# Line balancing

Line balancing is a production strategy that allows more effective management of production line. In line balancing, managers and engineers strive for configuration of each production line segment that won't create bottleneck. Productivity of each low-productive segment should be improved by reorganization, investments or training. Results of optimization are sometimes documented as good manufacturing practices.

Line balancing allows companies to optimally use resources, including employees, reduce stocks between production line segments, and finally implement just in time concept. Therefore, line balancing doesn't necessarily improve productivity of whole line, but it always reduces costs and improves efficiency.

Assembly line balancing is one of the challenges arising during the development of the technological process. It's very complicated task included in the NP-complete classes. Moreover, this grup consists of many calculation problems. Its actual value of complexity and significant cost reduction connected with their optimization still make them examined in terms of practical algorithms. It contains planning, compression, combination, and sequencing. The development of the alorithm makes production line balancing more universal (J.Żurek, M.Pastwa, M.Wiśniewski 2013, p.61).

## The line balancing problem (LBP)

The LBP can be presented in the following way: taking into consideration series of tasks with specific features such as different length and limitation of priority. It means that precondition of some tasks is making one or more tasks and defining the cycle time - how the tasks should be spread out on the assembly line in the certain way so that:

1. no workstation needs more time than a cycle
2. the priority restrictions are respected (E.Falkenauer, A.Delchambre 2002, p.1).

## Types of simple assembly line balancing

"Depending on the product, assembly line balancing can be in form of one of the three types of tasks described below:

1. SALBP-1[4] – minimisation of the m number of stations at a given pro-duction rate c:min{m|(m,c)is feasible for a given c production rate},
2. SALBP-2[3] – minimisation of the c line production rate with a given number of stations: {c|(m,c) is feasible for the m number of stations},
3. SALBP-E – maximisation of the E line effectiveness, that is minimisation of the product of $$m\cdot c$$, max{ $$t_{sum}$$ / $$(m\cdot c)$$ | (m,c) is feasible for possible m and c vaues}." (J.Żurek, M.Pastwa, M.Wiśniewski 2013, p.65).

## Classification of assembly line balancing(ALB) problems

There are several categories of the assembly line balancing problems. They can be classified on the basis of:

1. the amount of models which were produced on the production line
2. the character of the performed tasks' time (probabilistic or deterministic)
3. the flow character (straight-type or U-type).

We define assembly system of a single model when it comes to only one model produced on a production line. If not, we talk about multi-model assembly system which, as a name says concerns not only a single model. As mantioned above performed tasks' time can be deterministic or probabilistic. Deterministic time may occur in a situation when tasks are being made by using all advanced tools and devices by highly qualified employees (P. Sivasankaran, P. Shahabudeen 2014, p.1667).

## References

Author: Karolina Korbut