Some our our manufacturing processes have extensive setup time, and often times it is not deemed ‘worth’ it to change into a setup only to process one day of demand.
There are likely many ways to solve this problem. It seems like ‘Days of Supply’ could be a viable answer.
In practice though, at least for the way we do things today, no matter what we set a parts days of supply value to, we are still ultimately beholden to the frequency at which we run Process MRP, which happens to be nightly here. I am not sure how viable it is for us to change our Process MRP schedule. We receive new orders constantly throughout the day, every day. Because of this, MRP will wind up always generating supply for one days worth of demand each day, effectively negating the effect of the days of supply setting.
I think a lot of our issues stem from the fact that the lead time we offer our customers doesn’t totally jive with our parts actual lead time. We do not really have the luxury of not acting immediately on new supply records in the hopes more demand for the same thing will come in the next few days to get the most bang for our buck when changing into a setup. If we wait for that, we run the risk of waiting too long.
This issue doesn’t seem unique. Wondering if anyone else has any thoughts/feelings/suggestion.
This is a business problem, not an MRP or even an ERP problem.
The only answer is going to be a “lesser of evils” kind of thing. Essentially, are you better off holding additional finished goods inventory to handle orders within manufacturing lead time? Using a Forecast or an MPS will give you signals to get your raw materials and manufacture the finished goods, which you would then keep in stock. You have the ability to level-load your shop and stay out of “hair-on-fire” production mode… BUT at the financial cost of higher inventory levels AND the possibility of having obsolete product.
Any angle I approach this from seems to end up at that exact decision, “hair-on-fire” vs heavy inventory.
Another option I have been thinking about lately is leveraging the min lot size/lot multiple fields to write jobs for quantities that are ‘worth’ performing a setup for. This of course has the con of heavy inventory but something has to give somewhere.
Just the min/max/multiple lot sizing by themselves won’t help, you also need a trigger to create the job in the first place. Those values will create jobs of specific production quantities (hopefully in the “economic build quantity” arena) BUT ONLY if the job is required by some demand… a Sales Order, a Min On-Hand quantity, a Forecast, or an MPS.
Yeah that is one of my specific issues. My jobs are triggered by demand, but the quantities required on a specific day are often not deemed ‘worth’ it for the trouble of changing into a setup.
In the past, and even now, attempts to alleviate this have involved running multiple jobs that fit into the same setup in succession, even if those other jobs are slated to start some time in the future. Running jobs ahead of schedule comes with it’s own set of problems, which I am trying to avoid.
Days of Supply seems like a more correct way to take what would otherwise be future supply records and accurately group them together. Essentially do what we are doing artificially today and have it reflected more accurately in the system.
Min lot sizing would kind of do the same thing. I am of course counting on there being future demand, but I am (hopefully) getting more value out of the effort of going into a specific setup.
Running MRP too often can sometimes be self-defeating. This can be amplified more when lead times are short. With demand trickling in with short lead times, a short days of supply, lack of minimum order quantity for the customer, and running MRP daily, you may find yourself not able to truly leverage the Days of Supply to its fullest.
Min Lot Size and/or Lot Size Multiple can ease that pain a bit, but at the cost of carrying a bit more inventory of your finished goods but possibly in a more efficient manner.
Are you currently getting increase/decrease, expedite/delay suggestions against your existing jobs? If so, is anyone reviewing them, or is there even time to make adjustments? Maybe experimenting the the Reschedule In/Out Deltas could be helpful.
Other possibly helpful variables:
forecasting and/or master production schedule
setup groups for other products with similar setups
I am starting to realize this, but you touch on the reason why running it less often may not be viable when you ask if we even have the time to react to job change suggestions. In most cases, we do not. So by extension, we do not really have the time to not act immediately on new demand.
I have been looking into forecasting for our large volume items and for customers that have a particularly egregious lead-time agreement. While it does seem effective, it does require a significant amount of human interaction.
Minimum order quantities seem like an elegant solution to me, but I understand why the thought of placing any kind of barrier on sales causes people to recoil.
I think the exact problem I am trying to solve is the fact we offer unrealistic lead-times to our customers. I do not expect this to change.
The problems I am trying to avoid basically stem directly from the problem I can’t solve.
At a very basic level, I really think Epicor is counting on me to not do the thing that we are doing. which is a totally normal expectation. Seems like a no-brainer to me.
Trying to get Epicor to help us be successful, while doing this very basic thing wrong seems to be at the root of our struggles, and why any solution only ‘kind of’ works, and inevitably comes packaged with some kind of downside.
Excellent. And no, you probably can’t change the unrealistic lead times problem. If it helps at all, you’re not the first to be smacked upside the head with this issue.
Before messing with the software, let’s look at the OTHER process issues in play here. You said earlier that production doesn’t think small quantities are “worth” doing the set up for. If that decision is ALSO not up for discussion, and they will ONLY build quantities that are “worth” the setup, then you are either going to be late with deliveries some of/most of/all of the time OR you have to hold additional inventory. No software can solve that dilemma, and the ones who are in charge literally need to decide which way they want to go.
The software (Epicor or anyone else’s) is not magic. It will do what you tell it.
EDIT: each of those options has a cost. The additional inventory option is an extremely visible cost… the continuing late deliveries is a somewhat harder to quantify, but it exists.
They are making compromises here. We are slowly but surely trying to operate in a way that goes by what Epicor lays out, rather than what they used to do, which involved an exorbitant amount of human manipulation of jobs and schedules and on and on.
On the surface, the trade off for removing all of that manual work, and effectively having all of our what/how many/when figured out automatically by Epicor, is that our operators now spend a larger portion of their day performing setup activities rather than producing parts.
I am capable of understanding that that scenario is not immediately worse than doing things the old way. It is not fair to point out we now produce less parts in the same amount of time while ignoring all of the work that went into our operators being more ‘efficient’ with their time to begin with, which is now basically eliminated. Not even getting into the consequences of running jobs and consuming materials ahead of schedule.
That does not mean that I can ignore someone who is pointing at this and telling me this is less efficient. This is really the driver behind me trying to find ways to correctly bend Epicor to the way we want to do things, rather than just demand we change our methods to fit into what Epicor intends.
Lately it has become more and more apparent to me that our real problems stem from issues that no ERP can solve, but as long as I’m here I might as well try.
heh. I run a nightly full regen, plus net change (solely looking at the next month) every 2 hours during business days. Because we have some work that is extremely long lead (with leads and days of supply measured in months) and others that have a turnaround of a few days (including engineering) so capturing that new order ASAP is actually important because every minute counts.
Can’t say I’ve seen any issues with Days of Supply. Our Time Phase has never looked better. Can you elaborate?
How accurate are your costs and estimates? You should be able to “know” what the margin is on your sales to support your decisions. If you don’t have accurate ones, I would recommend working on that first so you can get good data out of the system.
Not saying this is happening where you are, but I have come across situations where the operators complain to management about the setups because they don’t like doing setups. And since they complained the loudest, they got what they wanted.
Instead of doing minimum order quantities, you could provide the “optimum” order quantity and offer that at a lower price. As long as it stays within your margin range, why not try to sell more?
If you have the processes in place to support all the changing data that multiple daily MRP runs generates (you obviously do), and all that data is useful and helpful in running your business (it obviously is), then more power to you!
However, simply running MRP more often with no additional structure in place for the added output just starts to make people cranky.
It’s not always a problem for everyone. What can happen though, is that sometimes there isn’t enough time between MRP runs to aggregate that demand orders into a single supply order and you end up with multiple supply orders inside your Days of Supply. This can true on both purchase and job suggestions.
