Presented by ▪ Name with ID: – Shawan Roy (023) – Ahmmed Sharjin Sharif (024) – Pankaj Roy (025) – Kohinur (027) ▪ Textile 5th Intake ▪ Section 1 ▪ Bangladesh University of Business & Technology
What is fabric? ▪ Manufactured assembly of interlacing or interloping fibers, filaments, and/or yarns having substantial surface (planar) area in relation to its thickness, and adequate mechanical strength to give it a cohesive structure. ▪ Most fabrics are knitted or woven, but some are produced by non- woven processes such as braiding, felting, and twisting. ▪ We are generally using weaving and knitting to make fabric.
What is knitting and knit fabric? ▪ Knitting is a method by which thread or yarn is used to create a cloth. ▪ Knitted fabric consists of a number of consecutive rows of loops, called stitches. ▪ As each row progresses, a new loop is pulled through an existing loop. ▪ The active stitches are held on a needle until another loop can be passed through them. ▪ This process eventually results in a fabric, often used for blankets or garments. ▪ Fabrics made from only one set of yarns, all running in the same direction. Some knits have their yarns running along the length of the fabric, while others have their yarns running across the width of the fabric. ▪ Knit fabrics are held together by looping the yarns around each other.
Types of knitting ▪ There are two types of knitting – Weft knitting – Warp knitting ▪ Weft knitting: Weft knitting is a method of fabric forming in which loops are formed in a horizontal way from a single yarn & intermeshing of loops takes place in a circular & flat from on across wise basis. ▪ Warp knitting: Warp knitting is a method of fabric forming in which the loops are formed in a vertical way along the length of fabric from each warp yarn & intermeshing of loops takes place in a flat from of length wise basis.
Classification of weft knitting machine ▪ According to the frame design & needle bed arrangement. – Circular knitting machine – Flat knitting machine
Classification of weft knitting machine ▪ According to the no. of needle bed. – Single jersey circular knitting machine – Double jersey circular knitting machine
Classification of weft knitting machine ▪ According to the end product of the weft knitting machine. – Fabric machine – Garments length machine
Classification of weft knitting machine ▪ According to the basic structure of the weft knitting – Plan or single jersey circular knitting machine – Rib flat or circular knitting machine – Interlock flat or circular knitting machine – Purl or link-link flat or circular knitting machine
Classification of weft knitting machine ▪ According to the type of needle use. – Knitting machine equipped with latch needle ▪ Circular knitting machine – One needle bed (Single jersey knitting machine) – Two needle bed (Rib or interlock knitting machine) – Double (Purl knitting machine) ▪ Flatbed knitting machine – One needle bed – Two needle bed (V-bed flat knitting machine) – Knitting machine equipped with spring breaded needle ▪ Circular knitting machine ▪ Straight bar frame
Feature of single jersey circular knitting machine ▪ Single jersey circular knitting machine has normally rotating (clockwise) cylindrical one set of needle bed. ▪ Generally latch needles are used. ▪ Generally machine needles gauge is 24. It can be various from 10 to 36 for producing finer or coarser fabric. ▪ For Single Jersey machine, holding down sinker are used, one between every needle space. ▪ Latch needle cylinder & sinker ring revolve through the stationary knitting cam. ▪ For single jersey machine, sinker trick ring is simply & directly attached to the outside top of needle cylinder. ▪ Stationary yarn feeders are situated at regular intervals around the circumference of the rotating cylinder.
Feature of rib circular knitting machine ▪ In rib circular knitting machine, there are two needle bed. One set of needles are mounted on a vertical cylinder & other set of needles are mounted on horizontal dial. ▪ The cylinder and dial needles are rib of gaiting (the dial needles are midway between the cylinder needles). ▪ Both cylinder & dial needle bed should have two types of needle (short & long needles). ▪ Generally needle gauge is 18.
Feature of interlock circular knitting machine ▪ In interlock circular knitting machine, there are two needle bed. One set of needles are mounted on a vertical cylinder & other set of needles are mounted on horizontal dial. ▪ The cylinder and dial needles are interlock of gaiting (the dial needles are face to face between the cylinder needles). ▪ Both cylinder & dial needle bed should have two types of needle (short & long needles). ▪ Generally needle gauge is 20.
Main parts of knitting machine & function ▪ Needle – Needle is a tiny hocked elements used for loop formation. – Needle used for knitting are three types ▪ Latch needle ▪ Spring bearded needle ▪ Compound needle – Function: ▪ To feed yarn. ▪ Loop formation. ▪ To hold the old loop.
Main parts of knitting machine & function ▪ Cam (knit, tuck, miss) – Cam converts the rotary machine drive into suitable reciprocating action for the needles or other elements – Each needle action is obtained by means of cams acting on the needle bed – Three types of cam. (knit, tuck, miss) – Help to produce knit, tuck & miss loop.
Main parts of knitting machine & function ▪ Sinker – Sinker is a thin metal plate which is placed at right angle between the adjoining needles. – Sinker are tree types ▪ Holding down ▪ Loop-pulling ▪ Knock-over – Sinker is used in single jersey circular knitting machine. – Function: ▪ Loop formation. ▪ Holding down. ▪ Knock over the surface. Where its upper surface or belly supports the old loop as the new loop is down through it.
Main parts of knitting machine & function ▪ Dial – Dial is a upper steel needle bed used in double knit machine. – In the groves of dial the needles are mounted horizontally & are also to move radially in & out by their dial cam sinker used here. – Dial is used in double jersey (rib or interlock) circular knitting machine
Main parts of knitting machine & function ▪ Creel – To hold the cone holder. ▪ Cone holder – To hold the package. ▪ Plastic tube – To pass the yarn. ▪ Positive feeder – To storage the yarn. – To pass the specific amount of yarn by driving unit. ▪ Storage unit – To storage the yarn in storing unit.
Main parts of knitting machine & function ▪ Indicator light – To indicate any problem of machine. ▪ Magnetic type tensioner – To create tension in feed yarn ▪ Cylinder – To hold the needle. ▪ Feeder – To feed the yarn to needle ▪ Cam box – To hold the cam.
Main parts of knitting machine & function ▪ Sinker ring – To hold the sinker. ▪ Fabric spreader – To change the circular to flat shape of fabric. ▪ Fabric take down roller – To take down the fabric. ▪ Sensor – To identify the breakage of yarn. ▪ Dust removing fan – To remove the dust. ▪ Needle detector – To identify the needle breakage.
Main parts of knitting machine & function ▪ VDQ (Variable diameter for quality) pulley – To control the GSM. – It gives motion to the positive feeder – Diameter of VDQ ↑ ↔ Speed of Tooth belt ↑ ↔ Speed of yarn feeder ↑ ↔ Loop Length ↑ ↔ GSM ↓ – Diameter of VDQ ↓ ↔ Speed of Tooth belt ↓ ↔ Speed of yarn feeder ↓ ↔ Loop Length ↓ ↔ GSM ↑ ▪ QAP (Quality Adjustable pulley) pulley – To adjust tooth belt tension. – To adjust the quality of fabric.
Main parts of knitting machine & function ▪ Toothed belt – To transfer the motion from VDQ pulley to positive feeder ▪ Motor – To produce the motion the machine. ▪ Lubricating system – To pass the lubricating oil in the machine.
Main parts of knitting machine & function ▪ Sensor – To identify the breakage of yarn. ▪ Cam for sinker – To more the sinker is machine. ▪ Yarn guide – To guide the yarn.