Most of the production systems employed in clothing factories are derived from the following manual or mechanical systems. Each production system has its own specific operational characteristics. This article discusses the features, merits and demerits of different garment production systems.
Individual system/Make through/Whole garment system
This is essentially the traditional method of production whereby one operator assembles the entire garment. In men's bespoke wear, it is not uncommon for a tailor to perform nearly every operation required to make the garment, including machining, hand work and pressing.
With this production system the operator would be given a bundle of cut work and would proceed to sew it according to his or her own method of work. Of necessity, the labour required by this system must be highly skilled and versatile, a combination which is becoming exceedingly rare and increasingly expensive.
This type of system is effective when a very large variety of garments have to be produced in extremely small quantities. A typical application would be in the sewing room of a boutique, which produces its own merchandise.
Whole Garment Production SystemThere are two types of Whole Garment Production Systems: (1) complete whole garment and (2) departmental whole garment. In the whole garment system one individual makes the entire garment from cutting the cloth to sewing and pressing the garment. The garment is ready for dispatch once the operator completes the final operation. This type of system is used in a few places, which are engaged in custom-wholesale. They are normally high priced and exclusively made for a particular customer. They are limited in number and distribution; normally about 10-20 garments are made.
The departmental whole garment system is also used by custom wholesale manufacturers as well as high price or better dress manufacturers. In the departmental whole garment system one individual does all the work with the equipment allocated to a department. For example, one person does all the cutting work in cutting department, second person does all the sewing work in sewing department, and the third person does the pressing and packing work. The workers in this system may use more than one equipment to complete their respective job.
Advantages1. This system is more effective when a very large variety of garments have to be produced in extremely small quantities.
2. In Individual piece rate system the operators will do with full involvement: To finish more pieces, to earn more money.
3. Operator will be specialised in his own working area.
4. As the pay depends upon the complication of the operation, the operator will try to finish the complicated operation also without any difficulties.
5. The Work in Progress (WIP) is reduced, at a time one cut garment to one operator and so the amount as inventory is reduced.
Disadvantages1. Highly skilled labourers are used, so the cost of labour is high.
2. The operator is more concerned on the number of pieces finished rather than the quality of work.
3. Productivity is less due to lack of specialisation.
4. For long run/bulk quantity of same style is not effective in this system.
Section or Process System - Group System This is a development of the making through system, with the difference that the operators specialise in one major component and sew it from beginning to end. For example, an operator specialising in fronts would assemble the front, set the pockets, etc and perform all the operations required to finish that particular component.
The sewing room would have a number of sections, each containing versatile operators capable of performing all the operations required for a specific component. The sections are built according to the average garment produced, and include:
º Pre-assembling (the preparation of small parts)
º Front making
º Back making
º Main assembly (closing, setting collars and sleeves, etc)
º Lining making
º Setting linings
º Finishing operations (buttonholes, blind-stitching, etc)
All in all, this is a very efficient system for producing a variety of styles in reasonable quantities. Figure 1 shows a typical layout and workflow for this type of system.
Advantages 1. As the labour of all levels, ie, semi skilled, skilled, trainee can be used in this system, the labour cost is less compared with individual system.
2. Productivity is higher compared to individual system, because of the use of special machine and all types of labour.
3. This system is very efficient for producing a variety of styles in reasonable quantities.
4. Automation and specialisation can be done.
5. Absenteeism and machine breakdown problems will not cause serious problems.
Disadvantages1. All the levels of operators are involved in the work, so the quality of garment should be strictly maintained.
2. Even though productivity is high still the highly skilled operators are required to perform simple operation within the section.
3. Group of people involved in each section and so we require more WIP, which increases the inventory cost.
4. As this is not a bundling system, there are more chances to mix up of lost, shade variation, sizes, so quality and production will be affected.
Progressive Bundle System - Batch SystemThis system is exactly what its name implies, a system whereby the garments are gradually assembled as they move through successive sub-assembly and main assembly operations in bundle form. The principles of this system are:
º The various sections are positioned according to main operation sequence, with each section having a layout according to the sequence of operations required to produce a particular component. For example, the sleeve section could contain the following sequence of operations:
1. Run stitch collar
2. Collar turn/iron
3. Collar top stitch, etc
The amount of machinery for each operation would be determined by the output required.
º A work store is positioned at the start and end of every section of these buffers is used to store work received from a preceding operation, and to hold work completed by that section.
