Article
October 9, 2007
Ridin' the storm out
Editor's Note: This is the third article in a three-part series on Tennessee Stampings LLC. Part I in August explored the company's lean practices. Part II in
September discussed how the company's use of sensors and mistakeproofing led to its growth. Part III examines the company's... Read more...
Article
August 8, 2007
Ridin' the storm out Part I
Editor's Note: This is the first article in a three-part series on Tennessee Stampings LLC. Part I explores the company's lean practices. Part II in the September issue discusses how the company's use of sensors and mistakeproofing led to its growth. Part III, which will appear in the... Read more...
Spanish
July 10, 2007
Actualizando una prensa para un cambio rápido de dados
En la mayoría de las operaciones de estampado se debe reducir los costos, lo cual requiere un aumento en la productividad así como mejora en la calidad de las partes. Un manejo eficiente de los dados y procedimientos rápidos de cambio pueden ayudar.
Beneficios del Cambio Rápido de Dados... Read more...
Article
April 11, 2005
See unitized tooling make a difference
Figure 1 Modular press tooling can be used to punch or notch 2-D flat sheets and 3-D forms. As life cycles get shorter, total program quantities are lower for both end products and components. The hard tooling needed to make those components is amortized over fewer parts—which... Read more...
Article
January 11, 2005
Implementing a stamping sensor program—uphill
Stamper and toolmaker Ultra Tool & Manufacturing, Menomonee Falls, Wis. had been installing basic stamping die protection for 15 years. Whisker sensors, positive stops, and, in some cases, part-out sensors comprised the limited sensor system for dies that ran in automatic mode. However,... Read more...
Article
July 13, 2004
Acoustic emission monitoring for stamping presses
Sheet metal forming companies face constantly increasing demands for higher production speeds from their machinery and more complex parts. At the same time customers demand higher standards of quality and stringent price controls, even as production volumes swell. Figure 1 If a... Read more...
Article
June 8, 2004
Sink-making secrets
Figure 1 Double drawn stainless steel sink Sink photo courtesy of Polarware. Have you ever looked at a deep-drawn double-bowl sink and wondered how it's made? After all, one deep-drawn shell is right next to the other. Where does the metal come from to achieve the height? Figure... Read more...
Article
June 8, 2004
Spraying it right
For coil-fed applications, spray cabinets can be mounted to the feeder to accommodate passline changes. Most stampers understand the need for lubricants, but many apply as little as possible so they don't have to deal with the mess. Others take an opposite approach and flood the tool... Read more...
Article
June 8, 2004
Advanced lubricant technology for high-strength steel
Figure 1 As if the recent rise in steel prices weren't enough, now automotive stamping suppliers are faced with the difficult task of getting high-strength steel (HSS) to form parts with tooling designed for mild steel. In an effort to reduce vehicle weight and improve gas mileage,... Read more...
Article
May 4, 2004
Saving time and reducing waste with quick die change
Material waste, of course, is readily identified and quantified. Waste caused by lost time, however, is more subjective, and quantification often becomes a matter of opinion, which makes it more difficult. In the current business climate, cost reduction and waste elimination are the... Read more...
Article
May 4, 2004
Eliminating slug pulling during piercing operations
Author's Note: Before I get into the meat of this article, I would like to let my readers know how much I appreciate their loyalty to STAMPING Journal® and the Die Science column. STAMPING Journal now is published monthly, and I am delighted to announce that I will be writing the Die... Read more...
Article
April 6, 2004
Stamping tools for UHSS get tougher
The automotive industry wants to develop cars that are lighter, stronger, and less costly to manufacture. One way it can achieve these goals is to construct body panels, suspension components, structural members, and frames using ultrahigh-strength steels (UHSS). Increasing an automotive part's... Read more...
Article
April 6, 2004
Article
March 11, 2004
Venturing Into the World of 3-D Die Design
This question has been plaguing the tool and die industry ever since major advances in technology and software yielded this powerful potential. It is nothing today for central processing units (CPUs) to have gigahertz speeds and gigabyte memories. With prices stable or dropping on... Read more...
