share a 35-acre site at Hixon, Staffordshire. The former’s solutions comprise consultancy and design, through to in-house manufacture, installation and livery application. Customers range from those with just a few vehicles, to hundreds, and include many well-known UK fleets.

Modular products for standard conversions include options designed for particular sectors, while bespoke solutions create kits which are fully customised around the specific needs of the customer’s fleet. For example, the Vantage range is an innovative storage system that maximises the usable space within the van. Unlike most internal racking systems, this features an asymmetric design which allows up to three times more tools or materials to be stored.

Initially Bri-Stor outsourced its sheet-metal fabrication requirements, before the decision was taken to build up its own manufacturing arm with Alpha Manufacturing.

Alpha’s marketing manager Chris Kidney says: “Originally we were dedicated to producing the van kit-out components for Bri-Stor, but fast-forward to today, and we now have a large portfolio of subcontract work, which actually outweighs our Bri-stor production.”

All components for both sides of Alpha’s business go through the dedicated sheet-metal CADCAM software, Radan, from Hexagon Manufacturing Intelligence. Kidney says it is extremely important that the parts are high precision, often needing to be within ±0.2 mm. The process begins with laser cutting and punching on Trumpf, Bystronic and Pullmax CNC machines programmed with Radan tool paths and nests, before moving through the factory for folding, fabrication, welding, powder coating and assembly.

“Our biggest challenge was meeting customer deliveries on time, which Radan overcomes with its speedy programming, and by nesting components for individual van conversion kits on the same nest,” explains Kidney.

The company’s team of three full-time programmers makes full use of Radan’s nesting functionality, analysing the true shape, material and thicknesses of all components in a batch, separating and sorting automatically, to produce manufacturable, high-utilisation nests both from full sheets and offcuts.

Says Kidney: “As there’s no limit to nesting components of different sizes and shapes onto different materials and thicknesses, this delivers substantial material savings and improves machine efficiency.”

When the nests have been finalised and are ready for cutting, two of Alpha’s machines – a Trumpf TruPunch 6000 laser-punch combination machine and a Trumpf S12 punch press – can both feed off a Stopa automated storage system which leads to even greater efficiency and time savings. The entire Stopa system now runs 62 m down the centre of the factory, and contains 230 pallets capable of storing a total of around 600 tonnes of sheet metal. This automated system manages the process of stock storage and movement between machines, with all raw sheet metal stored in the towers from where it can be retrieved at the touch of a button.

Programming manager Mark Clews takes up the story: “At the very start of the process, our design team are given a SolidWorks drawing which they break down into a DXF file. This is then imported into Radan. The programmers open the file, along with the nesting works order, which tells them exactly what requires programming. They put that into their nesting schedule; sorting it into parts of the same thickness and those of different thicknesses. The tool paths are applied at the nesting stage to maintain the quality and integrity of the parts, while optimising the cutting sequence, enabling the machine tool to attain its full potential.”

Kidney adds: “The fact that we can process the parts extremely quickly from initial design to getting them on the shop floor ready for machining, has a significant effect on delivery times to Bri-Stor and subcontract customers, which in turn, improves our profitability.

“We’re currently pushing towards automation, high efficiency and lean manufacturing,” he continues. “The focus of this plan is on utilising high-tech machine automation to realise a ‘smart factory’ vision. Today, close to £4m has been invested to secure Alpha’s position as one of the most technically advanced factories in the industry. The Stopa storage system is a major part of that, and Radan plays a vital role with quick, powerful automatic nesting and good sheet utilisation.
“We have a standard procedure that every sheet we nest must be utilised to a minimum percentage. And we achieve that, thanks to Radan.”

For further information
www.radan.com

It was as recently as 2012 that manual plus two-and-a-half-axis CNC milling gave way to full 3D machining of plastic injection moulds on a three-axis vertical machining centre at family-run tool maker and plastic injection-moulding specialist Plasticom Group. Since that time the tool room has undergone a transformation, with 2020 alone seeing investment of £250,000, mainly for the purchase of a Sodick die-sink EDM machine and a German-built Spinner three-axis machining centre from UK sales agent Whitehouse Machine Tools.

