Prioritisation and Analysis of Faults in Shirt Production by the A3 Technique

The A3 problem-solving technique, which is the core of the lean management system, provides a guide to find answers to the questions of “who, what, when?” for dealing with the current situation, finding the root causes of the issues, and finding various solutions to these root causes as a process and a mindset. While in the traditional management approach, simple solutions are brought to problems encountered to save the day. Within the A3 technique, permanent solutions are obtained through more profound insight into the problem or systems created to prevent problems by taking pre-measures and precautions. This thinking approach ensures that everyone in the organisation proceeds in the same direction by gaining the support and understanding of the individuals in the organisation. It is widely known that today’s product life curves have been shortened, and product diversity has increased. Lean thinking has become even more critical to cope with today’s competitive environment. In order to ensure the permanence of the practices, this philosophy must become a part of corporate culture in the managerial sense.

This study aims to solve the problems that occur in apparel production with the aid of Pareto charts and A3 reporting philosophy, as mentioned above, and to organise the process in the best way. The following studies can be given as examples of comparative studies carried out until today.

In a study conducted by Şeker in 2019, the advantageous and disadvantageous aspects of the A3 reporting technique compared to the Obeya and SMED techniques were discussed within a theoretical-based approach [1]. In a book review conducted by Morgan and Liker (2006), the importance of the A3 reporting technique in the Toyota production system was mentioned. According to the study, the essential features were cited as follows: the A3 technique gets to the bottom of identified faults and eliminates problems completely [2]. Akay, Tiryaki, and Çelebi discussed lubrication and packaging processes in the metal industry. In this study, the faults encountered in lubrication and packaging processes were handled and evaluated through the A3 technique [3]. In a study conducted by Kara in 2018, the problems encountered in an aircraft assembly area were discussed. Pareto analysis was used to prioritise the problems identified [4]. In a master’s thesis undertaken by Gülsün in 2006, the ERP-enterprise resource planning installation in companies operating at the international level was examined, and problems encountered in the installation of this system were analysed statistically [5]. In a study conducted by Çakırkaya and Acar in 2016, the significance of the faults encountered in a production line was determined by Pareto charts, which is one of the statistical process control techniques [6]. In a study by Ala and İkiz in 2014, Pareto charts was used again in determining the prioritisation of fabric defects that occurred during the weaving production process [7].

In this study, the production lines of a clothing company were studied, and faults encountered during the production were determined. Analyses were conducted with the help of Pareto charts considering the frequencies of these faults and the faults that needed prior consideration were identified. The root causes of the most common fault were determined within the A3 technique. Based on these analyses, a manufacturing apparatus was developed to make it easier to eliminate the fault mentioned in the processes. The effects of these apparatuses on the manufacturing processes were examined in terms of time, quality and cost. Moreover, necessary investigations were conducted accordingly.

Faults detected resulting from the examinations, the explanation of them, and their effects are shown in the following Table 1.

The faults encountered are handled on a line basis. These faults are sorted within the machine and human factors, shown in the following figure in terms of daily checked quantity, number of working days, the total number of controls, total number of faults encountered, and common fault types.

While determining the faults to be examined, the above data were taken into consideration, and detailed analysis of the lines were conducted accordingly. These analyses and the fault rates are explained in detail between figures 1–6 with related data. 6 different production lines were examined for 22 days, and, as a result, the faults and fault frequencies indicated in Table 2 were obtained.

Fig. 1

Fig. 2

Fig. 3

Fig. 4

Fig. 5

Fig. 6

As can be seen from the Pareto analysis (Figure 7), the collar tip form (28,21%), stain (25,08), cuff form (12,99%) and button (10,02) faults have a 76,3% fault ratio among 17 fault classes. As a result of the investigations on shirt production, it was found that if 4 of the 17 faults were prevented only, 76,3% of the total faults could have been reduced.

Fig. 7

In this study, the collar tip form fault, which is the most common and most important one, is discussed. The collar tip form fault, which constitutes 28,21% of the total faults, means that the collar is not symmetrical, the tips not sharpened properly, or the shadings that have occurred in the inside seam allowance are not cut properly. If the collar, which is the first point of attention of a shirt, is not produced symmetrically and adequately, it means a great loss in terms of quality. Figure 8 highlights an example of some poor quality related to the collar part.

Fig. 8

The A3 reporting technique was used to prevent this fault. In this context, the A3 report was obtained from the application of the technique to the collar tip fault, shown in ANNEX-1.

Based on the analyses stated above, to eliminate the collar tip fault by the A3 technique, a collar cutting and everting apparatus was developed to obtain more standardised and symmetrical collars. By utilising this apparatus, the seam allowances of the collar tips could be cut more uniformly and symmetrically to prepare the collar in a shorter time. Details of this apparatus are shown in ANNEX-1. Examples of the collar tips formed by cutting and everting with the apparatus developed are shown in Figure 9 below.

