Monday, March 19, 2018

Different Types of Fabric Defects with Images

Generally fabric defect is any abnormality in the Fabric that hinders its acceptability by the consumer. Fabric is produced with interlacement of warp and weft yarn or loop formation of yarn. During manufacturing of fabric various types of defects occur in fabric. Some fabric faults are visible and some faults are invisible. In this article I will discuss on visible faults of fabric with appropriate pictures.

Visible faults or defects in fabric may be result from the following reasons. They are:

  • Defects resulting from faulty yarn
  • Faulty weaving process
  • Incorrect dyeing and finishing processes
These faults have a visible effect on a fabric, comprising all the disproportions within the structure of the textile material that interfere with its end use. If these faults are not detected early, that is, during the manufacturing process, they can drastically affect the production process and the quality of the finished product. According to the BS 6395: 1983 standard, a fabric fault is defined as any feature within the usable width of a fabric that will downgrade the resultant garment.

Visual faults can be categorized as spinning, weaving, dyeing, and processing faults, as well as mending faults, which arise due to mistakes during the fault removal or mending process.

Here I will discuss some essential defects or faults that are appear in woven fabric.

1. Warp direction faults:
Material defects in the warp direction occur in the threads and are defined as follows:

a. Thick or thin end: A warp thread that differs in diameter from the surrounding normal ends.

Thick or thin end in fabric
Fig: Thick or thin end
b. Tight or slack end: A warp thread, or part of a warp thread, that is tighter or slacker than the surrounding normal ends.

c. Missing or broken end: The absence of a complete warp thread or part of a warp thread.

Missing or broken end on fabric
Fig: Missing or broken end
d. Broken pattern: Broken pattern is caused if warp yarn is broken when a pattern was being created during weaving.

e. Double end: A thread, or part of a thread, in the warp, which has accidentally been doubled.

f. Defective selvage: Selvage having warp yarn under high tension may cause pucker or wavy surface resulting in defective selvage. Besides, selvage may be thick and thin and may possess broken ends, temple mark, etc. Defective selvage may make the whole fabric defective and fabric finishing difficult.

Defective selvage in fabric
Fig: Defective selvage in fabric
g. Warp streak: Streak running in warp direction. Group of yarns having different dye shades may result in warp streak.
Warp streak in fabric
Fig: Warp streak
Testing for faults in the warp direction is conducted using a simple visual assessment of the imperfections in the fabric to decide which would be unacceptable in a garment. The number or faults in the fabric are then counted and their lengths are measured. Faults are tolerated if the residual cloth width satisfies the terms of the contract.

2. Weft direction faults:
Material defects in the weft direction also occur in the threads and are defined as follows:

a. Thick or thin pick: A weft thread that differs in diameter from the corresponding normal picks.

b. Tight or slack pick: A weft thread, or part of a weft thread, that is tighter or slacker than the corresponding normal picks.

Tight or slack pick on fabric
Fig: Tight or slack pick
c. Loose weft or Slough off or Snarl: When a bunch of or coil of yarn slips from the pirn during weaving then thick yarn bunches or coils appear on the fabric.
Loose weft or Slough off or Snarl
Fig: Loose weft or Slough off or Snarl
d. Missing pick: The unintentional omission of one complete pick across the full width of the cloth .
Missing pick in fabric
Fig: Missing pick
e. Broken pick: A pick that is inserted for only part of the cloth width.
Broken pick of fabric
Fig: Broken pick
f. Double pick: The thread or pieces of thread in the weft which form the woven structure but are accidentally doubled.
Double pick in fabric
Fig: Double pick
g. Trailer: Weft yarn that has been pulled inadvertently into the fabric during weaving.
Trailer on fabric
Fig: Trailer
As with the assessment of faults in the warp direction, testing for faults in the weft direction is also conducted using a simple visual assessment of the imperfections in the fabric that would be deemed unacceptable in a garment, followed by a measurement of their lengths. In this case however, no tolerance is permitted for faults detected using this method of control.

3. Stripes in the warp:
Stripes or streaks in the warp, which extend either for part of the warp direction or over its entire length and which show up as faults against the rest of the material, are considered being faults in the fabric. A visual assessment of the fabric and the measurement of the length of the stripes are sufficient tests to decide whether the imperfections would be unacceptable in a garment. Stripe faults are tolerated if the residual cloth width meets the terms of the contract.

