Validation Applications in MES Systems

Validation; It covers the procedures that need to be done to prove that the method used is accurate and precise, and that it continuously performs what is expected. In other words, it is ensured that a planned production is continuously checked whether it is realized within the plan.

When working with a validated method, it is guaranteed that the process is precise, accurate, specific, consistent, valid and reliable.

Not every operation, not every new work can be done by every personnel working in the field. Some work can only be done by competent people. It is requested to be done by the person who is the expert of the work to be done. This is a validation. This ensures that the work done is precise, accurate, consistent and reliable. MES does not only do this electronically. It also forces it mechanically and stops your machines from working when something goes wrong. If it is seen that the electronically monitored work goes wrong, it prevents it from continuing further and prevents work that will not be consistent and correct.

Validation is not limited to personnel. If the barcodes of the mold and raw material LOT defined for a work order are not physically scanned, the machine is prevented from running and there is no room for any error.

Thanks to such features, quality, continuous and accurate production is realized. This is an important feature that saves companies both time and money in every respect.

Polyvalence literally means the competence of a worker or operator on a job. For example; let's consider a factory producing white goods. There are many processes in the factory. There are many machines in these processes and operators using these machines. The competence levels of these operators differ from process to process, from machine to machine. Not every operator may have the competence to use every machine. Polyvalence determines the degree of competence here.

In the polyvalence table, personnel are evaluated according to the following criteria. Separate scoring is done for each criterion. The effect of the criteria on the overall scoring is at different rates, and the points given are added to the overall scoring at the determined rates. Personnel evaluation criteria;

A scoring is made by taking into account the experience of the relevant personnel for the machine and/or work in question. For example; 20 points between 1-2 years 20 points between 2-3 years 40 points.

Here, the competence of the relevant personnel to use the equipment is checked. This scoring is done by the department responsible. The criteria considered are as follows; 

An oversight committee should be formed at this stage. This committee should include the Production Manager, Department Supervisor, Maintenance Supervisor and Quality Supervisor. Scoring is done by this committee with the following criteria;

If we need to process an example Polyvalence table, we can think like this. Let's consider some processes as follows;

- Steel Cutting

- Lathe

- CNC Machining

- Heat Treatment

Let there be one operator in each of these processes. If the operator in the steel cutting process is very good and has not made mistakes for a long time, his polyvalence is 4. This means that he is one of the most competent people in these processes and can work uncontrolled. If the operator in the lathe process is good and has not made mistakes for a long time, his polyvalence is 3 and he can work uncontrolled. If the operator in CNC Machining operation has some work to learn and is at a medium level, his/her polyvalence is 2. He/she can work in a controlled way. If the operator in the heat treatment operation has tasks to learn and is at a weak level, his/her polyvalence is 1 and he/she cannot work in any way.

Polyvalence table is the table showing the current polyvalence and target polyvalence status of the operator. Annual training plans can be made using the polyvalence table. When making a job announcement, the deficiencies are determined by using the polyvalence table and a job announcement can be made accordingly. It can be used when determining the increase rate to be given to the operator. Polyvalence table can be used when making appointments. These operations are usually carried out in the human resources department at workplaces. A sample polyvalence table; 

Validation studies in MES systems can be evaluated in two basic categories. One of them is the verification of the production process and the other is the verification of whether the consumption process is proceeding correctly, also known as validation.

When we consider the production process, of course the first validation study that comes to mind is polyvalence validation. When we say personnel competency validation, we naturally do a quality check. In addition to the quality check in the context of personnel, a quantity check can also be performed. For example, it may be a necessity for more than one operator to work at the same time in order to perform certain production operations. Serial press operations in which more than one part is produced at the same time may be an example of this situation. In such cases, not only the quality of the personnel is not enough, but it may also be desired to check whether there are enough personnel at the machine at that moment to work that work order. We already have partners with whom we carry out validation studies in this direction.

Another important topic to be validated before and during the production process, apart from manpower, is equipment control. In the field, the process starts at the beginning of production when the operator selects a work order to work on the screens of the MES system, which we call HMI or panel. Choosing the right work order is the backbone of the data collection setup. An incorrect work order selection also means incorrect evaluation of very important process elements such as cycle time, production stock, consumption stocks, planned production quantity, which is very critical as it can lead to problems such as inaccurate productivity calculation and deterioration of warehouse stock balances.

Equipment control is also a sensible validation tool in the context of correct work order selection. The equipment code foreseen to be used in the work order selected by the operator can be checked in various ways in the MES system when the operator wants to load the work order / start working. One of them is to barcode the equipment and when the operator wants to work on a work order, first of all, to have the MES system read the barcode on the equipment he/she plans to use with the help of a barcode reader and compare this equipment / mold with the equipment envisaged to be used in the work order. In case of verification, the process is ensured to continue as it should, and in the opposite case, the operator is shown the relevant warning and directed to load the correct work order.

Another method is the method that requires the MES system to communicate with the PLC system at a high level. What is meant by high level here is not a signal communication at the bit level, which we call 1 and 0, but communication between the machine and the MES system with open messages that can also be read by humans. In this way, without the need for the operator to scan the equipment barcode with a barcode reader, the correct equipment / mold and the correct work order can be checked by comparing the equipment code currently available on the relevant machine with the equipment that is envisaged to be used in the work order to be loaded. In addition to this control, in our partners, in addition to this control, it is ensured that the relevant control is made and action is taken not only during the start of work, but also when there is a Setup or mold change stop during production.

Under the consumption process heading, sub-validation examples such as stock, stock balance and lot/batch control can be considered. Here, it would be a healthy method to perform balance and lot/lot inquiries integrated with the ERP system. At the start of production or during production notification, it can be verified whether the raw materials and semi-finished products planned to be consumed are really the raw materials and semi-finished products that the operator is about to start consuming at that moment, warehouse balance checks of the relevant consumption stocks can be performed, and this control can be taken one level further and back traceability can be provided by performing consumption validation in the form of lot/lot tracking.

Make personnel entry mandatory or no production notification without personnel entry;

The work done must be guaranteed to be precise and accurate. What will guarantee that this work is correct is a parameter developed to check whether the right person is doing this work or not. Since production data is continuously collected in MES, of course, it is also digitally recorded who produced the parts produced.

A metal semi-finished product from previous downstream operations may be subjected to an annealing process in the furnace. For example, the conveyor of this furnace has an ideal flow rate of minutes/meters. In order to speed up or slow down this speed and prevent quality problems in the semi-finished product, this conveyor belt speed is constantly monitored with MES systems and it is constantly checked whether it is within the desired range or not. Thanks to this, quality problems that may arise are prevented before they occur.

Let's consider a line that counts production units with barcode. Let's say 30 seconds for this work order given a certain cycle time. We expect each product to come out between 25-35 seconds. However, in order to track the production correctly and to get the correct numbers, we ensure that the operator scans the barcode by complying with this cycle time. This system, which prevents him from accumulating barcodes and scanning them repeatedly, makes it precise and consistent to collect accurate data instantaneously.