Product Specification

Fishing marine Polypropylene PP danline 3 /4 strands twisted PP floating polysteel rope

1.PHOTOS

2. Main performance

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

1. Production Process

Step 1: Raw Material Preparation & Fiber Extrusion

• Polypropylene (PP) Pellet Selection: High-quality, marine-grade PP pellets are chosen for their low density (enabling floating), resistance to saltwater, and UV stability. Additives (e.g., UV inhibitors, anti-aging agents) are mixed into the pellets to enhance durability against harsh marine conditions.
• Fiber Spinning: The blended PP pellets are melted in an extruder and forced through spinnerets (fine holes) to form continuous PP filaments. These filaments are cooled rapidly to solidify, then stretched to align the molecular structure—boosting tensile strength and reducing elongation.
• Polysteel Component Integration: For the "polysteel" property, high-strength synthetic fibers (e.g., high-tenacity PP or polyester) are extruded alongside the base PP filaments. These reinforcing fibers are designed to enhance the rope’s load-bearing capacity without increasing density (critical for maintaining floatability).

Step 2: Filament Twisting (Yarn Formation)

• The extruded PP filaments (and reinforcing polysteel fibers) are grouped into bundles, then twisted into individual yarns. This twisting process tightens the fibers, improving cohesion and preventing fraying. The yarn count and twist rate are calibrated to balance flexibility and strength—key for fishing operations that require easy handling.

Step 3: Strand Formation

• For 3-strand or 4-strand designs:
  • 3-strand rope: Three equal lengths of twisted PP-polysteel yarn are prepared.
  • 4-strand rope: Four equal lengths of twisted PP-polysteel yarn are prepared.
• Each group of yarns is twisted again to form solid, uniform strands. The twist direction (e.g., "S-twist" or "Z-twist") is controlled to ensure consistency across all strands, which is vital for structural stability in the final rope.

Step 4: Final Rope Twisting (Strand Assembly)

• The 3 or 4 prepared strands are fed into a twisting machine, where they are twisted together in the opposite direction of their individual strand twist (e.g., Z-twist for strands if the final rope uses S-twist). This "counter-twisting" creates a balanced, non-rotational rope that resists unraveling and maintains shape under tension—critical for fishing tasks like casting or hauling.
• The twist tightness is adjusted to meet floating requirements: a moderate twist ensures the rope retains enough air pockets (from PP’s low density) to stay buoyant, while avoiding over-tightening that could compress fibers and reduce floatability.

Step 5: Post-Processing & Quality Inspection

• Trimming & Cutting: The finished rope is trimmed to standard lengths (e.g., 50m, 100m) and cut with heat-sealed ends to prevent fraying.
• Surface Treatment (Optional): A clear, water-based coating may be applied to enhance abrasion resistance and reduce friction—useful for contact with fishing reels or boat hardware.
• Quality Checks: Each batch is tested for:
  • Floatability (ensuring it stays on water surface for at least 24 hours).
  • Tensile strength (meeting marine fishing load requirements).
  • Saltwater resistance (immersion in saltwater for 72 hours to check for fiber degradation).
  • Twist consistency (no strand slippage under load).

2. Application Scope

1. Recreational & Small-Scale Fishing

• Casting Lines for Inshore Fishing: Ideal for fishing in shallow to mid-depth coastal waters (e.g., estuaries, bays) where floatability helps track bait or lures. Its light weight and flexibility make it easy to cast with hand-held rods or small reels, while the polysteel reinforcement handles the weight of medium-sized fish (e.g., bass, snapper).
• Trawl Lines for Small Fishing Boats: Used as secondary trawl lines for small-scale commercial or recreational trawling. The floating design keeps the line near the water surface, preventing it from tangling with seabed debris, and the PP material resists saltwater corrosion from daily use.

2. Commercial Fishing Support

• Net Tying & Securing: Used to assemble, repair, or secure fishing nets (e.g., gill nets, seine nets). Its twist structure ensures tight, secure knots that hold under the tension of netting filled with fish, and its floatability helps keep surface nets (e.g., purse seines) aligned correctly.
• Buoy Lines: Attached to fishing buoys to mark net positions, trap locations, or safe navigation paths. The rope’s floatability keeps the buoy visible above water, even in rough seas, and its UV resistance prevents degradation from prolonged sun exposure.

3. Boat & Vessel Safety

• Emergency Line for Small Vessels: Serves as a lightweight emergency line (e.g., throw lines) for small fishing boats or dinghies. Its floatability ensures it stays on water if deployed to rescue crew or retrieve overboard gear, and the polysteel reinforcement provides enough strength to pull objects or people to safety.
• Mooring Lines for Small Craft: Used as temporary mooring lines for small fishing boats when docking at coastal ports or temporary anchor points. Its floatability reduces water absorption (avoiding weight gain) and its PP material resists rot from constant saltwater contact.

4. Aquaculture Operations

• Cage Securement for Fish Farms: Used to secure floating fish cages (e.g., for salmon, tilapia) in coastal or offshore aquaculture. The rope’s floatability helps maintain cage position near the water surface, and its durability withstands constant exposure to saltwater, waves, and aquatic life (e.g., barnacles).
• Feeder Line Guides: Guides automated feeder systems in aquaculture farms, ensuring feed is distributed evenly to fish. Its smooth surface prevents feed from sticking, and its flexibility allows it to adapt to the movement of floating feeders.

5. Recreational Water Activities

• Water Sports Safety Lines: Used in non-fishing marine activities like kayaking, paddleboarding, or water skiing as a safety or tow line. Its floatability makes it easy to retrieve if dropped, and its light weight avoids dragging down users.
• Swim Area Markers: Defines temporary swim zones in coastal campsites or marinas. The floating rope is visible above water, and its saltwater resistance ensures it lasts through seasonal use.