Packing to Minimum weight
Hello Everyone,
We are manufacturing Ice cubes and packing to minimum weight .
I would like to know is someone has some guidance on minimum weight packing as at the moment we have plenty of weight checks and I am not sure if it is too much or not enough
Is there any percentage that we have to check depending on how many packs we do throughout the day or the hour ? As the weight and measures legislation does refer pretty much to average weight and provide guidance but not much about minimum weight.
If anyone can help that would be great .
Regards,
Oskar
We check bag weights (not ice, just snack like candy and mixes) every 30 minutes. This was driven by our customers requirements and an issue we had with one specific product getting off weight. At a previous job, we took 3 weights for every item we checked to get an average. This is also a good idea.
I would also recommend looking into an in-line check weigh-er that will kick off any bag that is not within the weight requirements. We are currently looking into one and believe it will be of great help.
If you want to get deep, you should engage in a statistical analysis to determine what the correct sampling is for the process. That involves math, so everyone, most people, some people, just me might just conduct a simple study to determine a threshold. I'm lazy as all get out, but if this were me, I would weigh 50 or 100 bags daily for a week and record all of the weights. How many of those bags are underweight, what is the average overage, etc? Then make some realistic conclusions about how that might translate into a QC check. For example, if 5% of your bags are underweight, the underlying process is too skinny and needs to be adjusted. If you find 0% under, then you could reasonably set a 2% audit rate as a starting point. Then, over time, you can use your results to justify reducing the checks if that makes sense, although not to a point of never having them. A lot of this comes down to what are the consequences of being underweight and how eager are you to avoid the negative consequences. That's balanced by the desire to not give product away and over-stuffing the bags too much. We fresh-pack fruit and we conduct an hourly QC process that includes weight measurements. As our average overage is 7% and the machinery checks the weight already, we could justify reducing that frequency, but since we need to check for decay, grade, etc., we just keep that check in place as it doesn't hurt and the cost involved in a rejection is high.
Anyway, that's my two cents, euros, pounds.
Good luck,
Todd
If you want to get deep, you should engage in a statistical analysis to determine what the correct sampling is for the process. That involves math, so
everyone,most people,some people,just memight just conduct a simple study to determine a threshold. I'm lazy as all get out, but if this were me, I would weigh 50 or 100 bags daily for a week and record all of the weights. How many of those bags are underweight, what is the average overage, etc? Then make some realistic conclusions about how that might translate into a QC check. For example, if 5% of your bags are underweight, the underlying process is too skinny and needs to be adjusted. If you find 0% under, then you could reasonably set a 2% audit rate as a starting point. Then, over time, you can use your results to justify reducing the checks if that makes sense, although not to a point of never having them. A lot of this comes down to what are the consequences of being underweight and how eager are you to avoid the negative consequences. That's balanced by the desire to not give product away and over-stuffing the bags too much. We fresh-pack fruit and we conduct an hourly QC process that includes weight measurements. As our average overage is 7% and the machinery checks the weight already, we could justify reducing that frequency, but since we need to check for decay, grade, etc., we just keep that check in place as it doesn't hurt and the cost involved in a rejection is high.
Anyway, that's my two
cents,euros, pounds.
Good luck,
Todd
Thanks Todd for looking into that.
However we already have a loads of checks in place which complies with our accreditation and our customer requirements . We have very few underweights we always trying to overfill the bags as we packing to minimum weight which is controlled by a volumetric control hence why we don't have checkweighers.
I just want to make sure that we are 100% compliant with the legislation for weight and measures but I can't find any specific data saying what percentage shall we check if for example we are packing 2000 packs per hour/per batch.
It must be something like a calculation based on the production like there is for the average weight checks.
If someone knows the math please let me know.
@OskarZabo
You might want to check out this thread about determining a statistical standard: https://www.ifsqn.co...ze-for-a-batch/
It seems to be a good place to start if you want to rely on stats.
Good luck,
Todd
Thanks Todd for looking into that.
However we already have a loads of checks in place which complies with our accreditation and our customer requirements . We have very few underweights we always trying to overfill the bags as we packing to minimum weight which is controlled by a volumetric control hence why we don't have checkweighers.
I just want to make sure that we are 100% compliant with the legislation for weight and measures but I can't find any specific data saying what percentage shall we check if for example we are packing 2000 packs per hour/per batch.
It must be something like a calculation based on the production like there is for the average weight checks.
If someone knows the math please let me know.
If you want to get deep, you should engage in a statistical analysis to determine what the correct sampling is for the process. That involves math, so
everyone,most people,some people,just memight just conduct a simple study to determine a threshold. I'm lazy as all get out, but if this were me, I would weigh 50 or 100 bags daily for a week and record all of the weights. How many of those bags are underweight, what is the average overage, etc? Then make some realistic conclusions about how that might translate into a QC check. For example, if 5% of your bags are underweight, the underlying process is too skinny and needs to be adjusted. If you find 0% under, then you could reasonably set a 2% audit rate as a starting point. Then, over time, you can use your results to justify reducing the checks if that makes sense, although not to a point of never having them. A lot of this comes down to what are the consequences of being underweight and how eager are you to avoid the negative consequences. That's balanced by the desire to not give product away and over-stuffing the bags too much. We fresh-pack fruit and we conduct an hourly QC process that includes weight measurements. As our average overage is 7% and the machinery checks the weight already, we could justify reducing that frequency, but since we need to check for decay, grade, etc., we just keep that check in place as it doesn't hurt and the cost involved in a rejection is high.
Anyway, that's my two
cents,euros, pounds.
Good luck,
Todd
hello, sorry I didn't see your thoughts until years later.
Would you be interested if there was a specialised software to do your job?
This is indeed a very specialised issue and we actually see this direction, however I still feel that the market demand seems to be very low.
Thanks.