In weft weaving, it defines the two yarn systems that make up the fabric, which are located towards the width of the fabric. The weft threads are at right angles to the warp threads.
In shuttle looms; to the winding process of the weft bobbin placed in the shuttle. weft preparation It called.
What are impacted teeth?
When one or more teeth fails to grow in the correct position and is therefore held below the normal gum line, it is called an impaction. This can be complete, such as completely unerrupted (buried) third molars (wisdom teeth) or partial when just part of the tooth is visible in the mouth.
Why are impactions important?
For best function and appearance the teeth should grow in a healthy alignment. When one or more teeth is impacted, this can affect the function of that tooth but also the function and appearance of other teeth.
Whether all impactions should be treated is still controversial and your dentist and oral and maxillofacial team can explain the advantages and disadvantages or treatment for you, which is usually surgical.
On looms without shuttle; Since the wefts are fed directly from the bobbin, there is no need for the weft preparation section.
Weft winding: bobbin weft winding ve jumpsuit type scarf wrap done on machines.
Roller weft winding machines: It is used for winding thin yarns. In this system, weft yarn is wound on wooden, plastic or cardboard bobbins. As the bobbin rotates and winds the yarn, a traverse (forward-backward) movement is given to make the winding smooth. As the thread is wound on the bobbin, the thread guide slides forward. When the bobbin length reaches the desired length, the spindle rotation is stopped because the thread guide touches the mechanism that stops the spindle rotation.
Overalls weft wrapping machines: It is generally used for winding thick yarns. The yarn is wound on a spindle on the machine. There is a conical guide to give the wound yarn a taper. Spindle rotates and performs the winding operation. As the spindle rotates, the traverse bar moves back and forth, ensuring that the winding is smooth. As the bobbin is wound, the coiled part shifts to the right under the pressure of the conical element and when the bobbin reaches the desired length, the idler lowering stops the winding.
The system is different in modern weaving machines. Weft thread is thrown into the nozzle by shuttle (projectile), rapier, airjet, waterjet systems. The weft insertion amount has reached up to 600 beats per minute with these methods. The weft is unwound from the bobbin onto the cylinder. It is taken into the mouthpiece from the cylinder without impact and at a constant speed. The brake device releases or brakes the weft thread in accordance with the rhythm of the weaving machine..
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