Mills CNC has recently supplied three Doosan machines to Mellish Engineering Services, a private, family-owned manufacturer of performance-critical, high-integrity and fully-traceable fasteners and hot-forged bolts used extensively, but not exclusively, in the oil and gas sector. The machines, a Mynx 6500/50 large-capacity vertical machining centre, a Puma 2600SY Mk II multi-tasking lathe and a DNM 4000 vertical machining centre were installed at the company’s 26,000 square foot facility in Aldridge towards the end of 2018.

Both standard and non-standard fastener components are being produced by the machines, including bolts, pins, clamps, studs, nuts and washers. These parts are all made from hard and difficult-to-machine materials, such as Duplex and Super Duplex stainless steels, carbon steel, titanium, Inconel and Monel, and are machined to tight dimensional tolerances and high-quality surface finishes. They are machined in small batches right through to larger volumes to suit individual customer requirements.
Mellish-manufactured fastener systems and solutions are in high demand. This demand has been fuelled, in no small part, by the company achieving API (American Petroleum Institute) certification back in 2017.
Explains Mark Rattenberry, Mellish’s managing director: “The global oil and gas industry has always been volatile, and oil price fluctuations are nothing new. However, the spectacular and rapid fall in oil prices, from a peak of $115 per barrel in June 2014 to under $35 at the end of February 2016, had a serious knock-on effect on our business, resulting in reduced sales revenues and an unwelcome squeeze on company profitability.”
As it would later transpire, 2014 proved to be a ‘watershed’ year for Mellish because, instead of battening down the hatches, cutting overheads and riding out the downturn, the company made the strategic decision to plan ahead and invest in its future.
“We took a long-term view and looked at ways to increase our share in a relatively flat, and sometimes declining market,” says Rattenberry. “A key decision we made was to gain API certification which, we believed, would not only differentiate us from our competitors but also, in the highly-regulated oil and gas sector where environmental and health and safety (EHS) concerns are paramount, position us as an approved quality supplier.”
In 2017 Mellish achieved its ambitions, gaining API Q1, API 20E and API 20F certification. Mellish is one of only a handful of companies across Europe to have achieved these standards and, as a consequence, is able to use the official API monogram on its machined products.
“API accreditation is the gold standard,” says Rattenberry. “It is an internationally recognised and accepted kite mark that has had a positive impact on sales”

Since 2017, Mellish has experienced a marked increase in the number of companies making contact, enquiring about the company’s solutions and, ultimately, placing orders. To meet the growing demand for its fastener systems and solutions, Mellish, as part of its company-wide continuous improvement programme, makes regular investment in its people, plant, equipment, processes and systems.
“We are always looking at ways to increase productivity and improve performance, and regularly audit and review our manufacturing processes to see how and where they can be improved,” explains Rattenberry. “Our future depends on us maintaining quality standards, meeting customer lead times and controlling costs. To help, we invest in the latest machine tool technologies.”
The recent acquisition of the three Doosan machines is a case in point and is evidence of Mellish’s continuous improvement programme in action.
The Mynx 6500/50 is a rigid, large-capacity, box guideway vertical machining centre with a large working envelope (1270 x 670 x 625 mm), a large work table (1400 x 670 mm) and a high torque BT50 spindle (15 kW/6000 rpm).
Doosan’s Mynx 6500/50 was purchased following the completion of a successful cutting trial undertaken at Mills CNC’s Technology Campus facility. The trial was intended to demonstrate the Mynx 6500/50’s cutting capabilities and its ability to reduce part cycle times when machining titanium tie-rod components.
“Our Mynx 6500/50 is a rigidly-built and constructed machine that is ideal for heavy-duty machining operations, and for machining the hard materials we use to manufacture our fasteners,” says Rattenberry. “In the machining trial and the subsequent machining process developed by Mills, the part cycle times for machining each titanium component was reduced by 15 minutes. This improvement in productivity, combined with the machine’s large working envelope, which we knew we could exploit to machine multiple parts in a single set-up, were the principal reasons why we purchased the machine.”
Since being installed, Mellish has its focused efforts on refining and optimising the machining process, and has invested in a state-of-the-art manual twin-pallet change system that is positioned in front of the machine, enabling virtually continuous production with minimal operator intervention.