Article
February 26, 2004
Tube Hydroforming Design Flexibility—Part V
Combined with the information in Part III of this series that focused on cross-section expansion before hydroforming, this article discusses the most common options used in preparing tube for hydroforming and achieving the designer-intended part. Properly executing bending and cross-section... Read more...
Article
January 13, 2004
Troubleshooting compression bending
Most compression bending problems are one of three types: Flattening or collapsing on the outside of the bend. Crimping or wrinkling on the inside of the bend. Dimpling on the inside of bend. Generally you can prevent these problems by implementing these standard solutions:... Read more...
Article
January 13, 2004
Appliancemaker reduces downtime with stamping press feed system
Most of the parts are stamped out of light-gauge metals. "On the majority of our machines, we're feeding 0.0040 inch and less," said Dan Partin, senior process engineer at Whirlpool. Partin reported that the company had noticed excessive downtime on some of its key presses that were running for... Read more...
Article
January 13, 2004
Rolling bolsters bolster productivity
Shown out of the press, the guided wheels on this 120,000-pound rigid chain rolling bolster are evident on the front face of the bolster. One element of changing dies in stamping presses quickly and efficiently is the use of a rolling bolster. With this equipment, the operator rolls... Read more...
Article
October 9, 2003
Controlling bend angles
Spring-back Analysis All metal has a certain amount of spring-back. Spring-back, also known as elastic recovery, is the tendency for the metal to want to return to its original flat blank shape after being bent. To fully understand why metal springs back, we first must understand that metal,... Read more...
Article
October 9, 2003
Eliminating final trim shearing of hydroformed tube
An alternative to trimming a tube to establish tube length is to form the tube in the preform operation to a geometry that is close to the final product and to seal it during hydroforming with caps that match its formed shape. Generally, a round tube is bent on a rotary draw bender... Read more...
Article
September 25, 2003
The wrinkle-wiper for tube bends
Figure 1 Here's a quick quiz for you to take: What "wipes" the wrinkles from the bend in a tube and is one of the five pieces of tooling in a die set? If you guessed wiper die, you're right. A piece of tooling used to keep the inside bend of a tube from wrinkling, a wiper die... Read more...
Article
August 28, 2003
Die geometry for embossing and stretching
Embossing usually refers to the stretching of metal into a shallow depression. Unlike drawing, embossing entails little or no inward metal flow. Some automobile hoods and parts are made using a stretching operation, while others use a combination of drawing and stretching (see Figure 1 ).... Read more...
Article
August 28, 2003
Roll out the shelving
These units typically are used in conjunction with overhead cranes, roller arms, and powered conveyors located at the press. The operator pushes a button that rolls out a shelf, picks up the dies with an overhead crane, and takes them directly to the press. Rollout shelves can be manual... Read more...
Article
August 28, 2003
Article
August 28, 2003
Minimizing wall thickness variation in seamless tubing
Reducing the amount of variation, or achieving more wall thickness consistency, can be the difference between meeting a customer's requirements or not. It also helps to reduce or even may eliminate the customer's need for subsequent processes such as machining. Seamless tube typically is... Read more...
Article
August 14, 2003
Stamping out bad parts
One option for stamping quality control to help fabricators determine shape, strains, and thinning is full-field optical vision technology. Based on the principles of circle grid analysis and photogrammetry—the science of making precise measurements by recording and analyzing... Read more...
Article
August 14, 2003
Toolmaker tricks
This article focuses on a few tricks of the tooling trade that have been used for years. It is very important for toolmakers, troubleshooters, and technicians to make rational data based decisions regarding permanent corrective action. These tricks are intended solely for data gathering purposes... Read more...
Article
August 14, 2003
Virtual tryout
In this era of global warp speed and virtual reality, calculating the deep draws of progressive dies or the springback of metal is performed by simulation software instead of the earlier trial-and-error method. These software programs essentially replace the artistic methods of diemaking... Read more...
Article
August 14, 2003
What's driving your press?
