Apparel Manufacturing Systems

1 Make Through System It is the traditional method of manufacture in which an operator makes right through one garment at a time. The advantages and disadvantages of a make through system are shown in Table 1. The advantages of the Make Through The disadvantages of the Make Through System System are: are: 1. Quick throughput time. 2. Easy to supervise.

1. Low productivity. 2. High labour cost. 3. Only very experienced operators can be used.

4. It is a system only suitable in couture and sample making. Table 1 - Advantages and disadvantages of Make Through System.Conventional Bundle System With this system, sewing machines are arranged in lines. The work flows from the central (store) area to the first machine, from the first machine back to the store, and then on to the next machine, and so forth.

A distributor stationed at the store is responsible for receiving and dispatching the work. The work in progress is in the form of bundles. These bundles may be put on to a tray, a box, or a bag, or the garment parts may be wrapped and tied. The conventional bundle system was widely used in garment factories in Hong Kong during the 1950s.At that time, the level of managerial skill was not as high as it is today.

The system is still used in certain places where there are frequent changes in garment style but a low level of managerial skill. Figure 1 - A conventional bundle system. GMP Handout 2005 - Manufacturing Systems Source: ApparelKey. com 2 The Clump System Another system that has the same characteristics as the conventional bundle system is the 'clump' system as shown in Figure 2.

In Figure 2, a worker collects a clump of materials from the worktable and carries out the first operation. After he has completed his part of the work, he returns it to the able. A worker for the second operation then continues the work and so on. The process is ' collection - work - return' continues until the whole garment has been assembled. Figure 2 - Another example of a conventional bundle system - the clump system.

The advantages and disadvantages of Conventional Bundle System The advantages of the conventional bundle system The disadvantages of conventional bundle system are: are: 1. It requires excessive handling of the materials 1. The system is flexible, as it can cope with by the operators, as they have to carry their work frequent style changes. ack to the central inventory.

2. Worker absenteeism does not cause any major problems, as the controller can control the amount 2. It is difficult to control the inventory. of work received and dispatched. 3.

The system is easy to operate and supervise. 3. It is difficult to see the work in progress at the various stages of manufacture. 4. This system may encourage individual workers 4. Engineering of work places is difficult because to work faster, as they constantly have to return machines are arranged in the limited capacity.

their own work to the central inventory. . It is easier to obtain a uniform level of quality, as 5. High level of work-in-progress. the controller can check the quality control.

6. Large storage space is required to cope with the large volume of work-in-progress. GMP Handout 2005 - Manufacturing Systems Source: ApparelKey. com 3 Progressive Bundle System With the progressive bundle system, the sewing operations are laid out in sequence.

Each operator receives a bundle, does his work, reties the bundle and passes it to the next operator. Figure 3 shows a schematic view of the progressive bundle system.There is usually a storage facility such as rack, bin or table for storing the inter-process work between each operation. The work is routed by means of tickets. Any imbalance in production can be corrected by using utility workers. This system is the most widely used system in the garment industry today.

It is used in shirt factories, jeans factories, jacket factories, etc. Figure 3 - A progressive bundle system. The advantages and disadvantages of Progressive Bundle System The advantages of the progressive bundle system The disadvantages of progressive bundle system are: are: 1. High productivity. . Machine investment costs are highy.

2. The system is not very adaptable for short-run 2. A high level of labor utilization can be achieved. production and frequent style changes, as these require rearrangement of the workstations. 3.

A uniformly high standard of work can be 3. It involves high handling costs for bundle achieved. handling and transportation. 4.

Training time and costs can be reduced. 5. Semi-skilled labor can be used. 6.

Individual performance can be monitored and incentives offered. 4. It requires a high level of work in progress and therefore a high capital commitment. . It requires a high level of management skill to arrange the workflow and decide on the number of operators for each operation.

GMP Handout 2005 - Manufacturing Systems Source: ApparelKey. com 4 Flexible Flow System It is similar as the progressive bundle system, shown in Figure 4. The main feature of this system is that a section of sewing operators, each with a supply of work in a rack at the side, work at an engineered work place. The machines are laid out in such a way that a flow of work can be planned using the correct number of operators in sequence.

In Figure 4, two styles of garment are being made at one time. For style A garments, the work distributed after operation 1 can be distributed to the two operators performing operation 2. On Completion, the work from both workers is then sent to operator 3. After operation 3, the work is continued by the two operators performing operation 4 and so on. Style B progresses in more or less the same way. One important point to notice is that when a new style is to be loaded on to the system, the number of operators needed for each operation must be planned in detail to ensure a balanced output.

The number of operators for an operation should be proportionate to the time needed for that operation. Detailed planning ensures that if the production run on a style is short, only a few operators are allocated to that style. Figure 4 - Flexible flow system. The advantages and disadvantages of Flexible Flow System The advantages of the flexible flow system are: 1.

High productivity. The disadvantages of flexible flow system are: 1. Machine investment costs progressive bundle system. are less than 2.

The system is adaptable for short-run production 2. A high level of labor utilization can be achieved. nd frequent style changes, as these do not require rearrangement of the workstations. 3.

A uniformly high standard of work can be 3. It involves high handling costs for bundle handling achieved. and transportation. 4.