The 10” chuck/76 mm bar diameter Puma 2600SY Mk II is a multi-tasking lathe with a Y axis, sub-spindle and driven tools. Doosan’s Puma 2600SY MK II, with its integrated mill-drill capabilities, enables Mellish to machine small turned parts, like studs and nuts, to completion, in a single set-up. The machine was supplied with a bar feeder to ensure continuous production.
Says Rattenberry: “The Puma 2600SY Mk II is a high-productivity lathe that has helped us reduce part cycle times, improve part accuracies (as components no longer need to be transferred between machines), and help avoid production bottlenecks.”
The DNM 4000 is a fast (48 m/min rapids) vertical machining centre equipped with a direct-drive spindle (18.5 kW/12,000 rpm) and a 20-position ATC. This machine was supplied with a fourth-axis unit to increase its flexibility and productivity potential. The DNM 4000 is being used to machine a family of small fastener parts.
“Despite its compact footprint, the DNM 4000 certainly packs a punch and we have been impressed with its cutting capabilities and performance,” states Rattenberry. “To improve the productivity of the machine we have designed special purpose fixturing that enables multiple parts to be machined in a single set-up.”
Productivity and operational efficiency are critical to Mellish’s future growth and prosperity.
The investment in Doosan machine tools from Mills CNC, combined with the company’s determination to “sweat its assets” and continuously look at ways to optimise its machining processes, means that Mellish is able to meet the surge in demand for its fastener products and solutions.
Concludes Rattenberry: “Our decision to go for API accreditation has been vindicated and business is booming. We are focused on maintaining our market-leader status in the oil and gas industry, and investments such as those made in Doosan machine tools from Mills CNC will enable us to do this.”
For further information www.millscnc.co.uk

An engineering subcontractor recently moved all of its CAM programming to Edgecam after Seco Tooling provided the company with support solutions to specific issues on complex components.

I&G Precision Engineering had used Edgecam to drive an Emco lathe operated by the firm’s hands-on managing director Andrew Evans since investing in CNC machinery in 1992. However, as the company expanded with further machine tools and more shop-floor staff, other CAM packages were introduced.
“Originally, we used Edgecam for both milling and turning on those new machines, but when I came off the tools we decided to try other systems, and it was eventually only used on the lathe,” he says.
Operating out of 11,000 sq ft premises in Ystalyfera, Swansea, with 11 employees, the company largely manufactures parts from stainless and tool steels, as well as aluminium, for aerospace, food, beverage, medical and defence customers, along with the Royal Mint. I&G makes a number of components for aerospace ground-support systems such as jigs and fixtures that are used to remove engines and wing parts. The company also produces everything from bakery equipment, including rollers for production machines and castings for dough-rollers, through to electronics housings for defence customers. In addition, the company has received commendations from the NHS for its work in devising breathing apparatus that help new-born babies inhale xenon gas as part of medical treatment.
Andrew’s son, Mike, who is engineering director and workshop manager, says that I&G works closely with Seco Tools, which recently provided the firm with tooling and programming support to improve the production process on a specific job.
“We saw immediate benefits, as the job used to take us around three hours – including two hours for just one operation – but using Edgecam the full process was completed in an hour,” says Mike Evans. “When we looked at how Edgecam machining strategies could improve our cycle times it became a no-brainer that we should go back to it on our range of Haas CNC machine tools, and our new Mazak vertical machining centre.”

All new components now go through Edgecam, and production runs of older parts are all being reprogrammed.
“We’re saving up to 40% on cutting cycles, which has a tremendous impact on the bottom line,” he says. “It improves our margins, making us more profitable and releases additional capacity to take on more work. Edgecam is a vital part of our manufacturing process now. It runs the entire production process.”
Evans says that the software’s milling and turning modules ensure they can ship between 600 and 700 components each month, normally on a three to four week lead time.
“Edgecam is so simple to use,” he states. “The customer sends us a STEP or IGES file, or any other CAD file, which we import into the software and create fixtures and fittings, identify the CNC machine we’ll be using, and the stock. Then we run ‘Feature Finder’ to identify all the features of the parts, and generate tool paths.”
“Machining processes are considerably more stable now than under our previous CADCAM package,” continues Evans. “With our old software, when the cutter was coming into a corner you could see the machine loads spiking, which we don’t get with Edgecam. We can run programs overnight, rein the step-overs back and know the tooling will last for the entire production run.”
He describes Edgecam’s ‘Waveform Roughing’ capability as “massive” for the company’s growth plans, in terms of driving down cycle times and increasing capacity, enabling I&G to take on additional work.
“We do a lot of 3D milling on features such as pockets, and we previously undertook the roughing cycles in the traditional way, often just stepping down 1 mm at a time. However, Edgecam allows us to step down up to 10 or 15 mm at a time. Then, as we pocket out to those depths, we can profile back and come out of the pockets, so it saves considerable time.
“At first, when those programs were coming in from Seco Tools, we were concerned that the increased feeds and speeds would break the cutters,” he adds. “But then we saw how well they worked, and it now gives us the opportunity to push the machines to their limits.”

