A years-long push to refine processes, strategically invest in automation, develop new business and upskill workers has paid off in increased productivity and profitability, a stellar safety record and outstanding quality metrics. Total manufacturing time (number of days from the start of an order until it is shipped from the plant) is down 19% in the past five years. Productivity as a percentage of sales is up 23% in the past three. Customer complaints are at 1.2 per 1 million inserts. Average machine availability rate was 97.26% in 2021. And the manufacturing rejection rate in the powder and blanks department has decreased by 46% since 2010, resulting in significant cost savings and setting the benchmark in the Sandvik Coromant group.

The can-do spirit is also on display in the blanks department, where that team recently took the initiative to build a vertical wall storage area for a continuous improvement project. It saves precious floor space, prevents operator mistakes by making labels more visible and substantially reduced inventory-on-hand by limiting storage capacity to what can go on the wall.

Empowerment at every level of the organization is evident in Westminster’s robust safety culture, with team members self-reporting hazards (and, when appropriate, immediately fixing them) and over the past five years making substantial progress in reducing safety incidents. A year ago, the plant celebrated 1,000 days of zero lost-time safety incidents. While that streak was recently broken with a slip on a mat, the plant continues to have a respectable OSHA incident rate of 1.23 for 2021. Employees reported 396 hazards last year, 90% of them resolved within 90 days.

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TIR is less than 0.0001″ (0.0025 mm) even after thousands of tool changes, and powRgrip’s rigidity and high mass minimizes harmonics, extending tool life and reducing consumable costs, according to the company. The system has five sizes, resulting in only five machine inserts the operator would ever need to use every holder, and eliminating the need to purchase machine taper mounts.

Visit the round tools shop, a growth area for Westminster, and you’ll see teamwork and flexibility, as seasoned machinists with a cross-section of expertise work smoothly together and share know-how. Sandvik Coromant recently acquired tooling company Precorp about an hour away in Greer, South Carolina. Westminster leadership saw huge value in the Precorp workers’ tooling knowledge and offered all 40 of them relocation to the Westminster plant. Seventeen took the deal, pulling up stakes and moving their families, and now work as a team with the machine operators in the round tooling shop.

There are secure toolholders for a variety of cutting operations, including milling, drilling and tapping. For example, Emuge Corp. (West Boylston, MA) offers its highly rigid FPC Mill/Drill Chuck with three tons of traction force to hold a tool securely. This is the world’s only chuck with a 1:16 wormgear, according to Emuge. The collet-cone assembly absorbs virtually all vibration, for maximum vibration dampening. With a 3×D tool length, variation in concentricity is less than 3 µm, which extends tool life and substantially improves workpiece surface finishes. All models are balanced to G2.5, 20,000 rpm. In a speed comparison with four competing chuck designs, the FPC chuck enabled the feed rate to be increased by 30% with no loss in performance.

Emuge also produces an extensive line of tapping toolholders. The Softsynchro rigid tap holder, with minimal length compensation, is said to reduce axial force to a fraction of that required in typical tapping applications, improving thread quality and extending tool life by up to 300%. Patented elastomer springs separate the spindle from the tap, absorbing excessive axial forces and providing the tap with a significant boost in tool life and performance. Torque from the spindle is transferred to the tap via ball bearings in precision-ground grooves, promoting precision micro-correction of lead errors in a rigid tapping cycle. The modular system is adaptable to any application requiring a length adjustment screw and interchangeability for different size taps.

Lindsey, who has been at the plant for 29 years, starting as a grinder, has transformed into a self-made data analytics expert (partly through a slew of YouTube videos) and built a system of automated daily push reports that go to supervisors, managers and upper management every morning. He has also built individual departmental reports and created an app to easily share data on the shop floor via phones and tablets.

The Tendo holder contains an internal clamping piston that compresses hydraulic fluid into the oil chamber. The piston is manually actuated by an external clamping screw turned to a dead stop by an Allen key. A flexible sleeve immediately expands evenly against the tool shank, first centering the tool, then powerfully gripping it on the full surface. A length-setting screw can be actuated radially or axially for tool presetting.

Hydraulic expansion toolholders were developed by Schunk more than 35 years ago and have been continually improved to keep pace with advancements in machine technology and carbide tooling, Krolak said. The Tendo line features a high concentric clamping force, excellent vibration dampening and runout of less than 3 µm @ 2.5×D. All commercially available tools, with Weldon, Whistle notch or cylindrical shanks, can be clamped. Micron-accurate tool changes can be made in seconds.

The aerospace industry in particular has a big stake in secure toolholding, notes Jack Burley, vice president, sales and engineering for BIG Kaiser Precision Tooling Inc. (Hoffman Estates, IL). “A number of critical components are made from titanium, which is expensive and difficult to machine. If a cutting tool slips or pulls out, the results are extremely costly, in terms of both downtime and material loss,” Burley said.

