I felt to contribute to this forum which has given me so much knowledge, ideas and information that helped me to solve the problems. I have worked extensively in Sap system of metal & steel industries. So I am posting a document based on real time implementation experience to map the heat treatment process. All of your suggestion & feedback will give me motivation to improve. So please post.
Heat treatment is an engineering process in metal & steel products whereby materials undergo with a series of temperature zone for a certain time to alter the physical properties and sometime chemical properties too. Mostly its metallurgical but also used in Glass & plastic product. Process involves use of heating & cooling to achieve the desired result such as hardness, tensile strength, uniformity in grain size, normalizing etc. Process also used for internal stress relieving, improve aging, quenching, annealing, tempering etc. In fact heat treatment is an essential important part of steel manufacturing process which itself is a specialized subject in Engineering. I will not discuss more into the technical feature of the process. My interest part here is how the process is being mapped in Sap with least manual intervention.
Engg Process – I will describe with reference e to steel industry where I have spent good number of years. The concerned company has many business units and manufacturing plants across the globe under one Sap system.
Heat treatment is used in many phases of a steel product. The complete process takes at least 1 day till 7-10 days!
- Product comes out of continuous casting mill or hot slab mill from electric arc furnace and goes for immediate cooling. This has to be heat treated before hot rolling
- After hot rolling, steel goes for normal air cooling process in general. But if the product is quenched with coolant and then going for cold rolling, it has to be softened. So it has to go for heat treatment
- After cold rolling, material becomes very hard. So if the next process is to make some soft products like duct & box it has to go for softening
- In plastic & glass industries, products goes for heat treatment to relieve stress and/or gather enough hardness depending on the end use
So basically it’s the intermediate material (may be semi-finished or finished as per Sap material type) which will be kept in the heating furnace. Once the heating cycle is finished it will come out for next process.
Mapping in Sap – We had mapped the process in 2 different ways which basically due to business requirement. In one process, the stock can be visible and monitored as compared to the other.
Process 1 – As soon as there is a GR from the production order it has to go for HT process immediately. This was controlled by a special control key. After the GR, order with this kind of control key will be stored in a custom Z table with HT status as blank without automatic goods movement. We used an enhancement of goods movement to update the table. If the process is to do automatic GR, then enhancement of order confirmation to be used. If a 3rd party execution system is used, this can be managed through Idoc posting. Even can be managed better with a custom confirmation cockpit (module pool) where this can be combined with many other requirements of shop floor. This can be managed without a custom table and status, but purpose of Z table is to show in a report with status for monitoring & controlling purpose as the heat treatment cycle can take 1-10 days. This cycle duration can be entered in Wait time field of routing of the product
Create a custom program which will collect all such records from Z table with blank HT status and call function module of goods movement Bapi_goodsmvt_create to do a 344 movement to block the stock. Reason for blocking is not to use for next process until the material comes out of HT. In many business process, blocked stocks are not considered for general use. In that case when MRP is run, system will create procurement proposal if there is a dependent requirement because the blocked stock will be failed in availability check. But in reality any procurement action on this requirement will be excess. To ease out this problem in the same custom program, after blocking the stock a firmed planned order with a different number series for same material, same qty, same str location with run date as starting date is created. So when MRP will run, system will not create any proposal which basically due to deficit of stock. At the same time this planned order can not be converted to PR, PO or production order. This is done with a BADi of planned order
If full ware house is implemented, the system will create a posting change notice when stock is blocked. This has to be addressed in warehouse management process like creating & confirming a transfer order wrt the PCN else it will create a –ve in ware house bin. This too can be incorporated in same custom program
The end date of planned order and HT process is start date+no of hours maintained in wait time field of routing and is updated in Z table. Also give a new status in the respective field as “material in HT”.
Once the HT process is over, again a custom program will run to unblock the stock with 343 movement and delete the planned order and update with a new status like “HT done”. This is available in unrestricted stock for next process or consumption.
These custom programs can be scheduled in background to avoid manual intervention.
This is a snapshot of the process what we mapped. There are something more into this with a custom program like user can do retreatment, force out before completion, goods issue to next production order, change the time and date etc
Process 2 – This is simpler than above, but stock cannot be monitored. Used in production process where it’s an intermediate product for next process.
The method is again through a different control key and with a new order type. But here material has a BOM of recursive nature and a different routing and a production version. After heat treatment material goes for tremendous physical property changes. So if the business is OK with a different material code after the heat treatment then just a simple BOM and routing will replace above recursive BOM & version. As in case of process 1, as soon as there is a GR it will update the custom table. A custom program will collect such records from the Z table and create a production order and consume the stock (which is under heat treatment) into the production order. The start date and finish date will be the run date & run date with wait time. When the HT is finished , a program will pick such records and update the Z table and do a confirmation of the parent order with goods receipt. Another benefit of this process is we can capture the activity cost of heat treatment in the production order.