The arrival of the latter machine at the end of September 2020 coincided with the departure of a 25-year-old CNC milling machine. It fell to tool-room co-ordinator Ian Alexander to investigate the best replacement for machine. In total, he scrutinised three machines before selecting the Spinner due to the comprehensive specification of the standard version of the VC750.

Spinner’s VC750 machining centre includes linear scales, 22 bar through-spindle coolant, a swarf conveyor, Blum TC52 spindle probing, a 24-station BT40 tool magazine, a 12,000 rpm spindle, Siemens drives with up to 36 m/min feed rate and the latest Sinumerik 840D control with 24-inch Industry 4.0 multi-touch display. Alexander says that the equivalent package from other suppliers would have cost half as much again.

“The VC750 represented the best value for money by far, and the latest Siemens control is a real bonus,” he states. “It allows us to program cycles to produce complex forms directly at the machine, taking the load off our CADCAM department. We also like the rigid, cross-table, C-frame design, which results in superior cutting performance and component geometry. The ability to probe a part before it comes off the table and re-machine it if necessary is a big time-saver and makes us more competitive.

“The Spinner is between 30 and 70% quicker than our other VMC, depending on the type of component,” he continues. “I should say it halves cycle times on average due to faster axis movements, the extra rigidity – which allows heavier cuts to be taken without causing vibration – and the latest Siemens control. It offers so much more productive capacity that there will be a lot of spare time to take on additional subcontract machining, which at present accounts for only a few percent of turnover.”

Operating from a factory of nearly 20,000 sq ft in Ashford, Kent, Plasticom has long-standing, high-profile customers that include household names such as Stanley Black & Decker, Games Workshop, Qualcast and Swann-Morton, as well as a host of smaller firms that call on its services. The company was invited in March to be part of the UK Government’s Ventilator Challenge UK consortium, and staff worked long hours under considerable pressure to ship 15,000 plastic ventilator parts to McLaren Racing against a very challenging schedule.

The company is ISO13485 accredited and has a class 7 clean room for the assembly of medical devices. Plasticom Group’s plastic injection-moulding capacity utilises machines rated from 20 to 530 tonnes, including automation, and extends to twin-shot moulding and over-moulding. The manufacture of press tools, vacuum forming tools and die-casting tools also forms part of its remit, while other services include ultrasonic welding, blister and other packaging techniques, and laser welding and printing.

The 60-years-established company is owned by chairman Edwin Simmonds and his wife, Sonia, group finance director, who says: “More than four-fifths of the injection mould tools we make are used in-house to produce a wide range of parts for customers, a side of the business that accounts for a similar proportion of our turnover. Keeping the moulding section operating is therefore critically important, so we look to our machine-tool suppliers to provide prompt aftersales back-up.

“The service that we have received so far from Whitehouse has been excellent, both in terms of the technical input and the training,” she adds. “Our shop floor staff have had one week of tuition so far but no limit has been placed on the amount we will receive in the future, free of charge, which is unusual and a great reassurance.”

Alexander has adopted a policy of buying in bolsters from Meusburger to allow Plasticom to concentrate on the 3D milling and sparking of tools. A fixture sits permanently on the table of the Spinner VC750 so that operators can quickly clamp each new bolster prior to the machining of mould inserts within the 760 x 460 x 460 mm working envelope, which is large for the machine’s 2.6 x 1.7 m footprint.

He also advises that dimensional tolerances down to a few microns are routine and that the surface finish achieved is “fantastic”. In aluminium, as well as Stavax, a mirror finish is achievable using standard, mid-price, carbide end mills, requiring considerably less polishing overall.