They no longer are dedicated to running one product for their entire life, and once dedicated lines now perform versatile tasks and provide flexibility from one job to the next. Whether it's for setup of a servo roll feed, an in-die transfer system, or a complex tandem line, flexibility... Read more...
Article
July 24, 2003
Taking the heat, keeping the current
A DaimlerChrysler powertrain control module cover/heat sink assembly needed to be thermally conductive yet electrically isolated. The populated circuit board—one with all components in place—had to be bonded to the heat sink and postcured in a vacuum laminating press. The... Read more...
Article
July 24, 2003
Maximizing a coil fed press
Modern Coil-fed Presses Stamping processes revolve around two basic styles of tooling, transfer and progressive dies. They both require feed-to-length systems but differ in many key areas. Blanking processes could be added but are progressive in nature. Transfer tooling requires material to be... Read more...
Article
May 29, 2003
Reducing Die Changeover Time without Capital Expenditures
Knowing what needs to be done is one thing; providing the cost justification in today's tough economic environment is another major issue. The first priority is to maximize existing resources as much as possible before spending any money. Take all opportunities to resolve productivity... Read more...
Article
April 24, 2003
Tube Hydroforming Design Flexibility—Part III
The last article in this series noted that variable periphery design, or cross-section expansion, often is thought to be the most important aspect of tube hydroforming design flexibility. Expansion in the hydroforming die commonly is assumed to be the most efficient and most effective method,... Read more...
Article
April 24, 2003
Hydraulic forming takes a front seat
While designers took these limitations into account and designed the product to be forgiving at the ends of the channels, several factors over the past decade have caused the company to use roll forming less and less. The Move Toward New Technology The first change to influence the... Read more...
Article
April 24, 2003
Applying and handling die lubricants
Effective application of die lubricants typically is overlooked in many stamping facilities. Many companies try to get by with applying as little lubricant as possible, just so they don't have to deal with the mess. However, metal stampers need to move away from thinking of in-die... Read more...
Article
April 24, 2003
Truckin' along through a stamping plant
The earlier cab models were built in a facility that was converted in 1921 to produce the model S truck line, a truck with a 1.5-ton load capacity and a top speed of 30 MPH. The company determined that it could not competitively launch a new line of vehicles without building a new... Read more...
Article
April 10, 2003
Establishing a die setup recipe for progressive dies
To reduce the number of mistakes, it is important to have a good die setup recipe for each progressive tool. The special setup sheet should contain numerous items in checklist form. Setup Checklist All of the following items are crucial to your die-setup recipe. Although some of these items... Read more...
Article
April 10, 2003
Improving perforating die performance
To perforate the part material, the material must fail. The harder the part material, the greater the forces on the punch and matrix become, resulting in sudden shock, excessive wear, high compressive loading, and fatigue-related failures. During impact and penetration, the cutting edges... Read more...
Article
November 15, 2002
Equipping Your Press With the Right Tonnage Monitor
Tonnage monitoring equipment has been around for several decades. The early models were sometimes finicky, hard to use, and susceptible to outside electrical interference. Today's tonnage monitors are easier to install, simpler to use, and more reliable. Many types are available to meet the... Read more...
Article
October 10, 2002
Tube Hydroforming Design Flexibility—Part II
It's difficult to overemphasize the importance of cross section expansion when you're talking about successful and innovative hydroforming of steel tubing.
Overemphasizing one aspect of the tube hydroforming design process can take attention away from others and result in less than optimal... Read more...
Article
May 16, 2002
Tube Hydroforming Design Flexibility—Part I
Design flexibility is something that all automotive designers want, but too often they lack a thorough understanding of what that means—what aspects of design flexibility apply to a certain part and their effect on cost.
A methodology often is adopted when (or even before) a part... Read more...
Article
December 13, 2001
Punching tips
I used to listen to an eight-track tape of Buffalo Springfield while I ran a kick punch. If you've never seen a kick punch, it basically is a lever-operated C-frame press. You cause the punch tip to lower by pushing a pedal forward with your foot.
