Inspection Loop During Production
Let’s get to the basics:
Inspection process in apparel industry Part II
In my last article, I explained the inspection processes adopted in apparel factories before the start of actual production. This 2nd part of the article highlights the inspection processes during the course of actual bulk-production.
The famous book ‘Managing Quality in Apparel Industry’ by P.V. Mehta very rightly states that “The day is long past when apparel manufacturers can depend solely on 100% final inspection at the end of production line. The quality cannot be “inspected into” a garment after it has been made; instead, quality should be “manufactured into” a garment at every step and checked repeatedly during production.”
In this stage, pieces are inspected during various stages of the bulk production, before final assembly of the garment takes place. The quality of garment if inspected close to the manufacturing point lowers the rework costs of quality, by reducing the amount of rework required, as the source of the problem is identified as early as possible. In-process inspection aids in the identification of the workmanship insufficiencies, and equipment malfunctions.
It should be conducted in every production section; spreading, cutting, ticketing and bundling, sewing and pressing or finishing.
The requirement to detect the error at the source gives strength to the need for inline inspection. After the initial inspection has identified the discrepancies, key manufacturing points are inspected for conformance to the specifications, like stitches per inch, seam allowance, stitch types, machine types and work aids usage methods, etc. the critical operations are identified for the style by the technical team and products on those operations are inspected.
The basis of defining critical operations is as follows:
- Complexity of performing the operation
For example, the armhole of a jacket has to be stitched with extra caution since it is difficult to handle bulk fabric at curved edges. Hence, it becomes a critical operation.
- The Garment Zone – the particular component falls in.
- Ease of reparability of the operation
For example, if pocket placement in case of trousers is not checked at the right stage, it becomes difficult to rectify it because it involves ripping waistband, side seam, etc.
- Need of installing Critical Inspection Station positioning a QC before & after certain operations to avoid extensive rework
For example, in case of production of trousers in a line, typical checkpoints are generally installed at certain positions such as:
For checking puckering, Pocket up/down, facing up/down etc.
For checking back dart, welt pockets up/down, etc.
- Side Seam:
For checking side seam margin, in seam margin, etc.
For checking waistband belt closing, width and notch to notch matching, loops placement, hook & eye attachment etc.
- End line inspection
Overall check like waistband up/down, label attachments, bottom hem overlock etc.
Similarly in case of a shirt:
For checking pocket placement, placket, puckering, etc.
For checking yoke, label attachment, etc.
For checking shoulder & sleeve attachment, collar, buttonholes, etc.
Here is an example of a typical daily in-line report:
(Daily In-Line Inspection Report Template)
End-line inspection refers to the manufacturer’s installed inspection station at the end of the production line to inspect the final garments. In this stage, often a 100% inspection criterion is used.
In end line inspection, the sample size can be determined based on the batch or the lot size, and the sample’s acceptance criteria are based on the AQL* level as required by the buyer. The garments are inspected of their conformance to the size and appearance specifications, where the defects identified are stickered, to make the rejected pieces identification easy on the floor.
The observations from this inspection are recorded into an End-Line Inspection report, and the production line supervisor is thus notified about the defects, who, in turn, gets the rework done on those pieces. Once the defects are rectified, the pieces are re-inspected for quality.
Here is an example of a typical daily end-line report:
(Daily End-Line Inspection Report Template)
These are the inspection processes followed during the manufacturing of a garment. The last and final stage of a typical inspection process includes final random inspection after the garment has been manufactured. Watch out this space for an elaborate explanation on FRI.
To read more such articles, do visit www.stitchdiary.com or follow ThreadSol on slideshare.
*AQL: Acceptable quality level (AQL) is defined by ANSI/ISO/ASQC A3534 as follows: “When a continuing series of lots is considered, a quality level which for purposes of sampling inspection is the limit of satisfactory process average.”