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Tool Wear and Failure: Causes and Solutions

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wilsontool.com Punching | Bending | Stamping | News | Media Center April 2013 Tool Wear and Failure: Causes and Solutions Are you seeing excessive or inconsistent tool wear within your stamping die? If so, you know how this can affect the quality of your desired products and slow down your operation. Nobody can afford downtime, especially for reasons that can easily be improved. Tool wear is inevitable, but you should expect to see a long and consistent tool life first. How long each tool lasts depends on many factors including the application and material type and thickness, but if you believe that you are seeing tool wear and/or failure too soon, we have created a list of common occurrences and solutions seen across the stamping industry: Common Issue - Definition Possible Causes Solution Incorrect die clearance Increase die clearance Galling: according to material type and Material fragments build on punch thickness being punched tip (generated from high heat and/or little lubrication) Straight punch tip (no back taper) Add or increase back taper on punch tip Punch will become more difficult to strip from material and will lead to Punch tip grind lines perpendicular Add straight-line grind to premature tool failure to punching direction punch tip Inadequate punch material and/or Try an alternate tool steel coating and/or available coating (application specific) Incorrect die clearance Increase die clearance Head breakage: according to material type and Punch failure at the head end of a thickness being punched punch Straight punch tip (no back taper) Add or increase back taper on Due to shock from heavy punching punch tip application or increased required stripping pressure Heavy application Try Impax’s Xtreme Punch (increased head diameter, thickness, and under head radius). Made from Wilson Tool’s Ultima® tool steel for increased strength and durability Brittle punch head Ensure punch heads are drawn back in hardness to decrease brittleness and increase shock absorption High compressive load Add shear to punch tip to decrease required tonnage Small punch body size Increase body and head diameters for added strength Incorrect die clearance Increase die clearance Tip breakage: according to material type and Punch failure at the tip end of a thickness being punched punch. Tip diameter too small relative to Punch tip diameter should not Due to inadequate punch and/or material type and thickness being exceed a 1:1 ratio compared to tool design. punched the material thickness being punched (for mild steel) Long point length Shorten point length or add step to punch for added strength Excessive punch tip wear due to Add punch guide to die design worn/loose punch/die alignment or add pilots to ensure proper punch/die alignment Incorrect tool steel selected Utilize alternate high speed or powdered metal steel to improve tool life Click here to download a PDF of the Tool Wear and Failure Solutions chart. For specific recommendations, please call the Impax Tooling Solutions engineering team at 800-944-4671. CUSTOMER PROFILE: ARIENS COMPANY Shorter lead times, better tooling improve productivity for Ariens Company. Ariens® Company in Brillion, Wis. developed the first American-made rotary tiller in 1933. Today, Ariens is a leading manufacturer of outdoor power equipment for consumer and professional use, including such well- known brands as Ariens Sno-Thro® snow blowers and Ariens lawn and garden products for consumers, and You have a question about tooling and don't Gravely® zero-turn mowers for commercial use. have time to navigate your way through automated systems. You need to speak to a Ariens employs more than 1,500 people worldwide, live person who can get you the answers you including a dynamic tool and die department that need. employs more than 25 tool and die makers with nearly 600 years of cumulative experience. Wilson Tool has the largest international team of technical support representatives The company does a lot of stamping and operates some serving the sheet metal industry ready and of the largest stamping presses (up to 2,000 ton waiting to take your call. Now is the time capacity) in the Midwest. for real answers to your tooling questions. For decades, Ariens was loyal to a single tooling provider for its stamping operations, until about 12 years ago when delivery issues became too common to ignore. “The Ariens Company switched to Wilson Tool’s Impax® Tooling Solutions brand in our stamping operations 12 years ago, after using a competitor’s line of punches for decades,” said Jerry Schuh, tooling manager for Ariens. “We are extremely pleased with the results we have seen in our stamping operations, as the durability of the Impax line has proven to be superior to their competitors.” According to Schuh, who has been the tooling manager for Ariens for the past 15 years, the prices of Wilson HP Accu-Lock Retainers from Wilson Tool Tool’s Impax Tooling Solutions brand were competitive and the delivery has been excellent. “Despite the fact that I’m probably 250 miles away, if I order a standard punch early enough in the day, I’ll have the punch in-hand in two days at the max without Faces of Wilson Tool having to request any special rushes,” said Schuh. The quality of the tooling is also an important Dean Wold consideration. Higher quality tooling reduces the Lead Supervisor, Impax® Tooling Solutions frequency and duration of downtime for either sharpening or replacing punches. “Because of the quality of Wilson Tool’s tooling and coatings, we’ve seen our tool life between sharpening increase by about 300 percent,” said Schuh. “It’s been incredible. We’ve been able to make a lot more hits before having to sharpen tools. And that’s a big deal when our assembly line downtime costs about $100,000 an hour.” Impax Tooling Solutions provides Ariens with a wide range of standard punch products as well as custom specials when the company’s engineers come up with unusual shapes. Years at Wilson Tool: 8-1/2 Although Ariens could produce these special shapes in- What is your favorite aspect of your job? house with wire EDM, it has proven more cost effective Developing new and more efficient to order specials from Impax Tooling Solutions. manufacturing methods and problem solving with the operators on the floor. “They make it very easy. All we do is send them a CAD model and within 24 hours we’ll get a very accurate What do you enjoy doing in your free time? quote on what it will take to produce that special,” said Schuh. “They do a nice job turning them around Spending time outdoors, mostly fishing and quickly and the punch we get is stronger than anything spending time with my four grandchildren. we could make here.” What is something that people would be From standard shapes to custom specials, the Impax surprised to learn about you? Tooling Solutions division of Wilson Tool delivers I have four grandchildren. greater durability and shorter lead times to help Ariens If you had to eat only one food item for Company be more productive. the rest of your life, what would it be? “The customer service is also excellent. The staff at Fish. the Impax sales desk has proven to be remarkably Where is the most interesting place you helpful and extremely resourceful in their dealings with have been? Why? Ariens,” said Schuh. “Wilson Tool has been a very good Rosario’s Resort on Orcas Island in the Puget partner for us.” Sound near Seattle, Washington, because it was built by a man named Robert Moran in the mid 1800’s who was a machinist by trade Wilson Tool Launches Portuguese- in New York. He then made his way to Language Website Seattle, Washington (population 1,500 in 1875) with $150 to his name. Through various jobs he met a man that would eventually land him into owning his own machine shop where he started building and repairing ships. He became mayor of Seattle at one point and then later built Rosario’s Resort named after the Straits of Rosario in the San Juan Islands. The resort is absolutely beautiful – we had a pod of Orca whales three feet from our fishing boat for over 45 minutes. Very interesting. We are happy to announce the availability of a Portuguese-language version of wilsontool.com for our Portuguese-speaking customers. The website offers easy navigation to engaging, meaningful content on tooling solutions and services available locally. The Portuguese site will serve not only our Wilson Tool customers but also customers of Milling Puncionadeiras through one easy-to-use location. To view the Wilson Tool/Milling website, click here. © 2013 Wilson Tool International. All rights reserved. Wilson Tool International 12912 Farnham Avenue, White Bear Lake, MN 55110 - 800-328-9646 .
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