Polyester PET Continuous Spinning-Drawing-Interlacing Process Line, Mod. 4Y, 4Y HMLS PET

Description

  1. Overview
    1. Inventory number: E-6461
    2. Polyester high tenacity – low shrinkage (HMLS) spinning – drawing – interlacing continuous process line
    3. Model 4Y
    4. Produces multifilament polyester yarn PET HMLS (high module low shrinkage)
    5. Yarn suitable for production of straps for lifting purposes, covers for trailers, and yarn for tyres
    6. Products normally obtained between two counts (550 and 1100 dtex) as unitary count, and 2200 dtex using two coupled 1100 counts
  2. General Process And Plant Description
    1. Polymer treatment integrated system: when PET suitable polymer for high tenacity yarn production is not available, a post condensation treatment is required; continuous crystalliser/dryers are implemented even on small scale PET spinning plants for FDY, but post-condensation is also required to increase I.V. to the needed value for high tenacity FDY spinning; the most suitable solution is a polymer treatment integrated system which performs all operations to reduce moisture and increase I.V. of PET chips by crystallising and drying to < 0.004% residual moisture, and immediately later, postcondensation working
    2. For production of HMLS yarn type, a continuous SSP is absolutely recommended; such continuous polymer treatment integrate system is basically a continuous crystallasing/drying system having its last drying zone simply lengthened in the direction of chip flow and fed with a separate gas stream at the appropriate temperature in order to continuously obtain similar results
    3. Spinning plant model FDY 4Y HMLS PET: dried polymer of proper viscosity is fed to the extruder hopper; the horizontal extruder is designed with a special feeding zone and an optimal L/D ratio and screw profile to achieve the highest throughput and melt uniformity; the extruder cylinder is heated by multiple heating zones, with individual temperature control which allows to set the temperature profile according to the raw material properties and product specifications; the polymer manifold and the spinning beams are temperature controlled by a Dowtherm vapour system; the spinning pumps are driven by frequency controlled synchronous motor that guarantees the best speed accuracy and yarn count uniformity; the spin-packs are bottom loaded, with filtering media to guarantees a long pack life; spinnerets are round type and each one extrudes a bundles of filaments, which are cooled inside a radial quench by means of a controlled flow of conditioned air; the quench cabinet can be (international patent) lowered to give easy access to the spinnerets for cleaning and also for pack change over
    4. After cooling, the yarn enters in a finish applicator; each draw-winding machine wind four ends; pre-tension rolls guide the yarn end to the slow duo rolls; the drawing takes place between the first duo rolls, second duo rolls and third duo rolls; a fourth set of duo rolls, which are also heated, give the yarn relaxation time for the required low shrinkage; each roll is driven by synchronous electric motors
    5. The multi induction heaters system, with dual shell draw rolls, ensure an absolutely uniform temperature profile
    6. The yarn ends are wound on bobbins with a high speed winder
  3. Design Specifications
    1. Polymer raw material: raw material specification before SSP treatment (if required): the FDY spinning plant included in the scope of supply of this offer has to be fed high viscosity PET polymer; such high viscosity PET polymer will be provided by a suitable polymer treatment integrated system
    2. Typical specifications for the incoming PET chips before treatment:
      1. Material: polyester granulate polyethylene terephthalate (amorphous)
      2. Intrinsic viscosity: 0.645 to 0.690 dl/g (with deviation range ≤ +/-0.015) [based on relative viscosity measured by test method BASF no. 3101 and using Huggins constant K’=0.35]; higher I.V. such as 0.83 is appreciated but only if this is not in combination with presence of “plasticising materials” (as for bottle grade PET chips)
      3. Melting point: ≥ 259 °C [test method: BASF no. 2301]
      4. Moisture content: ≤ 0.1% assuming chips delivered by large capacity trucks [test method: BASF no. 3201]
      5. TiO2 content: 0.05 to 0.07% [test method: BASF no. 1403]
      6. COOH end groups: ≤ 30 meq/kg [test method: BASF no. 3121]
      7. Color number (APHA): ≤ 25 [test method: BASF no. 3601]
      8. DEG content: ≤ 1.1 W/W% [test method: BASF no. 3702]
      9. Reflectance: lightness (Ry) 60 to 67%, yellowness index (Rx-Rz) 0 to 4% [test method: BASF no. 3602]
      10. Chip, fiber density: 1.39 g/cm3
      11. Bulk density: approx. 750 kg/m3
      12. Granulate size: approx. 2.5 x 3.5 x 2.5 mm (cylindrical)
      13. Specific chip number: approx. 50 chips/g
      14. Oversized chips plus undersized chips ≤ 0.2% (oversized ≥ 3 times / undersized < 0.5 times of one of the given dimensions)
    3. The polymer treatment integrate system performs necessary crystallizing, drying to less than 0.004 weight % residual moisture (required for postcondensation) and solid state postcondensation (at higher temperatures)
    4. Raw material specification after SSP treatment (if required):
      1. Moisture content: < 0.004% [test method: BASF no. 3201]
      2. Intrinsic viscosity: 0.9 to 1.1 dl/g [based on relative viscosity measured by test method BASF no. 3101 and using Huggins constant K’= 0.35]; the polymer treatment integrate system will be designed to reach values of I.V. up to 1.1 (to be confirmed after joint definition of the most suitable values of shrinkage and tenacity); depending on features of the incoming chips, FDY process conditions and actually requested yarn characteristics for the various applications, postcondensation parameters (temperature, vacuum and time cycle) will be tuned to obtain the most suitable I.V.; an intrinsic viscosity of 0.99 +/- 0.02 dl/g is assumed as reference
    5. Product and relevant specifications:
      1. Type of filament yarn: PET HM-LS-FDY for “technical” applications
      2. Final product: HM-LS-FDY
      3. Filament cross section: round
      4. Colors: none
      5. Additives: none
      6. Required bobbin length: 250 mm (core length around 300 mm)
      7. Final use(s): weaving on projectile looms, then coated with PVC plastisol paste for use as tarpaulins, truck covers, tent material, billboards signage materials, etc.
      8. Yarn counts: 550 – 2200 dtex
      9. Tenacity at breakage: 70÷72 CN/dtex (based on a filament count 5.7 dtex p.f.)
      10. Shrinkage in hot air: equal or less than 3.5% at 18