First, high-quality polypropylene (PP) resin pellets are selected
as the base material, as PP offers inherent water resistance and
durability—critical for marine and shipping use. To achieve the
yellow, blue, and white coloration, color masterbatches (concentrated pigment pellets) in the three target colors are
separately mixed with pure PP resin in precise proportions. This
ensures uniform color distribution: yellow, blue, and white
masterbatches are each blended with PP resin to create three
batches of colored PP compound, avoiding color fading or streaking
in the final rope.
The three batches of colored PP compound (yellow, blue, white) are
fed into separate extruders. Inside the extruders, the compound is
heated to a molten state (typically 180–220°C) and pushed through a
spinneret—a metal plate with hundreds of tiny holes. As the molten
PP exits the spinneret, it is rapidly cooled by air or water to
solidify into thin, continuous monofilaments (single strands) of consistent diameter. Each color (yellow, blue,
white) forms its own set of monofilaments, which are then wound
onto bobbins for subsequent processing.
To enhance the tensile strength and durability of the monofilaments
(critical for withstanding shipping and marine loads), the colored
monofilaments undergo a drawing process. The monofilaments are pulled through a series of heated rollers
at a controlled speed, stretching the fibers to align their
molecular structure. This step reduces brittleness, increases
load-bearing capacity, and ensures the monofilaments can resist
abrasion—essential for contact with ship hulls, docks, or cargo.
After drawing, the monofilaments are rewound onto larger bobbins.
Next, the drawn monofilaments of each color are grouped and twisted
into single strands:
- One strand is made entirely of yellow monofilaments,
- One strand of blue monofilaments,
- One strand of white monofilaments.
A twisting machine rotates the monofilament bundles at a specific
speed to create tight, uniform strands. The twist level is
calibrated to balance flexibility and strength—too loose, and the
strand may fray; too tight, and the rope may become rigid. Each
colored strand is wound onto a bobbin once plying is complete.
The three colored strands (yellow, blue, white) are mounted onto a stranding machine (or rope-twisting machine) in a triangular arrangement. The
machine rotates the three strands together in a consistent
direction (e.g., right-hand twist) to interlock them into a single
3-strand twisted rope. The twisting tension and speed are precisely
controlled to ensure the strands are evenly distributed, with no
gaps or uneven tightness—this guarantees the rope’s structural
stability under load. During this step, the yellow, blue, and white
strands create a distinct, visible twisted pattern.
After forming, the rope undergoes post-processing to remove any
surface imperfections (e.g., loose monofilaments) and is inspected
for quality:
- Checks include measuring diameter consistency, testing tensile
strength, verifying color uniformity, and ensuring no strand
breakage.
- Qualified ropes are then wound onto large spools or coils (in
lengths tailored to shipping/marine needs, e.g., 100m, 500m) for
storage and transportation. No additional chemical treatments are
required, as PP’s inherent properties already meet marine/shipping
standards.
- Used as mooring lines and dock lines for small to medium-sized vessels (e.g., fishing boats,
recreational yachts, small cargo ships). The 3-strand twisted
structure provides sufficient flexibility to tie secure knots
(e.g., cleat hitch, bowline), while PP’s water resistance prevents
rot or weight gain from seawater. The yellow-blue-white coloration
enhances visibility, making the rope easy to spot in low-light or
choppy water—reducing the risk of accidental tripping on decks or
tangling with other equipment.
- Ideal for securing cargo on ships, barges, or docks. It is used to tie down containers,
pallets, or loose goods (e.g., machinery parts, construction
materials) during transit. PP’s high tensile strength resists
shifting caused by wave motion or ship vibration, while the twisted
structure ensures the rope stays tight without slipping. The
lightweight nature of PP also makes it easy for crew members to
handle and adjust, even when securing heavy loads.
- Applied in recreational marine activities, such as:
- Tying inflatable water toys (e.g., tubes, rafts) to boats;
- Setting up temporary swimming area markers (the bright
yellow-blue-white colors improve visibility for swimmers and other
vessels);
- Securing fenders (boat bumpers) to hulls to prevent damage during
docking.
Its non-abrasive surface also avoids scratching boat paint or
inflatable materials.
- Used for light-duty towing of small vessels (e.g., dinghies, jet skis) behind larger boats in
calm coastal waters or harbors. The 3-strand design’s strength
handles the tow load, while PP’s elasticity absorbs minor shocks
from wave action—reducing strain on both the towing and towed
vessels. The coloration ensures the rope is visible to nearby
boats, minimizing collision risks.
- Employed in port and dock maintenance tasks, such as:
- Securing temporary barriers (e.g., to block off construction zones
on docks);
- Tying down maintenance equipment (e.g., hoses, tools) to prevent
loss overboard;
- Assisting in lifting light components (e.g., small metal parts,
cleaning supplies) using pulleys.
Its resistance to saltwater and UV radiation ensures longevity,
even with constant exposure to marine environments.
