Defination: Fabric defect is nothing but a undesirable fault in the fabric which deteriorate the quality fabric and make it inferior.
Warp Way Defects
As it is known that in the case of woven fabric there are two sets of yarn which are interlaced with each other ; direction those sets of yarn are known as warp and weft. The yarns in the fabric which are running along the length are called as warp ends and the defects in direction the defects caused by the warp are called as warp way defects. So, let’s have a look at fabric defects causes and remedies.
Crack between stripes
A crack is seen along the length of the fabric between the stripes woven with different weaves.
- Differences in wrap release due to uneven beam surface.
- The difference in crimp relationship of ends grouped in separate dents in the reed and in weaves.
- Avoid uneven build of beam surface by a proper system of denting at the sizing machine.
- Ensure that denting at weaving is such that ends of the two weaves are not separated by a reed dent.
More than one end working in a heald eye without the adjacent end missing.
- Sticky ends on weavers beam.
- Wrong drawing of ends through heald
- Take precautionary measures during sizing.
- Bring the defect to the notice of the drawing operator.
- Instruct weavers and supervisors to periodically check fabric to remove double ends.
A defect in a woven fabric where wrap and weft threads do not interlace as desired.
- Broken end getting entangled with the adjacent warp ends. The breaks between reed and healds are more prone to form floats, especially when the warp loses its elasticity due to over stretching or over-backing during sizing.
- Knots with long tail ends leading to the entanglement of ends.
- Fluff with long tail ends leading to the entanglement of ends.
- Fluffs or foreign matter trapped in the shed.
- Broken heald unable to lift or lower the thread.
- A lighter type of warp stops motion pins used on the loom.
- Attend to broken ends without delay on looms equipped with warp stop motion; ensure proper functioning of the same.
- Avoid long tail ends in knots in weaving preparatory and weaving.
- Ensure cleanliness of loom.
- Take maximum possible care while blowing the looms.
- Use screens to avoid fluff flying to adjacent looms.
- Inspect the heald for wear before putting on a new beam.
- Ensure proper selection of drop pins.
Incorrect positions of ends in the fabric causing considerable damage in fabrics with woven design or stripes.
- Faulty drawing of the beam.
- Faulty drawing of broken ends by the weaver.
- Bring the defect to the notice of the drawing operator.
- Ensure periodic inspection of the fabric on a loom by the supervisory stuff.
Missing end of a missing warp thread in the fabric.
- Failure of the weaver in attending to warp breaks
- Warp stop motion not acting properly
- Missing the incidence of lappers during sizing.
- Use spare ends on loon as a substitute for the missing ends.
- Instruct the weaver to attend to warp breaks immediately.
- Discourage the weaver’s habit of waiting for the broken end of the beam to advance sufficiently for knotting.
- Inspect the drop pins while putting on a new beam and weed out the defective ones.
- Check the warp stop motion assembly.
Fine cracks appearing across the fabric between groups of warp ends, matching with a pattern of denting in the reed.
- Excessive warp tension.
- Late shed timing leading to a lack of proper tension at beat-up.
- Insufficient toughing of shade.
- Adjust the warp tension.
- Resort to early shed timing.
- Raise the backrest 12-24 mm above the front –rest level.
Individual warp thread floating over a group of weft threads. The defect is more prominent in synthetic blended warps due to static electricity generation and hairiness of these yarns.
- Soft sized beam.
- Inadequate amount of anti static agent in the size recipe.
- Improper tensioning of warp.
- Ensure proper
- Ensure proper size recipe.
- Prefer slightly higher tension on the warp.
- If necessary, introduce lease rods between the healds and the drop pins.
A warp end having a diameter larger than normal.
- Excessive count variation.
- Accidental mixed-up of counts in winding and warping.
- Piecing up of the broken end with a wrong thread during weaving.
- Avoid it.
- Conduct frequent checks to avoid a mix-up of counts.
- Inspect the thrums provided on the loom.
Stripes running in warp way direction characterized by apparent differences in shade from the adjoining portions, arising mainly as a result of variation in the amount of light transmitted and reflected from groups of threads.
- Short, medium and long-term variation in the warp and/or uneven spacing reed. Coarser count and closer spacing of ends appear lighter while finer count and wider spacing appear darker in shade than the normal portion of the finished fabric.
- A mix-up of yarns of different luster, count or blend portion.
- Faulty drawing ends, e.g. double ends, missing ends, etc.
- Variations in package and beam dyeing.
- Improve the quality of warp since normal control exercised on count variation proves inadequate to prevent streakiness.
- Check the condition of reed.
- Use all metal reed which gives better results compared to pitch-bound reeds.
- Ensure early shed timing and lower warp tension to help lessen the prominence of streaks in the fabric.
- Adopt good materials handling system with proper storage and identification of materials to avoid a mix-up of yarns.
- Bring the defect to the notice of operators.
- Take care to match the shade when mixing a freshly dyed lot with the old stock, especially in the case of synthetic and blend materials.
So, this was our post on fabric defects causes and remedies. Also read our related post – Fabric Defects – Weft Way Defects-Causes And Remedies.