He cites a project where Waveform slashed the roughing cycle from 30 to 10 minutes, and helped reduce the overall machining time by half.
“We manufacture a particular component for the atomising industry, which is used to turn metal into a powder for hard surfacing materials. Traditionally it was a turning job, but Waveform means we can now mill the grooves. This was a huge revelation, and made us think of doing jobs in a completely different way.”
The company is planning more investment in the coming 12 months, including the purchase of Edgecam Inspect, which creates measurement cycles on machine tools.
“This means we’ll be able to inspect every part on the machine if necessary, after each operation, and provide a customer report,” says Evans. I&G is also considering a five-axis machine, and possibly a CMM from Hexagon.
Concluding, Evans says he introduces Edgecam to the company’s apprentices immediately.
“We’ve currently got three apprentices at various stages, and they’ve all taken to Edgecam like a duck to water. The skill set is changing; a lot of the old traditional craftsmen’s skills are dying out, and engineers need to embrace computer-led skills to produce the components properly. Edgecam helps engineers deliver what’s needed by offering several ways of achieving the same result.”
For further information www.edgecam.com

Nestling in the Dorset countryside on the edge of Bridport, sheet metal subcontractor Ackerman Engineering’s freehold 1500 sq m factory was purpose-built in 2006 by current managing director, Graham Ackerman, great-grandson of the company’s founder, William, who started the enterprise in 1885. Indeed, 2006 was a seminal year that saw the purchase of a Bystronic BySpeed 4.4 kW CO2 laser-cutting machine, another press brake from the same supplier and a generation facility for nitrogen.

Nitrogen is the assist gas of choice when laser cutting as it produces a non-oxidised edge for painting without the need for fettling. In addition, nitrogen allows cutting speeds up to three times faster in thin to mid-range gauges.
CO2 laser technology, which had been used by the company since 2001, was phased out in August 2018 when the 4.4 kW machine was part-exchanged for a ByStar Fiber 8 kW fibre laser-cutting centre, which joined a 3 kW BySprint Fiber installed four years earlier. Both are of 3 m x 1.5 m sheet capacity. At the same time, an Xpert 150-tonne, 3.1 m press brake was added to the six Bystronic models already on-site, one of which dates back to 2001 and is badged Edwards Pearson, which the Swiss manufacturer acquired in 2002.
The advantage of profiling and bending components on the same make of equipment is that Bystronic’s offline Bysoft 7 software modules, ‘Laser’ and ‘Bend’, work together to produce precise 3D sheet-metal parts. Graham Ackerman says that drawing tolerances are almost incidental, as they are routinely held due to the accuracy of machining. Inspection is scarcely needed, as quality is virtually guaranteed once a job is in production. Any mistakes are almost always down to human error, so most of inspection effort is at the CADCAM stage.
A customer’s drawing or model, which usually arrives in DXF, DWG, IGES or STEP format, is interrogated in the subcontractor’s CAD department to ensure the component’s manufacturability. The file is then exported as a flat blank to the Bysoft CAM environment, where the programs for fibre-laser profiling and bending are generated automatically.
Ackerman says: “Fibre-laser cutting is massively faster than CO2. When we installed the 3 kW BySprint Fiber alongside the 4.4 kW BySpeed CO2, the former was so productive that we could have sold the other machine and still hit production targets. The only reason we didn’t was to retain back-up capacity for servicing or unusual peaks in order to guarantee customer deliveries.”
He adds that the Bridport factory mainly processes aluminium, stainless steel and mild steel sheet from 0.7 to 8 mm thick, with a lot of material in the 1.2 to 2 mm range for the manufacture of electrical cabinets. When cutting these gauges, the 3 kW fibre machine is typically two to three times faster than CO2. However, when the 8 kW fibre laser was installed, a further increase in throughput was seen, as processing times are less than half those using the 3 kW fibre source.
Additionally, CO2 machines require a 15-minute warm-up in the morning and a similar time to close down at the end of the day, whereas these unproductive periods are avoided with fibre-laser cutting. Another benefit of the technology is its low running costs. No laser resonator gas is needed, while an even greater saving derives from reduced electricity use.