I remember running a job on some 16-gauge... Read more...
Article
December 13, 2001
Keeping pace with today's punching requirements
Figure 1 The punch, die, and stripper's function still is to punch holes that are a specific size and shape into sheet metal in a specific location. The quest for accurately punched holes, top-quality piece parts, and long tool life can be a positive experience when you consider your... Read more...
Article
December 13, 2001
Bending tube with an all-electric machine
In the tube bending industry, all-electric, CNC benders are a fairly new development but are gaining ground. They have been commercially available in Europe since 1995 and in the U.S. since 1998. Most manufacturers now either offer all-electric bending machines or are developing them. On... Read more...
Article
November 29, 2001
Preventative maintenance as a way of life
Object When I was invited to serve as a preventive maintenance (PM) coordinator at a Chrysler plant in 1992, a story was circulating that was relevant to not only what we learned at Chrysler, but to any stamping line. According to the story, a line supervisor-technician on a Toyota stamping... Read more...
Article
November 29, 2001
Designing presses and dies with FEA
Figure 1: FEA software produces graphical illustrations of the results of standard stress analysis on every side of a part. Your marketing department has just come up with a new product idea that requires you, the press and tooling manager, to find a new tool and perhaps a new... Read more...
Article
November 29, 2001
Gettin' down with downtime
The pressures of increased competition and the need for stampers to stay competitive affect every aspect of their operations. One of the key ways stampers can create an efficient and cost-effective operation is to reduce downtime on the shop floor. One of the principal causes of downtime... Read more...
Article
November 15, 2001
Article
November 15, 2001
Using hydroforming aluminum components versus steel stampings
As the name implies, hydroforming is a metal forming process that uses water as a forming medium. In the case of tube hydroforming, a tubular workpiece is placed between two mating die halves. The tube is sealed, normally by metal mandrels inserted under pressure in each end of the tube. Water... Read more...
Article
October 25, 2001
Article
October 25, 2001
Comparing single-cut and dimple-free tube mill cutoffs
This article covers the application of single-cut and dimple-free cutoff shear technologies as they are applied to contemporary high-speed tube mills. A single-cut die set is a unit composed of an upper shoe and a lower shoe in which a single severing blade and tube supporting jaws are... Read more...
Article
September 17, 2001
Designing progressive dies
Figure 1: This part was rotated in the strip to maintain critical tolerances better. The decision to produce a part progressively is usually determined by two factors: the volume of production and the complexity of the part. These two factors are instrumental in the design and... Read more...
Article
September 17, 2001
Working safely with metalworking fluids
Metalworking fluids (MWFs) are widely used in many manufacturing industries. These fluids are used in the cutting, machining, and grinding of metal parts to cool and lubricate tools and workpieces, wash away the removed metal, prolong tool life, and prevent corrosion of the workpiece.... Read more...
Article
September 17, 2001
Designing large die sections with reparability in mind
Figure 1: Wire EDM can be used to produce a blank-through die opening such as the one illustrated here, except for the screw holes. Each of the four die sections is designed with two dowels to provide locational accuracy. Conventional die-sinking electrical discharge machining (EDM)... Read more...
Article
September 17, 2001
Article
September 4, 2001
Standardizing finger tooling
Figure 1: Tooling is mounted to transfer rails by receivers, which provide mechanical, electrical, and pneumatic connections. Improvements in transfer press automation and the availability of used large-bed presses for retrofitting have accelerated the use of transfer presses with... Read more...
Article
August 16, 2001
Improving in-press transfer preformance with tooling
Figure 1A: Traditionally, pins and heel blocks have been located as far outboard as possible. Figure 1B: Different locations can be used, depending on the application. Critical path planning and project management time lines influence most projects, including transfer systems and... Read more...
Article
July 26, 2001
Know your bending basics—Part II
This article is Part II of a two-part article on die design for bending.
There are several good ways to design a tool to achieve a 90-degree bend. Whatever method you choose, you must be able to adjust the tool easily in response to variables discussed in Part I of this series.
To... Read more...
