EPIC designed, built, and integrated a custom machine system with an existing production line to inspect dents on pressurized canisters and increase production rates for a major food and beverage company.
CLIENT: Fortune 500 Company
INDUSTRY: Food and Beverage
KEY ENGINEERING FEATURES:
- Custom machine designed, built and integrated into packaging line by EPIC
- Machine vision system with 360-degree view
- Custom form factor lighting
- Collimated lenses on cameras
- Color verification through machine vision inspection
- Graphic/art elimination for dent inspection
- Downstream tracking of rejects after machine exit
- Dent parameters definition 360 degrees can inspection
- High-speed application
The client required an upgrade of their can inspection from a manual to an automated process. The pressurized product would explode due to can surface defects.
Surface dents on the canister would impede the rising of a puck through the inside after it was filled with
the product. If the puck jammed, it could cause the can to explode and cause a delay in the packaging line for cleanup.
The visual human inspection could not detect many of the dents that caused the jams. Machine vision inspection offered higher detection rates, faster speeds, and minimized downtime.
EPIC completed preliminary design to assure the most efficient process and accurate cost quotation. After reviewing the objectives and challenges with the client, EPIC’s machine builders and engineers completed an analysis of the line and created an implementation plan that included the following elements:
- EPIC’s machine builders fabricating a custom-built rotary canister inspection machine to be integrated into the packaging line, before the filler
- A custom lighting solution including collimated camera lenses to wash out graphics for dent inspection
- Platens to rotate canister 360 degrees through a 180-degree turn of the machine
- Six overhead cameras to inspect canisters during rotation
- One camera located at the beginning of the machine to check for coating on the lip of canister and debris inside the canister
- One common reject station after canisters exited machine but before being filled with product
- Integration of a shift register with a photo eye-tracking system on the line to track rejects leaving inspection machine
EPIC’s Proven Solution
The custom-built rotatory inspection machine is integrated with the client’s packaging line before the filler. Cans enter the inspection machine through an in-feed screw, which spaces them correctly into a star-wheel. An overhead color camera inspects for the presence of varnish on the lip of the canister and checks for unwanted debris inside the canister.
From the star-wheel, cans are transferred to a platen which is timed to rotate a can 360 degrees within a 180-degree turn through one-side of the machine. Six overhead cameras scrutinize the can as it is rotated. The cameras are spaced and angled from above to capture a full 360-degree view of the can.
Cans are checked for dents that might impede the puck rising. A custom lighting set-up is required to complete the inspection. The canisters must be lit so that the camera is immune to the artwork on the surface on the cans. A custom form factor is used, with the circuit boards on the inside outer diameter of the domed machine. The custom lighting is on the inside inner diameter of the dome, and the can carousel is in the middle of the dome.
Defining the type of dent that might impede the puck is a difficult process for a machine vision integrator. A shallow but large dent or a small but sharp dent may stop the puck. These differences had to be combined into one fail process. The inspection machine has an 80% successful identification rate, which exceeded customer specifications. An 8th camera was added later to inspect for crushed or misshapen can lips.
If a can fails inspection, for missing varnish, debris, crushed lip, or dents it triggers a shift register. The shift register mechanically moves the ‘failed switch’ with the can as it continues through the inspection machine. Cans leaving the machine continue onto a conveyor.
The conveyor is unable to mechanically track ‘fails’ due to conveyor slippage. At this point, the shift register hands off the ‘fail’ signal to a photo eye system that detects the cans based on position in the queue. Rejects are eliminated from the packaging line after they pass a second photo-eye.
- Reduced number of faulty products
- Greatly improved ability to detect surface dents on cans
- Improved reliability of capping and better seals
- Reduced can explosion, line stoppage and problems in filler
- Minimized quality complaints
THE EPIC DIFFERENCE
EPIC provided expert insight during the design, machine build, automation, and start-up process. Because of EPIC’s experience in the field, we were able to recommend the correct custom parts, including the custom machine vision system, and prevent problems before they arose.
The EPIC Difference includes several key features that assure the success of a project:
- Front-End Engineering to ensure that the proper steps are taken during project scope development
- Plant engineering experience that assists clients to identify needs, pinpoint objectives and provide the most appropriate manufacturing equipment for the application
- Open door client policy to promote innovation. We invite clients to visit EPIC to experiment with new processes, technologies and techniques that push the limits of traditional engineering
- Accountability to responsibly manage our clients’ projects from start-to-finish and beyond
- A transfer of knowledge (not just a basic training) for the systems and equipment we provide
- Single point of direct contact during the entirety of the project
- A state-of-the-art shop which decreases down-time and increases the speed of project completion