Ackerman notes that the firm’s larger fibre source draws less than half the power of the previous CO2 machine, yet delivers nearly twice the power to the point of cutting. The wasted energy previously had to go somewhere, which was into the factory in the form of heat, so the fibre-only working environment was more pleasant during the summer months.
Appraising his company’s use of fibre-laser cutting, Ackerman made a couple of interesting observations. One was that the 8 kW machine is so fast that the expected increase in nitrogen usage did not materialise due to the short cycle times, so it has not been necessary to increase the size of the gas generation plant.
Another comment was that on some delicate parts, which are frequent bearing in mind that the subcontractor operates at the high quality end of the market, the 8 kW laser beam can be
too strong for cutting 0.8 or 1.2 mm material, a problem that is easily overcome by turning down the power of the source.
To maximise productivity, however, the lower power fibre machine is designated to cut thinner gauges, while the 8 kW laser cutting centre is kept on full power for processing thicker materials.
As to his company’s move away from other makes of laser-profiling machines to standardise on Bystronic equipment, Ackerman says: “Our business recognised more than a decade ago these Swiss-built machines are among the best in the world and highly productive, both in terms of processing speed and maximising uptime. We especially like the speed of changeover to the next job, which is important to us as we produce small batches of high added-value work, typically within the range 5- to 50-off.”
It is due to these relatively low batch sizes that Ackerman Engineering has restricted its automation equipment to simple ByLoaders for feeding the fibre-laser machines with material. The step up to a ByTrans automated sheet loading/unloading arrangement would have not lent itself to such small runs. In any case, it would have necessitated tagging components within the sheet, then shaking them out and de-pipping them, which is not conducive to the premium-quality work for which the subcontractor is known.
Modern press braking technology has been a similar boon to the firm’s business. Ackerman is particularly impressed with the latest Bystronic Xpert 150, for which he has bought a comprehensive suite of the manufacturer’s RF-A segmented tooling. He says it is twice as fast to set up compared with older style tooling, as the punch and die segments are automatically centred when loaded from the front and hydraulically clamped.

Moreover, the system is fully compatible with the Bystronic bending database in the machine control, and it is practically impossible to insert an incorrect tool due to laser beam recognition of its profile. Part quality is improved, especially when bending long components, as there are no witness marks where the tool segments meet, and there is no need to resort to shimming.
When Ackerman joined the family firm in 1979 at the age of 17, the only other employees were his father, David, together with three or four other staff. From the early 1970s using a treadle guillotine, self-made power press tools and an Edwards box and pan folder, David started producing light sheet-metal fabrications. The company had nearly reached its century but had not realised much in the way of progress. Ackerman Engineering had, however, reinvented itself a number of times, from its beginnings in watch and clock manufacture, to automation of Bridport’s netting looms in the 1950s and 1960s.
Ackerman concludes:
“Once sheet metalworking became our activity of choice, the foundations of sustained growth ensued. Today we have 34 staff working in Bridport, including a fifth generation Ackerman, my son Edward.
“By the time he takes over the business, with our policy of constant reinvestment, we will have grown further and there is plenty of room for expansion on our current site. The purchase of highly productive production plant like the Bystronic machines will be key to our continued success.”
For further information www.bystronic.co.uk

A mould maker serving the automotive industry says WorkNC CAM software gives it a distinct advantage, setting the company apart from its competitors with superior lead-times, quality and expertise. And, as a Beta tester for WorkNC, the company found that a new item of functionality, introduced in the latest release – 2019 R1 – slashed its finish-machining
times by more than half on certain parts.

Operating from three sites in France and one each in Turkey and Slovakia, Julien SA manufactures moulds for interior linings, boot compartment trim and roof linings, along with parts for sound-proofing, foamed components, and aluminium and textile thermal barriers. The company mainly produces single-order parts, or two-to-three small series moulds for foam components.
Based at the 10,000 sq m head office in Le Creusot, France, programming manager Sergio Couto is responsible for preparing production and implementing the product manufacturing process. His department takes the lead on a range of aspects such as technical issues, monitoring and quality control for tooling production.
Although Julien SA makes a small number of moulds for the aerospace industry, most of its customers are major automotive groups that need tight turnaround times. Using WorkNC’s CAD and CAM capabilities, Couto says practically nothing is impossible from a technical point of view.
The software is installed on seven computers on the company’s network, and drives three five-axis machine tools (Breton, Durango and Rambaudi), and four 3+2 machines (Goglio, FPT, Anayak and Soraluce). Explaining how WorkNC is an integral and vital part of its production operation, Couto says the process begins after the programming team receives an assessment from the engineering office with the purchase order: “Firstly, we analyse the CATIA file of the part to be produced, allowing us to isolate items which need to be precise, and to determine what’s feasible.
“With the aid of WorkNC’s CATIA interface we can re-establish the CATIA construction tree, which is crucial, as that data is of paramount importance to our business,” he adds. “WorkNC is one of the rare applications which allows this.”