Fig. 9

3.1

Application of A3 Technique to the Problem

Resulting from the investigations carried out in a shirt manufacturing company, the faults and their frequencies were recorded. The Pareto analysis revealed that the most common fault among them was the “collar tip form”. Accordingly, the A3 technique was used to eliminate it. Data obtained from this technique are as follows.

Roadmap of Current Status

In this technique, firstly, the collar preparation and everting process applied within the current system is defined. A map of the current process was prepared. The following steps were performed within the current system for collar preparation and everting.

• Preparation of collar patterns

• Placing the pattern on the spreading plan (CAD)

• Drawing and cutting the pattern

• Arrival of the cut pieces to the production line

• Marking the collar pieces and interlining process

• Assembling the pieces

• Cutting the seam allowance surpluses

• Everting the collar and sharpening the collar ends with a sharp tool such as a pencil, cloth scissors, etc.

• Symmetry control of the collar and giving it the final form

Process Times of the Current Situation

The calculated standard times for collar preparation and everting process are stated as follows through the examinations of these steps.

Based on the time studies conducted, 14 seconds was spent on even cutting of the seam allowance parts, while the collar form and turning took 29.1 seconds. The standard time of the collar preparation and turning was calculated as 65.2 seconds in total.

Table 3

	Collar Forming Records
	Manually
	Taking a piece - putting under the needle		Sewing		Cutting (the seam allowance)		Turn inside out - Forming the edges (manually) (2 Edges)		Putting the piece away - taking another one
	Sec	R	Sec	R	Sec	R	Sec	R	Sec	R
Sample-1	3,8	100	10,2	100	13	105	30,4	95	1	100
Sample-2	4,2	95	11	95	15	90	31	90	1	100
Sample-3	5	95	10,6	100	14,5	100	29,4	100	2	90
Sample-4	3,66	100	10,8	100	13,4	100	29	100	2,5	90
Sample-5	3	105	12	90	13,9	100	30	100	2	90
Sample-6	3,7	100	10,7	100	14	100	30,7	95	2	90
Sample-7	2,9	110	11	100	14	100	29,8	100	1	100
Sample-8	3,5	100	11	100	13,6	105	30	95	1	100
Sample-9	3,7	100	10,2	100	15	90	32	90	1	100
Sample-10	3,1	100	10	95	14,8	105	29,1	100	1	100
Averages	3,7	100,5	10,8	98,0	14	1	30,1	96,5	1,5	96,0
Basic Time= Avg Time × Avg Rating 100	3,7		10,5		14,0		29,1		1,4
Total Basic Time	58,7
Relaxation Allowance (%4)	2,35
Unavoidable Delays (%7)	4,11
STANDARD TIME (sec)	65,2

Definition of the Problem

Activities that cause poor quality in the current process are listed as follows:

• Asymmetry of the collar ends

• Collar end forms not being at the desired sharpness

• Everting process and preparing the collar end forms evenly should be accelerated depending on the workflow.

• Since the seam allowance of the collar parts are not cut properly, this may cause shading or seam problems.

Analyses

Root-cause analyses, shown in the following diagram, were carried out in order to eliminate the processes that lead to poor quality.

Fig. 10

Goals

Based on the root cause analyses and the A3 technique, the desired developments, in other words, the goals, are as stated below:

• Standardisation of the operation

• Eliminating the problem of shading in the collar edges

• Smoothing the sharpness in the collar tips

• Increasing productivity

• Developing an apparatus suitable for the process that can be used by operators

• Using the workforce more effectively

Precautions (Improvements)

Precautions (improvements) recommended to the company are as follows;

• First of all, the operator should be checking the cut collar parts in terms of the cut quality.

• After sewing the collar parts, the operator should cut the remaining seam excess with the developed apparatus (Figure 9).

• The operator should perform the reversal of the collar with the “collar cutting and everting apparatus” developed within this study.

• The operator should check the symmetry of the collar tips in a quicker way.

Collar Cutting and Everting Apparatus

The apparatus developed consists of two different parts: the first enables to cut the seam allowances clearly (Figure 11), and the second helps operators to evert the collars evenly (Figure 12). This apparatus can be placed on different parts of the machine table in accordance with the hand side of the operator most used. The apparatus developed is shown below in Figure 11.

Fig. 11

Fig. 12

Improved Time Plan

Time study data of the process steps belonging to the collar everting and giving the desired form with the apparatus developed are shown in Table 4.

