Polyester filament spinning post operation
Polyester filament spinning post is post-processing jobs, including drawing twisting, twisting deformation, heat setting, winding, packaging. Newborn fiber after constant temperature and humidity balance, according to product demand, after processing, POY, UDY into FDY, DTY.
Winding wire balance
OBJECTIVE: To make the water content and oil balance between the layers of the filament layers → reduce the hairiness after the stretching and reduce the breakage, so as to relax the stress in the internal structure of the primary fiber→ uniform and stable structure → conducive to the post-stretching.
(1) The equilibrium temperature 22 ~ 28 ℃ temperature drop → elimination of internal stress prolongation, temperature rise → damage the fiber structure, winding silk aging (tensile stress increase, broken head, around the roller).
(2) Humidity (air relative humidity is 80%) Air humidity rises. Damage to the fiber structure, winding wire aging (tensile stress increases, broken head, around the roller) air humidity → winding simple surface water evaporation increases → winding Jane internal and external water is different → dyeing unevenness increased.
(3) time 6 ~ 24h (up to no more than 5 days), the same impact and temperature.
Stretching multiple will directly affect the strength of the finished product, elongation and fineness. Stretching multiple high, finished product of high strength, low elongation, small size, the general control of 3.5 to 4.2.
Higher than the glass transition temperature Tg 10 ~ 20 ℃, usually 80 ~ 90 degrees Celsius.
Generally above 800m / min.
Objective: By heat setting, internal stress can be eliminated, the tensile properties of the stability, but also allows the further crystallization of the yarn, and strengthen its physical properties. Available hot plate stereotypes, the temperature is 180 ℃.
Elastic position control parameters and process cards
YS (Yarn Speed)
33H, FK6 II, FK6y-1ooo and other models are based on the speed of FR2, that is, speed, expressed in m/min.
DR =FR2 speed ( rotation rate) /FR1 speed ( rotation rate)
By stretching, false twisting combined with the processing method can be divided into two kinds of external tensile deformation and internal tensile deformation.
(1) External Tensile Deformation Stretching and false twisting are done in two areas on the same equipment, stretching and false twisting first. As the stretching occurs in the false twisting zone, it is called external stretching method.
(2) Tensile deformation within the law Stretching and false twisting in the same equipment in two regions to complete, this processing method is called the pull.
At present, the application of external tensile deformation method less, most manufacturers to improve the efficiency of the introduction of equipment are generally used within the tensile deformation method.
VR or D/Y
VR = surface speed of the loop of the false twist wrapper / surface speed of the FR2 roller (YS)
D / Y = surface speed of the false twister friction disc / surface speed of the FR2 roller (YS)
The function of VR (D / Y) ensures the false twisting effect of DTY, so it has certain curly and fluffy, D / Y and
VR determines the twisting number of DTY, VR (D / Y) is large, the greater the false twisting, the greater the crimp force, the more detailed and more curling, the more pleasing the appearance.
Therefore, the appearance, density, bristles and tight spots of DTY can be controlled through it, but within a certain range, the influence on the strength, elongation, crimp rate and curl stability of the yarn is less affected. In addition, VR (D / Y) increased, DTY dye slightly decreased.
First hot box temperature or hot box H1 temperature
H1 temperature is also called deformation temperature, its role is: If the wire in the low temperature state of hard stretch, due to the fiber tensile stress (yield strength) higher, the monofilament surface is easy to break, the interior may also appear hollow, hair Silk and broken head. The molecular chain of polyester filament yarn needs a certain degree of activity in the case of a certain amount of heat, and its degree of activity is related to the temperature. The higher the temperature is, the greater the activity is.
Therefore, the use of fiber of this thermoplastic, under the conditions of a certain temperature stretching, in order to make fiber deformation to be sub-divided. After the second hot box treated silk with high elasticity, crimp rate, crimp stability is poor, known as high-wire.
Cooling plate role
The function of the cooling plate is to cure the plastic deformation of the filament. Since the temperature of the filament after passing through the first hot box is high and the rigidity is insufficient, the filament must be cooled to below 80 ° C by the cooling plate so as to have sufficient rigidity , To ensure the normal twisting.
Cooling effect from the speed, POY oil performance and oil content, length of the cooling plate, the workshop ambient temperature, ventilation, climate and other factors are closely related.
Second hot box or lower hot box H2
H2 temperature is also called the setting temperature. Its function is that the textured yarn is in a low tension state in the second hot box, and the curled wire ring produced by false twisting has a chance of shrinking freely. Crimp weakness of the wire ring will disappear due to shrinkage, deformation of the wire crimp performance decreases.
But through the stereotypes heating can further eliminate the internal stress, leaving the curl more solid, dimensional stability becomes better, the residual torque decreases. Coupled with the further improvement of crystallization, boiling water shrinkage decreased. Deformed silk also changed from high-elastic state to low-state, known as the low-stretch wire.
The second overfeed OF2
OF2= (FR2 surface velocity -FR3 surface velocity) /FR2 surface velocity *100%
In second hot box silk has certain size shrinkage, it is associated with OF2 OF2, who is high, DTY is closer to the relaxed state of the heat setting, wire contraction rate is high, the stress relaxation more thoroughly, DTY on the volume shrinkage decreased more;
But when the OF3 is too large, the residual torque will be high. If the open wire network, OF2 control requires less than conventional wire to wire in the FR2, and the nozzle is not filament as well, and consider the customer requirements and the degree of the network so as to grasp the unwinding performance.
The third overfeed OF3
OF3 mainly controls the winding tension of the wire to ensure that the ingot has a certain volume, molding and hardness, and can also regulate the amount of oil. The adjustment process, to consider the package size and unwinding requirements.
The purpose of DTY oil is to ensure that the silk has good smoothness, collection and antistatic property. Winding and unwinding performance of DTY wire which can reduce friction coefficient and oiling rate spindle is more good, in order to meet the requirement of weaving.
The principle and function of the network
(1) when the network principle in the wire wire in the nozzle, by transverse impact of air jet and vertical wire, wire and eddy current parallel, so that each filament entanglement and vibration, so silk is constantly opening, interlacing, entanglement, thus forming the entanglements. Due to the different velocity of the fluid in different regions and the influence of speed, periodic network spacing and network node are formed.
(2) the role of the network can be saved in weaving and silk, twisting, sizing, sizing process, also free. It can greatly improve the yarn unwinding speed, reduce the breakage rate, enhance the cohesive force of monofilament multifilament, to weave smoothly and shorten the machining process. At the same time, the fabric has a certain sense of shape, and it is not easy to pilling.
Calculation of the time and theoretical output of the collaterals
Doffing time n roll quality (g) *10000*N]/ actual size (dtex) * *100% speed.
N - correction coefficient in the formula, generally about 1.02
The daily yield of single ingot theory =1*YS*60*24* (dtex) /10000*1000*N (kg)
N - correction coefficient in the formula, taking about 1.02.
The theoretical daily output of the whole machine =YS*60*24* *M/10000*1000*N (kg)
N - correction coefficient in the formula, taking about 1.02; M the machine efficiency
Process card (M type)
111dtex/72fDTY process card see table 2-7