For further information
www.wmtcnc.com

Mills CNC, the exclusive distributor of Doosan machine tools in the UK and Ireland, has supplied Quick Machining Solutions, a precision subcontract specialist based on the outskirts of the New Forest, with a new vertical machining centre. The machine, a Doosan DNM 4500 three-axis machining centre, was installed at Quick Machining Solutions’ refurbished 7000 sq ft facility in September 2020.

Investing in a new machine tool during the pandemic, at a time when many manufacturers were “battening down the hatches” has helped Quick Machining Solutions meet growing demand for its machining capacity and capabilities.

Explains Wayne Harris, owner and managing director: “A number of component manufacturers closed down their operations and/or furloughed a significant number of staff in response to the pandemic. We felt that even in these uncertain times, we had an obligation to remain open while ensuring we did everything to keep our staff safe. We also used any spare time for training, maintenance and other improvements within the business.

“As a consequence of keeping our doors open we were able to pick up new work from a number of customers who were having difficulty sourcing their machined parts in the necessary timescale,” he continues. “This increase in demand, in addition to continually improving our machining capabilities, was the main catalyst behind the DNM 4500 investment.”

To ensure that the new machining centre would meet its immediate and future production requirements, the company drew up a checklist and investigated the market.

“We needed a high-performance three-axis machine with a compact footprint and a good-sized working envelope to handle a wide range of different-sized parts,” says Harris. “Also, we required a machine with a Heidenhain 640 control to integrate with our existing database of machines and programs.”

He adds: “We’d looked at purchasing a Doosan DNM 4500 at the start of the year but had postponed the decision, temporarily as it transpired. However, the increase in demand and the need for swift delivery, combined with a great purchase price, meant that the investment was given the go-ahead.”

Since being installed, the DNM 4500 has been used to machine a range of components for customers operating in the motorsport, film, leisure and industrial sensor sectors, to name but a few. These parts, machined in small-to-medium batch sizes and from materials that include aluminium, stainless steels, titanium and engineering plastics, often exhibit tight tolerances (down to a few microns in some instances) and surface finishes of Ra 0.1 µm.

The DNM 4500 machine supplied to Quick Machining Solutions is equipped with a direct-drive 12,000 rpm spindle, a 1000 x 450 mm work table, a 30-position ATC and a Heidenhain TNC 640 control. Further features include roller LM guideways and thermal error compensation to ensure high accuracies and repeatability over long machining runs.

Says Harris: “The DNM 4500 is versatile and a great all-round performer. We ordered the machine in September and in the same month it was delivered, installed and cutting metal.”

Founded in 2010, Quick Machining Solutions has achieved significant growth and success over the past 10 years. The company today employs eight members of staff, has substantially increased its turnover and, to win new business and secure its position within customer supply chains, has achieved ISO9001 accreditation. Its commitment to continuous improvement is further reflected in strategic and prudent investment in machine tools and ancillary technologies, as evidenced by its first Doosan machine acquisition around two years ago.

In November 2018 Quick Machining Solutions invested in a Doosan Lynx 2100LMA multi-axis turning centre with an integrated servo-driven bar feeder.

“To maintain our competitive edge we made the strategic decision to invest in a flexible, high-performance multi-tasking turning centre,” says Harris. “We were looking for a lathe that was fast, powerful and accurate, and we were specifically keen on acquiring a machine that was equipped with driven tooling to help us reduce set-up and part cycle times. A bar feeder was also required to help us improve productivity and facilitate ‘lights-out’ and unattended operations.”

Before taking any purchase decision, Quick Machining Solutions did its homework and researched the market. The results revealed that Doosan lathes were popular among component manufacturers and that, for small component production, the Lynx range came highly recommended.

On the basis of its findings, which also included visiting an existing Mills customer and Lynx lathe user, Quick Machining Solutions placed its order for a Lynx 2100LMA.

Says Harris: “The Lynx lathe is a real workhorse and, since its installation, hasn’t missed a beat. The performance and reliability of the Lynx lathe, and the ease of doing business with Mills, were major factors in us deciding to invest in the DNM 4500.”