º Due to these work stores or buffers, each section is not directly dependent on the preceding section, but can absorb slight variations in output via the stocks held within the section.
The progressive bundle system, while being somewhat cumbersome in operation and requiring large quantities of work in progress, is probably one of the most stable systems as regards output. Unless there is serious absenteeism or prolonged special machine breakdowns, most of the usual hold-ups can be absorbed because of the amounts of work in progress.
Balancing and the changeover to new styles are also somewhat simplified, due to the amount of work held in reverse. When properly managed, the progressive bundle system is versatile and efficient.
Advantages1. Labours of all levels, ie, unskilled, skilled, semi skilled labours are involved in this system where the operations are broken into small simple operation. Hence the cost of labour is very cheap.
2. Here the quantity of each component is checked during the individual operation itself, so the quality is good.
3. The components are moved in bundles from one operation to next operation, so there is less chance for confusion like, lot mix-up, shade variation, size variation, etc.
4. Specialisation and rhythm of operation increase productivity.
5. As the WIP is high in this system, this is stable system. Because of the buffer, the breakdown, absenteeism, balancing of line, change of style can be easily managed.
6. An effective production control system and quality control system can be implemented.
7. Bundle tracking is possible, so identifying and solving the problems becomes easy.
Disadvantages1. Balancing the line is difficult and this problem is solved by an efficient supervisor.
2. Proper maintenance of equipment and machinery is needed.
3. Proper planning requires for each batch and for each style, which takes a lot of time.
4. Improper planning causes labour turnover, poor quality, less production, etc.
5. Increase in WIP in each section increases the inventory cost.
6. Planned and proper layout should be made to make the system effective, ie, smooth flow of material.
7. Variety of styles & less quantity are not effective in this system.
8. Shuttle operators and utility operators needed in every batch to balance the line effectively.
Straight-line or 'Synchro' SystemAs its name suggests, this system is based on a synchronised flow of work through each stage of producing a garment. Time-synchronisation is the most important factor of this system because the flow of work cannot be synchronised if there are considerable variations in the standard times allowed for all the operations performed on the line.
For example, if one operation has a value of 1.5 minutes SAM, then all the other operations in the line must have the same, or a very close, value. The manipulation required to balance the standard time for each operator can sometimes lead to illogical combinations of whole or part operations which are not always conducive to the overall efficiency of individual operators.
Layout for full sleeve shirt - Batch System PBS - Synchro Straight Line System 
The synchro system by its very nature is rigid and particularly vulnerable to absenteeism and machine breakdowns. At all times reserve operators and machines must be available to fill the gaps. In addition, this system requires a sufficient volume of the same type of garment to keep the line in continuous operation.
Unit Production System (UPS)As a mechanical system this has been in use for many years, but a major advance was made in 1983 when computers were first used to plan, control and direct the flow of work through the system.
The essential features of this type of system are:
1. The unit of production is a single garment and not bundles.
2. The garment components are automatically transported from workstation to work station according to a pre-determined sequence.
3. The work stations are so constructed that the components are presented as close as possible to the operator's left hand in order to reduce the amount of movement required to grasp and position and component to be sewn.
The operational principles are as follows:
All the components for one garment are loaded into a carrier at a workstation specially designed for this purpose. The carrier itself is divided into sections, with each section having a quick-release clamp, which prevents the components from falling out during movement through the system. When a batch of garments has been loaded into carriers they are fed past a mechanical or electronic device, which records the number of the carrier and addresses it to its first destination. Some of the more intelligent systems address the carriers with all the destinations they will have to pass through to completion.
The loaded carriers are then fed onto the main powered line, which continually circulates between the rows of machines. This main, or head, line is connected to each workstation by junctions, which open automatically if the work on a carrier is addressed to that particular station. The carrier is directed to the left side of the operator and waits its turn along with the other carriers in the station.
When the operator has completed work on one carrier, a push button at the side of the sewing machine is pressed and this actuates a mechanism, which transports the carrier back to the main line. As one carrier leaves the station, another is automatically fed in to take its place. When the carrier leaves the station it is recorded on the data collection system, and then addressed to its next destination.
Unit Production System requires substantial investments, which are not always justified by conventional payback calculations. Apart from the measurable tangible benefits, UPS also have many intangible benefits such as a more orderly and controlled flow of work, and the ability via the control computer of simulating the production situation some time in advance. These intangibles are difficult to measure, but in themselves make a very positive contribution to the overall viability of the unit.