Stripes in the warp
Fig: Stripes in the warp
4. Bars in the weft:
Bars in the weft are defined as streaks, which occur over either the full or part of the length of the weft direction and which show up against the rest of the piece. Again, a visual assessment of the imperfections is used to decide whether they would be unacceptable in a garment. The length of the bars is also measured if they occur in a sequence. No tolerance is permitted for faults detected using this method of control.

Bars in the weft
Fig: Bars in the weft
5. Knot or slubs in the warp or weft threads:
Knot or slubs in some of the weft or warp threads are considered to be faults when they are visible to an experienced person and when they spoil the appearance of the fabric. This visual assessment is sufficient to test whether the faults would be unacceptable in a garment and no tolerance is permitted for faults detected using this method of control.

Knot or slubs
Fig: Knot or slubs
6. Mixed warp and weft:
If wrong yarn is used instead of correct one, this defect appears.

7. Faulty mending and burling, tears, holes and stains:
Faults caused by mending and burling, tears, holes and stains are defined as follows:

a. Faulty mending: poor appearance of repair on the surface of the fabric.

b. Faulty burling: The presence of faults which have not been removed during burling.

Burling
Fig: Burling
c. Tears, cuts and holes: Various forms of cloth breakage.
fabric Holes
Fig: Holes
d. Stains: Areas of the cloth that have been contaminated with impurities.
Oil or other stains on fabric
Fig: Oil or other stains
e. Iron Mark: Sometimes iron marks appear in the fabric caused from rusted reed.

These types of faults are again tested using a visual assessment of the imperfections and the measurement of their length to ascertain whether they are unacceptable for use in a garment. No tolerance of these faults is permitted.

8. Fabric pieces cut in several parts:
Fabric is deemed faulty if it is cut across the whole width in two or more parts, the total being equal to the required length. Once it has been verified that the number of the separate parts together makes up the length ordered, no tolerance of this fault is permitted.

Pieces cut of fabric
Fig: Pieces cut
9. Reed marks:
Reed marks may appear due to defective reed, improper warp tension denting.

Reed marks
Fig: Reed marks
10. Rough cloth surface:
If fabric is weaving with yarn, under heavy tension or unbalanced tension then rough cloth surface appears. In the weaving time, if un-steamed yarn is used then fabric surface becomes dull.

11. Shuttle mark:
Shuttle mark appears along weft yarn and is caused due to friction with the shuttle.

12. Shading:
Shading is a common problem for dyed fabric. When color variation occurs from wrong handling of fabric.

13. Mil-dew:
If fabric is kept in wet places in store then mil-dew occurs. This is caused due to fungal invasion.

14. Cracks/ open set mark:
A higher pick density than the normal is referred to as starting mark while a lower pick density is referred to as crack. This kind of defect is mainly caused by the mechanical faults in the loom.

Cracks/ open set mark of fabric
Fig: Cracks/ open set mark
15.Tails out:
If the cutter doesn’t work properly, this fault is appears in woven fabric.

Tails out of fabric
Fig: Tails out
16. Gout or foreign matter:
Gout is a foreign matter like lint, waste, etc. that appears into the woven fabric. The main causes to produce this kind of faults for improper loom cleaning and unclean environment.

17. Temple mark:
In the light woven fabric this kind of defects are appears. When yarns are misshapen from their paths then holes are produced near the selvedges.

Temple mark on fabric
Fig: Temple mark
18. Float:
For producing float in a woven fabric, slack warp and faulty pattern card is the main reason.

Float on fabric
Fig: Float
19. Neppy:
For the excessive amount of neps in yarn, this kind of defect is found on woven fabric surface.

Neps in fabric
Fig: Neps
20. Misdraw/ wrong denting:
One or more ends are incorrectly drawn in the reed.

Misdraw/ wrong denting
Fig: Misdraw/ wrong denting
References:
  1. Design of clothing manufacturing processes by- Jelka Ger ลก ak
  2. Quality management in apparel industry by- Engr. A.J.S.M Khaled
  3. https://www.slideshare.net/azhartip1/fabric-faults-81244352
You may also like:
  1. Garment Defects Causes and Remedies
  2. Classification of Defects Zone in Apparel during Visual Inspection
  3. Seam Puckering in Apparel: Six Reasons and Preventions
  4. Sewing Defects Caused by Needles in Garments
  5. Dyeing Defects and Their Remedies