POY, FDY, HOY: The Filament Spinning Line and Its Speed Regime
The machine chain that turns PET melt into filament — from spin beam to high-speed winder — and how take-up speed alone separates POY, FDY and HOY. With real OEM series and typical ranges. The three regimes are separated by ISO 2060 (linear density) and ISO 2062 / ASTM D2256 (tenacity).
4 sections 6 terms 5 sources ~4 min
The entire character of a polyester fabric begins on the spinning line, where molten PET is drawn into fine filaments. This line is a machine chain whose sequence is almost universal: heated spin beam → metering (spin) pump → spin pack and spinneret → quench → spin finish → godets → high-speed winder. Yarn from this same chain can be POY, FDY or HOY; the essential difference is not the machine but the take-up speed regime. How the polymer chemistry (PET, IV) arrives at this melt is covered in our pet-polymer-iv guide, and the physics of how take-up speed sets molecular orientation is covered in melt-spinning-poy-fdy; here the focus is the machine and the line itself.
Along the line: from spin beam to winder
Molten PET is distributed from the heated spin beam to each spinning position. At every position a metering pump pushes the melt into the spin pack at a constant, measured throughput — this pump is the critical organ that governs count (dtex) consistency. Inside the pack the melt is filtered and forced through a spinneret of thousands of capillaries, forming a filament bundle. The hot filaments solidify immediately in the quench zone; spin finish (yarn oil) is then applied to control static and friction. The filaments wrap onto godets and finally form the package on the high-speed winder. The final godet speed sets the take-up speed, and that is precisely what determines the yarn class.
- POY (partially oriented yarn): take-up speed typically ~2,500–3,500 m/min. The filament is not drawn on the line; it is a partially oriented, high-elongation intermediate, and is almost always feedstock for DTY texturing.
- FDY (fully drawn yarn): typically ~4,000–6,000 m/min. The drawing step is integrated into the line (drawn between heated godets), so the yarn emerges low-shrinkage and dimensionally stable; it is used directly in knitting and weaving.
- HOY/FOY (highly/fully oriented yarn): typically ~5,500–6,000+ m/min. The high take-up speed produces meaningful orientation even without drawing; it is a more niche regime.
Why this speed ladder yields low orientation in POY and dimensional stability in FDY — that is, the relationship between molecular orientation and take-up speed — is treated in melt-spinning-poy-fdy. How POY becomes bulky, stretchy DTY is the subject of dty-textured-yarn.
Real OEMs and series
In filament spinning machinery the global reference is Oerlikon Barmag (Germany). The WINGS platform integrates the take-up godets directly into the winder, simplifying the line layout, with typically ~30% energy savings reported; WINGS POY and WINGS FDY configurations are offered with different position/end counts. Barmag’s EvoQuench radial (inward) quench uses markedly less process air than cross-flow quench — representatively on the order of ~60–80% less — especially for microfilament; the specifics of microfilament spinning are in microfilament-science. The premium alternative is TMT Machinery (Japan): the ORCA POY lines and the ATi-MANTA-II FDY with its I-Box draw zone are well-known series. The spinneret design that sets the cross-section geometry — round, trilobal, hollow — is covered in fiber-cross-section.
Positions and ends: the capacity lever
A spinning machine’s output scales largely with its position and end count. POY machines typically carry 10–24 ends per position, while FDY counts are usually lower (≤~32, because the draw godets need room). Spinneret capillaries are typically ~0.2–0.4 mm and capillary throughput on the order of ~0.5–5 g/min; spinneret/pack temperature runs in the ~235–295 °C range. On FDY lines the first godet (GR1) is typically ~65–90 °C and the draw godet ~108–130 °C. All of these figures are typical/representative ranges; actual values vary with product, OEM and line configuration.
POY · FDY · HOY compared
| Property | POY | FDY | HOY/FOY |
|---|---|---|---|
| Typical take-up speed | ~2,500–3,500 m/min | ~4,000–6,000 m/min | ~5,500–6,000+ m/min |
| Drawing on the line | No (undrawn) | Yes (in-line integrated draw) | No (high speed orients) |
| Orientation / shrinkage | Partially oriented, high elongation | Highly oriented, low shrinkage | Highly oriented |
| Typical use | Feedstock for DTY texturing | Direct knitting/weaving; stable | Niche; selected applications |
| Typical ends/position | ~10–24 | ≤~32 | Variable |
In short: the machine chain of the filament spinning line is fixed; what differentiates the output is take-up speed. POY is an intermediate for DTY; FDY, drawn on the line, gives a stable, directly usable yarn; HOY holds a more niche position through the orientation that high speed alone provides. To understand why a yarn shows a particular hand, stretch and dimensional behaviour, knowing which regime the line ran is the first step.
Frequently asked questions
What separates POY, FDY and HOY?
The machine chain is almost identical; what separates them is the WINDING SPEED. POY is wound at typically 2,500–3,500 m/min and is NOT drawn in line — it is a partially oriented, high-elongation intermediate. FDY is wound at 4,000–6,000 m/min and, with integrated in-line drawing, yields a stable yarn that can be used directly. HOY runs at roughly 5,500–6,000+ m/min, where orientation comes not from drawing but from THE SPEED ITSELF.
What scales the capacity of a spinning line?
The number of positions and ends. POY machines typically carry 10–24 ends per position, while in FDY that number is generally lower — because in-line drawing demands a heated godet group for every end. The global reference OEM is Oerlikon Barmag; its WINGS platform integrates the draw godets directly into the winder and simplifies the line layout. The resulting yarn is separated by fineness to ISO 2060 and by tenacity to ISO 2062 / ASTM D2256.