“Discrete production” in a word really represents a variety of things, but let’s start with pigeonholing the discrete production.
To begin with, I’m going to think about it in terms of “degree of discrete.”
・Every time receiving an order from your customer, you start making all the drawings and telling that you have almost nothing to repeatedly use and so is your company with internal inventory. There’s a gung-ho discrete production such as this.
・Or, although they are different as finished goods in each case, their parts and materials to be used are just about the same. So, there’s also the production with parts and materials in stock to some extent.
・There’s also a case in which to handle with a combination of units as unitization goes along.
・A case where almost all parts of the products are the same, but only a part of them such as nameplate, ancillary parts, and lead wires changes.
・Furthermore, even a case where the product to be produced is a high-volume production item, but it is managed in a discrete manner (manufacturing number control) as the internal management method.
It is not uncommon that there’s a mixture of something strong and something weak in the degree of discrete in one factory depending on the product.
Let me think about the intensity of parts as another method of classification now.
・In the case of producing a product collecting a lot of pars, and
・producing a product processing one (or a little) material.
That is, whether materials and parts to be used are many or few is an important point that could affect the problem of the production control.
In addition, the method of processing one material can also be broken down:
・In the case of a completely different form and a different processing method in each case, and
・being possible in developing a certain pattern to some extent.
As how to manage is different in these cases, how to use TPiCS-X changes accordingly.
Since I can’t explain everything in this booklet covering all cases, I’m going to give you the explanation focusing on the case where multiple (a number of) parts and materials are used though
there isn’t a lot of repeatability.
In addition, when using the function of individual production, “f-MRP Mfg. No. Control System or Mfg. No. Control System” is indispensable.
If there is no repeatability and the MRP calculations are not required, you can build around the “Mfg. No. Control System”.
Handling short-term turnaround of new products, and engineering changes with TPiCS-X.
As I’m going to give my explanation based on the production in small quantity here, the “short-term turnaround” will be explained in the section (1) together in terms of “the production for short-term delivery = shortening entire work period.”
■ To begin with, let’s organize work from customer order to shipping.
① Design work → release of drawing,
② Production schedule creation, arrangements work, and filling in a form → purchase,
③ Delivery from a supplier,
④ Outsourcing operations, internal operations, and assembly completed,
and so on.
Now, in order to shorten the entire work period,
(A) Increase the pace of each work (shorten each work period,)
(B) Perform work in parallel.
The above is a theory.
■ Improvements in an aspect of the work.
● We are going to think about (A) Increase the pace of each work first as theory says.
The production control has a direct effect, in a narrow sense, only on ② Production schedule creation, arrangements work, and filling in a form. and filling in a form.
If there’s repeatability, you register master files in the system, and perform material explosion and process explosion using them. If there’s no repeatability, “you register master files first …” will require more work. If grouping is possible at least, you could have a way of developing a certain pattern out of it, and registering the pattern like a master to create data for arrangements using the master. If even grouping is not possible, you end up directly entering them from the keyboard like a word processor. Operability is all you need in that case. For example, you can get the data, like supplier information, among what is already registered by just entering the supplier code. Selecting it from the pull-down list, and dragging and dropping it sounds even better, and you will be far better off with that alone in doing day-to-day work. However, this function alone leaves you dissatisfied in so much developed IT environment.
And so we developed “Structure Information Conversion Option(CAD)” and One Item Production Option.”
Use TPiCS-X to import the product structure information for design written in the CSV file. From the imported data, you can create the original data of the arrangement without the operation of master registration, write the supplier, unit price, delivery date, etc., and directly create the Purchase Order Issuance data.
The CSV file is written from the CAD, if it has the bill of material information and can export it to a CSV file, or from Excel, if it manages the bill of materials, and imported by TPiCS-X.
These data of structure information are hierarchized, and if a new product uses an existing unit, just specifying the drawing number of that unit will do, and the data for grandchild components will not be necessary.
In this way, if you have the bill of material information in the CAD or the data of the bill of materials in Excel, arrangement work will improve and speed up dramatically.
● Way to use similar data in the past.
When you produced a similar product in the past and if you can use the data at that time, your work will go fast. If you use the data in the past, you usually have a few corrections. For example, the specification your customer has requested this time has a slight change; you must use a substitute item because the old part is discontinued; etc. In the one-item production option, after copying the past data, you change to this specification and create the Instruction Sheet data.
● Next, we’ll think about (B) Perform work in parallel.
The relationship between design and arrangement is the most important point in thinking about this.
Start your arrangements in the middle of design from wherever possible even if it is not all finished.
But I think that this is something many factories already put in practice.
The biggest bottleneck or something that causes trouble in doing this, however, is engineering change. Isn’t it?