The company then turns its attention to the number of parts that must be produced, and sets about creating the models in WORKNC, adding offset allowances and any other details required for accurate machining.
“The next step is to prepare the production phase and run tool-path calculations,” says Couto. “We establish machining schedules and adapt WorkNC tool paths to the specific machine being used.”
However, he adds that occasionally the company does not know which machines will be available, meaning generic tool paths must be generated. “This highlights the importance of ‘Machining Contexts’ in WorkNC, because we often have to switch to another machine at the last minute,” says Couto.
The final phase is in the workshop, where WorkNC’s simulation function validates the process before the machines start cutting metal. Here, he says WorkNC’s programming allows the company to undertake lights-out machining: “It means the workshop operates 24/7. From midday on Friday and over the weekend, it is fully autonomous, with automatic tool changing and head rotation. We couldn’t do that without WorkNC.”
As a beta tester for the software, Julien SA trialled a new finishing strategy which allows users to break free from previous constraints caused by tool shapes, and it has slashed machining times by more than half. As a result of the trials, WorkNC 2019 R1 adds the Z-level pattern to the ‘Advanced Toolform’ technology, allowing for tool shapes like barrel, oval and parabolic to be calculated over the part surfaces, including negative allowances.
Couto says the results of using the Advanced Toolform strategy with circular-segment cutters, compared with traditional methods, are indisputable, having reduced the company’s finish-machining times from 32 hours to 14.
WorkNC, part of the Production Software business of Hexagon Manufacturing Intelligence, is fully integrated into every machining phase – analysis, comparison, simulation, machining and verification.

Summing up the benefits of using WorkNC, Couto says tool-path calculation times are no longer an issue: “We manufacture some large parts – 2 x 1.5 m – and it’s very rare that calculation times are longer than eight hours for all roughing, finishing, rest material, corner re-machining, and mechanical operations such as drilling and pocket machining. And it’s a user-friendly application that’s so easy to learn, even for employees who’ve never done any programming before.”
The company has also invested in a mobile measuring arm from Hexagon, to make precise measurements at different stages of the manufacturing operation. Julien SA uses the measuring arm to make immediate decisions to either modify or continue the process when a doubt arises, which Couto says guarantees security, saving time. “This all helps with the precision we need to actually manufacture the part, ensuring it’s of high quality, and that it can be cleanly and accurately trimmed, which is particularly important for its final appearance as many of the parts coming out of our moulds are visible to the end user in the vehicles.”
Concluding, he explains why the company first invested in WorkNC in 1994, and how it has developed since then: “In the 90s, mould makers started receiving files from India and China in which radii and planar surfaces didn’t conform to the original part, and it was no longer possible to program with CATIA. Even back then, WorkNC could rapidly generate a tool path, irrespective of a part’s complexity or imperfect surfaces.
“WorkNC has developed in line with the requirements of milling operators, who had previously programmed tool paths directly at the machine tool. We have total confidence in working with it on a daily basis, and it helps us to take issues such as holidays, sickness absences and machine downtime in our stride. It means we can set ourselves apart as a mould maker, ahead of our competitors.”
For further information www.worknc.com

High quantities, extreme quality requirements and keen competition are shaping the production of injection-moulded parts for the automotive industry. To ensure success when performing this delicate balancing act, Gevelsberg, Germany-based Denk Kunststofftechnik relies on Schunk grippers in its self-designed handling systems.