2. Main performance
Material | Polyamide Multifilament | Polyamide Yarn | Polypropylene Multifilament | Polypropylene | Polyester | Polypropylene and Polyester Mixed |
Spec.Density | 1.14 no floating | 1.14 not floating | 0.91 no floating | 0.91 Floating | 1.27 no floating | 0.95 Floating |
Melting Point | 215℃ | 215℃ | 165℃ | 165℃ | 260℃ | 165℃/260℃ |
Abrasion Resistance | Very Good | Very Good | Medium | Medium | Good | Good |
U.V.Resistance | Very Good | Very Good | Medium | Medium | Good | Good |
Temperature resistance | 120℃max | 120℃max | 70℃max | 70℃max | 120℃max | 80℃max |
Chemical resistance | Very Good | Very Good | Good | Good | Good | Good |
3.Technology Comparison
Coil length: 220m
Spliced strength:± 10% lower
Weight and length tolerance:± 5%
MBL=Minimum Breaking Load conform ISO 2307
Other sizes available upon request

4.Parameter Table
Specification 规格 | PA Multifilament 锦纶复丝 | PAYarn 锦纶 | PP Multifilament 丙纶长丝 | Polypropylene 丙纶 | Polyester 涤纶 | PET/PP Mixed 丙纶/涤纶混合绳 |
Dia. | Cir | Ktex | KN | Ktex | KN | Ktex | KN | Ktex | KN | Ktex | KN | Ktex | KN |
直径 | 圆 周 | 线密度 | 破断强力 | 线密度 | 破断强力 | 线密度 | 破断强力 | 线密度 | 破断强力 | 线密度 | 破断强力 | 线密度 | 破断强力 |
4 | 1/2 | 10 | 3.7 | 10 | 2.6 | 6.3 | 2.3 | 6 | 2.1 | 12 | 2.9 | 7.0 | 2.8 |
6 | 3/4 | 22 | 7.9 | 22 | 6 | 18 | 6.5 | 17 | 5.9 | 27 | 5.6 | 17.5 | 6.8 |
8 | 1 | 40 | 13.8 | 40 | 10.9 | 32 | 11.4 | 30 | 10.4 | 48 | 10.0 | 31 | 11.9 |
10 | 1-1/4 | 62 | 21.2 | 62 | 15.7 | 47 | 16.8 | 45 | 15.3 | 76 | 15.6 | 48.5 | 18.2 |
12 | 1-1/2 | 89 | 30.1 | 89 | 24.1 | 68 | 23.9 | 65 | 21.7 | 110 | 22.3 | 69.9 | 25.7 |
14 | 1-3/4 | 121 | 40.0 | 121 | 33.0 | 95 | 32.9 | 90 | 29.9 | 148 | 31.2 | 95.1 | 34.7 |
16 | 2 | 158 | 51.9 | 158 | 42.5 | 121 | 40.7 | 115 | 37.0 | 195 | 39.8 | 124 | 44.8 |
18 | 2-1/4 | 200 | 64.3 | 200 | 53.9 | 155 | 51.9 | 148 | 47.2 | 245 | 49.8 | 157 | 56.1 |
20 | 2-1/2 | 247 | 79.2 | 247 | 66.7 | 189 | 62.6 | 180 | 56.9 | 303 | 62.3 | 194 | 68.7 |
22 | 2-3/4 | 299 | 94.0 | 299 | 80.4 | 231 | 75.0 | 220 | 68.2 | 367 | 74.7 | 235 | 82.1 |
24 | 3 | 355 | 112 | 355 | 93.6 | 273 | 87.7 | 260 | 79.7 | 437 | 89.6 | 279 | 96.3 |
26 | 3-1/4 | 417 | 129 | 417 | 111.5 | 320 | 101 | 305 | 92.2 | 512 | 105 | 328 | 113 |
28 | 3-1/2 | 484 | 149 | 484 | 127 | 373 | 115 | 355 | 105 | 594 | 120 | 380 | 130 |
30 | 3-3/4 | 555 | 169 | 555 | 143 | 425 | 132 | 405 | 120 | 682 | 134 | 437 | 148 |
32 | 4 | 632 | 192 | 632 | 161 | 483 | 146 | 460 | 132 | 778 | 154 | 497 | 167 |
36 | 4 - 1/ 2 | 800 | 240 | 800 | 200 | 614 | 182 | 585 | 166 | 982 | 190 | 629 | 210 |
40 | 5 | 987 | 294 | 987 | 241 | 756 | 221 | 720 | 201 | 1215 | 235 | 776 | 257 |
44 | 5-1/2 | 1190 | 351 | 1190 | 289 | 924 | 266 | 880 | 242 | 1468 | 275 | 939 | 308 |
48 | 6 | 1420 | 412 | 1420 | 338 | 1092 | 308 | 1040 | 280 | 1750 | 329 | 1110 | 364 |
52 | 6-1/2 | 1670 | 479 | 1670 | 393 | 1281 | 357 | 1220 | 325 | 2050 | 384 | 1320 | 424 |
56 | 7 | 1930 | 550 | 1930 | 450 | 1491 | 408 | 1420 | 371 | 2380 | 439 | 1520 | 489 |