Investing in new technology as well as its people, plant and manufacturing processes and systems, is definitely the “direction of travel” for the company moving forward. Other recent and planned investments to enhance its performance include: the recent purchase/integration of an MRP system to help improve productivity and operational efficiencies; investment in a new CMM to boost inspection capabilities; the roll out of a plan to generate solar energy; and the continuation of the firm’s in-house apprenticeship programme.

“We’re always looking to improve and innovate,” concludes Harris. “We’ve built a solid reputation in the market based on the quality of our machined components, the fast turnaround times we can achieve for customers and our competitive prices. In a relatively short space of time we’ve become a ‘go-to’ precision component manufacturer for customers operating in number of industries. Our investments in Doosan machine-tool technologies have been more than instrumental in helping us get to where we are.”

For further information
www.millscnc.co.uk

As a global specialist in fluid engineering technology such as pumping, agitation, mixing, separation and application technologies, Sulzer has a network of 180 manufacturing facilities and service centres across the globe. With more than 25 service and manufacturing facilities in the UK; a reliable and reputable supply chain is critical for this OEM and service provider, which is why Sulzer recently committed to a three-year contract with metalworking and MRO experts MSC Industrial Supply Co.

Driven by quality, innovation and continuous improvement, Sulzer witnessed indifferent levels of support from its previous integrator of consumable products and made the bold move to change its supplier during the pandemic. It was only a matter of weeks from signing the contract before MSC was identifying savings worth hundreds of thousands of pounds at Sulzer.

Notably, MSC identified the savings ‘virtually’, during the UK lockdown.

The initial phase of the contract is seeing MSC implement vending solutions into two of Sulzer’s largest UK manufacturing sites in Birmingham and Leeds, with bespoke solutions introduced gradually at Sulzer’s other UK sites.

MSC application engineer Stuart Wiezniak was tasked with identifying ‘cost-down’ improvements to meet and exceed MSC’s contractually agreed commitments. Using its manufacturing expertise, a choice of unbiased suppliers, hundreds of best practice reference points and the combined experience of 15-strong application engineering team, MSC identified productivity gains and cost-down savings that would shatter the contractually obliged target on just two machine tools at the Sulzer manufacturing site in Leeds.

During his initial and socially distanced site ‘walk-round’, Wiezniak was introduced to the machine shop and staff, where early conversations identified concerns over a new project that involved turning a 4 m long Inconel shaft for a new high-pressure pump product line used in heavy-engineering sectors such as offshore.

Currently turning hundreds of 3 to 4 m long Super Duplex shafts, the introduction of Inconel for a new product line raised concerns for Sulzer. However, with hundreds of shafts turned annually on lathes over 20 years old, Wiezniak had no concerns over the performance of the machines.

“The older machines have construction and rigidity that far outweighs most modern machine tools, so we had the perfect foundation for trialling MSC’s range of tools,” he says. “We selected a couple of premium carbide grades for Inconel machining, achieving marginal gains on the speeds, feeds and overall cycle times. To attain the ‘step change’ we really wanted, we had to look at ceramic tooling.”

With the extensive range of Japanese ceramic cutting tools from specialist NTK recently added to the MSC range, Sulzer adopted a paradigm shift in strategy. For Sulzer, the concern around switching to ceramic tooling was the potential for additional heat and distortion. Wiezniak thus identified the need to change the machine coolant, as well as the slide wipers on the lathe bed from nylon to steel to protect the machine bed from the increased swarf temperatures created by high-speed and feed turning.

“With the machine fully prepared for trials, we worked closely with NTK’s application engineer Glyn Shaw and Sulzer’s machine operator and programmer Jamie Fieldhouse; a genuine team effort.”

