When the lean production system is mentioned, productivity comes to mind for almost every engineer, every manager, and every employee. It is said that productivity will increase with the lean production system. Most of the time, more production is what is talked about. In many of our previous articles we explained that productivity is the ratio between inputs and outputs. One of these inputs is labor. Together with the lean production system, it is possible to affect labor efficiency directly. Indeed, as we can analyze with the Yamazumi application, one of the lean production techniques, and as we will see, a large part of labor goes to non-value-adding activities. These can most often be listed as searching, motion, transport, bending, reaching, and working while turning. All of these movements arise in work areas that have not been engineered, through arrangements the employee developed alone and defined as correctly as they were able. We have all come across it: employees prefer their own work area to be wide, spacious, and such that it increases movement; they want to bring and take materials in bulk, and to produce products on a batch basis. When we look at the general reason for this, causes are identified such as engineering not having been done, the employee working according to experience, and the absence of one-piece production. For labor efficiency to be fully achieved, a Yamazumi analysis must be carried out, the ratio of the time of value-adding activities to total activity time must be determined, and the necessary improvement Kaizens must be planned. In addition to all of this, if the factors that affect labor efficiency the most are to be listed;
- Application of one-piece flow,
- Balancing the production line, with each employee taking on work suited to Takt Time,
- A suitable plant layout,
- Production according to customer demand (Takt Time) instead of trying to produce quickly
It has been established through our experience that these affect labor efficiency to a large extent. In many companies the assumption prevails that producing quickly will also improve labor efficiency, whereas for production quantities to increase it is enough that inputs increase. Efficiency does not increase as inputs increase; most of the time it does not even stay constant; on the contrary it decreases, because measures that increase speed can cause inefficiency. The most important subject to focus on is producing the goods that are sold with fewer inputs. In this way efficiency will increase as well. Because it becomes possible to produce the same product with fewer inputs.