All things considered, unit production systems have major advantages over all the other manual and the mechanical systems used for the mass production of clothing. Most importantly, they provide a clothing factory with the capability to respond quickly to any changes, which might occur. In the fast moving fashion business, this is essential.
Advantages1. Bundle handling completely eliminated.
2. The time involved in the pick-up and disposal is reduced to minimum.
3. Output is automatically recorded, eliminates the operator to register the work.
4. The computerised systems automatically balance the work between stations.
5. Up to 40 styles can be produced simultaneously on one system.
Disadvantages1. Unit production system requires high investments.
2. The payback period of the investment takes long time.
3. Proper planning is required to be effective.
Quick Response Sewing SystemThis system was first developed in Japan to enable quick responses to be made to market changes, especially when orders for individual styles were in small lots. Each workstation is equipped with two or four machines and the operator will take the garment through the required operations, including pressing, before it is transported to the next workstation.
Quick response system layoutSome of the basic machinery is duplicated in different stations and if there is a bottleneck in one section the overload is automatically transported to other stations where operator capacity is available.
All the parts of one garment are loaded into a hanging clamp attached to the trolley and in theory, there should only be one garment at each workstation. Work is transported by a computer controlled, overhead trolley system and each station has an individual controller, which provides the operator with information on the style being worked on. This information comes from an information card, which accompanies each trolley.
A less sophisticated version of QRS uses a wheeled trolley, which contains the components for one garment and is pushed along the floor from operator to operator.
Another feature of QRS is that all the operators work in a standing position so that they can move quickly from one machine to another within their own workstation. Machine heights are adjusted accordingly and touch-pads and knee-pads controls are used instead of conventional foot pedals.
Featuresº Supervision: Freed to work with the operators.
º Labour: Of necessity the operators must be highly skilled in the operation of all the different machines in one workstation.
º Quality: In-process inspection stations are built into the line and the inspector is able to return faulty work via the system to the operator concerned.
º Productivity: This is very high because the operator handles the garment once only for a number of operations, instead of once for each operation.
º Throughput time: As there are so few garments on the line throughput time is extremely short, which is the objective of this system.
º Layout: A typical unit would have eight work stations arranges around the transport system.
There is no doubt that this type of system is one of the best answers to the garment production revolution, which is becoming more apparent every day. Fashion changes are becoming more frequent and as a consequence order lots are proportionately smaller. A production system, which enables changeovers to be made in the minimum of time is ideally suited to this new and dynamic situation.
Evaluation of Production Systems
Any production system has four primary factors, which make up the system. Processing Time + Transportation Time + Temporary Storage Time + Inspection Time = Total Production Time.
Processing time is sum total of working time of all operations involved in manufacture of a garment. Transportation time involves the time taken to transport semi-finished or finished garments from one department to another or from one operation/machine to another. Temporary storage time is time during which the garment/bundle is idle as it waits for next operation or for completion of certain parts. Inspection time is time taken for inspecting semi-finished garments for any defects during manufacturing or inspecting fully finished garments before packing.
The main aim of any production system is to achieve minimum possible total production time. This automatically reduces in-process inventory and its cost. The sub-assembly system reduces temporary storage time to zero by combining temporary storage time with transportation time.
ConclusionThe choice of best apparel production system will depend on the product and policies of the company and on the capacities of manpower. Where style changes are frequent and lot sizes small, it may be advantageous to use skilled labour who can make whole garment and use one of the whole garment system. As the lot size increases it is advisable to use section production system.
The sub-assembly system is superior to the progressive bundle system as it takes less time. That is the processing time for a garment in both system is same but sub-assembly system has less waiting or temporary storage time. However the space requirement, machinery requirement and labour costs are high for sub-assembly system.
In most cases the choice of a production system depends on the cost of the inventory-in process. Inventory-in process is the total number of garments in the production line. This consists of all garments being processed at sewing machines, under inspection and in temporary storage between operations. When material, labour, space and interest costs are high, synchronised sub-assembly system which yields the least possible in-process inventory is more suitable.
One of the aims of any production system is to make total production time as minimum as possible. This automatically reduces inventory cost to a minimum. Sub-assembly system provides many opportunities to economise on temporary storage and transportation space and time. No definite answer can be given as to which is the best, as it depends on garment style, specifications, machinery and manpower and manufacturing policies.
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