**2. Spinning mill**

When yarn production is considered, regardless of the type of fiber processed, yarn production generally consists of blowroom/blending, carding, drawing, roving, and spinning steps seen in **Figure 1**, whereas an example of a spinning mill is given in **Figure 2** [11]. The same concept mentioned above is applied in yarn production. In order to produce the yarn with the aimed properties at the end, the needed adjustments have to be done starting from the very beginning of the stream until the endpoint where the yarn is obtained. In every production step there is usually more than one machine producing the same product and pouring into a common stream.

Yarn is produced on spinning frames that are ring spinning machines. Rovings come from the top to the spindles, on the way they are drafted and twisted, and the yarn forms (**Figure 3**) [12, 13]. The yarn properties, which are yarn count and yarn twist, are adjusted on the frame, but the rest of the properties listed above are the result of

**Figure 1.** *Yarn production steps [11].*

**Figure 2.** *An example of a spinning mill [11].*

*Practicing Hypothesis Tests in Textile Engineering: Spinning Mill Exercise DOI: http://dx.doi.org/10.5772/intechopen.105643*

**Figure 3.** *Rovings, spindles, yarn [12, 13].*

pressure between rollers, machine production speed, roller surfaces, delivery angles, climate, cleanness, human factor, gauge, etc. Since the yarn count is one of the adjustments done on the spinning frame, this will be considered in the rest of this chapter.
