Powder
Printing & Registration Can Seaming
Seems Reasonable
From Can Networks in our Multi-Grain Filler Case Study to Can Seaming in this one, here’s another example of Machine Upgrading in the Powder Industry to preserve Raw Materials and Uplift Functionality. Once again, the client wish was to maintain the mechanics of the machine as the Machine was Mechanically Sound.
This is a very reasonable client request, not least from a perspective of respecting nature and preserving both fit for purpose Raw Materials and Workmanship.
What was unfit for purpose was the System, so the Specification was to negate the need for a new machine with a robust upgrade on a site producing nutritional powder for post-surgery patients.
Can Seaming
Can Seaming Project Specifications
Can seaming is the process wherein the lid of a can is joined to the body of a can to create an airtight seal.
As such, this process is used to maintain contaminant-free environments for products. Here is the Specification outline:
- Increase productivity from 30 cans per minute to 50
- Simplify maintenance by increasing the diagnostics on the machine
- Ensure that the machine meets the latest safety standards
- Increase reliability and therefore machine availability by reducing downtime
- Prevent the main seaming motor from over-heating
- Detect the level of oxygen in the can before sealing to increase product shelf life.
Can Seaming
Oxygen Measurement
To overcome the problem of product shelf-life, the product is filled with nitrogen to remove oxygen from the system.
However, the client had no way of knowing how much oxygen was in the can before seaming.
We therefore introduced an oxygen measurement system with a transmitter that was then connected to the PLC.
Can Seaming
Safety
Previously the operator was able to open the guard doors while the machine was running. Even though this would stop the process, the system did not account for the ramp down time of the motors. This presented a risk of injury to the operator. At 2M we proposed the following:
- Increase the robustness of the doors by increasing the thickness of the Perspex doors from 3mm to 10mm
- Introduce a magnetic safety gate system with a holding force of 500N
- Introduce a safety dump valve to dump the air in the system when the guard doors are open
Ramp Down Time means the duration (measured in minutes) the flexibility asset (or pool of flexibility assets) take(s) to change output from the instructed output (demand or generation) to normal operating output at the end of service delivery.
Can Seaming
Going Forward
The best production speed we could achieve with this method was approximately 40 cans per minute. Higher speeds were observed to reduce the seaming quality.
2M proposed to change the Seaming Motor from a standard AC Motor to a Servomotor to deliver the speed and quality the client desires.
In summary, an existing machine was upgraded to increase speed from 30 to 40 CPM, meet SIL3 safety levels and EU Machine Directives, be accessed remotely by engineers to diagnose faults, and seam all cans to contain the right amount of Nitrogen for a guaranteed shelf life.
This was also yet another Reverse Engineering project for 2M as there was no machine software back-up. Therefore, a Solution was designed by observing the machine and collating information from Operators and Maintenance Engineers.
Multi-Grain Filler
Sugar to Spice
2M received a client enquiry to convert a machine from filling sugar jars to jars of spice.
Operators had found that it wasn’t a simple switch as fully filling jars with correct weights of spice was taking much more work to insure using the current System. Specialist Spice-Filling machines were available on the market, though they were of considerable cost, alongside their specialist Training.
Therefore, this presented a great opportunity for 2M to cleverly maintain as much hardware as possible to give the existing machine a new and bespoke lease of life.
Multi-Grain Filler
Settling & Tamping
2M needed to design a solution within the machine that would see the jars:
- shaken during the filling process to “settle” in the bottom of the jar, then
- a second phase that would see the spices “tamped”.
Tamped: to press something such as soil or tobacco down firmly.
“Tamping” therefore removes any air that has entered the jar when being filled. This is what ensures the accurate filling of the spice jars with precise and consistent weights of spice.
Multi-Grain Filler
Schneider Kit
As the machine was already using Schneider components, to save raw materials and costs 2M decided to maintain the Schneider cables and motors whilst updating the drives instead in order to:
- get the latest version of the hardware, and
- gain access and communicate with the drives in order to get the relevant data such as frequency and current etc.
Therefore, existing motors and cables were kept as opposed to being gutted and removed before their time.
Multi-Grain Filler
Alleviating Uncertainties
Software was used to convert the drive data from the Schneider Servo Drives to the same format as the B&R Servo Drives being used.
Multi-Grain Filler
Can you explain what a "CAN" Network is?
Last but not least, was the challenge of standardizing the signalling throughout the machine which had been built in China with some signalling differences compared to Europe.
2M used the CAN network to ensure that all controls such as weight control and safety controls were in one controller so everything ran through the same software.
A CAN network is a communication system that allows multiple electronic devices in a vehicle or machine to communicate without a central controller.
CSS Electronics very interestingly describes the CAN network this way:
Let’s imagine your car is like the human body:
The CAN bus is the nervous system, enabling communication.
Speaking of nervous systems, did you know that the purple petals of the Borage plant have long-been brewed to calm & settle the nervous system? Meanwhile, a dab of cayenne pepper powder now and then ensures the diffusing of any micro-clots in the pathways of the heart.
A machine was even taken off production and set up at 2M to finalize the development and testing in a controlled environment, with the result of this project being a versatile and reliable Multi-Grain Filler.