Although the production control job is not so difficult individually, it becomes difficult as there are a lot of elements (parts,) and they act disconnected and constantly change.
If you use the Structure Information Conversion Option(CAD) and the One Item Production Option previously mentioned at this point, you can achieve the following processing:
Upon receipt of engineering change data,
・Unnecessary components in the above source data for arrangements get marked due to the engineering change, and only the unnecessary data are displayed upon click of the [Unnecessary] button.
・ New data for arrangements are created for the components that have newly become necessary.
・Displaying the data that have become unnecessary and talking about countermeasures with your suppliers, enter the outcome to each data.
・Release the allocation to the manufacturing numbers among those that can’t be cancelled and can be diverted to others, and put them into scrap disposal unless the diversion is possible.
・Issue cancel orders for those that can’t be cancelled.
You can easily process engineering changes that occur frequently in a large amount of arrangement data like this.
When hurrying up the design and hastening to make arrangements using the bill of material information (E/BOM) for arrangements, you will face a growing risk in engineering change.
It is very important to accurately and promptly notify your suppliers of the change. You might eventually cause a wrong arrangement and shortage to happen, which could have the opposite effect of the production.
As TPiCS-X can handle engineering changes this much as a system, however, it can solve this problem as well.
■ Improvements in an aspect of the production.
● Manufacturing number for order in advance.
There is a function of “Manufacturing Numbers for Advanced Orders (Unofficial Manufacturing Numbers)” in the Manufacturing Number Control System of TPiCS-X.
You can make arrangements for something, which has some repeatability but takes time in arrangements and production such as components and functional components, with the “Manufacturing Numbers for Advanced Orders” to some extent.
Having made arrangements beforehand with the Manufacturing Numbers for Advanced Orders, those unofficial manufacturing numbers can be assigned automatically when customer orders come in afterwards and assignments of official manufacturing numbers occur.
● When thinking about the production for short-term delivery in the discrete production, one of the most important things is whether or not parts and materials are going to be delivered as scheduled.
Needless to say, no shipments can happen if even a part is missing.
So in order to shorten delivery dates, parts have to be delivered as scheduled. And definite follow-ups are necessary for that.
With that in mind, I’m going to briefly explain the follow-ups next.
Since it’s the follow-ups to prevent delays in delivery, you can’t get anything done by making a scene after the fact. There’s the “On Schedule and Delay List” in TPiCS-X. It lists all outstanding orders, for example, that will have become due some time in the following week (depending on the setting.) Emailing it to your suppliers is possible, let alone printing it. If you register the mail addresses of your suppliers, you can send it to all your suppliers with a click of the button off the screen of TPiCS-X. Since it includes delays in delivery as well, it’s going be a sure follow-up.
Or, if you use the SCM Option, you can e-mail orders and “due date reply requests” to your suppliers.
If the suppliers use the terminal program (free) of the SCM Option, they can automatically receive your e-mail and send back their change request of delivery date with a click of the button off the terminal program. Then, you can automatically receive their change request of delivery date with TPiCS-X and apply the change to the Order Balance data of TPiCS-X again with a click of the button.
When the change is applied to the Order Balance data of TPiCS-X and if anteroposterior processes are reversed due to the delivery date change, you can immediately tell that you are going to need the readjustment of the schedule since it is displayed in red in the Gantt chart.
The readjustment of the schedule can be made by a drag-and-drop of the Gantt chart. Usually a lot of schedules become victim to this kind of readjustment of the schedule. Failing to send a notification of the result of the readjustment is even scary but with the use of the SCM Option you can send an email of the delivery date change to all of whoever suppliers to be influenced only with some clicks of the button once the readjustment is over.
Thus, you can constantly maintain the schedule to build the reliable, lean schedule.
As far as making the factory floor observable, essence is the same in the repetitive and discrete productions.
In order to achieve “observable,” it is necessary to always match the Schedule data in the system with the Execution Plan, and to keep the production as scheduled in the system.
For example, you can see the schedule in the Gantt chart. You can tell how far the manufacturing number has advanced with the Gantt chart. Even if the system has those functions, data are nonsense and so are the contents to be displayed.
This is anything but “observable.”
Next, essence of “observable” is what to do once it’s seen.
・Like the Shop Floor Control Option, the Gantt chart of TPiCS-X displays ○,× and △ on it, and allows you to understand what is possible to start now and to relate you to the next action.
・And as you understand the workload status of the job by looking at the workload display of the Gantt chart, you can adjust the schedule before delay in production occurs.
・Or, when stretching requests (delay information) from your suppliers are applied to the Schedule data in TPiCS-X, you can tell a problematic spot immediately and make adjustments to it since delivery dates for parts that are behind schedule against the following processes are displayed in red.
