The Whole Polyester Chain in One Table: Typical Engineering Ranges
We collect the typical engineering ranges of the entire 100% polyester production chain — from fibre IV to the 4-point acceptance threshold — into a single reference table; every value is labelled typical/representative and tied to a standard where one exists.
A technical fabric supplier's numbers usually live scattered: IV on one TDS, dyeing temperature in an email, residual shrinkage in a lab report. This article consolidates them into one reference table — the typical engineering range of every link in the chain, from petrochemistry (PTA + MEG → PET) through spinning, texturing, knitting, HT disperse dyeing, stenter heat-setting and final inspection. The goal is to let a merchandiser read a TDS or a quote like an engineer: which figure is normal, which is anchored to a standard, and which is only a representative shop-floor practice.
One important caveat: almost every numeric range in the table is not a standard code but a typical/representative band commonly observed across the industry. Where a code number is cited (e.g. ASTM D5430), it defines a method or an acceptance rule, not a guaranteed figure. Actual values for a given lot vary with yarn, machine, recipe and target performance; binding numbers should always be read from the lot TDS and the lab report. This guide is general and educational, and contains no facility-specific capacity, ΔE or MOQ figures.
Typical engineering ranges — one reference table
| Parameter | Typical range (representative) | Note / standard |
|---|---|---|
| Fibre-grade PET intrinsic viscosity (IV) | ~0.60–0.66 dL/g | Bottle-grade ~0.76–0.85 (raised via SSP). ASTM D4603 / ISO 1628-5 |
| Esterification temperature (CP) | ~250–265 °C | PTA + MEG → BHET; continuous polymerization |
| Finisher / polycondensation | ~280–290 °C, vacuum ~1–3 mbar | Chain growth to target IV |
| TiO₂ delustrant (lustre) | ~0% bright / 0.3–0.5 semi-dull / up to ~2% full-dull | Lustre is locked in the polymer, not in dyeing |
| POY take-up speed | ~2,500–3,500 m/min | Undrawn, feedstock for DTY |
| FDY take-up speed | ~4,000–6,000 m/min | In-line drawn, low shrinkage |
| HOY/FOY take-up speed | ~5,500–6,000+ m/min | Highly oriented; ASTM D2256 / ISO 2062 (tenacity) |
| Texturing draw ratio (POY→DTY) | ~1.5–1.7 | Simultaneous draw + false-twist + heat-set |
| Texturing D/Y ratio | ~1.6–2.2 | Disc surface/yarn speed ratio; main bulk lever |
| Primary (texturing) heater | ~190–220 °C | Set/non-set chosen via a set heater ~160–180 °C |
| Intermingling (air bond) | NIM ~0–10 / SIM ~40–60 / HIM ~100–120+ knots/m | |
| PSF tow draw ratio | ~3:1–4:1 | Apparel fineness ~1.0–1.5 dpf; tenacity ~3.5–4.5 g/denier |
| Circular knit diameter / gauge | ~30–34 in (8–48) / E18–E28 (E12–E54) | Diameter/gauge GSM lever; for GSM see D3776/ISO 3801 |
| Single-jersey GSM band | ~100–240 g/m² | Set by structure + gauge + yarn + stitch length |
| Stitch (loop) length | ~2.1–2.9 mm | GSM ≈ K/(Ne × stitch length); K ≈ 12,069 is not an established standard but a published model |
| Warp-knit (tricot) speed | ≤~4,400 rpm | HKS 2-SE class (KARL MAYER); raschel ~700–850 courses/min |
| Water-jet weaving weft insertion | often >1,500 m/min | Filament-only; hydrophobic yarn is not weakened by the water jet |
| Disperse dyeing temperature (HT) | ~110–135 °C (~130) | Hydrophobic + crystalline structure; pressure ~2.5–3 bar |
| Dyeing hold time / pH | ~30–60 min / pH ~4.5–5.5 | Acetic acid/acetate buffer |
| Liquor ratio (LR) | jet ~1:8–1:12 · soft-flow ~1:5–1:8 · low-LR rope ~1:3.7–1:5 · airflow ~1:2 | Largest water/energy lever |
| Reduction clearing | ~70–80 °C | Medium/dark shades; required for fastness. ISO 105 series |
| Stenter heat-setting | ~180–210 °C (broadly 160–220), dwell ~20–60 s | PET thermo-mechanical anchor; width/shrinkage memory |
| Padder wet pick-up | ~40–70% | Chemical finish applied at the stenter entry + fixed |
| Residual shrinkage | ~3–5% (premium <3%) | Commercial spec after the compactor. AATCC 135 / ISO 6330, ISO 3759/5077 |
| 4-point acceptance threshold | ~≤40 points/100 yd² (tight 20–28) | ASTM D5430; defects 1–4 points, max 4 per linear yard |
| Lab colour tolerance | ΔE ≤ ~1.0 (multi-illuminant) | General industry target; metamerism control |
How to read the ranges
- A code (ASTM/ISO/AATCC) fixes a method or an acceptance rule — for example, ASTM D5430 defines how to count 4-point defects; the ≤40-point threshold is a typical acceptance level agreed between buyer and supplier, not a law.
- Temperature and speed bands depend on yarn type and machine series: the same single-jersey will read differently at 125 °C instead of 130 °C, or at E28 instead of E24. It is the centre of the band, not a single number, that is 'typical'.
- Some constants (e.g. K ≈ 12,069 in the GSM model) are published model coefficients, not universal standards; weight is always tuned on the machine via stitch length and measured on the TDS.
- The only binding number is always the lot TDS and the lab report; this table sets an expectation frame, it does not commit a lot.
This article is deliberately a reference index; the physics and chemistry behind each row are covered in the focused guides in the Knowledge Center. For IV and its tenacity/pilling signature, see the 'Intrinsic Viscosity (IV)' guide; for the speed regime, the 'POY, FDY, HOY' and melt-spinning guides; for D/Y and set/non-set, the 'False-Twist Texturing' guide; for the 130 °C disperse logic and HT chemistry, the 'Why Polyester Is Dyed at 130 °C' and disperse-dyeing guides; for reduction clearing and fastness, the 'Reductive Clearing' guide; for the stenter and shrinkage, the 'Stenter / Heat-Setting' and 'Compacting & Residual Shrinkage' guides; for weight and gauge, the 'Weight Map' and 'Gauge, Stitch Length and GSM' guides; for the 4-point and lab tests, the 'Knit Quality Testing' and '4-Point System' guides.