Article
July 26, 2001
Tool design tips for coated stampings
From time to time designers and manufacturers of progressive or stage tooling are faced with a project involving production of metal stampings that will be post-processed with painting, powder coating, or plating operations. Customer requirements for postprocess finish quality often are... Read more...
Article
June 18, 2001
Article
June 15, 2001
Gas-shielded cored wires find their niche
Object Gas-shielded flux-cored arc welding (FCAW) and metal-cored arc welding (MCAW) are growing in popularity for many applications. To determine if these wires should be used, shop managers should understand how formulations of cored wires do or do not fit their quality requirements for... Read more...
Article
June 15, 2001
Article
June 13, 2001
Transfer die design considerations
After receiving an assignment to design a die for a transfer operation, a die designer considers many questions and factors concerning the specific project. These questions help the designer to create the best possible design for all the factors comprising the project. If annual volume, press... Read more...
Article
May 30, 2001
Discovering the limits of press brake tooling
One of the most important aspects of press brake forming is tooling selection. What are the tools capable of? What kinds of loads can they withstand?
Figure 1:
A standard straight press brake punch withstands more tonnage per foot than the press brake itself withstands.... Read more...
Article
May 30, 2001
Protecting dies against press system faults
Mechanical switches and grounding switches were among the first devices to be used for automated die protection. Early sensing systems based on mechanical switches simply opened the top stop circuit of a press when a fault was detected. These systems, however, offered no protection from faulty... Read more...
Article
May 15, 2001
Know your bending basics—Part I
Editor's Note: This article is Part I of a two-part series discussing bending. Read Part II .
Of all of the operations that typically are done in a stamping die, it seems that achieving and maintaining a 90-degree bend are two of the most difficult.
To accomplish these tasks... Read more...
Article
May 15, 2001
Hydroforming of tubes, extrusions, and sheet
Hydroforming tubes, extrusions, and sheet metal is a state-of-the-art enterprise and is just now becoming more popular in the industrial production of frames for light trucks and vans. Figure 1: Hydroforming tubes with outer pressure, though not the norm in the industry, has several... Read more...
Article
April 24, 2001
Article
April 24, 2001
Exploring upgrades in stamping presses
Model Ts are an example of a once-modern mode of transportation that have become a collector's possession and museum lore. Industrialist Henry Ford gave the world access to mobility and freedom to travel; however, vehicles today have improvements that make the formerly innovative Model T an... Read more...
Article
March 23, 2001
Selecting a new press brake
You have realized for a long time that your company should consider buying a new press brake. Now you have the responsibility of developing the specifications and recommending a new machine. This is an awesome responsibility, because if you select the wrong machine, your manufacturing costs... Read more...
Article
March 5, 2001
The basic elements of tubular hydroforming
Tube hydroforming has been well-known since the 1950s. However, with recent advancements in computer controls and high-pressure hydraulic systems, the process has become a viable method for mass production, especially with the use of internal pressures of up to 6,000 pounds per square inch... Read more...
Article
February 19, 2001
Article
February 19, 2001
Article
February 19, 2001
Article
February 19, 2001
Cutting die-related costs: Where to look to save money
I want it cheaper. I want it better. I want it faster, preferably yesterday. The pace of business in the metal stamping industry continues to escalate. And the trend is not going to reverse. Balancing cost against quality and time can be a real challenge. Add to that the pressures of... Read more...
Article
February 19, 2001
Auto industry demands shape the future of stamping
Editor's Note: This column was prepared by the staff of the Engineering Research Center for Net Shape Manufacturing (ERC/ NSM), The Ohio State University, Professor Taylan Altan, Director. As we face the 21st century, the stamping business continues to be driven primarily by the automotive... Read more...
Article
January 15, 2001
How to draw round cups deeper
Figure 1 : In deep drawing, sheet metal is forced into a die by a punch to form a part. The draw ratio decreases throughout the process. In general, deep drawing (see Figure 1 ) is a process in which a blank is forced into or through a die by a punch to form a hollow component that... Read more...
