When it comes to die stamping, friction generates heat. Heat can be a big cause in slowing production and decreasing tool life.
A reel manufacturer was seeing the effects of the heat in their process. They had a stamping machine that was creating sprocket holes in the outer edge of a 35mm film. These holes are used for advancing the reel strip through printers, projectors, and processing machines. They had to be particularly careful, as film materials warp easily with heat. Some of us remember the film reels that would bubble and burn out when the film stopped in the projector. (I am giving away my age a bit). So, speed was critical as they did not want to create any quality issues.
They were intrigued with the EXAIR Vortex Tubes as it can generate cold air by only using compressed air. Vortex Tubes do not use refrigerants or have any moving parts. They are very compact and can fit into tight places. If they could reduce the temperature in the stamping process, then they could speed up production.
With the Vortex Tubes, EXAIR adds accessories to help with installations for different applications. For this customer, the Cold Gun Aircoolant System was the best product to deliver the cold air. I recommended the model 5315 Cold Gun System. This product generates 1000 BTU/hr of cooling power, and it has a Dual Point Hose Kit to target both sides of the film reel. It includes a magnetic base to securely position it on the stamping machine, and two 1” flat nozzle ends to attach at the end of the Dual Point Hose Kit. These flat nozzles would help to direct the cold air in between the two stamping plates. They were able to keep the film reel and the die stamp cool as they sped up their operation. Even with the additional speed, they also noticed that the die stayed sharper 20% longer before they had to rework.
If you believe that heat is slowing down your system, EXAIR may have a product to keep it cool. With the customer above, heat was a “reel” problem. With the Cold Gun System, we were able to increase their productivity and decrease their downtime. You can contact an Application Engineer to discuss your application if you believe that temperature is affecting your process.
Over the last 3 months, I have been in contact with a customer, keeping track of an application that involved the EXAIRE-Vac. The customer had reached out to us looking for some advice on how to solve a process problem. The operation is a drawing/stamping process, and the when the part exits the machine there is coolant that resides in a deep draw section, approx 0.4″ in diameter by 3.5″deep. About 1 oz of coolant per part is retained, and over many 1000’s of parts, would add up to lost dollars and messy clean up.
The customer was looking for an automated process that would be able to draw out the coolant and direct the liquid back to the coolant reservoir, all while maintaining the current machine run rate. We settled in on the model 840015 Adjustable E-Vac Generator. The Adjustable E-Vac has a straight through pathway from suction through to discharge, allowing for fast evacuation times. A simple turn of the unit changes the vacuum and flow levels to best match the needs of the application. The Adjustable E-Vac coupled to a solenoid valve controlled by the stamping machine resulted in the automatic system the customer was looking for.
The customer ordered a unit, and based on the preliminary bench testing, it was approved for a production run trial. After some tweaking in the production environment, the unit was performing to spec, and was then subjected to a 100,000+ part run. The results were a success! Instead of the parts exiting onto an inclined conveyor, relying on gravity to drain and causing coolant to collect under the conveyor, the coolant could be removed in a controlled manner and sent back to the reservoir. Less mess and no coolant loss.
EXAIR manufactures (3) types of E-Vacs – Low vacuum generators for porous materials, high vacuum generators for non-porous materials, and the adjustable type for flexible vacuum performance. They are available in multiple sizes, to best match the vacuum requirements, while using the least amount of compressed air.
To discuss your application and how the EXAIR E-VAC can benefit your process, feel free to contact EXAIR and myself or one of our other Application Engineers can help you determine the best solution.
A stamping facility had a high speed perforating operation. The idea was to punch holes into a matrix at a fast feed rate. In their operation, they started to see issues with the punched holes, and they also noticed that the punch points were prematurely failing. With a tight punch-to-matrix clearance, heat was building up from the friction. This effect was galling the material and affecting the hole appearance and dimensions. They also noticed heat damage to the punch points. They either had to slow their process down, or find a way to cool the punch points. They contacted EXAIR to see if we could help.
To remove heat, you need to have a fluid moving across the material to carry the heat away. For this customer, the fluid would be air. Just like a hot cup of coffee, you can cool it by blowing across the top of it. In this instance, EXAIR can blow a lot of air with using very little amount of compressed air. Because of the gap opening of the tool die was narrow, I suggested the Super Air Knife. It has a compact design and can blow nicely between the upper and lower die. With slight modifications, they were able to mount the Super Air Knives right into the base set. Because the tool die was a “bowl” type design, I suggested that they should use two pieces of the model 110206 Super Air Knife. They could mount one to each side to make sure to hit all the punch points. (Reference the picture below).
EXAIR Super Air Knives are the most efficient compressed air knives in the market. It is designed to have a 40:1 amplification ratio. That means for every one part of compressed air, it will entrain 40 parts of the free ambient air. As with the coffee reference above, the more air that you can blow, the better the cooling effect. With the Super Air Knife, we can reach a velocity of 11,800 feet per minute at 80 PSI. After the customer installed the Super Air Knives, they were able to increase production by 10%. Also, they found that the punch points were lasting twice as long. They were so impressed with the effectiveness of the Super Air Knives, they mounted them to all their punch press machines.
