Line balancing
Introduction
Line balancing is possible in case of mass production. There are two types of system make-to-order and make-to-system.
Make-to-order
In a Make-to-order system due dates are important. A sequencing of customer orders at various machine centers is essential. Thus high planning and control are also required.
Example job shop production.
Make-to-stock
Make-to-stock products are generally high volume consumer goods such as telephones, automobiles, wrist watches etc. the manufacture of standardized, high volume items, which involve flow shops, require control for effective production. Example mass production.
Mass production
It is concept which believes in breaking up of a task into its simplest, possible elements. These elements are then grouped as per production norms. In other words, mass production refers to a large quantity of production with standardized products having less variety.
Features of mass production system
1. It includes manufacturing of high volume standardized products.
2. There is a smooth flow of material from one work station to another work station.
3. Production time of production unit as a whole is short (i.e. because of specialization principle).
4. Closely spaced workstations reduce material handling.
5. Production planning and control is simple.
6. work-in-progress inventory is less.
7. Finished goods inventory is high.
Line balancing
It is arranging a production line so that there is an even flow of production from one work station to the next i.e. so that there are to delays at any work station that will leave the next work station with idle time. Line balancing is also defined as “the appointment of sequential work activities into work stations in order to gain a high utilization of labour and equipment and therefore minimize idle time”.
Balancing may be achieved by rearrangement of the work stations or by adding machines and workers at some of the stations so that, all operations take about the same amount of time. Assembly line is represented below in the form of a precedence diagram.
A precedence diagram specifies the order or sequence in which the activities must be performed. Each circle is a node, and the number inside each circle identifies particular operation. The number outside circle represents duration of operation. Arrow represents directions of flow of operation.
Determination of cycle time
When the amount of output units required per period (period may be hour, shift, day, week, etc.) is specified and the available time per period is given (i.e. number of working hours per shift, no of shifts per day, no of working days per week etc.) then,
Cycle time (CT) =available time per period
Outputs units required per period
Cycle time is the time interval at which, completed products leave the production line, assembly line.
Analysis of the line balancing problems
The procedure involves the following steps:
1. Balancing the assembly line in such manner so that production is completed in planned cycle.
Cycle time (CT) =available time per period
Outputs units required per period
2. The whole network is subdivided into several sub network without violating precedence relationship.
3. Operations are allocated to each station without exceeding the cycle time.
4. This ensures production of specified volume of products or items using assembly line.
5. at interval equal to cycle time, a completed assembly will be released from assembly line.
When the available work time at any station exceeds that, which can be done by one worker. Additional workers must be added at that work station. The key to efficient line balancing is to group activities or tasks in such a way that, the work times at the work station are at or slightly less than the cycle time or a multiple of cycle time. If more than one worker is required in any work station.
Objectives of assembly line balancing
The main objective of assembly line balancing is to subdivided the network into several sub networks (stations) without violating the precedence relationship and allocating operation to each station without exceeding the cycle time i.e. the sum of the times of operation allocated to each station should not exceed the cycle time.
While allocating operations to each station, the precedence relationship must be maintained. If these are followed then we can ensure production of the specified volume of products or items using the assembly line. At an interval equal to the cycle time, a completed assembly will be released from the assembly line.
Benefits of line balancing
o Minimization of number of work station.
o Maximization the balancing efficiency.
o Specialization.
o High volume.
o Division of labour.
o Efficiency of work.
Conclusion
For high volume mass or continuous production a line layout is preferred. In this, the equipments are laid out according to the sequence of operations that must be performed on the raw material to convert it into the finished product. Such a line layout is preferred in most of the assembling operations where a number of components have to be put together to produce the final product. This is called assembly line.
Introduction
Line balancing is possible in case of mass production. There are two types of system make-to-order and make-to-system.
Make-to-order
In a Make-to-order system due dates are important. A sequencing of customer orders at various machine centers is essential. Thus high planning and control are also required.
Example job shop production.
Make-to-stock
Make-to-stock products are generally high volume consumer goods such as telephones, automobiles, wrist watches etc. the manufacture of standardized, high volume items, which involve flow shops, require control for effective production. Example mass production.
Mass production
It is concept which believes in breaking up of a task into its simplest, possible elements. These elements are then grouped as per production norms. In other words, mass production refers to a large quantity of production with standardized products having less variety.
Features of mass production system
1. It includes manufacturing of high volume standardized products.
2. There is a smooth flow of material from one work station to another work station.
3. Production time of production unit as a whole is short (i.e. because of specialization principle).
4. Closely spaced workstations reduce material handling.
5. Production planning and control is simple.
6. work-in-progress inventory is less.
7. Finished goods inventory is high.
Line balancing
It is arranging a production line so that there is an even flow of production from one work station to the next i.e. so that there are to delays at any work station that will leave the next work station with idle time. Line balancing is also defined as “the appointment of sequential work activities into work stations in order to gain a high utilization of labour and equipment and therefore minimize idle time”.
Balancing may be achieved by rearrangement of the work stations or by adding machines and workers at some of the stations so that, all operations take about the same amount of time. Assembly line is represented below in the form of a precedence diagram.
A precedence diagram specifies the order or sequence in which the activities must be performed. Each circle is a node, and the number inside each circle identifies particular operation. The number outside circle represents duration of operation. Arrow represents directions of flow of operation.
Determination of cycle time
When the amount of output units required per period (period may be hour, shift, day, week, etc.) is specified and the available time per period is given (i.e. number of working hours per shift, no of shifts per day, no of working days per week etc.) then,
Cycle time (CT) =available time per period
Outputs units required per period
Cycle time is the time interval at which, completed products leave the production line, assembly line.
Analysis of the line balancing problems
The procedure involves the following steps:
1. Balancing the assembly line in such manner so that production is completed in planned cycle.
Cycle time (CT) =available time per period
Outputs units required per period
2. The whole network is subdivided into several sub network without violating precedence relationship.
3. Operations are allocated to each station without exceeding the cycle time.
4. This ensures production of specified volume of products or items using assembly line.
5. at interval equal to cycle time, a completed assembly will be released from assembly line.
When the available work time at any station exceeds that, which can be done by one worker. Additional workers must be added at that work station. The key to efficient line balancing is to group activities or tasks in such a way that, the work times at the work station are at or slightly less than the cycle time or a multiple of cycle time. If more than one worker is required in any work station.
Objectives of assembly line balancing
The main objective of assembly line balancing is to subdivided the network into several sub networks (stations) without violating the precedence relationship and allocating operation to each station without exceeding the cycle time i.e. the sum of the times of operation allocated to each station should not exceed the cycle time.
While allocating operations to each station, the precedence relationship must be maintained. If these are followed then we can ensure production of the specified volume of products or items using the assembly line. At an interval equal to the cycle time, a completed assembly will be released from the assembly line.
Benefits of line balancing
o Minimization of number of work station.
o Maximization the balancing efficiency.
o Specialization.
o High volume.
o Division of labour.
o Efficiency of work.
Conclusion
For high volume mass or continuous production a line layout is preferred. In this, the equipments are laid out according to the sequence of operations that must be performed on the raw material to convert it into the finished product. Such a line layout is preferred in most of the assembling operations where a number of components have to be put together to produce the final product. This is called assembly line.
Comments
Post a Comment