Despite the stable machine platform, the new coolant and the slide guarding, the trio of engineers realised that the steady rest on one lathe required relocation from an average distance of 1 m from the cutting tool, to 350 mm, to increase the rigidity and stability for ceramic tooling. Ceramic tooling is inherently more brittle and susceptible to vibration than its carbide counterparts.

An initial batch of five Inconel 625 shafts required machining from a raw 200 mm diameter by 4 m long billet, down to a range of stepped diameters from 100 to 180 mm. After the primary work of preparing the machine and devising the rough machining strategies, the trials began. When rough machining the shafts to just leave +2 mm for semi-finish turning, the best carbide turning results typically yielded a finish machining time of 14 hours and 1 minute. Cutting data included depths of cut from 1 to 3 mm, cutting speeds of 40 to 50 m/min and spindle speeds of 80 to 200 rpm. These times, like all other times recorded by MSC at Sulzer account for cutting time only and do not include the additional reductions in set-ups and tool changes.

Wiezniak says: “Upon the recommendation of Glyn, we selected NTK’s Bidemic series of inserts and, in particular, the JX1 grade with a round RNMG12 insert geometry. This was because the Bidemic range offers better wear and notching resistance compared to whisker ceramic grades that are used widely in the industry.

“The NTK trials started at a cutting speed of 250 m/min, but we found the optimal speed for this job at 370 m/min, a massive increase over the 40 to 50 m/min we could achieve with carbide,” he continues. “We also increased the spindle speed from 80 to 200 rpm to over 740 to 1000 rpm, depending upon the diameter being turned.

“Cutting with an average depth of 1.5 to 2 mm, we reduced the rough machining time on the five Inconel 625 shafts from 14 hours, to just 2 hours and 4 minutes per shaft. This yielded a material removal rate (MMR) of 222 cm³/min, up from the previous rate of 30 cm³/min. An unexpected benefit was the improved concentricity after releasing the steady rest. With carbide tools, the rollers were showing a run-out of up to ±1 mm, yet with the ceramic inserts, which only increased workpiece temperature by 9°C during machining, the runout was consistently between ±0.15 to 0.20 mm.”

Aside from a nominal annual tooling cost increase of less than £1000, the six-figure financial savings justify the tool cost increase.

“From discussions with Sulzer, they have already identified more than 170 forward orders for the next 12 months for this particular pump,” says Wiezniak. “Based on our CAM and cutting-tool data, we project that we will reduce annual machining costs by 85%, reduce machining times by 85% and reduce the cost per part by 8%. To qualify this, total cutting hours will fall from 2380 per annum to less than 350, and this doesn’t include set-up and tool change reductions. This will yield a significant six-figure financial saving for Sulzer on the production of forward order Inconel 625 shafts and the respective pumps.”

With the groundwork and trials already successfully implemented on the Inconel parts, the cutting data has also been adapted for Sulzer’s large-bed turning centre that presently has more than 100 Super Duplex shafts scheduled for production.

“Although Super Duplex has a somewhat different and softer composition than Inconel, it is still an extremely difficult material to machine,” says Wiezniak. “We have already started work on this and are fully confident that we’ll replicate the ‘seven times’ overall cycle time reduction from the Inconel parts, doubling our already fantastic results.”

Indeed, MSC has already identified further and potentially equally impressive savings on the same shafts on a third machine. With the rough-turned shafts finished to +0.3 to +0.5 mm, the final process of grinding takes place on an 8-tonne Churchill BX cylindrical grinding centre.

Explains Wiezniak: “While we are optimising the turning process to minimise stock for finish grinding, we have identified potentially huge savings when grinding the Inconel shafts. By introducing new grinding wheel technology with the help of Kim Dean from Tyrolit, we can double the depth of cut from the existing 0.05 mm, to 0.1 mm, effectively halving the 36-hour cycle time. But taking this even further, we’ve also identified cycle-time savings from slashing non-grinding times with the introduction of a secondary wheel dressing unit to reduce wheel traversing distances and dressing times.”

For further information
www.mscdirect.co.uk