Many of the carpets manufactured across the world
are pile weave or knotted weave. Pile weave rugs or pile weave carpets
(also referred as knotted pile carpets or knotted pile rugs) are
manufactured with knots on them. That is to say that the pile weave or
the knotted weave is technique of producing rugs and carpets by creating
knots. The method involves the tyeing of yarn around two neighboring
warp strands which results in the creation of the knots. Knot is created
in every row after which one or more strands of weft are passed through
a complete set of warp strands. The knots are adjusted by beating them
with a comb. A pile weave rug contains between 25 to over 1,000 knots
per square inch.
Knots in the rugs and the carpets differ from region to region. Some of
the popular knots that are prevalent in the rug and the carpet world are
Persian Knots, Turkish Knots, Spanish Knots, double Knots, Tibetan Knots
and so on. For weaving either horizontal or vertical looms are used. It
is at the bottom where the weaving process starts and gradually moves
upwards as the horizontal rows of knots and wefts are added.

A weaver who has been in this sector for a longer time can accomplish
more than 8000 Knots per day. In the mid of every row with Knots one or
more wefts are placed to secure the Knots. This task is achieved by set
of smaller and simple tools like a knife with a hook, a pair of scissors
and a heavy comb, made of wood and metal. These smaller equipments are
used to beat the the knots and weft in a row.
In pile weave rugs and carpets, focus is on knot density. It is the
knot density that determines the strength and the durability of the
carpets. Once the weaving is over, the carpet is segregated from the
loom. Finally, the trimming of the pile takes place with the help of the
pair of scissors and the fringes are secured and the sides are made
stable. The knot count depends on the types of pattern used. For
example, in intricate and curvilinear patterns, higher knot count is
required whereas open, stylized design requires less number of knot
count.