“Around 60% full automation, and the trend is rising rapidly; we are no typical plastic injection moulders,” states Konstantin Spenst, head of automation technology at Denk. “Automation is the only way to output between 500,000 and well over 2 million parts per year, and check them 100%.
“Precision and verifiability are decisive factors for us,” he adds. “The newer the system, the more steps are monitored. Recently we wrote a chain of 800 steps, but only 30 of them were paths. Everything else was just commands of pneumatic components or queries with alarms.”
Around 60% of the range was operator messages such as “end position not reached”, “part lost” or “part not correctly mounted”. What is decisive nowadays is that the user receives as much information as possible, because in the case of a malfunction, the reason must immediately be identified. This factor is particularly thanks to the precise monitoring of grippers, as only in this way can damage to the tools be avoided, along with system downtime.
At Denk, all parts are first monitored to see that they are correctly mounted. Presence monitoring is then deployed immediately before mounting the tool; ultimately checking immediately after removal and finally during storage. This methodology is the only way to prevent parts from being lost in the handling process, causing an expensive tool collision.
The gripping systems that are increasingly being conceived, designed and built independently by Denk since the beginning of 2010 are of double significance. Each system must ensure reliable handling, while at the same time facilitating reliable monitoring of the relevant process steps. Historically, the latter had proved to be a challenge, because not all gripping system components available on the market permanently achieve the required level of precision and process reliability, not even the high-end ones.
“With our gripping systems, precise monitoring is very important, as with 1 mm play in the gripper jaws and a closing stroke of 3 mm, reliable monitoring is not possible,” says Spenst. “It repeatedly transpired with grippers from various manufacturers that sensors delivered unreliable results because the play in the jaw guidance was so large. Over the course of time, we have realised that Schunk grippers can be queried very reliably, as they work very precisely.”
The Schunk MPG-Plus grippers for small components are particularly advantageous in this respect.
“For parallel grippers, not only an end point can be queried, but also a centre point, which can be set very easily,” says Spenst. “If a component gets lost, the end switch is set to zero and reports the loss. When handling metal parts, an inductive sensor usually monitors whether, and at what distance to the sensor, a metal inlay is gripped.”
Besides inductive monitoring, the Schunk MPG-Plus miniature gripper can be monitored by integrated and programmable magnetic switches, by means of which a high degree of flexibility can be attained. Compared with similar modules on the market requiring the same input, the gripper produces a significantly higher output – says Schunk – paving the way for ever smaller and more efficient systems.
The high-performance, individually adapted junction roller guide ensures high load bearing capacity of the entire guidance system, minimal wear and a long life span. Components made of special, high-performance aluminium are used internally. In order for engineers to be as flexible as possible in process and system designing, the module can be screwed through and tightened both on the side, as well as the bottom.
“The grippers must be as light and as small as possible,” stresses Spenst. “If I have a heavy gripper, I have to move slower. This costs cycle time and cycle time is real money.”
On average, the loss of one second of cycle time costs between €2000 and €4000 each year. To keep warehousing as low as possible, Denk uses the miniature gripper primarily in sizes 40 and 64, in order to dock gripping systems on to the tools in a stable manner when loading. For large strokes, the Schunk KGG 80 two-finger parallel gripper is used. This gripper even allows handling of T-nuts with adhered chips. For larger, round components, Denk uses the Schunk PZN-plus centric gripper, which due to patented multi-tooth guidance and manually ground base jaw guidance, combines a high level of precision with low wear.

For Spenst, the standardisation of the gripping system components is elementary: “We want to keep inventory as low as possible to ensure the universality of our systems, and to react flexibly in the event of damage. When we design grippers with Schunk, we know that we will be able to handle 2 million parts a year for seven years, without losing any precision or having to fit new grippers.”
For normal use without overloading the grippers, these cycle rates can definitely be achieved and sometimes even exceeded. The temperatures in the injection moulding machines are generally non-problematic for Schunk grippers. Only in critical applications do the designers at Denk contact the manufacturer and ask about maximum permissible values.
Despite the high level of gripping systems expertise, it is not possible for Denk to manufacture the module components in-house.
“We could certainly build parallel grippers, but they would cost 20 times as much and would still not achieve the level of quality provided by the Schunk modules,” says Spenst.
After the relaunch of the PGN-Plus-P parallel gripper, Schunk has now transferred the features of its flagship product to the three-finger gripper series. The Schunk PZN-Plus-P centric gripper is now equipped with a permanent lubrication unit in the multi-tooth guidance system which, under normal, clean working conditions, ensures lifelong maintenance-free operation.
With short strokes in particular, the continuous lubrication pockets are said to produce a fast and even distribution of lubricant along the entire multi-tooth guidance contour. By enlarging the supporting dimensions between the six load-bearing shoulders of the patented multi-tooth guidance system, higher moments can be accommodated and thus longer fingers can be used. In order to ensure fit accuracy, each individual base jaw is carefully ground (manually) and fitted to the individual housing. Moreover, the large piston drive area helps to maximise gripping force.
For further information www.schunk.com