If you find that heat is affecting your process, EXAIR could have a product to help you. We have a variety of efficient air movers to cool your parts. As for this customer above, we were able to increase production and extend the life of their tools.
A stamping company contacted me for help in their ejection blow-off system. Their operation consisted of a punch press that would form two 8” X 8” triangles from a square piece of metal. The operation of the punch press was to cut the square piece diagonally at the same time forming the outside edges of the triangle. At the end of each stroke cycle, the formed parts would then be blown off the die with compressed air. The blow-off system consisted of two pipes, one that was a ¾” NPT pipe and the other that was a ½” NPT pipe. They both had the ends of a long nipple flattened to concentrate the air flow. EXAIR has reduced air use, saved money, and lowered noise levels for many similar applications by replacing open blow-off devices with our engineered air nozzles.
In giving me more details about their operation, the system had a timing sequence that controlled an actuator. When the cycle was complete, the actuator, located below the tabletop of the punch press, would open and send compressed air through both pipes. The positions of the blow-off pipes were designed to eject one part off the side of the die and the other part off the front of the die into a collection chute. (Reference the picture below) They were having issues when their blow-off system wasn’t consistently able to eject the 1 lb. part completely off the die. In manually having to remove the parts, it would cause an unsafe environment as well as a slowdown in operations. They found that EXAIR manufactures Intelligent Compressed Air Products and wondered if we could help.
With a lack of restriction at the end of the pipe, the air pressure will drop quickly as it travels through a relatively long length of pipe. The actuator, which was more than 3 feet away from the end of the pipes, had a line pressure of 90 psig (maximum that they could supply). By the time the compressed air reached the ejection site, the pressure was much lower; thus, not quite removing the part from the die. An example that I like to use is a garden hose attached to a spigot outside your house. As you open the spigot, water will flow out of the hose at a slow velocity; not very strong, that is the same as air through an open pipe. When you place your thumb partially over the end of a garden hose you restrict the flow and increase velocity. Engineered nozzles from EXAIR work the same way. They restrict the flow at the nozzle, increasing the pressure for a more effective velocity and blow-off force. Neal Raker wrote a great blog for EXAIR referencing how the nozzles work; called “What’s in a Nozzle?”
I recommended the model HP1125, 2” High Power Flat Super Air Nozzle. It has a 2” wide air stream to allow more contact against the side of the triangle edge. It has a force of 2.2 lbs. at 80 psig which is more than enough to eject the 1 lb. formed part. As an added benefit, it only has a noise level of 83 dBA which is magnitudes more quiet than the open pipe. Also in using the engineered nozzles, they were able to use much less compressed air in their blow-off, saving them over $1,000/year. If you find that your open pipe blow-off is too loud, not effective, or uses way too much compressed air, you should contact an Application Engineer to see which engineered nozzle would best suit your application.
At EXAIR, we get asked a lot of interesting questions about what our products can do. One of them that occurs with some frequency is, “Can your Line Vac convey slugs from a stamping operation?” The answer is usually yes as “slugs” (the material punched out of a sheet of stock to create a hole) are well suited in size, shape and weight to be conveyed effectively with the Line Vac product. We are used to this question from folks who are processing various types of metal sheet. The slugs tend to build up within their tooling and basically get in the way, if not even jam up the tooling from time to time. So getting rid of them from the process becomes a necessity that is, many times, not addressed during the tool making process.
Recently, we had another customer with this same kind of problem with foam. They were processing a foam sheet by punching a many holes in it which generated the waste stream you see above. Little pieces of foam about 8 – 10 mm in diameter and about 40 mm long. As you probably have guessed by now, the area that was set up to receive these renderings quickly became loaded full with the foam slugs. The customer needed to find a way to remove the slugs to a remote area so the receiving container could be switched out easily without stopping production. The original container was small, plastic bin about the size of a kitchen garbage can. The new receiving container was a large cardboard box that typically goes by the term Gaylord. The customer needed to set the Gaylord about 3 – 4 meters away from the die punching area. This is where the EXAIR model 130300 (3” Light Duty Line Vac) comes into play. The customer fabricated a chute that was positioned under the area to catch the slugs. The chute transitions to accept the 3” Light Duty Line Vac for connection at the bottom. Then, a 3” hose is connected to the output side of the Light Duty Line Vac so it could blow the slugs over to the Gaylord.
The customer chose the Light Duty Line Vac because it uses less air than a comparable size of our Standard Duty units. They didn’t need a tremendous amount of suction power due to the light-weight nature of the slugs. They also wanted a 3” unit to make sure none of the product would get caught anywhere within the conveying stream.
With the new Light Duty Line Vac installed, the operators do not have to spend as much time tending to the emptying of the previous, small containers that had to be used due to their size for fitting into the catch area. For an application where thousands of these slugs are produced in an hour, the productivity gain was significant. The customer didn’t place an exact value on the gain, but are considering this method for other, similar processes they have in the plant.