Lot Code for continuous process

Need some of my peers expert advice:

We run a continuous mix operation and I am over thinking how to lot code the finished product.

How do I handle new lots of raw materials in relation to the finished goods lot numbers?

Do I issue a new lot number periodically (every 12 hours) during a production campaign or do I change the lot number relative to the inputs to the process.

Thanks in advance for the feedback.

Need some of my peers expert advice:

We run a continuous mix operation and I am over thinking how to lot code the finished product.

How do I handle new lots of raw materials in relation to the finished goods lot numbers?

Do I issue a new lot number periodically (every 12 hours) during a production campaign or do I change the lot number relative to the inputs to the process.

Thanks in advance for the feedback.

Hi ganderson,

Time has been used in several of previous related threads.

But I daresay other methods will shortly appear. :smile:

Hi ganderson,

                     As Charles states time is probably the easiest method with changing lot code at midnight.  Ultimately as long as you are able to trace the product back from the finished goods lot code that is the most important thing.

If you have time on raw materials entering the continuous mix and then time on finished product and know the lag between the 2 that should give you a pretty good idea.

Ultimately simple is better as what ever you decide others will need to follow!

Neil

Hi Ganderson,

As stated previously the simpler the better, but your lot numbers can be anything you want as long as you can confidently trace your products/ingredients at all steps in the process.

Murae

Hi Ganderson

You also need to consider the volume of product you are prepared to lose should you detect a problem after the fact, ie a days production v's half a day.

We use a julian date code and 24hr time code, this gives us the ability to reduce issues down to specific time frames

Sharon

Your finished product lot needs to be a well thought out simple method that will tell you what you need to know to be able to do a product trace. Great receipt, point of use and process records prevent tying the raw material lots into the finished product lots but the main thing is to design your system so it works for you. From my experience, the more complicated it is, the easier it is for mistakes to be made.  Lot numbers are also sometimes limited to a certain number of character spaces if you are using a computer trace system. 

I am sharing our method for lot coding, not because I think our lot number system is the way to go (having a 24 hour time stamp would be great) but because I think hearing what others are doing is helpful.  Our process is much like Sharon's only we use Julian Date and Process Line (which also tells the shift based on the number.  Meaning we have 9 lines so numbers 11-19 means first shift, 21-29 means 2nd shift and 31-39 means 3rd shift for our lots.  An example of our finished lots code: 1603311; by that code I can immediately tell you (after looking at a calendar with Julian dates :)) that the product was produced on FEB 02 2016 during 1st Shift on Line 1.  We also have a behind the scenes trace method if we can get pallet numbers to trace product to more specific times.  We record the raw material lots that are supplied by the supplier at receipt and retain them throughout our process to include when used (date and time) and on what process line so that we can trace what finished product they were used in.  

The OP was –

How do I handle new lots of raw materials in relation to the finished goods lot numbers?

As I understand the raw materials (solid/liquids?) are (somehow/somewhere/sometime) comingled. Without knowing some details it is difficult IMO  to see how the OP can be answered in a very meaningful way. Hence i guess  the appeal of gross descriptors such as time.

Just as an example I recall some previous threads involving silos continuously being topped up. From memory, on the “micro” level,  it was necessary to visualize layers of raw materials moving through the container at the nominal flowrate but with  a factor/assumptions to express the overlap of layers due mixing. On the “macro” level you simply had a time period where certain lots of inputted raw material were estimated  to be “most likely” to be present in the output.

Clearly further variations  in subsequent activities such as packaging will introduce ever more variables on top of the original varying stream.

Theoretically looks like a "typical" situation  of (somehow) compounding mixing variances due to stages  x1, x2, x3  etc. Practically, i suspect more likely a case of educated guesswork.

I anticipate that tagging exercises on incoming lots (Rfids?) have been done to evaluate the achievable accuracy of the OP's request ? It's clearly a fundamental Traceability problem.