Shrink-fit is based on the thermal expansion and contraction of metal, and uses an induction heating unit for assembly. The bore of the holder is initially slightly smaller than the outside diameter of the tool shank. When heated, the holder expands sufficiently to allow tool insertion. After cooling, contraction of the holder grips the cutting tool with up to 10,000 lb (4536 kg) of force. Tools can be changed in seconds, and operator training is minimal. As noted above, the Safe-Lock feature can be incorporated into Haimer shrink-fit toolholders.

Sandvik Coromant’s Westminster plant, which came to the company during its acquisition of cutting-tools maker Valenite in 2002, primarily manufactures cemented carbide inserts—over 2,300 types—for aerospace, automotive and oil and gas tooling. In addition, Westminster produces over 50 different grades of ready-to-press (RTP) powder and customized round tools for industry and refurbishes those round tools for its customers, many of them big names in industry. It has a competitive advantage by being the only plant in the Sandvik Coromant family that produces inserts, round tools and the materials used to manufacture them.

Toolholder manufacturers have responded with a variety of rigid, highly secure systems offering anti-pullout protection. These include shrink-fit, hydraulic expansion and locking toolholders. Each features high gripping torque (clamping force) for a tight friction fit on the tool shank. Many offer proprietary locking mechanisms that can guarantee up to 100% tool retention.

Engineers at Rego-Fix agree that even with the highest clamping forces available, there are applications that require additional cutter retention measures. At IMTS 2012, Rego-Fix introduced the secuRgrip anti-pullout system, available for powRgrip, ER collet holders and milling chucks. A small, profiled steel locking key insert is installed in the ground flat of standard Weldon-shank cutting tools, locking the tool to the collet. A threaded friction bearing cap secures the collet in the holder and provides increased clamping force to prevent the collet from spinning.

An exclusive Key Grip locking mechanism provides anti-pullout protection. It is placed into the Weldon flat of the end mill shank, which is then inserted into one of the three Key Grip grooves inside the chuck. A spring functions to remove the gap between the Key Grip and the wall of the groove. Tightening a clamping nut secures the Key Grip in place, achieving dual contact between the nut and chuck body for rigidity close to that of an integral cutter.

One of BIG Kaiser’s newest products, the Mega Perfect Grip milling chuck, is designed specifically to prevent cutter failure. The high-accuracy milling chuck has fully concentric clamping and runout of less than 0.0004″ (0.0102 mm) @ 4×D. It accepts standard Weldon flat end mills and requires no special grinding of the milling cutter.

”After more than four years, there have been no documented cases of a tool pullout with a secuRgrip holder,” said Chris Herdman, technical field support engineer for Rego-Fix. “The only mode of failure is that of the cutting tool itself.” Unlike other systems, secuRgrip does not require purchase of specially modified end mills, but rather can accept standard 0.5–1″ (12.7–25.4-mm) carbide or HSS end mills. The system maintains 0.0001″ runout and allows users to preset tool heights.

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Key to the increase in productivity is cross-training workers on new jobs and new machines to alleviate bottlenecks. Worker flexibility has not only increased engagement but helped keep production on track during COVID labor shortages. Workers, many with long tenure at the plant, talk about being part of a family and like that they are challenged and respected by their bosses.

Haimer is best known for its extensive line of shrink-fit toolholding. This system is a simple one-piece, highly rigid design with no moving or wearable parts. Benefits include runout accuracy up to 0.00012″ (0.00305 mm), superior repeatability, minimum vibration and chatter and excellent balance, according to the company.

Westminster is in the process of re-evaluating its benefits to see where they can improve; an on-site gym and a part-time on-site nurse practitioner are strengthening wellness initiatives. Management is also tapping into the knowledge of older workers by bringing back retirees to work part-time to train new recruits on machines and processes.

Rego-Fix Tool Corp. (Indianapolis) markets both a friction fit and a tool locking system. The powRgrip series includes holders, collets, and automatic or manual pressing systems. The collet is pressed into the holder with up to 9 tons (8.16 t) of pressure, which Rego-Fix claims to be the highest clamping force in the industry. The compression contacts the nose of the holder and not the taper.

That was yesterday. Today, the productivity needed to be globally competitive requires ever increasing metal-removal rates during operations such as roughing and high-speed slotting. Process reliability is paramount, especially when working with difficult-to-machine materials. Conventional toolholders typically do not cope well with the high axial forces generated by aggressive machining, and cutter pullout can occur.