Table 4

	Collar Forming Records
	With the Apparatus
	Taking a piece - putting under the needle		Sewing		Cutting (the seam allowance)		Turn inside out - Forming the edges (with the apparatus) (2 Edges)		Putting the piece away - taking another one
	Sec	R	Sec	R	Sec	R	Sec	R	Sec	R
Sample-1	3,6	95	11	100	8,1	105	18,4	100	1,2	100
Sample-2	3,2	100	11,2	110	7,5	105	18	100	1	100
Sample-3	3,5	100	10,8	105	9	100	17,5	100	1,5	95
Sample-4	3,6	95	10,9	105	7,3	100	17,7	95	1	100
Sample-5	3,4	95	11,5	100	8,7	90	18,2	100	1,5	95
Sample-6	3,4	100	11	100	9	90	18	100	1,4	95
Sample-7	2,6	115	10,7	100	9	100	17,9	95	1,3	100
Sample-8	4,2	90	10,8	100	8,7	90	17	95	1,2	100
Sample-9	3,7	100	11,5	95	8,8	100	17,8	95	1,4	95
Sample-10	3,9	100	10	110	9	100	19	90	1	100
Averages	3,5	99,0	10,9	102,5	8	5	18,0	97,0	1,3	98,0
Basic Time= Avg Time × Avg Rating 100	3,5		11,2		8,3		17,4		1,2
Total Basic Time	41,7
Relaxation Allowance (%4)	1,67
Unavoidable Delays (%7)	2,92
STANDARD TIME (sec)	46,2

According to the calculations, while cutting the seam allowances of the collar tips took 8.3 seconds, the standard time for collar everting and sharpening of the tips took 17.4 seconds with the apparatus developed. The total standard time of this process was calculated as 46.2 sec.

3.2

Evaluations

As can be understood from the visuals of the collars prepared with the improved collar apparatus, it is now possible to obtain collars in a more uniform form with standard quality. Thanks to the apparatus developed, the following advantages could be gained:

• -

  The shirt collar tip form can be adequately prepared, and it is thought that the quality level can be standardised.

• -

  The asymmetry problem between the two ends of the collar forms was eliminated due to the advantage of the new apparatus. The sharpening and shadowing problem of the collar tips was prevented.

• -

  The collar everting process was realised faster and more smoothly thanks to the improved collar apparatus.

Thanks to the time studies carried out, the time spent on cutting the seam allowances after collar circumference sewing and that spent on the process of everting the collar and obtaining the sharp form at the tips of the collar were compared. Accordingly, while cutting the seam allowances at both ends of the collar took 14 seconds manually, it was completed in 8.3 seconds with the cutting apparatus developed. This apparatus shows that the process is completed in 40.7% less time. Similarly, the reversal of the collar and the sharpening of the two collar ends lasted 29.1 seconds when performed manually, and this process was completed in 17.4 seconds thanks to the collar everting apparatus developed. Owing to this apparatus, a time saving of approximately 40.2% was achieved.

Collar automats (Figure 13), which are preferred by a specific section of companies, operate only on shirts on the market, and provide superiority in terms of speed and quality in all operations performed on the collar. An image of a collar automat is shown in Figure 13.

Fig. 13

In studies and investigations carried out in companies using this automat, it was seen that while the cutting of the seam allowance of a collar and giving the desired tip form by turning takes 7.9 seconds, the standard time of collar preparation and the turning process is determined as 24.6 seconds. Another critical point is the sales price of the system, which is $2050 as the market price (25.04.2020).

In this study, firstly, faults encountered in a shirt manufacturing company and their frequencies were determined. Afterwards, these faults were listed according to their percentages and frequencies by means of Pareto Analysis. Based on the examinations carried out using A3 diagrams on the most common faults, the reasons for the poor quality of the shirt collar were determined. Accordingly, developed apparatuses were used to eliminate these reasons.

Although there is an existing collar automat currently in use in the market, investment decisions that need to be made for an automat should be well considered in today’s difficult economic conditions. A price-time comparison of the operations performed on a collar manually, with the apparatus developed and by automats available on the market, is listed as follows.

As a result of the examinations, data belonging to the three different methods were calculated, shown above (Table 5). Based on the data, the time spent on cutting the collar seam allowance was determined as the highest when the activity was performed manually. The duration of the activity performed with the apparatus developed and with the automat were close. When the collar preparation activity durations were examined in total, it can be seen that while the total time spent for the process with the automat was 24.6 seconds, this time is 87% faster than for the developed apparatus - 46.2 seconds, and 165% faster than the activity performed manually - 65.2 seconds.

In today’s demanding economic conditions, which require deep analysis of investment decisions, it is possible to achieve similar quality with the apparatus developed in this study with a cost of only $ 84, instead of investing $ 2050 only for a collar operation. Nowadays, companies are designing their production lines to produce various products instead of specialising in a single product type to keep up with the different product demands of their customers. Therefore, they may be hesitant to invest in an automat that can only be used for collar production. This study demonstrates the importance of this decision by emphasising the advantages of the apparatus developed over its rivals.

Another advantage of the apparatus developed is the possibility of adding it to the working area of each operator working with collars, given its lower costs. However, since automats are comparatively expensive, there are only 1 or 2 plants in factories.

Regarding this study’s method, A3 reporting is one of the essential methods used to address and solve the problems encountered in companies. At this point, the A3 reporting method is becoming quite useful in solving issues because it has a simple and effective nature. Since the problem-solving process needs to be continuously handled, different statistical process control techniques supporting this method will provide more concrete benefits to companies, which will be dealt with in future studies.