Line Balancing Definition

Definition of Line Balancing

It is a production line in the sewing line where fabrics material moves from one work station to another continuously at an average rate. In an assembly line on the sewing line there are several main problems such as: work station imbalance, interruption of the flow of bottleneck resulting in the buildup of work in process material (WIP) in the work station. Line balancing or cross-assembly balance is the balance of job placement process at each work station per operation so that the target of production speed can be fulfilled.

Production Line Balancing

The balance of job placement in the production depends on several conditions:

• The size of material to be made is the size of fabrics garment material to be produced, whether large, medium or small parts.
• The amount of material demand as a precedence takes place smooth cross-assembly. If the amount of material supplied is reduced, the balance across the assembly will be disrupted.
• The shape of the engine layout and cross-assembly area, whether it is straight line, U-line or O-line.
• The difficulty level of the sewing process for each work station is difficult, medium or easy.
• Skill of each sewing line operator in operating the sewing process, in this case demanded the similarity and balance of the skill level of the operator so that no material or garment parts collected in one work station.

To know the level of effectiveness across the assembly used 2 indicators that must be considered are line efficiency (LE), obtained from the average amount of efficiency per work station, hourly or per day and the second indicator is smoothness index (SI) is an index indicating the smoothness of a balance across the assembly.

Production Line balancing
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Some steps must be taken to ensure that the cross-assembly balance in the sewing line goes well, like perform a detailed operating breakdown of each sewing operation, implementation can be done during the pilot sample process takes place, so that when the mass production process is done, the detail of the operation has been obtained, record the SMV standard time of each operation based on time study results, analyzes each track efficiency (LE) based on the most optimal SI and try to draw a line balancing study graph.

Terms used in Line Balancing

There are several terms that are commonly used in line balancing. they are :

Precedence diagram 

Precedence diagram is used before stepping on completion using path equilibrium method. Precedence diagram is actually a graphical representation of the sequence of work operations, as well as reliance on other work operations whose purpose is to facilitate control and planning related activities in it. As for the marks used in precedence diagrams, such as circle symbol with letter or number in it to facilitate the original identification of an operation process, arrows indicate the dependence and sequence of the operation process, etc.

Assemble product

Assemble Product is a product that passes the work sequence, that the station, every work station provides a certain process until it finishes being the final product on the final assembly.

Idle time

Where the operator or worker waits to perform the work process or the operation activities which will be done next, this part of 7 waste.

Balance delay

Is a measure of the inefficiency of the trajectory resulting from actual idling time caused by poor allocations between work stations.

Work efficiency

Work station efficiency is the ratio between the operating time of each work station and the operating time of the largest work station.

Line Efficiency

Is the ratio of the total time of the work station divided by the cycle multiplied by the number of work stations or number of work station efficiency divided by number of work station.

Line balancing is very important because it will determine other aspects in the production system for a long time. Some of the affected aspects are cost, benefits, labor, equipment, and so on.

This line balance is used to get an assembly line that meets a certain production level. Thus the line balancing must be done with the right method, so as to produce output in the form of a balance line best. The ultimate goal in line balancing is the speed maximization in each work station so that high work efficiency is achieved at each station.