A die manufacturer created a 12” wide by 24” long (30.5cm X 61 cm) tool for an injection molding machine that contained 80 cavities for an automotive supplier. As contracted with their customer, the goal was to have 30 injection per minute to create 2400 parts every minute. The tool was designed with 2 chambers, each containing 40 cavities to control production rates. Also as part of the contract, the automotive supplier required a pre-production approval before signing off on the purchase order. As they attached the tool to the injection molding machine for a trial run, they began to notice that some of the parts were sticking to the cavities. In the first 30 minutes, they stopped the machine as they only averaged 16 injections per minute with only 50% of the parts falling out of the tool. They did notice that they could feel the static electricity on their arms when they reached into the tool to remove the parts. To try and improve the cycle rate, they attempted to mount a 12” (30.5 cm) pipe with drill holes above the tool. Many manufacturers attempt this because it is simple and easy to do; but, this style of blow-off is very inefficient and not very effective. As they began the next trial, they did see a slight improvement. It increased the cycle rate to 19 injection per minute and it was removing 75% of the parts. It still was not good enough for the automotive supplier.
The die manufacturer was under pressure to find a solution as he did not want to redesign or rebuild the tool. He noticed that EXAIR was a leader in Static Eliminators and Blow-off equipment, so he contacted us. In our discussion, he explained how he needed to remove the static and remove the parts quickly out of the tool. I suggested our model 111212 Super Ion Air Knife Kit. It is 12” (30.5 cm) long, and it can be mounted easily across the width of the tool. With a 40:1 amplification ratio and both positive and negative ion streams, it can remove the static and push the parts very effectively. Once they installed the Super Ion Air Knife, they began the operation once again. They initially noticed that all the parts were being ejected from the tool. When they measured the cycle rate, it was running at 33 injection per minute (exceeding the requirement). The tool was approved and the die manufacture was very pleased.
When it comes to removing static and blowing parts, EXAIR has a great range of products. We can do it very efficiently, quietly, and effectively. If you have any issues with injection molding, EXAIR may have the product to help you. You can discuss your applications further by contacting one of our Application Engineers.