Shops should be aware that heavy-duty machining is not the only cause of tool pullout, said Ryan Krolak, technical sales specialist for Schunk Inc. (Morrisville, NC): “It can also be the result of toolholders that do not offer concentric clamping,” Krolak said. “This often causes excessive runout, creating an uneven chip load on the cutter and premature tool failure. This shouldn’t have to be said, but it is important to make sure that all the running parameters are within the range of the material and the cutting tool being used.”'

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Westminster’s lean journey began in 2012. The plant is currently focusing on signage and flow throughout the shop, with supervisors and production workers taking charge of the labeling and organizing for their own departments.

For high production tapping, the Speedsynchro tap holder features a programmable integrated transmission of 1:4.412 to optimize thread production on CNC machines with synchronous spindles. Combined with Softsynchro’s minimum length compensation, this allows high cutting speeds at a relatively low synchronous machine tool speed, compensating for synchronization errors during the threading process. Thread production cycle time is reduced by up to 40%, and the lower spindle speed can result in significant savings in energy costs.

For maximum tool security, the Pin-Lock Collet system is available as an option. This feature works with any Weldon shank tool and guarantees pullout protection.

Despite the competition for manufacturing workers, Westminster’s human resources department has had decent success recruiting for the shop floor and even engineering with periodical weekend job fairs they’ve hosted for the past three years. But partnerships with local technical colleges and the public schools are especially important for talent development. Sandvik Coromant Westminster funds college scholarships and has an internship program; its team members are guest presenters in STEM classes and are working with a local elementary school on building a greenhouse. The Westminster team also donates meeting space in its facility for community groups like Girls in Engineering and Manufacturing (GEM) and a STEM summer camp.

Boatloads of initiative and a well-thought-out and executed vision have brought rewards—and profits— for this hardworking team in Westminster.

In a particularly green, winding section of South Carolina sits a city called Westminster that is also a particularly thriving manufacturing center. Boeing, BMW, Caterpillar and BorgWarner have plants in the vicinity, and the competition for workers is fierce. Global metal-cutting tooling manufacturer Sandvik Coromant has a plant here, too, a 328,000-square-foot facility that over the past decade has steadily established itself as a real workhorse. The plant’s performance, and the people who drive it, distinguish Sandvik Westminster as a 2022 IndustryWeek Best Plants Winner.

Drew Strauchen, vice president, marketing and business development, Haimer USA LLC (Villa Park, IL), cautioned against total reliance on the ability of friction-fit holders to provide maximum tool security. “High gripping torque by itself does not equal guaranteed pullout protection,” he said. “The incredible cutting forces generated by faster machine spindles and more aggressive toolpath strategies [like full radial engagement trochoidal milling] have exposed the limitations of even the best friction-fit clamping systems.”

Krolak agreed that machining aerospace parts is particularly challenging. “Aircraft manufacturers have many applications with materials costing thousands of dollars and individual part cycle times exceeding 12 hours,” he said. “With this much invested in each machined component, tool failure is absolutely not an option.” To meet this need, Schunk recently introduced the Tendo Aviation toolholder for applications that require a secure tool that will not pull out.

To hear more from Sandvik Coromant and other IW Best Plants winners, attend the Manufacturing & Technology Show from Oct. 18-20 in Cleveland. All four winner's of this year's awards will participate in a panel discussion on Oct. 19 to discuss how they approach continuous improvement and strive toward manufacturing excellence.

Several years ago, Haimer developed and patented an anti-pullout system, Safe-Lock, as an optional feature on its shrink-fit holders and power collet chucks. Safe-Lock employs special drive keys in the holder and mating grooves in the tool shank, ensuring positive locking in place of the cutter and preventing spinning and pullout. Unlike Weldon flats, the mating ground grooves are perfectly symmetrical, thus eliminating issues associated with unbalance and uneven side loads. The system also provides users with the ability to adjust the axial position of the cutting tool in the holder. With 14 of the largest round tool companies as official licensed partners, tools from any number of global suppliers are readily available.

In addition to the characteristics inherent the hydraulic expansion design, the Aviation toolholder employs a locking mechanism. A cutting tool with a standard Weldon shank is inserted into a special sleeve with a ball lock. The tool/sleeve assembly is then locked into place via set screws in the base of the toolholder. Finally, the holder is hydraulically actuated. As with other Tendo models, this process can be accomplished in seconds.

For many generations, machining was a largely manual process with relatively slow speeds and shallow cutting depths. The most common toolholders were Weldon/sidelock chucks and ER collets, and, under these comparatively benign machining conditions, cutting tool slippage or pullout was not a serious issue.

As machining speeds increase and more difficult-to-machines alloys are introduced, machine shops need to continually re-evaluate their toolholding options. While highly secure toolholders typically cost more than their standard counterparts, the payback—in terms of the ability to machine at higher speeds and fewer scrapped parts and tools—can be substantial.