In weft knitting, the loops are formed across width of the
fabric , and each weft thread is fed , more or less at right
angles to the direction in which the fabric is produced.
It is possible to knit with only one thread or cone of yarn.
All the loops in one course are produced from the single
supply and loops are formed successive order one by one.
In this method the fabric is produced by simple up and down
movement of the needles, which is provided by the profile of
a cam system. The knitting cams are the devices which
convert the rotary machine drive into a suitable
reciprocating motion of the needles. Depending on the
design of the machine the cams are fixed, adjustable or
The knitting action can be explained as follows:
Rest position- The needle is in the rest position with the old loop in the hook of the
Tuck Position – the needle is raised and old loop is on the latch of the needle.
Clearing position – The needle is raised higher to clear the loop from the latch. The needle
reached at the top of the cam and old loop is on the stem of the needle.
Yarn Feeding Position – The needle is lowered with old loop new yarn is being fed to the
open hook of the needle.
Latch Closing position – The needle is lowered further and the old loop closes the latch
trapping the new yarn inside the hook.
Knock over position ( loop forming) – the needle is lowered still further and old loop
slides over the trapped new yarn inside the hook, forming a new loop by completing the
knitting cycle. Knitting cycle is completed with the new loop in the hook of the needle.
The knitting action
Latch Closing position 6.
Knock over position ( loop forming)
Yarn Feeding Position
Single Jersey or Plain fabric
A fabric in which the knitted loops are the same sort and meshed in the same manner
Single jersey is the simplest to knit and it can be produced either on circular or flat
machines by means of one set of needles which draw their loops to only one side of
The fabric has one appearance on the face side and a different one on the reverse. The
side on which the straight parts of the stitches appear in V formation is called the face
side ( Technical Face) and the reverse side ( Technical Back ) has twin rows of opposed
Properties Of Single Jersey
Simplest knit structure.
Face side smooth and sheen.
Back side rough and dull.
Easily ravels at both the ends.
Highly extensible in length and width.
The fabric curls towards the face at the top and bottom and towards the
back at the sides.
Laddering is very common in these fabrics.
Knitted loops in plain knit fabrics tend to distort easily under tension
which helps to give a form fitting and comfort due to property of elastic.
Purl fabric is produced by drawing face and
reverse loops at alternate courses, where odd
number of courses have all reverse loops and
even number of courses have all face loops.
It can be done on either flat or circular machine.
Several purl structures can be produced be
arranging the face and reverse loops in different
Properties Of Purl
sides of the fabric are similar in
appearance to the reverse side of the single
Ravels from both ends
Twice the thickness of the plain jersey
Rate of production is low
Almost equal extensibility in length and width
Most suitable for children’s garments, blankets
shawls and scarf etc.
A fabric in which both back and
face loops occur along the
course, but all the loops
contained with in any wale are
of the same types
A rib structure implies a knitted
fabric with face and back loops
occurring in the same courses
but not in the same wale
Rib fabric can be produced on V
– bed machine and footwear
Properties Of Rib
Face or Reversible fabric
Similar cord appearance in each side
Thicker and heavier fabric
Ravels only at end knitted last
Lies flat without curl
Excellent width way elasticity
Interlock is the name given to a double faced rib based structure
containing of two rib fabrics interlocked together.
The production of interlock fabric needs two needle beds, having long and
short needles arranged alternately on both the beds.
Two feeders are required to knit a single repeat of interlock and also cam
systems are arranged accordingly.
Properties Of Interlock
sides of the fabric have an appearance like
face side of the single jersey fabric. It is a
reversible fabric as rib one.
The structure do nor curl at edges when laid
flat on surface
Horizontal and vertical stripes can be produced
by using coloured yarns
The fabric ravels only from the end knitted last
The rate of production is low.