Here are some tips for a successful Factory Acceptance Test (FAT) for form/fill/seal equipment:
1. Furnish a FAT plan.
The FAT is the time to discover failures or issues, determine reliability, verify efficiencies, and explore how the machine should handle failures. This plan actually should be prepared up front and submitted to the supplier as part of the Request for Quote (RFQ). Although you’ll pay for the test, most equipment suppliers will agree to a provision that if the machine fails, any subsequent test is free. Your test plan should specify how long the machine should be dry-cycled (24 hours recommended), and how many packages should be produced and at what speed—in other words, the length of time (two-minute stress runs, no more than five minutes for quality production runs, etc.). It should also specify disposal plans for the finished packages.
2. Know the difference between a Factory and Site Acceptance Test.
One of the biggest areas of confusion surrounding the FAT is if it should simulate how the machine responds under actual factory conditions. That’s actually the purpose of the Site Acceptance Test (SAT). In the machinery builder’s plant, it may be difficult or even impossible to simulate both the production volume and the conditions of your product, especially for more than a few minutes. This is especially true if the product will be packed at a certain temperature, or has a certain consistency or rate of speed coming out of an oven, fryer, or freezer. Much time, energy, and money have been spent in vain trying to address “failures” in the machine builder’s plant, only to find that the machine works perfectly once in production at the customer’s plant.
The purpose of the FAT is to verify the desired functionality of the machine. The purpose of the SAT is to confirm that the machine runs your product to your specifications in its operating environment. Knowing the difference can save you and the supplier time, money, and aggravation.
3. Ensure you’re using the correct film.
Use the film that will be used during actual production.
4. Train the right people.
If training is provided as part of the FAT, make sure those being trained are the production people who will run the line, not the engineers. Also, consider a “train the trainer” strategy as part of the FAT process before the equipment even ships.
5. Test part replacement.
Test how long it takes to replace the most common wear parts. Determine how to remove a defective part.
6. Assess safety.
Complete a review of the equipment from a safety perspective. Look for poorly guarded areas and pinch points. Run your hands across the machine (carefully) to detect sharp edges and burrs. Is making the machine LOTO (Lockout/Tagout) easy to accomplish, or are there unexpected sources of energy that could cause injury?
Lockout/Tagout refers to the act of disabling all sources of energy, such as electricity and compressed air, while physically locking down the machine so that it doesn’t cause injury due to movement while the machine is being worked on.
7. Assess the design rigorously beforehand.
Because of the difficulty, if not impossibility, of replicating the factory environment with exactitude, consider the FAT for what it is: an approximate test. Just as important are the design intent, specifications, and execution.
8. Follow a detailed “failure” script.
This can be time-consuming, but is important. Make an inventory of the type of failures that you’ve experienced or might experience, as well as expected outcomes. For f/f/s equipment, this checklist could include:
- Hit the e-top, and then restart it. Ensure the machine doesn't jam itself on start-up, and that there are few or no wasted bags.
- Trigger or block each sensor to see how the machine responds and restarts.
- Starve the machine of product to see if it stops producing bags.
- Break the film web to see how the machine responds.
- Disable the knives to prevent them from cutting; see if the machine detects bags being made without being cut.
- Block the date/lot code from being applied (if applicable). Does the machine detect the bag with the missing code?
- Induce a failure in the auto splicer (if there is one) by cutting the film web halfway through. Does the machine gracefully shut down?
- Run the machine at very low and very high speeds. Are there critical differences in the way it forms, fills, and seals a bag?
Also examine the physical characteristics:
- Did it fill the correct amount?
- Does the filled product look presentable (if it's a clear bag)?
- Is it a clean seal?
- Is it a clean cut?
- Is there any crushing?
- Are there any leakers?
