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WEFT KNIT FABRIC GEOMETRY PRESENTATION ON

Weft knit fabric geometry

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Page 1: Weft knit fabric geometry

WEFT KNIT FABRIC GEOMETRYPRESENTATION ON

Page 2: Weft knit fabric geometry

PRESENTED BY

• Name with ID:

• Md. Enzamul Haque (022)

• Shawan Roy (023)

• Ahmmed Sharjin Sharif (024)

• Pankaj Roy (025)

• Kohinur (027)

• Saiful Hasan Sakib (030)

• Textile 5th Intake

• Section 1

• Bangladesh University of Business & Technology

Page 3: Weft knit fabric geometry

DIMENSIONAL STABILITY

• Knitted fabric is so notorious for its tendency to change size and shape in wear and washing that to many people the phrase ‘ the dimensional stability of knitted fabrics’ will be contradiction in terms.

• The different dimensional stable states to which the knitted fabrics are imposed, and

• The loop length of yarn in the knitted loop.

Page 4: Weft knit fabric geometry

DIMENSIONAL CHARACTERISTICS

Page 5: Weft knit fabric geometry

DIMENSIONAL CHARACTERISTICS

Page 6: Weft knit fabric geometry

DIMENSIONAL CHARACTERISTICS

Constants for geometry of plain worsted knitted fabrics at different stable states (imperial unit)

Page 7: Weft knit fabric geometry

DIMENSIONAL CHARACTERISTICS

Constants for geometry of plain worsted knitted fabrics at different stable states (SI unit)

Page 8: Weft knit fabric geometry

AREAL DENSITY

Page 9: Weft knit fabric geometry

FABRIC COVER

Page 10: Weft knit fabric geometry

TIGHTNESS FACTOR

Page 11: Weft knit fabric geometry

SPIRALITY

• Spirality is dimensional distortion in circular plain knitted fabric.

• The lengthwise rows of stitches, called wales or needle lines, should occupy a truly vertical line in the fabric & should always be at right angles to the cross-wise course of stitches.

• This perpendicularity of wales to the courses is frequently, not the case & many times the wales may skew to the right or left forming an angle, which appears in the form of a twilled surface.

• This geometrical defect has termed spirality of knitting in circular fabrics.

• The following fig. shows the fabrics with normal loop position & with spirality having wales skewness.

Page 12: Weft knit fabric geometry

THEORY OF SPIRALITY

Page 13: Weft knit fabric geometry

THEORY OF SPIRALITY

Page 14: Weft knit fabric geometry

THEORY OF SPIRALITY

• The above relationship shows that the angle of spirality depends on

• 1.Number of feeders of the machine

• 2.Shape of the loop in a particular state of relaxation and

• 3.Number of active needles in the machine which depends on machine gauge and diameter

Page 15: Weft knit fabric geometry

MEASUREMENT OF SPIRALITY