・You can adjust these schedules by dragging and dropping the Gantt chart. The result of the adjustment can automatically issue a delivery date change instruction, or you can send the Delivery Date Change data directly to the supplier by using the SCM option, and you can prevent scary contact omissions.
To constantly maintain the Schedule data in the system is as important as to always maintain the master files right.
maintain the data right in the system, to put the soul into the system, and to surely get the most out of the data. (Refer to “observable” in 2. Repetitive Production for detail as well.)
As for the problem of delay, the idea is the same as the repetitive production, too.
In order not to make something that shouldn’t happen happen, the only way is “to find a sign of delay and destroy the problem beforehand” like the “chilly hat” of safety control in factories. (Refer to “Solving the problem of delay with TPiCS-X” in 2. Repetitive Production for detail as well.)
As for the adjustments to the production schedule for the discrete production, you directly make changes to the schedule with the mouse on the Gantt chart, considering the association of the daily schedule with the previous and following processes and the workload.
We are going to think about inventory reduction by source of inventory even though it’s the discrete production.
Here are those sources:
① “Dead stock” due to miscalculation, mistakes in arrangements, and engineering changes.
②“Operating inventory” that spontaneously occurs in day-to-day production activities.
■ Reducing “dead stock.”
● Issuing instructions when needed
“Our company’s policy is not to keep inventory because we are implementing the Manufacturing Number Control and we only make as much arrangements as required.” There are many such companies but there are very few companies that hold no inventory after physical inventory at the end of the year.
Without cancel orders from customers, without engineering changes, or without erroneous arrangements, unnecessary inventory must not occur.
As long as “something you don’t want to happen” never goes away, however, it is an important answer to keep the damage to the minimum when “something you don’t want to happen” does happen. And that’s where the production control is put to the test.
In the case of the manufacturing number control, when the drawing comes out, you can reduce the risk of stock in dead storage by not making a purchase until the time has come without purchasing all by manufacturing number right away.
For TPiCS-X, the setting of “Schedule Detail creation period” works even when arranging by Mfg. No. Control, and after the mfg. no. explosion, the scheduled order issue date is calculated back from the delivery date of each part, and if it is not the time to issue the purchase order, the purchase order will not be issued. Instead, if you perform the Purchase Order Form Issuance operation every day, the Purchase Order data will be automatically created and the purchase order form will be printed when it is time to issue the purchase order.
In the case of manual work, the method of “issuing a purchase order later” causes omission of issuance, so it is inevitable to issue it all at once. Also, if the system was developed based on manual work, it may be possible to issue it all at once. In the case of the discrete production, however, the risk of delay in delivery by suppliers may increase when issuing orders later.
Therefore, you must consider the balance between them.
● Inventory allocation function by the system.
Setting it aside whether it’s deliberate or unwanted inventory, if there’s inventory in the process of arrangements, allocating it results in the effective utilization (less inventory) and inventory decreases.
When performing arrangement work in manual procedures, there are many things that are “accidentally” forgotten. Even if it is processed by the system, there are quite a lot of systems that have no functions of inventory allocation at all in the case of the general Manufacturing Number Control systems. Since TPiCS-X allows you to allocate inventory that has not yet been allocated before to the manufacturing numbers at the time of the next arrangement of the manufacturing numbers, you can reduce inventory.
● Reducing mistakes in arrangement work.
It is important to reduce erroneous arrangements as well in order to reduce inventory. I explained it focusing on “making it easier and faster processing” in the section of the “production for short-term delivery,” but the linkage between the Structure Information Conversion Option(CAD) and the One Item Production Option of TPiCS-X has another important effect of “reducing mistakes in arrangements.”
Needless to say, no erroneous arrangements lead to no inventory caused by them.
■ Reducing the “operating inventory.”
The operating inventory can be categorized as “inventory that inevitably occurs from coming into the factory and going out from there” or “inventory that prepares for unexpected orders.” Since “reducing inventory that inevitably occurs” and “reducing delays in production and shipping” have almost the same meaning in the case of the discrete production, I think it is unnecessary to get onto it in terms of “inventory.”
● It is necessary, as a matter of course, to “examine the necessity” or to “lessen the lot to purchase” in order to reduce “inventory that prepares for unexpected orders.” In addition, the “standardization of the parts to use” also has effect.
If the kind and quantity of inventoried parts increase, you can manage only parts and materials with f-MRP. TPiCS-X allows you to control the production with the manufacturing numbers depending on the item, to process it with f-MRP, and to set up in combination (by mixture) of the above two based on the part and the nature of the unit. And it is also possible for you to allocate something that was arranged in advance with f-MRP to the manufacturing numbers, and to arrange the shortfall with f-MRP if there is any as a result of the manufacturing number explosion. This is an efficient function when the kind and quantity of inventoried parts increase.