Semi-skilled labor can be used. 4. It requires a high level of work in progress and therefore a high capital commitment. 5. It requires a high level of management skill to 5. Individual performance can be monitored and arrange the work flow and decide on the number of incentives offered.

operators for each operations. GMP Handout 2005 - Manufacturing Systems Source: ApparelKey. om 5 Straight Line System With this system, the manufacturing process is broken down into several operations, which take the same time to complete. Figure 5 shows an example of a straightline system. Groups of operators are required to handle only individual garments. The garment parts (in trays) pass from one operator to the next, until the garment has been completely made up by one group of operators.

The central distribution unit may be a fixed table, which must be wide enough for the type and style of garment being assembled and long enough to accommodate the required number of operations.Alternatively, the distribution unit may be a conveyor belt, as shown in Figure 5 when a moving conveyor belt is used, its speed will be set to suit the cycle time. The straight-line system is used where production continues for six to eight weeks. In the garment industry, examples of this system can be found in factories making underwear, overalls, shirts, and certain classic garments.

Figure 5 An example of a straight line system. The advantages and disadvantages of Straight Line System The advantages of the straight line system are: The disadvantages of straight line system are: 1. The throughput time is fast and the work in 1.The system is not very flexible to style change.

progress is low. 2. Material handling time is low and there is no 2. Quality control can be difficult to achieve. back tracking of material.

3. The space required for each operator is small. 3. Absenteeism can cause problems, as the system is based on workers working within a time limit. 4. It does not require a great deal of technical 4.

Machine breakdowns and worker absenteeism supervision. or lateness may disrupt the workflow. 5. Shading control can be improved.

5. The opportunities to engineer work places are limited and it is difficult to introduce specialization. . The system requires a high investment in machinery, as it is necessary to duplicate several different types of machines. 7. A high standard of work measurement is necessary and high pre-production skills are required.

GMP Handout 2005 - Manufacturing Systems Source: ApparelKey. com 6 Synchro Flow System Another system having similar characteristics to the straight-line system is the 'Synchro flow' system, shown in Figure 6. With this system, garment parts of the same size and color are processed separately. Different garment parts can be processed simultaneously for assembling.

You can see from Figure 6 that the main body of the garment goes down a central line. At the seam time, collars, sleeves, cuffs, pockets, etc. , from other lines also go down a central line. The different garment parts are then processed together to form completed garments. Figure 6 - A synchro flow system. The advantages and disadvantages of Synchro Flow System The advantages of the synchro flow system are: The disadvantages of synchro flow system are: 1.

Absenteeism can cause problems, as the 1. The throughput time is fast and the work in system is based on workers working within a time progress is low. limit. . Material handling time is low and there is no 2.

Machine breakdowns and worker absenteeism back tracking of material. or lateness may disrupt the workflow. 3. A high standard of work measurement is 3.

It does not require a great deal of technical necessary and high pre-production skills are supervision. required. GMP Handout 2005 - Manufacturing Systems Source: ApparelKey. com 7 Unit Production System A unit production system (UPS) is a computer-controlled production line. It is a type of line layout that uses an overhead transport system to move individual units from workstation to work station for assembly.All the parts for a single garment are advanced through the production line together by means of a hanging carrier that travels along an overhead conveyor.

Production operations are completed without removing the parts from the carrier. Automated materials handling replaces the traditional system of bundling, tying and untying, and manually moving garment parts. Electronic data can be collected from workstations, which provides payroll and inventory data, immediate tracking of styles, and costing and performance data for prompt decision. Figure 7 - Unit Production System using computerized selector conveyors.

Source: A. J. Chuter, Introduction to clothing production management, 1995 The advantages and disadvantages of Unit Production System The advantages of the unit production system are: The disadvantages of unit production system are: 1. The system is very flexible and complied with 1. Investment of the system is high. work meansurement.

2. The system has little work-in-progress. 2. A central place may be needed for quality control.

3. Small orders are not economical for using this 3. Fast through put time can be achieved because system because high preparation works is needed of the lower WIP of the system. or plant layout and line balancing. 4. Low WIP leads to space saving.

5. Application of Eton system reduces the handling time. 6. High quality of garments can be made. GMP Handout 2005 - Manufacturing Systems Source: ApparelKey.

com 8 Modular Manufacturing System Modular manufacturing groups operators into teams, or modules. The team works on one/a few garment at a time instead of a bundle of garments. The operators stand /sit at their stations and rotate to different machines as they work, becoming familiar with multiple steps in producing the garment.They also inspect their team's own work, catching and correcting mistakes as soon as they happen.

Early experiments with modular manufacturing show that, besides inspiring teamwork and improving morale, it also enhances quality and reduces worker turnover. To make a garment using modular manufacturing or the unit production, the through put time is reduced of producing a garment. Figure 8 - Modular Manufacturing System. The advantages and disadvantages of Modular Manufacturing System The advantages of the modular manufacturing The disadvantages system are: system are: 1.

One operator can handle more than one task. f modular manufacturing 1. Multi skillful and very skillful labors are needed. 2. The system is very flexible and permits better 2.

Success of the system needs highly cooperation line balancing. of the team. 3. Fast through put time, lower WIP, small batch size can be achieved. 4.

Less floor space is required. 5. More teamwork spirit is allowed, which creates a healthier working environment and improves quality. 6. Since the system is more quick response to the fashion change, which helps to develop fashion garment capability.

GMP Handout 2005 - Manufacturing Systems Source: ApparelKey. com