3-Strands Plastic PP (Polypropylene) Rope Twisted Fishing Net Rope

1. Production Process of 3-Strands Plastic PP Rope (Twisted Type for Fishing Net & Packaging)

Step 1: Raw Material Preparation (PP Resin Processing)

• Raw Material Selection: Use high-quality polypropylene (PP) resin pellets as the core raw material. Add functional additives (e.g., UV stabilizers for outdoor resistance, anti-aging agents, or color masterbatches for specific hues) based on application needs (e.g., UV stabilizers are mandatory for fishing nets exposed to sunlight).
• Drying Treatment: Pre-dry PP pellets in a hopper dryer (at 80–100°C for 2–4 hours) to remove moisture. This prevents bubble formation in the extruded filaments, which could weaken the rope’s structure.

Step 2: Extrusion & Filament Formation (Monofilament/Polyfilament Production)

• Melting & Extrusion: Feed dried PP pellets into a single-screw extruder. The extruder heats the pellets to 220–260°C (the melting point of PP) to form a molten PP fluid.
• Filament Extrusion: The molten PP is pushed through a spinneret (a metal plate with hundreds of tiny holes) to form continuous, thin filaments (monofilaments). For ropes requiring higher flexibility (e.g., packaging ropes), multiple monofilaments are lightly twisted together to form polyfilaments.
• Cooling & Solidification: The extruded filaments are immediately cooled in a water bath (20–30°C) to solidify their shape, ensuring uniform thickness and structural stability.

Step 3: Drawing (Strengthening Filaments)

• The cooled filaments are pulled through a series of heated rollers (drawing machine) at a controlled speed. This “drawing” process stretches the filaments, aligns the PP molecular chains, and increases their tensile strength and wear resistance—critical properties for fishing nets (to withstand water pressure and fish pulling) and packaging (to bear load weight).

Step 4: Stranding (Forming Single Strands)

• Gather a fixed number of drawn filaments (the quantity depends on the desired rope thickness) and twist them together using a stranding machine. This forms single PP strands with consistent twist density (measured by twists per meter, TPM). The twist direction (S-twist or Z-twist) is standardized to ensure uniformity for subsequent twisting.

Step 5: 3-Strand Twisting (Core Rope Formation)

• Feed three identical single strands into a 3-strand twisting machine. The machine twists the three strands together in the opposite direction of the single-strand twist (e.g., if single strands are S-twisted, the 3-strand rope is Z-twisted). This “counter-twisting” balances tension, prevents the rope from unraveling, and enhances its overall stability.
• Adjust the twisting speed and tension to control the rope’s diameter (e.g., 4mm–20mm for fishing nets, 8mm–30mm for packaging) and tensile strength.

Step 6: Post-Processing & Quality Inspection

• Heat Setting: Pass the twisted rope through a heat-setting oven (100–120°C) to stabilize its twist structure, reducing shrinkage during use (especially important for fishing nets in water or packaging exposed to temperature changes).
• Cutting & Winding: Cut the rope into fixed lengths (e.g., 50m, 100m, or custom lengths) and wind it onto spools, reels, or coils for easy storage and transportation.
• Quality Testing: Conduct tests to verify key performance indicators:
  • Tensile strength (to ensure it can bear required loads).
  • Abrasion resistance (for fishing nets’ long-term use in water or packaging’s contact with goods).
  • UV resistance (for outdoor fishing or open-air storage of packaged goods).
  • Thickness uniformity (to avoid weak points in the rope).

Step 7: Packaging of the Rope

• Package the finished 3-strands PP rope (on spools/reels) with waterproof plastic film or cardboard boxes. Label each package with specifications (diameter, length, tensile strength, application) for customer identification.

2. Application Scope of 3-Strands Plastic PP Rope (Twisted Fishing Net Rope & Packaging Rope)

2.1 Fishing Industry (As Twisted Fishing Net Rope)

• Fishing Net Weaving: The primary application—used as the core material to weave various fishing nets (e.g., gill nets, trawl nets, seine nets). Its water resistance prevents rot (unlike natural fibers), and UV resistance ensures long service life under sunlight. The 3-strand twist provides enough flexibility to adapt to water flow while maintaining the net’s shape.
• Fishing Vessel Mooring: Used as mooring ropes for small-to-medium fishing boats. Its lightweight nature makes it easy to handle, and its high tensile strength can withstand wave impacts and vessel weight.
• Catch Handling: Used to tie and haul fish catches (e.g., securing fish crates or bundles). It is non-toxic (safe for food contact) and easy to clean, avoiding contamination of catches.

2.2 Packaging Industry

• Heavy-Duty Goods Packaging: Ideal for securing heavy items during transportation (e.g., wooden pallets, machinery parts, construction materials). The 3-strand twist’s high tensile strength prevents the rope from snapping under load, ensuring goods stay stable.
• Carton Sealing & Bundling: Used to bundle multiple cartons, bags, or packages (e.g., agricultural products like rice bags, industrial components). It is flexible enough to wrap around irregular shapes and does not damage packaging surfaces.
• Warehouse Storage: Used to secure stacked goods (e.g., stacked cartons or barrels) in warehouses, preventing collapse due to shifting. Its corrosion resistance means it can be used in humid warehouse environments without rusting (unlike metal wires).

2.3 Agriculture & Aquaculture

• Crop Support: Used to support climbing crops (e.g., tomatoes, beans, grapes). It is durable enough to bear the weight of mature crops and resistant to rain and sunlight, avoiding degradation over the growing season.
• Aquaculture Cages: Used to build and secure aquaculture cages (for fish, shrimp, or shellfish). Its water resistance and anti-aging properties ensure long-term use in marine or freshwater environments, and it does not leach harmful substances into the water.

2.4 Construction & Outdoor Activities

• Temporary Securement: Used in construction sites to secure temporary structures (e.g., scaffolding netting, construction materials like pipes or lumber). It is easy to install and remove, and its strength meets short-term load requirements.
• Outdoor & Recreational Use: Used for camping (e.g., securing tents, hanging gear), hiking (e.g., emergency ropes), or backyard activities (e.g., building bird feeders, supporting garden trellises). Its lightweight and portable nature makes it a practical choice for outdoor enthusiasts.

2.5 Shipping & Logistics

• Container & Cargo Securement: Used to secure cargo on trucks, ships, or trains (e.g., securing furniture, appliances, or bulk goods). It resists saltwater corrosion (critical for maritime shipping) and maintains tension even during long journeys, preventing cargo shifting.